CDC FluView Week 52

 

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The CDC has updated their weekly FluView report, which covers influenza surveillance through December 29th, 2012.  As you can see by the ILI (Influenza-like-Illness) activity map above, much of the nation is now seeing high levels of illness.

 

Another chart from today’s interactive FluView compares the number of outpatient ILI’s being reported with previous years, including the moderately-severe 2007-08 flu season. 

 

Not only are ILI levels this year approaching that year’s peak, they are doing so 8 weeks earlier in the season.

 

 

How high ILI rates will go, and how long they will remain elevated, is something we’ll have to wait to see, but earlier today, the CDC released a statement saying:

 

. . .  based on past experience it’s likely that flu activity will continue for some time. During the past 10 influenza seasons, ILI remained at or above baseline for an average of 12 consecutive weeks . . .

 

 

Here then are some excerpts from today’s FluView Week 52 report.

 

2012-2013 Influenza Season Week 52 ending December 29, 2012

All data are preliminary and may change as more reports are received.

Synopsis:

During week 52 (December 23-29), influenza activity increased in the U.S.

• Viral Surveillance: Of 9,363 specimens tested and reported by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories, 2,961 (31.6%) were positive for influenza.
• Pneumonia and Influenza Mortality: The proportion of deaths attributed to pneumonia and influenza (P&I) was below the epidemic threshold.
• Influenza-Associated Pediatric Deaths: Two influenza-associated pediatric deaths were reported and were associated with influenza B viruses.
• Outpatient Illness Surveillance: The proportion of outpatient visits for influenza-like illness (ILI) was 5.6%; above the national baseline of 2.2%. Nine of 10 regions reported ILI above region-specific baseline levels. New York City and 29 states experienced high ILI activity; 9 states experienced moderate ILI activity; 4 states experienced low ILI activity; 6 states experienced minimal ILI activity, and the District of Columbia and 2 states had insufficient data.
• Geographic Spread of Influenza: Forty-one states reported widespread geographic influenza activity; 7 states reported regional activity; the District of Columbia reported local activity; 1 state reported sporadic activity; Guam reported no influenza activity, and Puerto Rico, the U.S. Virgin Islands, and 1 state did not report.

Novel Influenza A Virus:

No new human infections with novel influenza A viruses were reported to CDC during week 52.

A total of 312 infections with variant influenza viruses (308 H3N2v viruses, 3 H1N2v viruses, and 1 H1N1v virus) have been reported from 11 states since July 2012. More information about H3N2v infections can be found at http://www.cdc.gov/flu/swineflu/h3n2v-cases.htm.

Pneumonia and Influenza (P&I) Mortality Surveillance:

During week 52, 7.0% of all deaths reported through the 122 Cities Mortality Reporting System were due to P&I. This percentage was below the epidemic threshold of 7.1% for week 52.

Influenza-Associated Pediatric Mortality:

Two influenza-associated pediatric deaths were reported to CDC during week 52 and were associated with influenza B viruses. One death occurred during week 48 (week ending December 1) and one death occurred during week 52 (week ending December 29). This brings the total number of influenza-associated pediatric deaths reported during the 2012-2013 season to 18. Additional data can be found at http://gis.cdc.gov/GRASP/Fluview/PedFluDeath.html.

 

 

And finally, a mash-up of a chart showing Laboratory Confirmed Influenza Hospitalizations by age group, we see that (not surprisingly) those over 65, and those under the age of 4, are the hardest hit this year.

 

 

 

You can read today’s CDC full statement on this year’s flu season HERE.

»» Read More

FluView, FluWatch, And WHO Flu Surveillance Reports

Week 50 ILI activity – Source CDC FluView

 

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Regardless of your preferred type of celebration (Christmas, Hanukah, Kwanzaa, the Winter Solstice, Festivus . . .) the winter holiday season often finds us gathered together in relatively closed quarters to share presents, good times, and far too often . . . germs.

 

All of which makes this week’s FluView from the CDC, Canada’s FluWatch, and World Health Organization bi-weekly Influenza Summary of particular interest.

 

The early start to this year’s flu season continues across much of the United States, with A/H3N2 by far the predominate strain being reported. While it is a bit early to talk about the severity of this year’s flu season, historically H3N2 dominated seasons have typically produced more severe illness.

 

First stop, the CDC’s FluView Report for week 50.

 

2012-2013 Influenza Season Week 50 ending December 15, 2012

All data are preliminary and may change as more reports are received.

Synopsis:

During week 50 (December 9-15), influenza activity increased in the U.S.

• Viral Surveillance: Of 9,562 specimens tested and reported by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories in week 50, 2,709 (28.3%) were positive for influenza.
• Pneumonia and Influenza Mortality: The proportion of deaths attributed to pneumonia and influenza (P&I) was below the epidemic threshold.
• Influenza-Associated Pediatric Deaths: Two influenza-associated pediatric deaths were reported. One was associated with an influenza A (H3) virus and one was associated with an influenza A virus for which the subtype was not determined.
• Outpatient Illness Surveillance: The proportion of outpatient visits for influenza-like illness (ILI) was 3.2%; above the national baseline of 2.2%. Nine of ten regions reported ILI above region-specific baseline levels. Twelve states experienced high ILI activity, New York City and 5 states experienced moderate ILI activity; 11 states experienced low ILI activity; 22 states experienced minimal ILI activity, and the District of Columbia had insufficient data.
• Geographic Spread of Influenza: Twenty-nine states reported widespread geographic influenza activity; 12 states reported regional activity; the District of Columbia and 5 states reported local activity; 3 states reported sporadic activity; Guam reported no influenza activity, and Puerto Rico, the U.S. Virgin Islands, and 1 state did not report.

