Shaken, And Hopefully Stirred

Location of last weekend’s Earthquake - USGS

 

# 6691

 

The 7.7 quake last weekend (see Haida Gwaii Quake & Tsunami Advisories) off the northern coast of British Columbia was a not-so-gentle reminder that the Pacific Northwest is not immune to strong earthquakes.

 

While the San Andreas fault in Southern California is better known, the Cascadia fault that runs along the Northern California, Oregon, Washington, and B.C. coast (well south of last week’s quake) is believed capable of generating a massive earthquake/tsunami combination, much like we saw with Japan’s Great Earthquake of 2011.

 

Based primarily on the fact that it’s happened before.

 

Last year, in Just A Matter Of Time, I described how records showed that 312 years ago an orphan tsunami struck the coast of Japan, without an accompanying earth tremor being felt.

 

It’s origin remained a mystery for years, but today scientists - looking at sediment levels and tree growth rings – can easily see evidence of a great quake (8.7-9.2)  occurring along the Cascadia fault at that time.

 

 

Although at the time of my previous blog there was evidence of a series of major quakes along this fault line, going back thousands of years, in August of 2012 a new study was published that suggests another quake is `overdue’.

 

The study, was published by the USGS, and may be read at the link below:

 

Turbidite Event History—Methods and Implications for Holocene Paleoseismicity of the Cascadia Subduction Zone

By Chris Goldfinger, C. Hans Nelson, Ann E. Morey, Joel E. Johnson, Jason R. Patton, Eugene Karabanov, Julia Gutiérrez-Pastor, Andrew T. Eriksson, Eulàlia Gràcia, Gita Dunhill, Randolph J. Enkin, Audrey Dallimore, and Tracy Vallier

 

 

For those who would prefer not to wade through the paper, we have a press release from the Oregon State University, that explains the findings.  Excerpts follow:

 

13-year Cascadia study complete – and earthquake risk looms large

8-1-12

CORVALLIS, Ore. – A comprehensive analysis of the Cascadia Subduction Zone off the Pacific Northwest coast confirms that the region has had numerous earthquakes over the past 10,000 years, and suggests that the southern Oregon coast may be most vulnerable based on recurrence frequency.

 

Written by researchers at Oregon State University, and published online by the U.S. Geological Survey, the study concludes that there is a 40 percent chance of a major earthquake in the Coos Bay, Ore., region during the next 50 years. And that earthquake could approach the intensity of the Tohoku quake that devastated Japan in March of 2011.

 

“The southern margin of Cascadia has a much higher recurrence level for major earthquakes than the northern end and, frankly, it is overdue for a rupture,” said Chris Goldfinger, a professor in OSU’s College of Earth, Ocean, and Atmospheric Sciences and lead author of the study. “That doesn’t mean that an earthquake couldn’t strike first along the northern half, from Newport, Ore., to Vancouver Island.

 

“But major earthquakes tend to strike more frequently along the southern end – every 240 years or so – and it has been longer than that since it last happened,” Goldfinger added. “The probability for an earthquake on the southern part of the fault is more than double that of the northern end.”

 

The publication of the peer-reviewed analysis may do more than raise awareness of earthquake hazards and risks, experts say. The actuarial table and history of earthquake strength and frequency may eventually lead to an update in the state’s building codes.

(Continue . . . )

 

 

Since we can’t prevent earthquakes, and accurate prediction of when they will occur is beyond our technology, our only recourse is to prepare for them.

 

In January of 2011 I profiled a Washington state based preparedness educator Carol Dunn, who maintains an excellent website on the hazards faced by those living in the Pacific Northwest called 2Resilience.

 

You’ll find numerous resources geared for professional first responders, citizen volunteers, and families, individuals, and businesses looking to improve their level of knowledge and preparedness.

 

Many of us who follow @Caroldn on Twitter find her dedication and enthusiasm on preparedness issues to be quite contagious.  And if your interests lie in that direction I’d certainly recommend you include her feed.

 

Another resource I strongly recommend is Shakeout.org, which promotes yearly earthquake drills and education around the country.

 

For more on how you can prepare for `the big one’ (even if you live someplace other than Los Angeles), I would recommend you download, read, and implement the advice provided by the The L. A. County Emergency Survival Guide.

 

And to become better prepared as an individual, family, business owner, or community to deal with these types of disasters: visit the following preparedness sites.

 

FEMA http://www.fema.gov/index.shtm

READY.GOV http://www.ready.gov/

AMERICAN RED CROSS http://www.redcross.org/

 

Because no matter where you live, its just a matter of time before the next disaster strikes.

