Recent flooding in Australia (don't forget that it's summer there) has been followed by a spike in the number of Murray Valley encephalitis cases. MVEV is an arbovirus of flaviviridae (genus flavivirus, along with Yellow Fever, West Nile, and Dengue) and is transmitted by mosquitoes. In addition, MVEV persists in the bird population year round as a reservoir.
MVEV appears to cause no clinical presentation in the vast majority of infected individuals; however, a very small number of individuals develop encephalitis. According to the Health section of the New South Wales website, very young infants, travelers, and immigrants to Australia are at greatest risk of developing MVE, due to their lack of immunity and greater chance of becoming infected. Still, the vast majority of infected individuals exhibit no symptoms, and only a very small fraction present with MVE.
Some of you might remember the concerns over West Nile several years ago, when it was first spreading across the U.S. . While many infected individuals exhibited no symptoms, others would suffer from encephalitis and experience severe health problems. I'm not entirely sure what causes the discrepancy in how people react to the virus, but it might be an exciting topic for future reading.
-Alan Le
Mosquito-borne brain-swelling virus on the rise (ABC Australia)
NSW Health Factsheet for MVEV
Sunday, January 22, 2012
Aerial Baiting
Texas has annually taken to the air to fight the ground war on rabies. Over the last 18 years planes were loaded with hundreds and thousands of packets of rabies vaccines that are dipped in fish oil and fish meat. They will deploy 1.8 million packets this year over a larger area of rural south and west Texas.
The goal of this eradication effort is to vaccinate the foxes and coyotes in the rural areas to create a natural buffer zone from rabies that maybe passing into Texas from Mexico and surrounding areas. This program targets only fox and coyote transmitted rabies but is good start to keep enzootic levels down within these animals since they often have contact with livestock and humans. With the success of this program they will move onto skunk rabies.
The vaccination occurs when the animals eat the fish oil covered packets. January is the optimal time for this operation because food is in short supply because of the winter months and the bait becomes very enticing. Texas scientists got the idea for this aerial baiting system for the distribution of rabies vaccines from a program that was occurring in Canada. This method along with laws that mandate pet rabies vaccines keep rabies levels at an all time low.
Through the 18 years of running this program canine associated rabies fell from 122 to 0, and fox strain rabies fell from 244 to 0. Since the air drop began there have been no human cases of rabies in that region. This immunity circle is really doing its job in keeping rabies from spreading in wildlife and ultimately in the human population.
To read more click here
-Victoria Anikst
The goal of this eradication effort is to vaccinate the foxes and coyotes in the rural areas to create a natural buffer zone from rabies that maybe passing into Texas from Mexico and surrounding areas. This program targets only fox and coyote transmitted rabies but is good start to keep enzootic levels down within these animals since they often have contact with livestock and humans. With the success of this program they will move onto skunk rabies.
The vaccination occurs when the animals eat the fish oil covered packets. January is the optimal time for this operation because food is in short supply because of the winter months and the bait becomes very enticing. Texas scientists got the idea for this aerial baiting system for the distribution of rabies vaccines from a program that was occurring in Canada. This method along with laws that mandate pet rabies vaccines keep rabies levels at an all time low.
Through the 18 years of running this program canine associated rabies fell from 122 to 0, and fox strain rabies fell from 244 to 0. Since the air drop began there have been no human cases of rabies in that region. This immunity circle is really doing its job in keeping rabies from spreading in wildlife and ultimately in the human population.
To read more click here
-Victoria Anikst
Polio Cases Triple in Afghanistan
Polio is currently pandemic in three countries- among them, the one posing the greatest world threat is Afghanistan. Even with the political and military unrest, vaccination teams have been allowed to fulfill their work by the government as well as the Taliban. Th Global Polio Eradication Initiative has stated a near eradication, but this year the cases in Afghanistan tripled- from 25 cases in 2010 to 76 in 2011. This three-fold rise is of international concern since the new cases appeared in regions that were previously believed to be polio-free.
The Afghanistan Ministry of Public Health has indicated that the new cases are of a polio strain seen in Pakistan. This strain has been imported by refugees from endemic areas in Pakistan as well as travelers and tourists. Cases in Pakistan also increased from 80 to 192 in 2011. But not all regions with endemic polio have had similar trends- India, on the other hand, saw a year with no new polio cases.