A description of surveillance methods is available at: http://www.cdc.gov/flu/weekly/overview.htm

 

The following graphic shows just how early detection of influenza has been this year (red line), compared to previous years.

 

Meanwhile, Canada’s FluWatch report indicates that influenza is beginning to ramp up in several provinces as well.

 

Overall Influenza Summary

• Influenza activity in Canada continued to increase in week 50; four regions reported widespread activity, and the majority of regions reported influenza circulation.
• A total of 1502 laboratory detections of influenza were reported, of which 96.7% were for influenza A viruses, predominantly A(H3N2).
• Thirty-one influenza outbreaks were reported: 24 in long-term-care facilities, 4 in hospitals and 3 in other facilities.
• Thirty-three paediatric influenza-associated hospitalizations were reported through the IMPACT network, all but one with influenza A
• Seventy-three hospitalizations with three deaths in adults ≥20 years of age were reported through Aggregate surveillance, all with influenza A.
• The ILI consultation rate increased compared to the previous week and is within the expected range for this time of year.

 

Virus characterization from Canada shows, like the United States, that A/H3N2 makes up the bulk of identified samples.

 

And globally, influenza rates in the Northern Hemisphere are beginning to rise, although many areas are lagging somewhat behind the numbers seen in North America. 

This from the World Health Organization.

 

Influenza update

21 December 2012 - Update number 175

 

Summary

• Many countries in the temperate regions of the northern hemisphere are now reporting elevated detections of influenza, particularly in north America.

 
• Influenza activity was still low in Europe, with co-circulating of both influenza A and B viruses. However increased influenza-like illnesses were reported in more countries than previous weeks.

• There was low, but increasing influenza activity in northern Africa and the Eastern Mediterranean regions, and sporadic detections in eastern Asia.

• Influenza in central America, the Caribbean and tropical south America continued to decline, with low levels of circulation of mainly influenza A(H3N2) and some influenza B viruses, except for Cuba and Peru, where influenza A(H1N1)pdm09 was predominant.

• Influenza activity in Sub-Saharan Africa declined to low levels, with mainly influenza B, except in Ghana, where influenza A(H1N1)pdm09 was reported.

• Influenza in most South East Asian countries was declining, except in Sri Lanka and Viet Nam.
• Influenza activity in the temperate countries of the southern hemisphere continued at inter-seasonal levels.

 

The CDC recommends a flu shot for just about everyone each year, but regardless of whether you received one, this Holiday season is a good time to hone your basic flu hygiene skills.  

 

The CDC recommends:

 

Take everyday preventive actions to stop the spread of germs.

• Cover your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash after you use it.
• Wash your hands often with soap and water. If soap and water are not available, use an alcohol-based hand rub.*
• Avoid touching your eyes, nose and mouth. Germs spread this way.
• Try to avoid close contact with sick people.
• If you are sick with flu–like illness, CDC recommends that you stay home for at least 24 hours after your fever is gone except to get medical care or for other necessities. (Your fever should be gone without the use of a fever-reducing medicine.)
• While sick, limit contact with others as much as possible to keep from infecting them.

 

As an added bonus, these healthy hygiene habits can also help protect you against the other winter time scourge, Norovirus – which, like influenza, can wreck a family holiday gathering in record time.

»» Read More

FluView Week 49

 

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Given the reports we’ve seen since the Thanksgiving holidays, it’s no surprise that this week’s CDC FluView  report shows another rise in influenza activity around the nation.

 

The most widespread activity remains in the southern tier of states.

We also learn in this update of another variant flu infection, this time from Minnesota.  

 

 

2012-2013 Influenza Season Week 49 ending December 8, 2012

All data are preliminary and may change as more reports are received.

Synopsis:

During week 49 (December 2-8), influenza activity increased in the U.S.

• Viral Surveillance: Of 7,663 specimens tested and reported by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories during week 49, 2,172 (28.3%) were positive for influenza.
• Novel Influenza A Virus: One human infection with a novel influenza A virus was reported.
• Pneumonia and Influenza Mortality: The proportion of deaths attributed to pneumonia and influenza (P&I) was below the epidemic threshold.
• Influenza-Associated Pediatric Deaths: One influenza-associated pediatric death was reported and was associated with an influenza B virus.
• Outpatient Illness Surveillance: The proportion of outpatient visits for influenza-like illness (ILI) was 2.8%, which is above the national baseline of 2.2%. Seven of ten regions reported ILI above region-specific baseline levels. Eight states experienced high ILI activity, 2 states experienced moderate ILI activity; New York City and 9 states experienced low ILI activity; 31 states experienced minimal ILI activity, and the District of Columbia had insufficient data.
• Geographic Spread of Influenza: The geographic spread of influenza in 18 states was reported as widespread; 17 states reported regional activity; the District of Columbia and 11 states reported local activity; Guam and 4 states reported sporadic activity, and Puerto Rico and the U.S. Virgin Islands did not report.

 

More than 28% of samples tested this past week were positive for influenza, with H3N2 leading the way. Here are the details on the novel flu infection.

