Hey all, although this may not be a biologically oriented article, I think it's important for us to keep tabs on public perception of viruses in general, in this case perception of the sources of disease. Particularly in the case of HIV, perception about the origins of a disease can have a great effect upon efforts in prevention and public health approaches to fight the disease. It would be interesting to attempt to incorporate stigma, spread by people such as the bishop in this article, into some sort of quantifiable variable in epidemiological calculations about the spread of disease, like R-naught values that determine if a disease is likely to become epidemic. At the very least, this article can help us realize the importance of having the right information, and maybe demonstrate the importance of putting the things we learn in this class into some sort of applicable efforts. Don't kill your computer screen if the article's too frustrating!
http://www.msnbc.msn.com/id/20999747/
Jon Dyal
Sunday, September 30, 2007
New Mexico's rodent problem
Two days ago, Friday, a 58-yr-old woman living in the East Mountain county of New Mexico was diagnosed with bubonic plague. The source is as of yet unidentified, but the investigators are guessing it's the typical suspect for bubonic plague: being around rodents and the fleas that live on rodents. The poor woman is currently in the hospital, recovering rather nicely, and doing as well as can be expected after she's grew several bulbous nubbins where her lymph nodes should be.
Surprisingly, this is the fifth confirmed case of bubonic plague New Mexico has seen so far in 2007. According to the CDC website, there are only about 10-15 confirmed cases in the U.S. every year. This year doesn't seem to be an anomaly for NM either; its track record indicates that bubonic plague has a greater incidence in NM than in other parts of the U.S. In 2006, there were 8 reported cases and 4 cases in 2005.
New Mexico had a rodent problem back in 1997-'98 with its hantavirus pulmonary syndrome outbreak caused by the "Sin Nombre virus", whose vectors were mice and the lovely gifts they'd leave all over people's floors.
As a side note, I couldn't help but think of the Disney movie, Fifel Goes West-- did anyone watch that? And Rescuers Down Under, but that was more Australia-based. Then there's mickey and minnie. Come to think of it, Disney really loves its rodents... We're sending our kids the wrong message that all rodents are fuzzy, huggable, lovable creatues. I guess long as none of them have plague-infested fleas or are carrying hantavirus, they're safe. :)
-Jessie
link to promed source Here
Surprisingly, this is the fifth confirmed case of bubonic plague New Mexico has seen so far in 2007. According to the CDC website, there are only about 10-15 confirmed cases in the U.S. every year. This year doesn't seem to be an anomaly for NM either; its track record indicates that bubonic plague has a greater incidence in NM than in other parts of the U.S. In 2006, there were 8 reported cases and 4 cases in 2005.
New Mexico had a rodent problem back in 1997-'98 with its hantavirus pulmonary syndrome outbreak caused by the "Sin Nombre virus", whose vectors were mice and the lovely gifts they'd leave all over people's floors.
As a side note, I couldn't help but think of the Disney movie, Fifel Goes West-- did anyone watch that? And Rescuers Down Under, but that was more Australia-based. Then there's mickey and minnie. Come to think of it, Disney really loves its rodents... We're sending our kids the wrong message that all rodents are fuzzy, huggable, lovable creatues. I guess long as none of them have plague-infested fleas or are carrying hantavirus, they're safe. :)
-Jessie
link to promed source Here
Saturday, September 29, 2007
Trying to Control Ebola Outbreak in the Congo
I mentioned the Ebola outbreak in the Democratic Republic of the Congo in class and I found this updated article on the WHO website. The Center for Disease Control and the National Public Health Agency of Canada have set up labs in affected areas, and teams are currently focusing on analyzing the outbreak. So far, there have been 17 cases. Luckily, they are able to use radio to communicate with the citizens to explain important precautions as well as try to assuage the fear. To control any sort of outbreak, especially of a virus this contagious and dangerous, rapid and effective communication is essential. I hope they are able to prevent further cases!
http://www.who.int/csr/don/2007_09_27/en/index.html
Jasmeen
http://www.who.int/csr/don/2007_09_27/en/index.html
Jasmeen
Had to post this
I had to post again when I came across this article; too funny. Barry Bond's famous 756th ball is to be branded with an asterisk: http://www.nydailynews.com/sports/baseball/2007/09/27/2007-09-27_poll_results_say_barry_bonds_ball_will_h.html?ref=rss
As funny as that is (which is hilarious), the guy paid around $750,000 to do that. That money could have been put to (in no particular order of importance): vaccinations, infectious disease research, or buying me a new car. Sad.
