CHP: Review Of NDM-1 In Hong Kong

Inoculated MacConkey agar culture plate cultivated colonial growth of Gram-negative, small rod-shaped and facultatively anaerobic Klebsiella pneumoniae bacteria. – CDC PHIL.

 

# 6719

 

The Centre for Health Protection publishes a weekly Communicable Disease Watch, where they highlight recent infectious disease events in and around Hong Kong.

 

Today, they include a review of the resistance enzyme NDM-1 (New Delhi metallo-ß-lactamase-1) which was first detected in a patient in Sweden (albeit with Indian origins) four years ago, but has subsequently spread to many countries around the world.

 

This enzyme confers resistance to certain gram negative bacteria like E.coli and Klebsiella against a class of antibiotics called carbapenems. Carbapenems are often our drug of last resort against a variety of bacterial infections.

 

Of particular concern, this enzyme is carried by a plasmid – a snippet of portable DNA  - that can be transferred to other types of bacteria (see Study: Adaptation Of Plasmids To New Bacterial Species).

 

The rise of antibiotic resistance - including this emerging NDM-1 enzyme - has long been linked to the overuse and misuse of antibiotics. A practice that is still widespread in many parts of the world, but is particularly rampant on the Indian sub-continent.

 

Citing a lack of doctors and low family incomes, the Indian government (see India: Still Looking For A Policy On Antibiotics) has been slow to stop the sale of antibiotics to the public without a doctor’s prescription.

 

It’s been more than 2 years since The Lancet published a study (see NDM-1: A New Acronym To Memorize)  by Walsh, Toleman, Livermore, et al. that sounded the alarm on the emergence and growing prevalence of the NDM-1 enzyme on the Indian sub-continent.

 

Since that time, we’ve seen a slow, but inexorable spread of NDM-1 carrying bacteria around the globe. A few of my past blogs on the subject include:

 

Carbapenemases Rising

NDM-1: One Year Later

WHO Unveils 6-Point Plan To Preserve Antibiotic Effectiveness

Eurosurveillance On Antimicrobial Resistance

 

 

Today’s report from the HPC indicates that they have identified 17 patients carrying the NDM-1 enzyme over the past four years, with one case each in 2009 and 2010, three cases in 2011, and 12 cases so far in 2012.

 

Many of these cases were colonized and detected through routine screening, but were asymptomatic. As this report indicates:

 

Infections varied from colonisation or mild to potentially life threatening or fatal. The level of risk depends upon which body part is infected and general health of the patient.

 

I’ve included some excerpts, but follow the link to read:

 

 

Source CHP Communicable Disease Watch

Among the 17 cases, 13 (76%) were male, and the median age was 64 years (ranged from 11 months to 94 years). Fourteen (82%) were Chinese, 2 Indian and 1 Burmese.

 

Among 16 imported cases, all except one had history of admission to hospitals while staying abroad. Twelve were hospitalised in Mainland China (8 in Guangdong province, 2 in Hunan province, 1 in Fujian province and 1 in Henan province), one in India, one in Myanmar and one in Thailand. Six (40%) of them had operations done during their hospitalisation.

 

The one without history of admission to hospital was a 66-year-old male patient of Indian ethnicity and he had travelled to India before onset of symptoms. Four cases had signs of infection (2 had chest infection, 1 urinary tract infection and 1 leg infection). 

 

Thirteen were asymptomatic colonisation detected by screening or contact tracing. One had the bacteria yielded from both sputum and rectal swab specimens. Two cases passed away due to underlying illness and aspiration pneumonia respectively.

 

In September 2012, CHP identified an import-related NDM-1 case affecting a 64-year-old man. A rectal swab was taken for this patient as part of the contact tracing exercise for another imported NDM-1 patient (78-year-old man) from Myanmar. They had stayed in the same cubicle of a hospital ward in Hong Kong.

 

The rectal swab was tested positive for NDM-1. Pulsed-field gel electrophoresis patterns of the two NDM-1 strains were subsequently found to be identical by the Public Health Laboratory Services Branch (PHLSB) of CHP.

This suggests that the 64-year-old case was epidemiologically linked to the 78-year-old imported case. Thirteen other patients stayed in the same cubicles as the case patients for more than 48 hours were screened by rectal swabs and all were tested negative.

 

 

This week is antibiotic awareness week (see A Health Crisis In Slow Motion) here in the United States, as it is in many places around the world. The erosion of the effectiveness of our antimicrobial arsenal increases with each year, and leads many doctors and scientists to worry that we’ll eventually lose the ability to treat even common infections.

 

For a far more complete discussion of antimicrobial resistance issues, I can think of no better primer than Maryn McKenna’s book SUPERBUG: The Fatal Menace of MRSA. And Maryn’s SUPERBUG Blog, part of Wired Science Blogs, continues to provide the best day-to-day coverage of these issues.

»» Read More

A Health Crisis In Slow Motion

 

 

# 6715

 

Although truly the miracle drugs of the 20th century, antibiotics are a fragile armamentarium, and over the past 70 years we’ve learned just how quickly bacteria can evolve to evade their antimicrobial effects.

 

Antimicrobial resistance is a huge and growing threat to public health – perhaps the greatest threat of all. 

 

Yet it is largely unappreciated by the public because its progression has been gradual, the loss of antibiotics incremental, and so far at least . . . there have always been replacement drugs available when an antibiotic has failed.

 

But the number of new antibiotics in the pipeline are desperately few, and the frequency of newly emerging resistant bugs has increased in recent years. 

 

Last March, the Director General of the World Health Organization, Margaret Chan - in a keynote address to the Conference on Combating Antimicrobial Resistance in Copenhagen - painted a bleak picture of the future of antibiotic availability if action is not taken.

 

The D-G’s entire remarks may be viewed on the WHO’s website at Antimicrobial resistance in the European Union and the world, but I’ve excerpted a few choice statements below.

 

If current trends continue unabated, the future is easy to predict. Some experts say we are moving back to the pre-antibiotic era. No. This will be a post-antibiotic era. In terms of new replacement antibiotics, the pipeline is virtually dry, especially for gram-negative bacteria. The cupboard is nearly bare.

 

<SNIP>

 

A post-antibiotic era means, in effect, an end to modern medicine as we know it. Things as common as strep throat or a child’s scratched knee could once again kill.

 

Some sophisticated interventions, like hip replacements, organ transplants, cancer chemotherapy, and care of preterm infants, would become far more difficult or even too dangerous to undertake.

 

This week (Nov. 12th-18th) marks the CDC’s fifth annual Get Smart About Antibiotics Week, which coincides with observances in many regions around the world, including  European Antibiotic Awareness Day, Australia's Antibiotic Awareness Week and Canada's Antibiotic Awareness Week.

 

The theme of this campaign is the smart usage of antibiotics, and educating the public on the fact that these drugs won’t cure a viral infection, and their overuse leads to resistance.  