The World Health Organization and Unicef have devoted $32 million dollars to aid in the effort to eradicate polio. This week, WHO is declaring the three-fold rise in Afghanistan a global public health emergency.
-Angela Cesena
Reference:
http://www.nytimes.com/2012/01/18/world/asia/after-years-of-decline-polio-cases-in-afghanistan-rise.html
The Afghanistan Ministry of Public Health has indicated that the new cases are of a polio strain seen in Pakistan. This strain has been imported by refugees from endemic areas in Pakistan as well as travelers and tourists. Cases in Pakistan also increased from 80 to 192 in 2011. But not all regions with endemic polio have had similar trends- India, on the other hand, saw a year with no new polio cases.
The World Health Organization and Unicef have devoted $32 million dollars to aid in the effort to eradicate polio. This week, WHO is declaring the three-fold rise in Afghanistan a global public health emergency.
-Angela Cesena
Reference:
http://www.nytimes.com/2012/01/18/world/asia/after-years-of-decline-polio-cases-in-afghanistan-rise.html
Can HIV Be Eradicated Without Vaccines?
I read an article recently that discussed the potential for eradicating HIV using prophylaxis and anti-retroviral drugs. It's a curious idea since we are taught in class that having a good vaccine is a dominant reason why eradication efforts have worked in the past. Given the nature of HIV spread, the effectiveness (in preventing transmission) and diversity of anti-retroviral drugs, and the lack of a capable, licensed vaccine, suppressing HIV and preventing it's spread may be the best solution; theoretically, it would take a few generations if our only option was to stop spread and wait until the last person with HIV dies, but people are banking on the possibility of reactivating latent HIV reservoirs--a popular area of HIV research--and flushing the virus out of an individual completely, leading to eradication within decades; it won't come cheap though (est. $24 billion a year) and drugs that change the chromatin environment in latent HIV infected cells would need to be developed and approved. One thing that might hamper the effort would be latency in in Hematopoetic Stem Cells!. If eradication through antivirals is successful, it might change the vaccine-centered paradigm. (Original Article)
- NGUyen
Other Cool Stuff:
*In 2006, CDC recommended routine HIV screening for everyone 13-64 years.
*Below: How the Oraquick test works. The way antibodies and enzymes are represented in the picture makes me chuckle.
- NGUyen
Other Cool Stuff:
*In 2006, CDC recommended routine HIV screening for everyone 13-64 years.
*Below: How the Oraquick test works. The way antibodies and enzymes are represented in the picture makes me chuckle.
Ethics of Bird Flu Research
As was discussed in class, the research surrounding H5N1 avian influenza could have benefits in helping understand the microbiology of influenza zoonoses (and thus any possible predictors), but it also carries with it implications of bioterrist weaponization.
On Friday, Ron Fouchier (the premier virologist involved engineering in the virulent strain of H5N1) and a group of other premier flu-ologists issued a letter announcing a suspension of this research, to allow for more discussion by public officials and academics of its possible benefits versus its possible threats. Such a moratorium is extremely rare - the last one having occurred from 1974 to 1976 following safety concerns in recombinant DNA research.
What I found particularly interesting was Fouchier's statement regarding the parallel debate in the Netherlands - where similar research was also taking place. Scientists seem to have taken much more active steps in the Netherlands throughout their research to keep politicians and citizens much more updated and aware of the research. As such, a heated debate as found in the US does not exist in the Netherlands. This strongly indicates that, in the future, any similarly controversial scientific research would really benefit from publicizing itself more than is typically necessary for other research.
Article
Fouchier's letter
- Elena Higuchi
On Friday, Ron Fouchier (the premier virologist involved engineering in the virulent strain of H5N1) and a group of other premier flu-ologists issued a letter announcing a suspension of this research, to allow for more discussion by public officials and academics of its possible benefits versus its possible threats. Such a moratorium is extremely rare - the last one having occurred from 1974 to 1976 following safety concerns in recombinant DNA research.
What I found particularly interesting was Fouchier's statement regarding the parallel debate in the Netherlands - where similar research was also taking place. Scientists seem to have taken much more active steps in the Netherlands throughout their research to keep politicians and citizens much more updated and aware of the research. As such, a heated debate as found in the US does not exist in the Netherlands. This strongly indicates that, in the future, any similarly controversial scientific research would really benefit from publicizing itself more than is typically necessary for other research.