-Thomas
As funny as that is (which is hilarious), the guy paid around $750,000 to do that. That money could have been put to (in no particular order of importance): vaccinations, infectious disease research, or buying me a new car. Sad.
-Thomas
Rwanda to urge male circumcision in AIDS fight
So, apparently there's an HIV/AIDS epidemic in parts of Africa. The Rwandan government is trying a new tactic to fight it: encouraging male circumcision. Studies show that this reduces the risk of transmission by about 60%! But only 1 in every five males are circumcized. The details about how exactly they're going to implement the plan are still a bit sketchy, but they include training health workers and producing a nationwide public campaign for the procedure.
The link to the story is here:
http://news.yahoo.com/s/nm/20070928/hl_nm/aids_rwanda_dc;_ylt=AiyCg4hEh1tw9reeOiIX3bjVJRIF
The link to the story is here:
http://news.yahoo.com/s/nm/20070928/hl_nm/aids_rwanda_dc;_ylt=AiyCg4hEh1tw9reeOiIX3bjVJRIF
Cold medicine harmful to young kids! FDA takes action
Drug labels advising caretakers to "consult a physician" before giving cold and cough medicine to children under 2 may not be in the best interest of the kids.
The FDA has scheduled a meeting for next month to address reports from Baltimore city officials and the American Academy of Pediatrics that over-the-counter cold medicines are ineffective and dangerous when given to young kids. Between 1969 and 2006, the Consumer Healthcare Products Association recorded 123 deaths related to decongestant and antihistamine use. The CDC reported that in 2 years, over 1,500 young kids were admitted to emergency rooms after taking cold or cough medicine.
Instead of advising caretakers to "consult a physician" before giving cold and cough medicine to kids under 2, the FDA's preliminary recommendation is that no decongestant should be given to kids under 2, and no antihistamines to kids under 6. The Consumer Healthcare Products Association, which represents the drug companies, adds that antihistamines also shouldn't be used to sedate kids.
The FDA meeting is scheduled for October 18-19. Stay tuned for possible upcoming label changes.
Link to article in the SF Chronicle: http://sfgate.com/cgi-bin/article.cgi?f=/n/a/2007/09/28/national/w102034D62.DTL&hw=cold+cough&sn=001&sc=1000
-Becky
The FDA has scheduled a meeting for next month to address reports from Baltimore city officials and the American Academy of Pediatrics that over-the-counter cold medicines are ineffective and dangerous when given to young kids. Between 1969 and 2006, the Consumer Healthcare Products Association recorded 123 deaths related to decongestant and antihistamine use. The CDC reported that in 2 years, over 1,500 young kids were admitted to emergency rooms after taking cold or cough medicine.
Instead of advising caretakers to "consult a physician" before giving cold and cough medicine to kids under 2, the FDA's preliminary recommendation is that no decongestant should be given to kids under 2, and no antihistamines to kids under 6. The Consumer Healthcare Products Association, which represents the drug companies, adds that antihistamines also shouldn't be used to sedate kids.
The FDA meeting is scheduled for October 18-19. Stay tuned for possible upcoming label changes.
Link to article in the SF Chronicle: http://sfgate.com/cgi-bin/article.cgi?f=/n/a/2007/09/28/national/w102034D62.DTL&hw=cold+cough&sn=001&sc=1000
-Becky
A New Fight Against the Bite!