 

Get Smart. Take a look at this chart to find out which upper respiratory infections are usually caused by viruses — germs that are not killed by antibiotics. Talk with your doctor about ways to feel better when you are sick. Ask what you should look for at home that might mean you are developing another infection for which antibiotics might be appropriate.

 

For some ideas about what to do for these types of illnesses without taking antibiotics, the CDC has a Symptom Relief webpage.

 

Still, many people expect an antibiotic when they go to their doctor with a respiratory infection (and many doctors continue to prescribe them).

 

 

Maryn McKenna has more on the public’s often errant perception of proper antibiotic use, and on highly divergent physician prescribing habits across the country. Follow the link to read:

 

The Persistence of Resistance And Some Reasons Why

• By Maryn McKenna
• November 13, 2012 |  

 

 

The `go to’ person on all things antibiotic resistant in the blogosphere is undoubtedly Maryn McKenna, author of Superbug: The Fatal Menace of MRSA and editor of the Superbug Blog. Both of which I highly recommend.

 

I, on occasion, do wade into the shallower depths of the antimicrobial pool in this blog. A few recent examples include:

 

EID Journal: Challenges To Defining TDR-TB

India: Still Looking For A Policy On Antibiotics

MMWR: NDM-1 Transmission In Rhode Island

ECDC Response Plan To Multi-Drug Resistant Gonorrhea

CDC Grand Rounds: Multidrug-Resistant Gonorrhea

 

 

The problems of antimicrobial resistance go far beyond the overuse, or misuse of antibiotics by the American public. Other threats include:

 

• The FDA estimates US livestock get 29 million pounds of antibiotics per year, or roughly 80% of all antibiotics used in this country. 
• The indiscriminate sale and use of antibiotics in places like India, Latin America, and parts of Eastern Europe (see India: Still Looking For A Policy On Antibiotics).
• The (illegal) trade in fake, out-of-date, or otherwise compromised antibiotics from online pharmacies (see Interpol & FDA: Operation Pangea V)
• And the excretion into the environment of bioactive antibiotic metabolites (see Pandemics & The Law Of Unintended Consequences).

 

 

It will take a multi-pronged, international effort to slow the growth of antibiotic resistance. Agencies like the FDA, CDC, WHO, and ECDC are working towards finding solutions, but there are many competing interests and much bureaucratic red tape.

 

Progress is often slow. 

 

Other than supporting the wise use of antibiotics internationally, admittedly as individuals we can’t do much about the use of antibiotics in India, or on the farm, or sold over the internet.

 

But we can be smart about how we use these drugs. Part of the solution is not being part of the problem.

 

We either exercise proper stewardship over the remaining drugs we have (and hope that new ones can be developed) or we face a very grim future where minor infections - once easily defeated -  will once again claim millions of lives.

»» Read More

India: Still Looking For A Policy On Antibiotics

 

Inoculated MacConkey agar culture plate cultivated colonial growth of Gram-negative, small rod-shaped and facultatively anaerobic Klebsiella pneumoniae bacteria. – CDC PHIL.

# 6502

 

Although the antibiotic resistance enzyme now known as NDM-1 (New Delhi metallo-ß-lactamase-1) was first detected in a patient in Sweden (albeit with Indian origins) four years ago, it didn’t capture much attention until the publication of an eye-opening research paper in The Lancet in August of 2010.

 

Emergence of a new antibiotic resistance mechanism in India, Pakistan, and the UK: a molecular, biological, and epidemiological study

Dr David Livermore, Prof Timothy Walsh, et al.

doi:10.1016/S1473-3099(10)70143-2

Published Online: 11 August 2010

 

This study linked the recent importation of a handful of NDM-1 infections into the UK, US, and other countries  to `medical tourism’ on the Indian Sub-continent (see NDM-1: A New Acronym To Memorize).

 

NDM-1 is an enzyme confers resistance to certain gram negative bacteria like E.coli and Klebsiella against a class of antibiotics called carbapenems. Carbapenems are often our drug of last resort against a variety of bacterial infections.

 

Of particular concern, this enzyme is carried by a plasmid – a snippet of portable DNA  - that can be transferred to other types of bacteria (see Study: Adaptation Of Plasmids To New Bacterial Species).

 

 

The rise of antibiotic resistance has long been linked to the overuse and misuse of antibiotics.

 

Citing a lack of doctors and low family incomes, the Indian government allows the unfettered sale of antibiotics to the public without a doctor’s prescription.

 

Indian officials swiftly reacted to the Lancet paper, but rather than taking immediate action against a growing public health menace, they took umbrage instead.

 

They condemned of the use of `New Delhi’ in the naming of this resistance gene and called the paper a `conspiracy theory’.  They issued broad denials of its prevalence in India or that medical tourism to their nation was responsible for its spread.

 

It is worth noting that the naming convention for pathogens that invoked India’s ire has long used the pathogen’s place of discovery or emergence. India was certainly not singled out.

 

After intense pressure from the International community and scathing editorializing in Indian newspapers, the Indian Health Ministry announced in October 2010 that they would impose new restrictions on the sale of 90 antibiotics that were currently sold over-the-counter.

 

But that plan was eventually abandoned. Two years later, the sale of antibiotics remains rampant and unregulated in India.

 

This article appeared last week in The Hindu.

 

 

Wanted: a policy on antibiotics

R. Sujatha

It needed a scare like NDM-1 for the country to wake up to a policy to regulate antibiotics. But after announcing with much fanfare that a policy would be in place, the government withdrew the decision. We have arrived at a crossroads and there is no solution to the crisis yet.

(Continue . . .)

 

 

The story goes on to say that next week doctors from around the country will meet in Chennai to try to come up some kind of  `road map’ for the government to use to implement an antibiotic policy. 

 

Whether they will succeed, and whether the government will follow through, remains to be seen.

 

Meanwhile, as policy makers dither, the NDM-1 enzyme continues its evolution and spread.

 

Six months after the first Lancet article in April, 2011, the same researchers published a another study that found the NDM-1 enzyme in 4% of New Delhi’s sampled drinking water sources, and 30 per cent of the sewage tested.

 

The Lancet Infectious Diseases, Early Online Publication, 7 April 2011

doi:10.1016/S1473-3099(11)70059-7

Dissemination of NDM-1 positive bacteria in the New Delhi environment and its implications for human health: an environmental point prevalence study

Prof Timothy R Walsh PhD , Janis Weeks BS, David M Livermore PhD , Mark A Toleman PhD

 

And most alarmingly, the researchers also identified 11 new species of bacteria carrying the NDM-1 gene, including strains which cause cholera and dysentery.

 

Once again the reaction out of India was one of denial (see Hopefully, It’s Just A Stage They Are Going Through). 

 

Last fall, despite ongoing denials from the Indian government, we saw a number of stories that helped to corroborate the findings of these two much-maligned-in-India Lancet studies.