Article
Fouchier's letter
- Elena Higuchi
Bird Flu in China
Two people in China have died from H5N1 in less than a month. This is according to an article run in the New York Times today. China is a country known for agricultural practices that make perfect “breeding grounds” for bird flu and transmission to humans, namely the close proximity and mixing of birds and pigs. Still, these deaths come as a surprise.
The latest victim’s case was worrisome as the patient didn’t report any contact with poultry before falling ill. The concern was that H5N1 might have finally begun to be transmitted human-to-human. However they didn’t rule out other reservoirs that could spread the disease to humans and based on close relatives not becoming ill, it seems that no human-to-human transmission occurred.
However, with bird flu’s high mortality rate it’s no wonder people are so concerned. According to the WHO, bird flu has killed 343 out of 582 people who have reported being infected. This is a worrisome disease and 2 fatal cases in less than a month is a cause for alarm.
The original article can be located for further review at: http://www.nytimes.com/2012/01/23/world/asia/china-reports-2nd-bird-flu-death-in-month.html
--Elena Jordan
The latest victim’s case was worrisome as the patient didn’t report any contact with poultry before falling ill. The concern was that H5N1 might have finally begun to be transmitted human-to-human. However they didn’t rule out other reservoirs that could spread the disease to humans and based on close relatives not becoming ill, it seems that no human-to-human transmission occurred.
However, with bird flu’s high mortality rate it’s no wonder people are so concerned. According to the WHO, bird flu has killed 343 out of 582 people who have reported being infected. This is a worrisome disease and 2 fatal cases in less than a month is a cause for alarm.
The original article can be located for further review at: http://www.nytimes.com/2012/01/23/world/asia/china-reports-2nd-bird-flu-death-in-month.html
--Elena Jordan
Henipaviruses
Since we didn't really get around to Nipah and Hendra...
Hendra virus (a paramyxo) is an Australian BABO zoonotic virus (found in "flying foxes") that most commonly kills horses. Since discovered in 1994, many horses and 4/7 people have died from infection, but human-to-human transmission has not been recorded. Symptoms in horses include respiratory and neurological symptoms. The fatality rate is ~75%. Symptoms in humans can range from mild influenza-like illness to fatal pulmonary, neurologic, or systemic failure.
Most recently, a horse died from Hendra in Australia in early January, marking the 18th outbreak in a year. Some people are calling for the nearby bats to be killed or at least their population thinned, but others argue that this could distress the bats and lead to behavior that infects more horses.
It's interesting to me that we group Hendra and Nipah together in our panic about zoonotic viruses. Yes, they share many characteristics: structure, disease symptoms, spread by bats, and infection of local livestock. However, Nipah has killed many more people, infects a wider range of livestock (commonly pigs, our favorite mixing vessels), and can be transmitted from human to human (nosocomial spread!!). It has hit Malaysia, Singapore, Bangladesh, and India, making it more geographically important than Hendra. Currently, we don't have to worry much about Hendra virus, but perhaps we ought to worry about Nipah...
-Annelise
Hendra virus (a paramyxo) is an Australian BABO zoonotic virus (found in "flying foxes") that most commonly kills horses. Since discovered in 1994, many horses and 4/7 people have died from infection, but human-to-human transmission has not been recorded. Symptoms in horses include respiratory and neurological symptoms. The fatality rate is ~75%. Symptoms in humans can range from mild influenza-like illness to fatal pulmonary, neurologic, or systemic failure.
Most recently, a horse died from Hendra in Australia in early January, marking the 18th outbreak in a year. Some people are calling for the nearby bats to be killed or at least their population thinned, but others argue that this could distress the bats and lead to behavior that infects more horses.
It's interesting to me that we group Hendra and Nipah together in our panic about zoonotic viruses. Yes, they share many characteristics: structure, disease symptoms, spread by bats, and infection of local livestock. However, Nipah has killed many more people, infects a wider range of livestock (commonly pigs, our favorite mixing vessels), and can be transmitted from human to human (nosocomial spread!!). It has hit Malaysia, Singapore, Bangladesh, and India, making it more geographically important than Hendra. Currently, we don't have to worry much about Hendra virus, but perhaps we ought to worry about Nipah...
-Annelise
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