Outbreaks of West Nile virus in the U.S. are becoming an increasing health concern. At least, every time my mother sees a dead crow (a reservoir for the virus)--or any other dead bird , for that matter--she sends us all packing for the indoors. This brief article brings hope to her, as well as all mothers everywhere. Researchers at Acambis have modified the yellow fever vaccine with West Nile surface protein genes in the hopes of creating an effective immunization against this "new" concern.
This article shares some insight into the methodology that goes developing vaccines. The report also got me thinking about some additional issues related to West Nile: If modified yellow fever can act as a vaccine against West Nile, does the yellow fever vaccine alone confer any resistance against West Nile? What does the fact that, now that West Nile has hit home in the US, researchers are mounting a fight against the disease? After all, West Nile has been around since the 1930s in other regions of the world, but we've only developed an equine West Nile vaccine thus far.
Check out the link:
http://www.americanchronicle.com/articles/viewArticle.asp?articleID=38855
And for a little more background on West Nile and how to protect yourself (after all, knowledge is power):
http://www.cnn.com/HEALTH/library/DS/00438.html
This article shares some insight into the methodology that goes developing vaccines. The report also got me thinking about some additional issues related to West Nile: If modified yellow fever can act as a vaccine against West Nile, does the yellow fever vaccine alone confer any resistance against West Nile? What does the fact that, now that West Nile has hit home in the US, researchers are mounting a fight against the disease? After all, West Nile has been around since the 1930s in other regions of the world, but we've only developed an equine West Nile vaccine thus far.
Check out the link:
http://www.americanchronicle.com/articles/viewArticle.asp?articleID=38855
And for a little more background on West Nile and how to protect yourself (after all, knowledge is power):
http://www.cnn.com/HEALTH/library/DS/00438.html
Friday, September 28, 2007
Smallpox: older than previously thought?
Researchers at the CDC and Lawrence Livermore National Laboratory published results this month indicating that smallpox is older than previous estimations.
Collaborators at the labs sequenced genomes of 47 geographic isolates of smallpox gathered between 1946 and 1977. Comparison of the rates of random mutations (single nucleotide polymorphisms, or SNPs) allowed the scientists to calibrate a "molecular clock" which suggests the strain diverged either 16,000 or 68,000 years ago. The large disparity in the estimated dates depends on whether data from East Asia or Africa is used to calibrate the molecular clock.
Check out the news release describing the results here.
I'm not very sure how accurate these molecular clocks are... it's interesting to think that smallpox spread westward from East Asia, since some of the oldest descriptions of smallpox-like disease come from ancient China.
Lauren Smith
Collaborators at the labs sequenced genomes of 47 geographic isolates of smallpox gathered between 1946 and 1977. Comparison of the rates of random mutations (single nucleotide polymorphisms, or SNPs) allowed the scientists to calibrate a "molecular clock" which suggests the strain diverged either 16,000 or 68,000 years ago. The large disparity in the estimated dates depends on whether data from East Asia or Africa is used to calibrate the molecular clock.
Check out the news release describing the results here.
I'm not very sure how accurate these molecular clocks are... it's interesting to think that smallpox spread westward from East Asia, since some of the oldest descriptions of smallpox-like disease come from ancient China.
Lauren Smith
Outbreak of the Coronavirus Causing SARS On Flight in Hong Kong
http://www.cnn.com/2003/HEALTH/03/25/mystery.flu/index.html
9 passengers aboard a Hong Kong flight to Beijing caught the virus, leaving them with SARS. They are believed to have contracted the virus from a man on the flight who caught it from a sick relative he had been visiting. Honk Kong is now concerned about the transmission of this virus on flights, where quarantines have not been as strong (for comparison, the article mentions the dispersal of face masks at train stations in Hong Kong to prevent transmission, but as far as I can tell, no similar procedure exists for air travel).
The article also mentions that on Monday, U.S. scientists had linked SARS to a new form of coronavirus, and that scientists in Hong Kong have isolated the virus and have developed a new test to identify it.