 

First stop, the The Economic Times.

Ganga Ram study finds high levels of superbug NDM1

5 Oct, 2011, 1114 hrs IST, Durgesh Nandan Jha, TNN

NEW DELHI: India might have vehemently opposed an antibiotic-resistant superbug being named New Delhi Metallo-beta-lactamase 1 (NDM1), but a study in a leading city hospital has found a worryingly high prevalence of the deadly gene.

(Continue . . . )

 

 

The study, conducted over a 5-month period, examined 10,889 samples from patients. The NDM1 resistance gene was found in 8.1% of E. coli samples and 38.02% of samples of K. pneumoniae.

 

In the article, Dr S P Byotra, chairperson of medicine at the Ganga Ram Hospital, is quoted as saying:

 

"The idea behind this study is to stop denying the crisis NDM1 poses and work out strategies to check its spread. Antibiotic usage needs to be monitored strictly and good infection-control methods should be put in place at hospitals."

 

Another related article, that appeared in the International Business Times, quotes Former Indian Council of Medical Research chief and chairman N.K. Ganguly as saying that the multi-drug resistant New Delhi metallo-beta-lactamase-1 or NDM-1 comes from hospital waste that goes into Delhi's sewage water.

 

Presence of Antibiotic-Resistant Bacteria in Delhi Confirmed

October 5, 2011 1:26 PM EST

 

 

Last March (see Chan: World Faces A `Post-Antibiotic Era’), World Health Organization Director-General Margaret Chan – delivering the  keynote address to the Conference on Combating Antimicrobial Resistance in Copenhagen, Denmark - painted a bleak picture of the future of antibiotic availability if action is not taken.

 

The D-G’s entire remarks may be viewed on the WHO’s website at Antimicrobial resistance in the European Union and the world, but I’ve excerpted a few choice statements below, after which you’ll find a link to the World Health Organization’s latest publication on antibiotic resistance.

 

Excerpts from D-G Chan’s March 14th, 2012 speech.

 

Antimicrobial resistance is on the rise in Europe, and elsewhere in the world. We are losing our first-line antimicrobials. Replacement treatments are more costly, more toxic, need much longer durations of treatment, and may require treatment in intensive care units.

 

<SNIP>

 

If current trends continue unabated, the future is easy to predict. Some experts say we are moving back to the pre-antibiotic era. No. This will be a post-antibiotic era. In terms of new replacement antibiotics, the pipeline is virtually dry, especially for gram-negative bacteria. The cupboard is nearly bare.

 

<SNIP>

 

A post-antibiotic era means, in effect, an end to modern medicine as we know it. Things as common as strep throat or a child’s scratched knee could once again kill.

The evolving threat of antimicrobial resistance - Options for action

Authors:
World Health Organization

 

 

To be fair, India isn’t the only country with NDM-1 cases or growing carbapenem resistance. But the Indian sub-continent does appear to be a focal point – a situation often linked to their lax controls on the sale and use of antibiotics.

 

Short of seeing a hyper-virulent pandemic someday, I can think of no public health crisis with a bigger potential impact than the growth of antibiotic resistant pathogens.

 

While I dabble in the subject from time to time, without a doubt  the `go to’ blogger on all things antibiotic resistant is Maryn McKenna, author of Superbug: The Fatal Menace of MRSA. 

 

 

If you aren’t a regular visitor to her Superbug Blog, you should be.

 

If and when the Indian government imposes meaningful restrictions on the sale of antibiotics, I’ll report it. 

 

One just hopes that happens before the point becomes moot.

»» Read More

EID: Environmental NDM-1 Detected In Vietnam

Inoculated MacConkey agar culture plate cultivated colonial growth of Gram-negative, small rod-shaped and facultatively anaerobic Klebsiella pneumoniae bacteria. – CDC PHIL.

 

# 6440

 

In a study reminiscent of one we saw published in April of last year (see Lancet Study: NDM-1 In New Delhi Water Supply), the CDC’s EID Journal has a letter by R. Isozumi et al. that appears (ahead of print) in their August issue, that reveals the detection of the NDM-1 gene in a river in Hanoi.

 

bla_NDM-1–positive Klebsiella pneumoniae from Environment, Vietnam

Rie Isozumi , Kumiko Yoshimatsu, Tetsu Yamashiro, Futoshi Hasebe, Binh Minh Nguyen, Tuan Cuong Ngo, Shumpei P. Yasuda, Takaaki Koma, Kenta Shimizu, and Jiro Arikawa

 

By way of explanation, bla_NDM-1 is the gene responsible for creating the NDM-1 (New Delhi metallo-β-lactamase) enzyme that can make many types of bacteria resistant to a wide spectrum of antibiotics.

 

Of particular concern, this enzyme is carried by a plasmid – a snippet of portable DNA  - that can be transferred to other types of bacteria (see Study: Adaptation Of Plasmids To New Bacterial Species).

 

Over the past few years we have seen a worrisome expansion of β-lactamase enzymes in bacteria, and they are slowly eroding the value of much of our antibiotic arsenal.

 

Those that inhibit the antimicrobial actions of the (formerly resistant) Carbapenem class of antibiotics – called carbapenemases – are of particular concern. Carbapenems are often used as the drug of last resort for treating difficult bacterial infections, including Escherichia coli (E. coli) and Klebsiella pneumoniae.

 

So when the gene responsible for the NDM-1 enzyme begins to show up in the environment, doctors and researchers take notice.

 

The author’s of today’s EID Journal report state their reasons for concern:

 

The possible appearance of bacteria harboring bla_NDM-1 in Vietnam is of concern because cultural and economic links between Vietnam and India are strongly established, including extensive person-to-person exchanges that could enable easy exchange of pathogens. In addition, Vietnam faces a serious problem of antimicrobial drug resistance because drugs are freely available and used in an indiscriminate fashion. Thus, once bla_NDM-1–positive bacteria colonize persons in Vietnam, they would be able to spread easily and pose a serious public health threat.

 

To look for environmental bla_NDM-1, researchers examined water samples taken from 20 locations within 10 km of Hanoi, Vietnam. Samples were collected from rivers, lakes, and standing water in the streets.

The authors report finding the NDM-1 enzyme producing gene in two locations – 3km apart – in the Kim Nguu River, which flows through the city.  They write:

 

We harvested several species of bacteria from the 2 seepage samples positive for bla_NDM-1: Acinetobacter baumannii, Klebsiella pneumoniae, Pseudomonas aeruginosa, P. fluorescens/putida, and P. luteola. 

 

They also report finding 2 other βeta-lactamases (bla_TEM-1 and bla_CTX-M-3) that were highly resistant to another class of antibiotics called aminoglycosides (which include neomycin, streptomycin & tobramycin)

The authors conclude by saying:

Wide-scale surveillance of environmental and clinical samples in Vietnam and establishment of a strategy to prevent further spread of bla_NDM-1 are urgently needed.