 

Novel Influenza A Virus:

One infection with an influenza A (H3N2) variant virus (H3N2v) was reported to CDC during week 49 by Minnesota. Close contact between the case patient and swine in the week preceding illness was reported. The patient has fully recovered and no further cases have been identified in contacts of the case patient. This is the second H3N2v infection reported for the 2012-13 influenza season, which began on September 30, 2012.

 

A total of 312 infections with variant influenza viruses (308 H3N2v viruses, 3 H1N2v viruses, and 1 H1N1v virus) have been reported from 11 states since July 2012. More information about H3N2v infections can be found at http://www.cdc.gov/flu/swineflu/h3n2v-outbreak.htm.

 

While it is obvious that flu season has started early this year, it is too soon to know how severe – or prolonged – this season will turn out to be.

The CDC would like you to know, however, that it isn’t too late to get a flu shot, as the peak of influenza activity often doesn’t occur until February or March.

»» Read More

Global Flu Surveillance Updates

 

 

# 6708

 

After an uncommonly subdued 2011-2012 influenza season (see CDC: The Close Of A Mild Season), and a summer that featured an unprecedented number of variant swine flu infections (see An Increasingly Complex Flu Field) in the United States, no one is quite sure what to expect with the coming flu season.

 

Invariably, the word most often used by researchers when describing influenza is `unpredictable’.

 

Nevertheless, in order to come up with a vaccine each year, scientists must decide – 6 months in advance – what flu strains they think will be most active in the season ahead.

 

After 3 years with essentially no changes, this year’s flu vaccine formulation makes alterations to both the H3N2 and B virus strains.

 

• The H1N1 component remains essentially unchanged, with the A/California/7/2009 (H1N1)pdm09-like  still recommended.
• The old A/Perth/16/2009 (H3N2)-like virus now gives way to the A/Victoria/361/2011 (H3N2)-like virus.
• And the Victoria lineage B/Brisbane/60/2008-like virus will be replaced by a Yamagata strain; the B/Wisconsin/1/2010-like virus. 

 

The addition of these two new strains makes getting the vaccine this year all the more important, as community immunity to these recently emerging strains is likely low.

 

The vaccine die having been cast, each fall we monitor influenza activity around the world via a number of reporting tools, including:

 

• The World Health Organization’s bi-weekly global influenza update based on `data sources, including FluNet (reported by the Global Influenza Surveillance and Response System) and influenza reports from WHO Regional Offices and Member States.’
• The WHO/Europe influenza surveillance reports, which are released on a weekly basis. 
• The ECDC provides both their Weekly Influenza Surveillance Overview (WISO) along with their periodic, highly detailed Influenza virus characterisation reports
• Canada releases a weekly FluWatch report.
• And the CDC produces a detailed FluView report each week.

 

There others, of course.

 

Hong Kong’s CHP  produces an excellent Weekly Flu Express, and when it’s summer in the Northern Hemisphere we keep a close watch on the Australian  and New Zealand influenza surveillance sites.

 

Combined, these resources provide us with a pretty good - albeit `backwards looking’ - overview of flu activity. At least in North America, Europe, and parts of the Pacific Rim.

 

Note: There are plenty of areas around the world where surveillance and reporting are lacking, and so we still run the risk of being blindsided by an emerging influenza strain. 

 

During flu season I try to provide links, and highlights, to many of these flu surveillance reports each week. For now, flu activity around the world is low, but there are signs it may be increasing. 

 

From yesterday’s WHO Flu report:

 

Summary

• Many countries of the Northern Hemisphere temperate region reported increasing detections of influenza viruses, particularly in North America and Western Europe, however none have crossed their seasonal threshold for ILI/ARI consultation rates.
• Several countries in the tropical areas experienced active transmission of influenza virus in recent weeks. In the Americas, Nicaragua and Costa Rica reported mainly influenza B virus detections. In Asia, India, Sri Lanka, Nepal, and Cambodia are all reporting a mixture of all three virus subtypes.
• In Sub-Saharan Africa, Cameroon and Ethiopia have reported an increase in influenza virus detections.
• Influenza activity in the temperate countries of the Southern Hemisphere is at inter-seasonal levels. A review of the 2012 southern hemisphere influenza season was published in the Weekly Epidemiological Record (WER) 2 November 2012, vol. 87, 44 (pp. 421–436)

 

The ECDC’s latest WISO Report finds very little flu activity across Europe.

 

Weekly reporting on influenza surveillance for the 2012–13 season started in week 40/2012 in Europe.

•  In week 44/2012, all 26 reporting countries experienced low intensity of clinical influenza activity.
•  Of 279 sentinel specimens tested across 19 countries, only two were positive for influenza virus.
•  No hospitalised laboratory-confirmed influenza cases were reported.

Five weeks into the surveillance season for influenza, there has been no evidence of sustained influenza virus transmission in EU/EEA countries.

 

The story is pretty much the same in Canada, as we learn from their latest FluWatch Report.

 

Overall Influenza Summary

• Influenza activity in Canada increased slightly compared to the previous week; however overall activity still remains fairly low, with most regions of the country reporting no activity.
• In week 44, a total of 64 laboratory detections of influenza were reported; of which 91% were for influenza A viruses [71% A(H3) and 29% A(un-subtyped)].
• Six influenza outbreaks in long-term care facilities were reported in week 44.
• Eleven influenza A-associated hospitalizations were reported in week 44: 8 in adults >20 years of age, and 2 in children.
• The ILI consultation rate increased in week 44 to 21.9 per 1,000 patient visits but is within the expected level for this time of year.