Nick
9 passengers aboard a Hong Kong flight to Beijing caught the virus, leaving them with SARS. They are believed to have contracted the virus from a man on the flight who caught it from a sick relative he had been visiting. Honk Kong is now concerned about the transmission of this virus on flights, where quarantines have not been as strong (for comparison, the article mentions the dispersal of face masks at train stations in Hong Kong to prevent transmission, but as far as I can tell, no similar procedure exists for air travel).
The article also mentions that on Monday, U.S. scientists had linked SARS to a new form of coronavirus, and that scientists in Hong Kong have isolated the virus and have developed a new test to identify it.
Nick
Hand, Foot, and Mouth Disease in China
Hey guys! So I signed up for ProMed mail yesterday and I've already gotten 23 notices!!! Apparently viruses are taking over the world. Anyways, I found this really interesting article on ProMed about Hand, Foot, and Mouth disease in Vietnam. Since the start of September, over 170 infants have been diagnosed weekly with HFMD. Children are exposed to the viruses Coxsackie and Entero 71 viruses, which cause the disease, through toys and food. I've posted the link below but I wanted to point out an interesting aspect of this article. These outbreaks have been occurring earlier in the year than in previous years, when the disease had usually peaked in March or November. I haven't been able to come up with a reason why. Thoughts??
http://www.promedmail.org/pls/promed/f?p=2400:1001:9280585519259184379::NO::F2400_P1001_BACK_PAGE,F2400_P1001_PUB_MAIL_ID:1010,39475
-Ani
http://www.promedmail.org/pls/promed/f?p=2400:1001:9280585519259184379::NO::F2400_P1001_BACK_PAGE,F2400_P1001_PUB_MAIL_ID:1010,39475
-Ani
Transplacental Transmission of Avian Influenza H5N1
Good morning all!
On Thursday, September 27 researchers from Columbia and Peking Universities reported that the H5N1 avian flu virus can be transmitted through a pregnant woman's placenta and infect the fetus. Researchers found viral genetic material in the four-month old fetus of a 24 year old pregnant woman killed by H5N1 in China. Researchers had previously believed that human influzenza could not pass through the placenta and affect unborn babies.
Samples taken from the pregnant woman and a 35 year old man, another victim of H5N1 in China, revealed viral genetic material not only in the lungs (as expected), but also in the GI tract, brain, liver, and blood cells. The disproportional amount of damage found in the organs compared to the number of cells that were infected supports the theory of a "cytokine storm", where the immune system overreacts to the virus and sends out a swarm of signaling chemicals that end up overwhelming and killing the patient.
H5N1 typically infects birds, but out of the 328 people infected since 2003, 200 have died.
You can find the full article here:
Source: Reuters Foundation AlertNet [edited]
Julia Liebner
On Thursday, September 27 researchers from Columbia and Peking Universities reported that the H5N1 avian flu virus can be transmitted through a pregnant woman's placenta and infect the fetus. Researchers found viral genetic material in the four-month old fetus of a 24 year old pregnant woman killed by H5N1 in China. Researchers had previously believed that human influzenza could not pass through the placenta and affect unborn babies.
Samples taken from the pregnant woman and a 35 year old man, another victim of H5N1 in China, revealed viral genetic material not only in the lungs (as expected), but also in the GI tract, brain, liver, and blood cells. The disproportional amount of damage found in the organs compared to the number of cells that were infected supports the theory of a "cytokine storm", where the immune system overreacts to the virus and sends out a swarm of signaling chemicals that end up overwhelming and killing the patient.
H5N1 typically infects birds, but out of the 328 people infected since 2003, 200 have died.
You can find the full article here:
Source: Reuters Foundation AlertNet [edited]
Julia Liebner
Preparedness for Highly Pathogenic Avian Influenza in Africa
Here's the URL for an article to be published in the 2007 October edition of Emerging Infectious Diseases. I found the article to be interesting, as it discusses the substantial logistical and financial issues involved with securing Africa against the possibility of avian influenza attack. Many African nations don't have the funding nor logistical capacity to combat less virulent infectious agents; if charged with avian flu without resources and a plan, the outcome could be devastating.
http://www.cdc.gov/eid/content/13/10/pdfs/07-0400.pdf
It's not thaaat long.