It’s been nearly 2 years since The Lancet published a study (see NDM-1: A New Acronym To Memorize)  by Walsh, Toleman, Livermore, et al. that awakened the world to the  emergence and growing prevalence of the NDM-1 enzyme.

 

Since that time, we’ve seen a slow, but inexorable spread of NDM-1 carrying bacteria around the globe. A few of my past blogs on the subject include:

 

Carbapenemases Rising

NDM-1: One Year Later

WHO Unveils 6-Point Plan To Preserve Antibiotic Effectiveness

Eurosurveillance On Antimicrobial Resistance

 

For a far more complete discussion of antimicrobial resistance issues, I can think of no better primer than Maryn McKenna’s book SUPERBUG: The Fatal Menace of MRSA. And Maryn’s SUPERBUG Blog, part of Wired Science Blogs, continues to provide the best day-to-day coverage of these issues.

 

Last March, Director-General of the World Health Organization Margaret Chan warned that the World Faces A `Post-Antibiotic Era’. One where even common infections may become untreatable.

 

While we aren’t there yet, reports such as the one today in the EID Journal add to the growing concern that someday, that fear may become a reality.

»» Read More

MMWR: NDM-1 Transmission In Rhode Island

 

Inoculated MacConkey agar culture plate cultivated colonial growth of Gram-negative, small rod-shaped and facultatively anaerobic Klebsiella pneumoniae bacteria. – CDC PHIL.

 

 

# 6397

 

From the today’s MMWR , we’ve a report on the importation and likely nosocomial transmission of a CRE (carabapenem-resistant Enterobacteriaceae) infection containing NDM-1.

 

NMD-1, or New Delhi metallo-ß-lactamase-1 – is an enzyme which confers broad antibiotic resistance to various types of bacteria. Even more troubling, it rides on a plasmid (a snippet of portable DNA) that can be shared by different types of bacteria.

 

The good news is that NDM-1 cases in the United States are still rare enough that they merit extensive reportage in the CDC’s MMWR. The bad news is, they continue to spread around the globe and our treatment options against them are extremely limited.

 

A few excerpts from today’s MMWR report follow (slightly reparagraphed for readability). 

 

 

Carbapenem-Resistant Enterobacteriaceae Containing New Delhi Metallo-Beta-Lactamase in Two Patients — Rhode Island, March 2012

 

June 22, 2012 / 61(24);446-448

U.S. and international efforts to control carabapenem-resistant Enterobacteriaceae (CRE) are critical to protect public health. Clinicians caring for patients infected with such organisms have few, if any, therapeutic options available. CRE containing New Delhi metallo-beta-lactamase (NDM), first reported in a patient who had been hospitalized in New Delhi, India, in 2007 (1), are of particular concern because these enzymes usually are encoded on plasmids that harbor multiple resistance determinants and are transmitted easily to other Enterobacteriaceae and other genera of bacteria (2).

 

A urine specimen collected on March 4, 2012, from a patient who recently had been hospitalized in Viet Nam, but who was receiving care at a hospital in Rhode Island, was found to have a Klebsiella pneumoniae isolate containing NDM.

 

The isolate was susceptible only to tigecycline, colistin, and polymyxin B. Point-prevalence surveys of epidemiologically linked patients revealed transmission to a second patient on the hematology/oncology unit.

 

These two cases bring to 13 the number of cases of NDM reported in the United States. After contact precautions were reinforced and environmental cleaning was implemented, no further cases were identified.

 

<SNIP Lengthy Narrative On Patients, Lab Tests, and Isolation Methods>

 

Reported by

Erica E. Hardy, MD, Leonard A. Mermel, DO, Dept of Medicine, Kimberle C. Chapin, MD, Dept of Pathology, Warren Alpert Medical School of Brown Univ; Cindy Vanner, Rhode Island Dept of Health. Ekta Gupta, MD, Dept of Medicine, Boston Univ School of Medicine, Massachusetts. Corresponding contributor: Leonard A. Mermel, lmermel@lifespan.org, 401-444-2608.

Editorial Note

Since the first report in 2009, cases involving NDM-producing Enterobacteriaceae have been reported in every continent except South America and Antarctica (7). Among 29 cases in the United Kingdom, at least 17 involved patients who had traveled to India or Pakistan, among whom 14 had been hospitalized in one of those countries (8).

 

Although medical care in the Indian subcontinent was associated with many early reports, recent cases have been described involving persons who traveled to endemic regions* but were not hospitalized (7). The plasmid-carrying NDM is highly transmissible to other bacteria, and bacteria carrying NDM can colonize the gastrointestinal systems of humans for prolonged periods and can spread through contamination of water sources and environmental surfaces (7).

 

Not surprisingly, nosocomial spread also has been documented outside of the Indian subcontinent. Of 77 cases of infection or colonization with CRE containing NDM in Europe, 13 might have been hospital-acquired in Europe (9). Spread of NDM in other parts of Asia also has been reported, including four patients in South Korea without travel history (10), similar to recent reports elsewhere (7).

 

(Continue . . . )

 

 

In summary, the report offers the following:

 

What is already known on this topic?

New Delhi metallo-beta-lactamase (NDM)–producing Klebsiella pneumoniae are resistant to extended-spectrum antimicrobials, including carbapenems. The resistance mechanism is highly transmissible and its presence substantially limits treatment options. NDM-producing Enterobacteriaceae have been identified in the United States, primarily among patients with exposure to health care in endemic countries.

 

What is added by this report?

An NDM-producing organism was isolated from a patient being treated in the United States after having been hospitalized in Vietnam. Implementation of CDC-recommended carbapenem-resistant Enterobacteriaceae (CRE) control practices, including surveillance cultures of epidemiologically linked contacts, identified likely transmission to one other patient on the same ward of the U.S. hospital. Additional control measures were applied and additional surveillance and clinical cultures have not identified further transmission.

 

What are the implications for public health practice?

An aggressive approach to control of CRE, including highly transmissible carbapenemase-producing organisms, is essential to slow the spread of these organisms in the United States. In an outbreak, use of surveillance cultures to identify asymptomatic transmission potentially is an important part of these efforts.

 

 

I  wrote about this emerging public health threat less than a week ago, in NDM-1: A Matter Of Import. The following link will provide a list of some of my past blogs on the NDM-1 enzyme.

 

Without a doubt  the `go to’ blogger on all things antibiotic resistant is Maryn McKenna, author of Superbug: The Fatal Menace of MRSA. If you aren’t a regular visitor to her Superbug Blog, you should be.

 

Last March, Director-General of the World Health Organization Margaret Chan warned that the World Faces A `Post-Antibiotic Era’.

 

One where even common infections may become untreatable.

 

While we aren’t there yet, reports such as this one add to the growing concern that someday, that fear may become a reality.