 

In the United States, the CDC’s FluView Reports the beginnings of limited flu activity around the country:

012-2013 Influenza Season Week 44 ending November 3, 2012

 

 

Synopsis:

During week 44 (October 28-November 3, 2012), influenza activity increased in some areas, but overall was similar to activity last week in the United States.

• Viral Surveillance: Of 3,277 specimens tested and reported by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories during week 44, 227 (6.9%) were positive for influenza.
• Pneumonia and Influenza Mortality: The proportion of deaths attributed to pneumonia and influenza (P&I) was slightly above the epidemic threshold.
• Influenza-associated Pediatric Deaths: No influenza-associated pediatric deaths were reported.
• Outpatient Illness Surveillance: The proportion of outpatient visits for influenza-like illness (ILI) was 1.3%, which is below the national baseline of 2.2%. All 10 regions reported ILI below region-specific baseline levels. One state experienced low ILI activity; New York City and 49 states experienced minimal ILI activity, and the District of Columbia had insufficient data.
• Geographic Spread of Influenza: The geographic spread of influenza in 1 state was reported as regional; 8 states reported local activity; the District of Columbia and 33 states reported sporadic activity; Guam and 8 states reported no influenza activity, and Puerto Rico and the U.S. Virgin Islands did not report.

 

 

Many years, influenza doesn’t begin to really spread until December or even January, so the level of activity we are seeing today is probably a poor prognosticator of what we will be seeing two or three months from now.

 

Influenza, however, is notoriously unpredictable. Which makes each flu season unique, and worthy of our attention.

 

Stay tuned.

»» Read More

FluView Week 37 & Variant Flu Update

 

Variant Flu Numbers are Unchanged This week

 

 

 

# 6569

 

 

The CDC has released their weekly FluView and Variant Flu update, and for the first time in a couple of months, there are no new variant (H3N2v,H1N2v, H1N1v) cases reported to the CDC.

 

Admittedly, there could be some cases out there that are mild, and are going unreported. 

 

But no new cases is a pretty good indication that – as the CDC has been saying all along – these viruses aren’t spreading efficiently among humans.

 

As far as seasonal flu reports are concerned, they remain at very low inter-season levels.

 

2011-2012 Influenza Season Week 37 ending September 15, 2012

All data are preliminary and may change as more reports are received.

U.S. Virologic Surveillance:

WHO and NREVSS collaborating laboratories located in all 50 states and Washington, D.C. report to CDC the number of respiratory specimens tested for influenza and the number positive by influenza type and subtype. Region specific data can be found at http://gis.cdc.gov/grasp/fluview/fluportaldashboard.html.

Similarly, outpatient visits to doctors for ILI (Influenza-like Illness) are low as well.

 

Today’s data is current through September 15th, and with schools back in session, and cooler weather on its way, we shouldn’t be surprised to see flu activity pick up in the next few weeks.

»» Read More

FluView & Variant Flu Update: Week 36

 

 

 

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I’m sitting in on the AMA/IDSA Pandemic Preparedness webinar this morning, so this will be a quick update.

The CDC has released their weekly FluView and Variant Flu update, and the number of new H3N2v flu cases shows only a small increase (n=9) over last week.

 

 

 

This week’s FluView has details on these 9 cases, plus one additional H1N1v case identified in  Missouri.

 

2011-2012 Influenza Season Week 36 ending September 8, 2012

Novel Influenza A Virus:

From July 12 through September 13, 2012, a total of 305 infections with influenza A (H3N2) variant (H3N2v) viruses have been reported from ten states. This is an increase of 9 over last week’s report. Cumulative totals by state since July 15 are: Hawaii [1], Illinois [4], Indiana [138], Maryland [12], Michigan [6], Minnesota [4], Ohio [106], Pennsylvania [11], West Virginia [3], and Wisconsin [20]. Sixteen H3N2v-associated hospitalizations and one H3N2v-associated death have been reported. The vast majority of cases have occurred after prolonged swine exposure, though instances of likely human-to-human transmission have been identified. At this time no ongoing human-to-human transmission has been identified.

 

Public health and agriculture officials are investigating the extent of disease among humans and swine, and additional cases are likely to be identified as the investigations continue. Because of reporting schedules, state totals posted by CDC may not always be consistent with those reported by state health departments. If there is a discrepancy between state and CDC case counts, data from the state health department should be used as the most accurate number.

 

As a result of enhanced surveillance activities for H3N2v, one infection with an influenza A (H1N1) variant (H1N1v) virus has been detected in Missouri in a patient who became ill after contact with swine. The patient has recovered from their illness. Confirmatory testing at CDC identified H1N1v with the matrix (M) gene from the 2009 H1N1 influenza virus in specimens collected from this patient. Cases of H1N1v have been detected previously, and the current case marks the second report of H1N1v with the M gene from the 2009 H1N1 virus. This H1N1v case, in addition to the H3N2v cases outlined above and the H1N2v cases reported previously, brings the total number of variant influenza virus infections detected since July 2012 to 309.

»» Read More

CDC Variant Flu Update & FluView Week 35

Credit CDC – 9/7/12 Update

 

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The CDC has updated their case counts of human infections with the swine H3N2v virus, indicating another 8 cases have been confirmed, along with 1 additional hospitalization. 