Elizabeth
http://www.cdc.gov/eid/content/13/10/pdfs/07-0400.pdf
It's not thaaat long.
Elizabeth
Thursday, September 27, 2007
Assessing the Mortality Benefits of Influenza Vaccine in the Elderly
I thought this was interesting because today in another one of my classes we discussed that the best way to prevent mortality from influenza in the elderly population was to vaccinate school aged children. The article below is just a summary of the actual article, but does mention that the authors suggested vaccinating "more people in all age groups to indirectly better protect the elderly." The title of the article is given at the bottom - I would have posted it, but I couldn't access it! Enjoy...
-Alaina
Infectious Diseases (NIAID)
http://www.niaid.nih.gov
FOR IMMEDIATE RELEASE
Monday, Sept. 24, 2007
Media Contact: NIAID News Office
(301) 402-1663
niaidnews@niaid.nih.gov
NIAID MEDIA AVAILABILITY
NIH Scientists Describe Ways to Accurately Assess Mortality Benefits of Influenza Vaccine in the Elderly
WHAT:
Each year, seasonal flu kills approximately 36,000 people in the United States, most over age 70.Yet little is known about the benefit of influenza vaccine in older seniors. Randomized, placebo-controlled clinical trials involving seniors have not been large enough to reveal how well the vaccine can prevent death in this age group.
In an article in the October issue of The Lancet Infectious Diseases, now available online, researchers from the National Institutes of Health (NIH) describe how sources of bias in other, non-randomized studies have inadvertently resulted in an exaggeration of the flu vaccine’s value in preventing flu deaths in the elderly. The authors point to the need for better flu vaccines for seniors, and other strategies to reduce severe influenza outcomes among this age group.
The authors emphasize that even a less-than-ideal influenza vaccine is better than none at all, and that this age group should continue to get a seasonal flu shot. Better vaccines are needed, however, and NIAID supports research to develop new and improved vaccines.
In the meantime, the researchers suggest intensive study of several approaches to reduce influenza-related deaths among the elderly.
* Vaccinate more people in all age groups to indirectly better protect the elderly
* Identify and vaccinate the frail elderly who are at greatest risk of death from flu
* Use antiviral drugs more aggressively to treat and prevent flu in seniors and their contacts
The researchers also outline new epidemiological methods that may aid in establishing a more accurate picture of the impact on mortality of flu vaccination in the elderly.
The paper’s lead author is Lone Simonsen, Ph.D., formerly of the National Institute of Allergy and Infectious Diseases (NIAID), part of the NIH. Other authors include Mark A. Miller, M.D., of NIH’s Fogarty International Center, and Lisa A. Jackson, M.D., of Group Health Center for Health Studies, Seattle.
ARTICLE:
“Mortality benefits of influenza vaccination in elderly people: an ongoing controversy,” by L. Simonsen et al. The Lancet Infectious Diseases 7: 658–66 (2007).
SPOKESPERSONS:
Lone Simonsen, Ph.D., Visiting Professor, George Washington University, Washington, D.C.
Anthony S. Fauci, M.D., Director, NIAID, NIH
Mark Miller, M.D., Division Director, Fogarty International Center, NIH
CONTACT: To schedule interviews, contact the NIAID News and Public Information Branch, (301) 402-1663, niaidnews@niaid.nih.gov.
-Alaina
Infectious Diseases (NIAID)
http://www.niaid.nih.gov
FOR IMMEDIATE RELEASE
Monday, Sept. 24, 2007
Media Contact: NIAID News Office
(301) 402-1663
niaidnews@niaid.nih.gov
NIAID MEDIA AVAILABILITY
NIH Scientists Describe Ways to Accurately Assess Mortality Benefits of Influenza Vaccine in the Elderly
WHAT:
Each year, seasonal flu kills approximately 36,000 people in the United States, most over age 70.Yet little is known about the benefit of influenza vaccine in older seniors. Randomized, placebo-controlled clinical trials involving seniors have not been large enough to reveal how well the vaccine can prevent death in this age group.