»» Read More

NDM-1: A Matter Of Import

 

Inoculated MacConkey agar culture plate cultivated colonial growth of Gram-negative, small rod-shaped and facultatively anaerobic Klebsiella pneumoniae bacteria. – CDC PHIL.

 

# 6390

 

It’s been nearly 2 years since The Lancet published a study (see NDM-1: A New Acronym To Memorize)  by Walsh, Toleman, Livermore, et al. on the emergence and growing prevalence a new enzyme – dubbed NDM-1 (New Delhi metallo-ß-lactamase-1) - on the Indian sub-continent that can confer resistance to certain gram negative bacteria like E.coli and Klebsiella against a class of antibiotics called carbapenems.

 

Carbapenems are newer generation beta-lactam antibiotics (a class that includes penicillins, cephalosporins, cephamycins, and carbapenems) that are usually reserved as an antibiotic of last resort.

 

Of particular concern, this enzyme is carried by a plasmid – a snippet of portable DNA  - that can be transferred to other types of bacteria (see Study: Adaptation Of Plasmids To New Bacterial Species).

 

While the numbers were small, the authors identified a handful of patients in the UK who had recently travelled to the Indian Subcontinent and who returned with this resistant bacteria.

 

The reaction from officials out of India was both swift and disappointing. Rather than taking immediate action against a growing public health threat, they took umbrage instead.

 

They condemned of the use of `New Delhi’ in the naming of this resistance gene, called the paper a `conspiracy theory’, and issued broad denials of its prevalence in India or that medical tourism to their nation was responsible for its spread.

 

Under mounting pressure from the International community and editorializing in Indian newspapers, the Indian Health Ministry announced in October 2010 that they would impose new restrictions on the sale of 90 currently over-the-counter antibiotics.

 

But as the Deccan Chronicle reported as recently as last month, in an article called Medical body demands ban on 33 drugs in India (published May 20, 2012), little progress has been made:

 

Sale of antibiotics without prescription is rampant

Despite the government regulations restricting the sale of drugs without a prescription, medical stores continue to do so in the absence of active government monitoring. In particular, antibiotics can be obtained at medical stores just by naming them. Doctors say such an unchecked sale of antibiotics is harmful from the public's perspective.

 

Even though the policy framework of the Directorate General of Health Services seeks to regulate the unauthorised sale of antibiotics, the practice is rampant.

 

 

Six months after the first Lancet article - in April, 2011 - the same researchers published another study that found the NDM-1 enzyme in 4% of New Delhi’s sampled drinking water sources, and 30 per cent of the sewage tested.

 

The Lancet Infectious Diseases, Early Online Publication, 7 April 2011

doi:10.1016/S1473-3099(11)70059-7

Dissemination of NDM-1 positive bacteria in the New Delhi environment and its implications for human health: an environmental point prevalence study

Prof Timothy R Walsh PhD , Janis Weeks BS, David M Livermore PhD , Mark A Toleman PhD

 

 

And most alarmingly, the researchers also identified 11 new species of bacteria carrying the NDM-1 gene, including strains which cause cholera and dysentery.

 

 

Today the VOA (Voice of America) carries a report on the growing concerns over the spread of Drug Resistant bacteria across India. A problem exacerbated not only by the unregulated sale of antibiotics over the counter, but also by a lack of waste treatment facilities in that country of more than 1 billion people.

 

Concerns Mount Over India's Role In Incubating Drug-Resistant Bacteria

Kurt Achin

May 16, 2012

Medical research is once again pointing to India as a dangerous crucible of bacterial strains that resist many forms of antibiotic treatment. Cheap, under-regulated antibiotics and a severe shortfall of sanitation infrastructure fuel the problem.

 

<SNIP>

 

Unsanitary conditions in India are blamed for creating an environment for superbugs - both in emerging megacities, and in rural locations where toilet infrastructure is nearly nonexistent.

Nitya Jacob, head of water issues at New Delhi's Center for Science and Environment, co-authored a recent study called “Excreta Matters.”

"India has a capacity to treat only about a fifth of its sewage and I think about 40 percent of that capacity is concentrated in just two cities of Delhi and Bombay," said Jacob.

Superbug researcher Kumarasamy says the Indian government needs to act urgently to prevent the spread of drug-resistant diseases.

(Continue . . .)

 

More detail on the Excreta Matters study, referenced above, can be found on the Centre For Science and Environment website.

 

 

Meanwhile, as governments dither and regulations go unenforced - superbugs like NDM-1, acinetobacter, and a myriad of carbapenamases including: IMP, VIM, OXA, CMY, and most notably KPC (K. pneumoniae carbapenemase) - continue their pernicious spread around the world.

 

A story out of Edmonton, Canada last week illustrates this point, showing just how easily superbugs can be imported, and then spread:

 

Health officials admit superbug lead to death of patient at Royal Alex

Updated: Wed Jun. 06 2012 19:18:56
Julia Parrish, ctvedmonton.ca

Weeks after two types of drug resistant bacteria were brought into Edmonton by a woman who had surgery overseas, health officials have confirmed those `superbugs' lead to the death of another patient at the Royal Alexandra Hospital.

(Continue . . . )

 

 

Short of seeing an extremely high mortality influenza pandemic, I can think of no looming medical crisis more dire than the growing threat of antimicrobial resistance. The World Health Organization, the ECDC, and the CDC all consider the spread of antibiotic resistant organisms to be an extremely urgent public health concern.

 

For more on these issues, you may wish to revisit:

 

Carbapenemases Rising

Chan: World Faces A `Post-Antibiotic Era’

WHO: The Evolving Threat Of Antimicrobial Resistance

 

 

And for a far more complete (and eye-opening) discussion of antimicrobial resistance issues, I can think of no better primer than Maryn McKenna’s book SUPERBUG: The Fatal Menace of MRSA.

 

And Maryn’s SUPERBUG Blog, part of Wired Science Blogs, continues to provide the best day-to-day coverage of these issues.

»» Read More

ECDC Response Plan To Multi-Drug Resistant Gonorrhea

 

 

# 6379

 

 

Last week in WHO: Urgent Action Needed On Resistant Gonorrhea, I updated a story that Maryn McKenna and I have both written about on several occasions over the past couple of years; the worrisome rise in antibiotic-resistant gonorrhea around the globe.

 

Early last month Maryn wrote Drug-Resistant Gonorrhea: How We Lost Track and last year she penned The Clap Came Back: Multidrug-Resistant Gonorrhea, both of which are highly recommended reading.

 

You’ll find a couple of my earlier offerings here, and here.

 

Today the ECDC has released a series of reports, including a 23-page technical document with their response plan to control and manage the threat of multidrug-resistant gonorrhea in Europe.