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Four Million Fears, BC

 

 

# 6303

 

 

One of the recurring themes in this blog is that disasters can strike anytime, and just about anywhere. For most people, that remains an abstract concept and hard to accept possibility.

 

Which is why it is useful to identify local hazards and point them out to the residents. Here in Florida, talk of hurricane preparedness begins every year several weeks before the season starts.

 

Fellow blogger Crawford Kilian (aka Crof) has a nice feature in The Tyee today, that looks at five disasters that – given enough time – are likely to impact the roughly four million residents of British Columbia.

 

 

Five Disasters to Befall BC

TYEE LIST #12: Earthquakes, pandemics, solar flares; a calamitous pall hangs over our province.

By Crawford Kilian, Today, TheTyee.ca

Natural disasters are exciting when they happen to other people, but we'd rather not think about undergoing them ourselves. As Woody Allen famously observed, "I'm not afraid of death; I just don't want to be there when it happens."

Still, we should make our wills even when we're in our prime, and we should bear in mind that some events are so extensive that we will indeed be there when they happen. So let us consider five certain disasters B.C. will face at some point in the future.

(Continue . . . )

 

 

As always, Crof provides an interesting and informative read.

 

As if to drive home the point, in the overnight hours the island of Vancouver has experienced no fewer than three  4.0+ magnitude quakes.  Not enough to do any real damage – but a not so gentle reminder that millions of us stand on shaky ground.

 

For another take on all of this - last year in Just A Matter Of Time - I took a long look at the devastating potential of a Vancouver earthquake – tsunami combination.

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6.7 Magnitude Quake Off Vancouver Island

 

 

# 5829

 

In the past hour a fairly shallow (26km) 6.7 Magnitude quake struck off the northern coast of Vancouver Island. So far, there are no reports of damage and no destructive tsunami is expected to have been generated.

 

 

 

 

It is worth noting that British Colombia will hold their yearly earthquake drill, The Great British Columbia ShakeOut, on October 20, 2011.

 

The Pacific Northwest is considered at greater risk of seeing a devastating 8.0+ earthquake than is southern California.  Last July I wrote a blog about the potential of this region seeing such a disaster, which included several videos simulating the damage that might result.

 

Those interested may wish to revisit:

 

Just A Matter Of Time

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A Fungus Among Us

 

 

# 4518

 

 

When we think about infectious diseases we are apt to think first about viral or bacterial infections.  But fungal Infections, or mycoses, can cause serious illness or injury as well.

 

When I moved to Arizona in 1975 to work as a paramedic, one of the first things I learned about was Coccidioidomycosis, also known as Valley Fever, which is endemic in our southwestern states and much of northern Mexico.  

 

   

 

The illness is caused by the inhalation of one of two soil borne fungi, Coccidioides immitis or C. posadasii., that become airborne when the earth is disturbed by farming, construction, or windstorms.

 

Most of the people who live in these areas have been exposed and inoculated with the spores, and either developed brief silent or sub-clinical infections, or perhaps experienced mild flu-like symptoms. 

 

Severe disease – although rare – can occur.  Sometimes even years after initial exposure. 

 

In 2001, Arizona alone reported more than 2200 cases of Coccidioidomycosis (MMWR 52(06);109-112).

 

Another mycotic disease called Histoplasmosis is found in the Ohio River Valley, and along the lower Mississippi river, and it too can cause severe disease in rare instances.

 

In the case of Histoplasmosis, the causative agent is Histoplasma capsulatum, which is found in bird and bat droppings.   These can become airborne when these droppings dry out and are picked up by the wind. 

 

Neither of these diseases are communicable. They are acquired from the environment. They are not transmitted from one person to another.

 

Those with weakened immune systems are generally most at risk of seeing serious complications from these fungal infections, although even healthy people are occasionally stricken. 

 

 

I mention these two endemic fungal diseases so as to help put the following report into perspective. 

 

Over the past 10 years, a new fungal threat has emerged in the Pacific Northwest.  Cryptococcus gattii, a tropical fungus common in Australia and New Guinea, showed up unexpectedly on Vancouver Island in 1999 –  eventually infecting more than 200 people.

 

Since then, the fungus has expanded its range, appearing in British Columbia, Washington, and Oregon. Of particular concern, a more pathogenic strain – one that apparently infects healthy individuals and has a higher mortality rate, has recently been identified.