 

 

This is the second week in a row with a relatively low increase in the number of new confirmed infections, although it should be mentioned that there remain a number of `suspected or probable cases’ that are not in today’s tally.

 

Pennsylvania, for instance, is reporting 11 confirmed cases, but lists another 30 `probable’ on their website this morning.

 

And it is likely that many mild, or sub-clinical cases simply go untested. 

 

The CDC’s Assessment of the situation reads:

 

CDC Assessment

It's possible that sporadic infections and even localized outbreaks among people with this virus will continue to occur. While there is no evidence at this time that sustained human-to-human transmission is occurring, all influenza viruses have the capacity to change and it's possible that this virus may become widespread. So far, the severity of illnesses associated with this virus in people has been similar to the severity of illnesses associated with seasonal flu virus infections. Limited serologic studies indicate that adults may have some pre-existing immunity to this virus while children do not. CDC is closely monitoring human infections with all novel influenza viruses, including H3N2v viruses, and will provide more information as it becomes available.

 

Even if you consider the gaps in surveillance, and likely under-reporting of infections from this virus, H3N2v obviously isn’t spreading anything like the H1N1pdm09 virus did during its debut in the spring of 2009.

 

To put this into perspective, we are roughly 7 weeks since the first clusters began to appear in the Midwest (July 12th, 2012), and we are (just barely) below 300 confirmed cases across 10 states. 

 

The following blast from the past shows the number (and wide geographic spread) of 2009 H1N1 virus detections being reported to the World Health Organization in early June 2009, roughly 7 weeks after it was first detected. 

 

Influenza A(H1N1) - update 45

8 June 2009 -- As of 06:00 GMT, 8 June 2009, 73 countries have officially reported 25,288 cases of influenza A(H1N1) infection, including 139 deaths.

There were, by the way, plenty of gaps in testing and surveillance for the H1N1 virus back in 2009 as well.  The numbers reported above are generally considered to be an undercount.

 

While the H3N2v virus may very well develop `legs’ over time - and eventually pose a larger public health threat - right now it obviously isn’t spreading anything like its H1N1pdm cousin did.

 

Today’s FluView Report has a summary of the novel H3N2v activity and the three H1N2v cases reported last week (see Minnesota Reports Swine H1N2v Flu)

 

 

2011-2012 Influenza Season Week 35 ending September 1, 2012

All data are preliminary and may change as more reports are received.

Novel Influenza A Virus:

From July 12 through September 6, 2012, a total of 296 infections with influenza A (H3N2) variant (H3N2v) viruses have been reported from ten states. This is an increase of 8 over last week’s report. Cumulative totals by state since July 15 are: Hawaii [1], Illinois [4], Indiana [138], Maryland [12], Michigan [5], Minnesota [2], Ohio [102], Pennsylvania [11], West Virginia [3], and Wisconsin [18]. Sixteen H3N2v-associated hospitalizations and one H3N2v-associated death have been reported. The vast majority of cases have occurred after prolonged swine exposure, though instances of likely human-to-human transmission have been identified. At this time no ongoing human-to-human transmission has been identified.

 

<SNIP>

As a result of enhanced surveillance activities for H3N2v, three infections with influenza A (H1N2) variant (H1N2v) virus have been detected in Minnesota in patients who became ill after contact with swine. One patient was hospitalized, but all have recovered from their illness. Confirmatory testing at CDC identified H1N2v with the matrix gene from the 2009 H1N1 influenza virus in specimens collected from all three patients. Although cases of H1N2v have been detected previously, the current cases mark the first reports of H1N2v with the matrix gene from the 2009 H1N1 virus.

 

Otherwise, surveillance of flu activity around the country shows very little activity, despite the scattered reports of H3N2v in the Midwest.

 

 

And the 122 Cities Pneumonia & Influenza mortality surveillance continues to indicate deaths are running well below the seasonally adjusted epidemic level.

 

Pneumonia and Influenza (P&I) Mortality Surveillance:

During week 35, 5.6% of all deaths reported through the 122-Cities Mortality Reporting System were due to P&I. This percentage was below the epidemic threshold of 6.5% for week 35.

 

 

With cooler weather on the way, another 6 to 8 weeks of state and county fairs (mostly in the south), and schools now going back into session, we’ll be watching closely to see if this two-week decline in new cases is a temporary lull, or a sustained trend.

 

Stay tuned.

»» Read More

CDC Updates H3N2v Numbers, 1 Death Reported

# 6529

 

 

The CDC has posted their weekly update on the emerging H2N2v (variant) flu virus, and there’s good news and sad news:

 

The good news is that only a dozen additional cases have been confirmed, and no additional states have reported infections. It is highly likely, however, that some number of cases are going unreported.

 

That said, were this virus spreading in an efficient and sustained manner in the human population, we would expect to see a lot more cases being reported. 

 

 

The sad news – not unexpectedly – is that a death has finally been attributed to this variant virus.

 

This was pretty much Inevitable, given that this virus has been described as being roughly equivalent in virulence to seasonal flu, which claims thousands of lives each year.

 

 

The CDC reports:

 

Influenza A (H3N2) Variant Virus Outbreaks

Today, CDC is reporting 12 additional cases of H3N2 variant virus (H3N2v) infection, as well as the first H3N2v-associated death, which was reported by the state of Ohio. The death occurred in an older adult with multiple underlying health conditions who reportedly had direct exposure to pigs in a fair setting.