 

 

 

Released today as well is a 41-page document called Gonococcal antimicrobial susceptibility surveillance in Europe – 2010, that finds a worrisome trend:

 

Euro-GASP 2010 identified a significant increase in the proportion of tested isolates that show decreased susceptibility to cefixime, from 4% in 2009 to 9% in 2010, using a cut-off of >0.125 mg/L. Rates of ciprofloxacin and azithromycin resistance remain high (53% and 7%, respectively).

 

Along with the two report, the ECDC has released their surveillance report Sexually transmitted infections in Europe 1990-2010, tracking the spread and prevalence of five STI’s (syphilis, congenital syphilis, gonorrhoea, chlamydia and lymphogranuloma  venereum (LGV)) across the EU over the past 2 decades.

 

Details and links follow:

 

 

 

Concerns about future treatment of gonorrhoea in Europe: ECDC issues response plan

11 Jun 2012

ECDC

With more than 32 000 cases, gonorrhoea was the second most commonly reported sexually transmitted infection (STI) in Europe in 2010. As data from the ECDC report Gonococcal antimicrobial susceptibility surveillance in Europe 2010 illustrates, gonococci have become more resistant to common agents for treatment and show reduced susceptibility to newer antibiotics. “This indicates the risk that gonorrhoea may become an untreatable disease in the near future”, stresses ECDC Director Marc Sprenger.

In response to these signals, ECDC today also publishes its Response plan to control and manage the threat of multidrug-resistant gonorrhoea in Europe.

 

Results from the European Gonococcal Antimicrobial Surveillance Programme (Euro-GASP)  show that the percentage of isolates with decreased susceptibility to the recommended drug for treatment of gonorrhoea (cefixime) rose from 4% in 2009 to 9% in 2010. Decreased susceptibility was detected in 17 countries in 2010, seven more than in the previous year.

 

“Decreasing susceptibility to recommended antimicrobials and increasing numbers of treatment failures across Europe ask for careful monitoring of the European gonococcal population as the as the loss of the current recommended treatments could result in untreatable gonorrhoea”, says ECDC Director Marc Sprenger.

Read more

• Press release "Concerns about future treatment of gonorrhoea in Europe: ECDC issues its reponse plan"
• Sexually transmitted infections in Europe 1990-2010 surveillance report
• Gonococcal antimicrobial susceptibility surveillance in Europe 2010
• Response plan to control and manage the threat of multidrug-resistant gonorrhoea in Europe

 

 

The problem of antibiotic resistance isn’t restricted to Neisseria gonorrhoeae, of course. The list of resistant bacteria is long and continues to expand, including such high profile pathogens as MRSA, NDM-1, KPC, EHEC.

 

While the end of the antibiotic era is not yet at hand, the fear is - without new drugs and the proper stewardship of the ones we already have - we may be drawing closer to that day.

 

A few of my blogs on the subject include:

 

UK: `New MRSA’ Strain Spreading

CMAJ: Local Acquisition Of NDM-1 In Ontario

India Looks For (And Finds) NDM-1

Carbapenemases Rising

WHO: The Threat Of Antimicrobial Resistance

NDM-1: A New Acronym To Memorize

 

And for a far more complete (and eye-opening) discussion of antimicrobial resistance issues, I can think of no better primer than Maryn McKenna’s book SUPERBUG: The Fatal Menace of MRSA.

»» Read More

Chan: World Faces A `Post-Antibiotic Era’

 

 

# 6226

 

World Health Organization Director-General Margaret Chan - in a keynote address to the Conference on Combating Antimicrobial Resistance this week in Copenhagen, Denmark - painted a bleak picture of the future of antibiotic availability if action is not taken.

 

The D-G’s entire remarks may be viewed on the WHO’s website at Antimicrobial resistance in the European Union and the world, but I’ve excerpted a few choice statements below, after which you’ll find a link to the World Health Organization’s latest publication on antibiotic resistance.

 

Excerpts from D-G Chan’s March 14th, 2012 speech.

 

Antimicrobial resistance is on the rise in Europe, and elsewhere in the world. We are losing our first-line antimicrobials. Replacement treatments are more costly, more toxic, need much longer durations of treatment, and may require treatment in intensive care units.

 

For patients infected with some drug-resistant pathogens, mortality has been shown to increase by around 50%. Let me give an example of what this means for a disease of global significance.

 

Among the world’s 12 million cases of tuberculosis in 2010, WHO estimates that 650,000 involved multidrug-resistant TB strains. Treatment of MDR-TB is extremely complicated, typically requiring two years of medication with toxic and expensive medicines, some of which are in constant short supply. Even with the best of care, only slightly more than 50% of these patients will be cured.

 

Many other pathogens are developing resistance to multiple drugs, some to nearly all. Hospitals have become hotbeds for highly-resistant pathogens, like MRSA, ESBL, and CPE, increasing the risk that hospitalization kills instead of cures. These are end-of-the-road pathogens that are resistant to last-line antimicrobials.

 

If current trends continue unabated, the future is easy to predict. Some experts say we are moving back to the pre-antibiotic era. No. This will be a post-antibiotic era. In terms of new replacement antibiotics, the pipeline is virtually dry, especially for gram-negative bacteria. The cupboard is nearly bare.

<SNIP>

A post-antibiotic era means, in effect, an end to modern medicine as we know it. Things as common as strep throat or a child’s scratched knee could once again kill.

 

Some sophisticated interventions, like hip replacements, organ transplants, cancer chemotherapy, and care of preterm infants, would become far more difficult or even too dangerous to undertake.

 

 

Director Chan called for greater restrictions in the use of antibiotics, and a crackdown on counterfeit drugs which not only can endanger the patients taking them, they can feed growing resistance.

 

This week the WHO released a 120 page book that provides options and strategies for combating this global threat.

 

The evolving threat of antimicrobial resistance - Options for action

Authors:
World Health Organization

Publication details

Number of pages: 120
Publication date: 2012
Languages: English
ISBN: 978 92 4 1503181

Downloads

• The evolving threat of antimicrobial resistance - Options for action
  English, pdf, 2.10Mb

Overview

Antibiotic resistance development is a natural process of adaption leading to a limited lifespan of antibiotics. Unnecessary and inappropriate use of antibiotics favours the emergence and spread of resistant bacteria. A crisis has been building up over decades, so that today common and life-threatening infections are becoming difficult or even impossible to treat. It is time to take much stronger action worldwide to avert an ever increasing health and economic burden. A new WHO publication "The evolving threat of antimicrobial resistance - Options for action" describes examples of policy activities that have addressed AMR in different parts of the world. The aim is to raise awareness and to stimulate further coordinated efforts.

 

 

As an aside, without a doubt  the `go to’ blogger on all things antibiotic resistant is Maryn McKenna, author of Superbug: The Fatal Menace of MRSA.  If you aren’t a regular visitor to her Superbug Blog, you should be.