 

This fungus – a yeast really – is found in a number of species of trees (primarily Douglas fir & Western hemlock) and in the soil.  It can be spread by the wind, particularly during the warmer summer months.

 

This fungus has a wide host range, having been found to infect humans along with cats, dogs, porpoises, ferrets, llamas, elk, alpacas, and sheep.

 

While all of this sounds dire, one must remember that hundreds of thousands of people in the Pacific Northwest have likely been exposed to these airborne spores over the past 10 years. 

 

So far, only about 250 people in the region have developed identifiable illness during that time.  As a broad-based public health hazard, for now at least, this ranks fairly low. 

 

For epidemiologists, environmental scientists, and mycologists, however . . .  this is fascinating stuff indeed.

 

We’ll start off with the Reuters story, which provides a brief overview:

 

Potentially deadly fungus spreading in US, Canada

22 Apr 2010 22:21:58 GMT

Source: Reuters

* Fungus is unique genetic strain

* Climate change may aid its spread

WASHINGTON, April 22 (Reuters) - A potentially deadly strain of fungus is spreading among animals and people in the northwestern United States and the Canadian province of British Columbia, researchers reported on Thursday.

 

The airborne fungus, called Cryptococcus gattii, usually only infects transplant and AIDS patients and people with otherwise compromised immune systems, but the new strain is genetically different, the researchers said.

 

"This novel fungus is worrisome because it appears to be a threat to otherwise healthy people," said Edmond Byrnes of Duke University in North Carolina, who led the study.

(Continue . . .)

 

 

For the hard core science geek details on this emerging pathogen you may wish to read the complete study published in PLoS Pathogens.

 

Fair warning, while fascinating, this isn’t `light reading’.

 

I’ve reproduced the author’s summary (reparagraphed for readability) below.

 

Emergence and Pathogenicity of Highly Virulent Cryptococcus gattii Genotypes in the Northwest United States

: Byrnes EJ III, Li W, Lewit Y, Ma H, Voelz K, et al. (2010) Emergence and Pathogenicity of Highly Virulent Cryptococcus gattii Genotypes in the Northwest United States. PLoS Pathog 6(4): e1000850. doi:10.1371/journal.ppat.1000850

 

Emerging and reemerging infectious diseases are increasing worldwide and represent a major public health concern. One class of emerging human and animal diseases is caused by fungi.

 

In this study, we examine the expansion on an outbreak of a fungus, Cryptococcus gattii, in the Pacific Northwest of the United States. This fungus has been considered a tropical fungus, but emerged to cause an outbreak in the temperate climes of Vancouver Island in 1999 that is now causing disease in humans and animals in the United States.

 

In this study we applied a method of sequence bar-coding to determine how the isolates causing disease are related to those on Vancouver Island and elsewhere globally.

 

We also expand on the discovery of a new pathogenic strain recently identified only in Oregon and show that it is highly virulent in immune cell and whole animal virulence experiments. These studies extend our understanding of how diseases emerge in new climates and how they adapt to these regions to cause disease.

 

Our findings suggest further expansion into neighboring regions is likely to occur and aim to increase disease awareness in the region.

 

 

 

 

A couple of months ago the CDC’s Journal of Emerging Infectious Diseases published a research article on the epidemiology of the spread of C. gattii  in British Columbia. 

 

 

Volume 16, Number 2–February 2010

Research

Epidemiology of Cryptococcus gattii, British Columbia, Canada, 1999–2007

Eleni Galanis and Laura MacDougall
Author affiliations: British Columbia Centre for Disease Control, Vancouver, British Columbia, Canada (E. Galanis, L. MacDougall); and University of British Columbia, Vancouver (E. Galanis)

 

Abstract
British Columbia, Canada, has the largest reported population of Cryptococcus gattii–infected persons worldwide. To assess the impact of illness, we retrospectively analyzed demographic and clinical features of reported cases, hospitalizations, and deaths during 1999–2007.

 

A total of 218 cases were reported (average annual incidence 5.8 per million persons). Most persons who sought treatment had respiratory illness (76.6%) or lung cryptococcoma (75.4%). Persons without HIV/AIDS hospitalized with cryptococcosis were more likely than those with HIV/AIDS to be older and admitted for pulmonary cryptococcosis.

 

The 19 (8.7%) persons who died were more likely to be older and to have central nervous system disease and infection from the VGIIb strain. Although incidence in British Columbia is high, the predominant strain (VGIIa) does not seem to cause greater illness or death than do other strains.

 

Further studies are needed to explain host and strain characteristics for regional differences in populations affected and disease outcomes.

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