 

While limited person-to-person spread of this virus has been detected and likely continues to occur sporadically, no sustained community transmission has been found. CDC is monitoring this situation and working with states to respond to these evolving outbreaks. The agency continues to urge people at high risk from serious flu complications to stay away from pigs and pig arenas at fairs this summer.

 

<SNIP>

 

The 12 new cases reported this week are from the states of Minnesota (1), Ohio (3), Pennsylvania (1), and Wisconsin (7). Cumulative totals for 2011 and 2012 by state are available in the H3N2v case count table.

(Continue . . . .)

 

Graphs from today’s FluView report also illustrate the drop in new cases, and provides some detail on the level of H3N2v activity.

 

2011-2012 Influenza Season Week 34 ending August 25, 2012

All data are preliminary and may change as more reports are received.

U.S. Virologic Surveillance:

WHO and NREVSS collaborating laboratories located in all 50 states and Washington, D.C. report to CDC the number of respiratory specimens tested for influenza and the number positive by influenza type and subtype. Region specific data can be found at http://gis.cdc.gov/grasp/fluview/fluportaldashboard.html.

Novel Influenza A Virus:

From July 12 through August 30, 2012, a total of 288 infections with influenza A (H3N2) variant (H3N2v) viruses have been reported in ten states (Hawaii [1], Illinois [4], Indiana [138], Maryland [12], Michigan [5], Minnesota [2], Ohio [101], Pennsylvania [7], West Virginia [3], and Wisconsin [15]). So far during the current outbreaks, 15 confirmed cases have been hospitalized as a result of their illness; one death has occurred.

 

The vast majority of cases have been associated with swine exposure though likely instances of human-to-human transmission have been identified. At this time no ongoing human-to-human transmission has been identified.

 

Public health and agriculture officials are investigating the extent of disease among humans and swine, and additional cases are likely to be identified as the investigation continues. Because of reporting deadlines, the state totals reported by CDC may not always be consistent with those reported by state health departments. If there is a discrepancy between these two counts, data from the state health departments should be used as the most accurate number.

 

 

The concern here is less about the public health threat this variant virus poses today - and more about the threat it could pose in the future - if it better adapts to transmit between humans.

 

Each human infection, unfortunately, gives the virus another opportunity to adapt, making prevention of infection all the more important.

 

Meanwhile, we continue to watch these weekly tally’s with considerable interest, looking for any indications that something has changed.

»» Read More

H3N2v Update: CDC Reports 52 New Cases, Limited H2H Transmission

 

Credit Wikipedia

 

# 6517

 

 

The mantra of the CDC over the past few weeks regarding the H3N2v flu virus is that sustained and efficient transmission between humans has not been detected.  They have allowed the possibility, however, that some limited person-to-person transmission may have occurred.

 

And today’s numbers, indicating just 52 new cases reported over the past week, continues to support that analysis.

 

While some cases may be going unrecorded, this total is lower than one would expect to see if the virus were being readily transmitted.

Good news for now, but with the caveats that surveillance by definition is a look backwards in time – not ahead - and this virus is still learning about human physiology.

 

Given enough opportunities - H3N2v could one day adapt to become a more formidable human pathogen.

 

Here then are some excerpts from today’s CDC FluView Report and their weekly H3N2v update:

 

2011-2012 Influenza Season Week 33 ending August 18, 2012

 
 

Novel Influenza A Virus:

From July 12 through August 23, 2012, a total of 276 infections with influenza A (H3N2) variant (H3N2v) viruses have been reported in ten states (Hawaii [1], Illinois [4], Indiana [138], Maryland [12], Michigan [5], Minnesota [1], Ohio [98], Pennsylvania [6], West Virginia [3], and Wisconsin [8]). So far during the current outbreaks, 13 confirmed cases have been hospitalized as a result of their illness; no deaths have occurred. The vast majority of cases have been associated with swine exposure though three likely instances of human-to-human transmission have been identified. At this time no ongoing human-to-human transmission has been identified. Public health and agriculture officials are investigating the extent of disease among humans and swine, and additional cases are likely to be identified as the investigation continues. Because of reporting deadlines, the state totals reported by CDC may not always be consistent with those reported by state health departments. If there is a discrepancy between these two counts, data from the state health departments should be used as the most accurate number.

 

 

 

H3N2v Update: New Cases Reported, Limited Person-to-Person Transmission Detected

August 24, 2012 -- Today, 52 additional cases of H3N2v are being reported, bringing the total number of such infections since July 2012 in the United States to 276 across 10 states. Investigations into H3N2v cases indicate that the main risk factor for infection is exposure to pigs, mostly in fair settings; however, CDC also is reporting three instances of likely human-to-human spread of this virus during the current outbreaks. Found in pigs in 2010 and first detected in humans in July 2011, this H3N2 variant virus appears to be more transmissible from pigs to people than other variant viruses. The Centers for Disease Control and Prevention (CDC) is working with states to respond to this evolving situation and continues to monitor the situation closely.

 

According to CDC’s Dr. Joseph Bresee “limited human-to-human spread of this virus has been seen in the past, but the H3N2v virus has not previously -- and is not now -- spreading easily from person-to-person.” According to Bresee, “Most cases are occurring in children who are exhibiting pigs, or helping to exhibit pigs and have occurred after a lot of very close contact with pigs over a relatively long period of time.” Dr. Bresee is Chief of the Epidemiology and Prevention Branch in CDC’s Influenza Division.