 

While not in the same league, you’ll also find some of my humble offerings at the links below:

 

NDM-1: One Year Later

WHO Unveils 6-Point Plan To Preserve Antibiotic Effectiveness

Eurosurveillance On Antimicrobial Resistance

ECDC/EMEA: Joint Report On Resistant Bacteria

Carbapenemases Rising

WHO: The Threat Of Antimicrobial Resistance

NDM-1: A New Acronym To Memorize

»» Read More

Video: Maryn McKenna On Antibiotic Resistance

 

 

 

# 6163

 

Short of seeing a 1918-level or worse pandemic, I’ve little doubt that the rise of antibiotic resistant bacteria will be the number one public health story of the next couple of decades.

 

While MRSA was the big concern 3 or 4 years ago, today we are seeing the rise and geographic spread of NDM-1, extremely drug-resistant TB (XDR-TB), along with an expanding array of Carbapenemases  – bacteria that are resistant to the Carbapenem class of antibiotics.

 

 

Journalist, author, and everybody’s favorite scary disease girl Maryn McKenna produced a terrific book on the subject of antibiotic resistance in 2010, called SUPERBUG: The Fatal Menace Of MRSA. 

 

You can read my review of it HERE. Maryn is also the author of Beating Back The Devil, the inside story of the CDC’s Epidemic Intelligence Service.  

 

All of which puts Maryn on the top of the list of people you’d want to include in any documentary on antibiotic resistance. As it happens, UJI Films is working on exactly that; a film scheduled to be release later this year called RESISTANCE.

 

We’ve a bit of a preview this morning, by way of a 4-minute excerpt from the film featuring Maryn. You’ll also find several other short film clips on the resistancethefilm Youtube Channel, as well.

 

 

»» Read More

Lancet: Increasing Incidence Of Infectious Diseases In New Zealand

 

 

# 6158

 

 

Forty-three years ago (1969), Surgeon General of the United States William H. Stewart, famously (and as it turned out, prematurely) declared,  "The war against diseases has been won."

 

And for a time, it seemed he might be right.

  

With the advent of the Salk Vaccine in 1955, we finally had the tool with which to eradicate the last great childhood scourge in this country; Polio. By 1963, an early measles vaccine had been developed, and in the late 1970s significant improvements had been made in the existing mumps vaccine.

 

And the tremendous victory over smallpox – now vanquished from the planet for more than 3 decades – seemed only to prove the point.

 

A telling graphic from the MMWR of Dec 1999, Achievements in Public Health, 1900-1999: Control of Infectious Diseases shows the progress made during the 20th century in the battle against infectious diseases.

 

 

 

But this victory was short-lived. By 1996 you can begin to see the uptick in infectious disease deaths, after reaching its nadir in 1980.

 

Since Stewart’s pronouncement we’ve seen a Swine Flu  pandemic, a SARS epidemic, the return of the H1N1 virus in 1977 plus the emergence of previously unknown pathogens like HIV, Lyme Disease, Nipah, Hanta and Hendra (among others).

 

We’ve watched the global spread of MRSA, along with the recent arrival of of NDM-1 and other Carbapenemases that threaten the viability of our antibiotic arsenal.  Even Gonorrhea, once easily cured, threatens with new drug resistant strains.

 

And we’ve seen an explosion in dengue and chikungunya cases, the global persistence of malaria, along with outbreaks of Ebola, CCHF, and other exotic diseases.

 

Even old scourges, once thought on the way out, are showing new signs of life . . . like Pertussis, measles, and polio. Perhaps most troubling of all has been the emergence of increasingly drug resistant strains of tuberculosis.

 

On average –  researchers have discovered one new zoonotic threat a year over the past three decades.

 

 

Admittedly a lot of these emerging infectious diseases are predominantly found in developing, or under-developed countries.

 

Non-communicable diseases – like cancer, coronary artery disease, diabetes, and tobacco-related illnesses – are generally thought of as being the primary health threats in developed countries.

 

And in terms of total numbers, that holds true.

But infectious diseases are on the rise in the developed world, as is once again confirmed by the following report on a nationwide epidemiological survey of New Zealand from The Lancet.

 

 

The Lancet, Early Online Publication, 20 February 2012

doi:10.1016/S0140-6736(11)61780-7

Increasing incidence of serious infectious diseases and inequalities in New Zealand: a national epidemiological study

Dr Michael G Baker MBChB a, Lucy Telfar Barnard PhD a, Amanda Kvalsvig MBChB a, Ayesha Verrall MBChB a, Jane Zhang MSc a, Michael Keall PhD a, Nick Wilson MBChB a, Teresa Wall DPH b, Prof Philippa Howden-Chapman PhD a

Findings

Infectious diseases made the largest contribution to hospital admissions of any cause. Their contribution increased from 20·5% of acute admissions in 1989—93, to 26·6% in 2004—08. We noted clear ethnic and social inequalities in infectious disease risk. In 2004—08, the age-standardised rate ratio was 2·15 (95% CI 2·14—2·16) for Māori (indigenous New Zealanders) and 2·35 (2·34—2·37) for Pacific peoples compared with the European and other group. The ratio was 2·81 (2·80—2·83) for the most socioeconomically deprived quintile compared with the least deprived quintile. These inequalities have increased substantially in the past 20 years, particularly for Māori and Pacific peoples in the most deprived quintile.

Interpretation

These findings support the need for stronger prevention efforts for infectious diseases, and reinforce the need to reduce ethnic and social inequalities and to address disparities in broad social determinants such as income levels, housing conditions, and access to health services. Our method could be adapted for infectious disease surveillance in other countries.

 

Retrospective epidemiological analyses such as this one are always subject to a certain degree of error.

 

As this study is based on hospital admissions, it is likely that milder infections are under-represented. Coding errors, or the re-evaluation of original diagnosis codes based on the judgment of the reviewers, may further complicate matters.

 

The authors cite economic and social disparities as prime factors in the increase in infectious diseases.

 

Problems that are hardly unique to New Zealand. 

 

While almost 75% of their hospitalizations still come as the result of non-communicable diseases, the trend over the past two decades shows that infectious diseases are gaining ground.

 

Up by roughly 30% since 1989.

 

In the discussion section, the authors write:

 

The large increase in admissions for infectious diseases has important health and economic implications, and challenges prevailing views about the waning importance of infectious diseases. New Zealand seems to have the dual burden of rising non-infectious diseases, without having controlled the incidence of infectious disease.

 

The increase is equivalent to an additional 17 000 hospital admissions per year compared with the expected incidence, had the proportion of admissions caused by infectious diseases in 1989—93 continued to the present.

 

 

For more on this apparent pendulum swing back towards emerging infectious diseases, you may wish to revisit a blog I wrote more than a year ago called:

 

The Third Epidemiological Transition

»» Read More

Referral: McKenna On India’s Denial Of TDR-TB

 

 

# 6108

 

When I saw the reports on Friday about India’s Health Ministry’s attempts to downplay reports of totally drug resistant tuberculosis, I was immediately reminded of the old joke about the doctor who couldn’t cure you, but for a small fee he’d touch up your X-rays.