 

The 52 new cases reported this week are from the states of Illinois (1), Maryland (12), Michigan (4), Minnesota (1), Ohio (26), Pennsylvania (2), and Wisconsin (6). This is the first report of H3N2v with the pandemic M gene from Maryland and Minnesota. The 6 cases in Maryland are reported to have had contact with pigs prior to their illness. The one case in Minnesota was confirmed following a visit to a live animal market where pigs were present. Cumulative totals for 2011 and 2012 by state are available in the H3N2v case count table. The remaining cases being reported this week are associated with exposure to pigs at fairs.

 

The three instances of likely person-to-person spread of H3N2v were recently identified during investigations of cases and their household contacts and are not epidemiologically linked to one another. In all three cases, transmission is thought to have occurred from one person to another person without further spread to additional people. Each of these three instances of likely person-to-person spread happened between 2 people living in the same household, with the initial infection in each household being associated with pig exposure at an agricultural fair.

 

“We’re not particularly surprised to see what looks like limited human-to-human transmission,” says Bresee. Limited human-to-human spread has been seen in the past, both with this variant virus as well as other variant viruses. “It’s clear though,” Bresee adds, “that this virus is much better able to spread to people. It’s reassuring that we are seeing most cases in people with prolonged contact with pigs and that we are not seeing any sustained community transmission, but this situation definitely warrants our close attention,” says Bresee.

 

CDC is monitoring for changes in the virus and potential person-to-person transmission of H3N2v. This week CDC updated its guidance to states for enhanced surveillance for influenza-like-illness (ILI) in all people, including people reporting pig exposure. So far, genetic analysis of the viruses submitted to CDC show that all viruses are nearly identical, and very similar to the H3N2v viruses found in 2011.

 

Illness associated with this virus so far continues to be mostly mild with symptoms similar to seasonal flu. Like seasonal flu, however, serious illness with H3N2v infection is possible. To date, 13 hospitalizations have occurred, but all patients have recovered. Last week CDC issued information for clinicians on H3N2v; guidance which underscores the importance of rapid antiviral treatment of H3N2v virus infections in high risk patients.

 

 

The CDC makes the following recommendations to limit the risks of infection from the H3N2v virus.

 

Preventive Actions

CDC Recommendations For People At High Risk:

• If you are at high risk of serious flu complications and are going to a fair where pigs will be present, avoid pigs and swine barns at the fair this year. This includes children younger than 5 years, people 65 years and older, pregnant women, and people with certain long-term health conditions (like asthma, diabetes, heart disease, weakened immune systems, and neurological or neurodevelopmental conditions).

If you are not at high risk, take these precautions:

• Don’t take food or drink or eat, drink or put anything in your mouth in pig areas.
• Don’t take toys, pacifiers, cups, baby bottles, strollers, or similar items into pig areas.
• Wash your hands often with soap and running water before and after exposure to pigs. If soap and water are not available, use an alcohol-based hand rub.
• Avoid close contact with pigs that look or act ill.
• Take protective measures if you must come in contact with pigs that are known or suspected to be sick. This includes minimizing contact with pigs and wearing personal protective equipment like protective clothing, gloves and masks that cover your mouth and nose when contact is required.
• To further reduce the risk of infection, minimize contact with pigs and swine barns.

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H3N2v: CDC Update & ECDC Risk Assessment

 

 

# 6500

 

Friday means the weekly CDC FluView report is out, and right now, the only flu to talk about in the U.S. is H3N2v. We also have a risk assessment from the ECDC  today on this emerging virus, and another state (Pennsylvania) to add to the list of places reporting human infections (4 confirmed, 6 suspected). 

 

First stop though, is the CDC’s H3N2v update page, where the latest state totals are listed. Since last week Pennsylvania, Wisconsin, West Virginia, and Michigan have reported their first cases.

 

 

There you will also find the CDC’s assessment of this virus, and the risks it currently poses to the public’s health.

 

CDC Assessment

It's possible that sporadic infections and even localized outbreaks among people with this virus will continue to occur. While there is no evidence at this time that sustained human-to-human transmission is occurring, all influenza viruses have the capacity to change and it's possible that this virus may become widespread. So far, the severity of illnesses associated with this virus in people has been similar to the severity of illnesses associated with seasonal flu virus infections. Limited serologic studies indicate that adults may have some pre-existing immunity to this virus while children do not. CDC is closely monitoring human infections with all novel influenza viruses, including H3N2v viruses, and will provide more information as it becomes available.

 

 

An assessment that is in-line with the latest risk assessment from the ECDC, which finds the risk to public health from this virus to be very low at this time.

 

ABSTRACT

Following recent increased reporting of human infections in the US with an influenza A(H3N2) variant virus of swine origin (A(H3N2)v), ECDC has updated its risk assessment. It concludes that the swine-origin influenza A(H3N2)v viruses do not currently pose a serious risk to human health in general and Europe in particular. Should increased pathogenicity and/or transmissibility be acquired this assessment will be revised as well as further developments presented on the ECDC web-site.

 

Conclusions and recommendations

The swine-origin influenza A(H3N2)v viruses do not currently pose a serious risk to human health in general and Europe in particular. Should increased pathogenicity and/or transmissibility be acquired this assessment will be revised as well as further developments presented on the ECDC web-site. 

 

 

Beyond a few hundred cases of H3N2v, flu activity around the country remains at inter-seasonal low levels, as illustrated by these FluView Reports.

 

 

Today’s FluView contained the following statement on H3N2v.

 

Novel Influenza A Virus:

Novel Influenza A Virus: From July 12 through August 16, 2012, a total of 224 infections with influenza A (H3N2) variant (H3N2v) viruses have been reported in eight states (Hawaii [1], Illinois [3], Indiana [138], Michigan [1], Ohio [72], Pennsylvania [4], West Virginia [3], and Wisconsin [2]). So far during the current outbreaks, eight confirmed cases have been hospitalized as a result of their illness; no deaths have occurred. At this time no ongoing human-to-human transmission has been identified. Public health and agriculture officials are investigating the extent of disease among humans and swine, and additional cases are likely to be identified as the investigation continues. Because of reporting deadlines, the state totals reported by CDC may not always be consistent with those reported by state health departments. If there is a discrepancy between these two counts, data from the state health departments should be used as the most accurate number.

 

CDC is required to report all cases of human infection with novel (non-human) influenza viruses – including influenza viruses of swine origin – to the World Health Organization (WHO) as part of the International Health Regulations (IHR). Domestically, CDC reports these cases in this report and on its website. Early identification and investigation of human infections with novel influenza A viruses is critical in order to evaluate the extent of the outbreak and possible human-to-human transmission. Additional information on influenza in swine, variant influenza infection in humans, and strategies to interact safely with livestock can be found at http://www.cdc.gov/flu/swineflu/influenza-variant-viruses-h3n2v.htm.

 

 

While it may not serve to sell newspapers or drive web traffic, this virus is a long way from being any kind of serious public health threat. 

 

That could change over time, of course.

 

Viruses are constantly evolving, and what was true yesterday about H3N2v may not be true next week, or next year. 

 

So we’ll continue to watch these outbreaks with interest. Not because they necessarily portend a pandemic, but because they can teach us a lot about how variant viruses develop and spread.

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CDC: The Close Of A Mild Season

 

# 6346

 

The last FluView report of the 2011-2012 flu season has been issued by the CDC, along with a report that summarizes the end to what was an unusually late, and exceptionally mild flu season. 

 

Graph of a remarkably mild flu influenza season.

 

This from the CDC’s summary.

 

2011-2012 Flu Season Draws to a Close

Last full FluView posted May 25, 2012 Shows U.S. Influenza Activity at Summer Levels

A Late and Mild Flu Season

May 25, 2012 – Today the Centers for Disease Control and Prevention issued the final full influenza surveillance report for the 2011-2012 season. The report – titled “FluView” – shows that influenza activity in the United States is minimal across most of the country, wrapping up a season that began late and was mild compared to most previous seasons for which surveillance data is available. In fact, the season set a new record for the lowest and shortest peak for influenza-like-illness since this type of surveillance began.

 

Influenza-like-illness (ILI) in the United States typically begins to increase in late December or early January and peaks in February most commonly. This season, ILI remained low through February and did not exceed baseline – and then only slightly -- until mid-March. ILI stayed above baseline for just one week in March and did not exceed baseline again. According CDC’s Dr. Joseph Bresee, “This is the first time since CDC started this kind of influenza-like-surveillance (ILI) that the percentage of patient visits for ILI was elevated for only one week of the season.” Dr. Bresee is Chief of the Epidemiology and Prevention Branch in CDC’s Influenza Division. In past seasons, ILI has remained above baseline for between 8 and 20 weeks, with an average of 13 weeks at or above baseline each season since this type of surveillance began in 1997-1998. Bresee adds, “In terms of ILI, this not only the shortest time we were above baseline, but it’s also the lowest ‘peak’ ever recorded.” The graph below compares ILI from five different seasons, including the current season (2011-2012), the 2009 H1N1 pandemic season, a ‘moderately severe’ flu season (2007-2008), as well as a season classified as ’moderate’ in severity (2002-03).

For a more detailed view of the graphic, please click on the image or visit ILI Weekly National Summary detail.

(Continue . . . )

 

The CDC has also announced several new interactive data display tools, which show various datasets over time.

 

Interactive Web Tools

A new interactive web application in “FluView,” displays information – from this season and previous season’s – related to flu-related pediatric deaths. Other interactive tools display ILI over time and ILI and laboratory data on a national and regional level over time.

 

 

Interactive View of Pediatric Deaths related to Influenza

 

As to why this current flu season has been so mild, solid answers are hard to find. The CDC’s Dr. Joseph Bresee is quoted as saying:

 

“The reason for the mildness and lateness of the season isn’t certain, but it’s likely that there were a number of contributing factors, including a mild winter, the fact that most of the influenza viruses circulating this season were similar to those that have circulated for the past two seasons and the fact that most circulating viruses were similar to the viruses that the 2011-2012 vaccine was designed to protect against.” The low levels of influenza virus “drift” (change) for two consecutive years and “steadily increasing influenza vaccination coverage in the country likely contributed to broad levels of immunity in the population,” says Bresee.

 

 

Whatever the cause, it’s probably too much to hope for a repeat next year. Which makes getting the flu shot when it becomes available in the fall, the smart thing to do.

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