 

Today, Maryn McKenna takes a closer look at India’s denials (which are similar to the official reaction we saw last year over NDM-1)  in her Superbug Blog.

 

Follow the link to read:

 

 

TDR-TB: The Indian Government Denies It

• By Maryn McKenna
• January 29, 2012 

An update to the news two weeks ago of totally drug-resistant tuberculosis, TDR-TB, being identified in India (and earlier in Italy and Iran): The Indian government has announced that it doesn’t exist, and is putting pressure on the physicians who identified it to say they made a mistake.

(Continue . . . )

»» Read More

The Passing Parade Of 2011 – Pt. 2

 

 

 

# 6036

 

Over the past year I’ve posted more than 900 blogs, dozens of which looked at some of the latest research into influenza and other emerging infectious diseases.

 

Since these studies oft times make an initial splash only to get lost in the passing parade of new reports, today I’ve some brief summaries (with links back to the original blogs) on some of the research of 2011 I believe is deserving of a second look.

 

This is the second such roundup, the first one may be accessed at this link.

 

 

Last April in Lancet Study: NDM-1 In New Delhi Water Supply, we saw a report authored by Timothy Walsh, Janis Weeks , David M Livermore, and Mark A Toleman that looked for – and found – bacteria carrying the NDM-1 enzyme in New Delhi's drinking water supply.

 

We’ve a press release on this study, issued by Cardiff University, that gives the highlights of the research, but the `money quote’ (emphasis mine) buried about halfway down is:

 

Resistant bacteria were found in 4 per cent of the water supplies and 30 per cent of the seepage sites. The researchers identified 11 new species of bacteria carrying the NDM-1 gene, including strains which cause cholera and dysentery.

 

Below is a link to the Lancet study, which you can read in its entirety (a free registration is required).

 

 

The Lancet Infectious Diseases, Early Online Publication, 7 April 2011

doi:10.1016/S1473-3099(11)70059-7

Dissemination of NDM-1 positive bacteria in the New Delhi environment and its implications for human health: an environmental point prevalence study

Prof Timothy R Walsh PhD , Janis Weeks BS, David M Livermore PhD , Mark A Toleman PhD

 

Again in April, we saw research seeking to answer the question over why there was such a wide variance in death rates around the world with the 1918 Spanish influenza. 

 

In 2006, in a Lancet journal (doi:10.1016/S0140- 6736(06) 69895-4) article cited as much as a 30-fold difference in mortality rates around the world:

 

Estimation of potential global pandemic influenza mortality on the basis of vital registry data from the 1918—20 pandemic: a quantitative analysis

Christopher JL Murray , Alan D Lopez , Brian Chin , Dennis Feehan , Kenneth H Hill

Excess mortality ranged from 0·2% in Denmark to 4·4% in India. Since there was some under-registration of mortality in India, total pandemic mortality could have been even higher.

 

 

This wide disparity in mortality rates – much of it based on anecdotal accounts – has long intrigued researchers.  This new study from the Norwegian Institute of Public Health that attempts to answer some of these questions.

 

What they found was that the mortality rate varied nearly 100 fold between remote, rural regions and urban populations, and that in the more remote areas, older persons were just as susceptible to the virus as those who were younger.

 

This study appears in the Journal Epidemics.

Geography May Explain Adult Mortality from the 1918–20 Influenza Pandemic

Original Research Article
Pages 46-60
Svenn-Erik Mamelund

 

The theory that a similar H1 virus circulated prior to 1890 – and that provided some immunity to those over the age of 30 – is bolstered by this study.

 

 

Given the current flap over the H5N1 experiments conducted by Ron Fouchier in the Netherlands and Yoshihiro Kawaoka  at the University of Wisconsin (see The Biosecurity Debate On H5N1 Research) the next two studies deserve a second look as well.

 

 

Simplified Illustration of a Serial Passage Experiment. 

 

In H5N1: A Rite Of Passage we looked at how serial passage studies are conducted, and at one in particular that appeared in the Journal of Animal and Veterinary Advances that looked at increases in pathogenicity (in mice) of two H5N1 viruses after six serial passages in quail.

 

The study is called:

 

The Pathogenicity Variation of Two Quail-Origin H5N1 HPAV to BALB/c Mice after Six Passages in Quail

Hailiang Sun, Peirong Jiao, Yuqiang Cheng, Runyu Yuan, Pengfei Cui, Liming Jin, Chaoan Xin and Ming Liao

 

Another study, profiled in PNAS: Reassortment Potential Of Avian H9N2, looked at the reassortment potential of the avian H9N2 virus and H1N1. Research was done using ferrets whose respiratory physiology is considered relatively close to humans.

 

Compatibility of H9N2 avian influenza surface genes and 2009 pandemic H1N1 internal genes for transmission in the ferret model

J. Brian Kimble, Erin Sorrell,  Hongxia Shao,  Philip L. Martin, and Daniel Roberto Perez

 

(Excerpt from the abstract)

Four reassortant viruses were generated, with three of them showing efficient respiratory droplet transmission. Differences in replication efficiency were observed for these viruses; however, the results clearly indicate that H9N2 avian influenza viruses and pH1N1 viruses, both of which have occasionally infected pigs, have the potential to reassort and generate novel viruses with respiratory transmission potential in mammals.

 

 

The entire study is available online, and open access.

 

 

And in Study: Prior Antibiotic Use & MRSA In Children Canadian researchers, examining 13 years worth of data from the UK’s General Practice Research Database (GPRD), came up with what they called  a `robust association’ between a prior history of antibiotic use and rates of CA-MRSA (Community Acquired Methicillin Resistant Staph Aureus) infection in children.

The study appeared Aug. 1st  in the Archives of Pediatrics & Adolescent Medicine.

 

Antibacterial Drugs and the Risk of Community-Associated Methicillin-Resistant Staphylococcus aureus in Children

Verena Schneider-Lindner, MD, MSc; Caroline Quach, MD, MSc; James A Hanley, PhD; Samy Suissa, PhD

Arch Pediatr Adolesc Med. Published online August 1, 2011. doi:10.1001/archpediatrics.2011.143

 

What these researchers found was that while nearly half of children with MRSA in this study had no recent history of antibiotic use, the adjusted relative risk (RR) of developing MRSA was 3.5 times higher among children who had received antibiotic treatment in the previous 30-180 days before infection.

 

And that relative risk increased substantially among children who received more than one course of antibiotics.

 

To find more blogs specific to research you can use the RESEARCH quick link on my sidebar.

 

As news is often slow during the holiday season, over the next couple of weeks I plan to post one or two more retrospectives on the news and research of the year that was.

»» Read More