In an article in the October issue of The Lancet Infectious Diseases, now available online, researchers from the National Institutes of Health (NIH) describe how sources of bias in other, non-randomized studies have inadvertently resulted in an exaggeration of the flu vaccine’s value in preventing flu deaths in the elderly. The authors point to the need for better flu vaccines for seniors, and other strategies to reduce severe influenza outcomes among this age group.
The authors emphasize that even a less-than-ideal influenza vaccine is better than none at all, and that this age group should continue to get a seasonal flu shot. Better vaccines are needed, however, and NIAID supports research to develop new and improved vaccines.
In the meantime, the researchers suggest intensive study of several approaches to reduce influenza-related deaths among the elderly.
* Vaccinate more people in all age groups to indirectly better protect the elderly
* Identify and vaccinate the frail elderly who are at greatest risk of death from flu
* Use antiviral drugs more aggressively to treat and prevent flu in seniors and their contacts
The researchers also outline new epidemiological methods that may aid in establishing a more accurate picture of the impact on mortality of flu vaccination in the elderly.
The paper’s lead author is Lone Simonsen, Ph.D., formerly of the National Institute of Allergy and Infectious Diseases (NIAID), part of the NIH. Other authors include Mark A. Miller, M.D., of NIH’s Fogarty International Center, and Lisa A. Jackson, M.D., of Group Health Center for Health Studies, Seattle.
ARTICLE:
“Mortality benefits of influenza vaccination in elderly people: an ongoing controversy,” by L. Simonsen et al. The Lancet Infectious Diseases 7: 658–66 (2007).
SPOKESPERSONS:
Lone Simonsen, Ph.D., Visiting Professor, George Washington University, Washington, D.C.
Anthony S. Fauci, M.D., Director, NIAID, NIH
Mark Miller, M.D., Division Director, Fogarty International Center, NIH
CONTACT: To schedule interviews, contact the NIAID News and Public Information Branch, (301) 402-1663, niaidnews@niaid.nih.gov.
Vaccinating Birds?
So I don't know if this counts, because it's primarily about birds, however, since the vaccine would be created with intentions of decreasing the spread of this virus from animals to humans, I thought it was relevant... Wait can someone who knows more about this than I do tell me how realistic it is to even do this? Has it been done before? And isn't there still a really high chance that the flu will just mutate?
-Raquel
Russia: envisaged wild bird vaccine
Date: Tue 25 Sep 2007
Source: RIA Novosti [edited]
http://en.rian.ru:80/russia/20070925/80887629.html
Russia could develop a bird flu vaccine targeted at wild birds within
2 years, creating a revolution in the flight against the disease, the
chief vet at Russia's food safety watchdog said Tuesday [25 Sep 2007].
"It will, speaking mildly, be a revolution, because no one has ever
tried to control the spread of the flu virus among wild birds. And
this is the source of all the trouble," Nikolai Vlasov said.
Bird flu has never really disappeared from Russia since 2005, Vlasov
told journalists, adding that, out of 100 birds that are culled,
around 2-80 will actually have been infected depending on the location.
According to watchdog estimates, by the end of the year [2007], the
numbers of birds which will die from bird flu outbreaks in Russia
will be 4 times lower than last year's [2006] figure.
-Raquel
Russia: envisaged wild bird vaccine
Date: Tue 25 Sep 2007
Source: RIA Novosti [edited]
http://en.rian.ru:80/russia/20070925/80887629.html
Russia could develop a bird flu vaccine targeted at wild birds within
2 years, creating a revolution in the flight against the disease, the
chief vet at Russia's food safety watchdog said Tuesday [25 Sep 2007].
"It will, speaking mildly, be a revolution, because no one has ever
tried to control the spread of the flu virus among wild birds. And
this is the source of all the trouble," Nikolai Vlasov said.
Bird flu has never really disappeared from Russia since 2005, Vlasov
told journalists, adding that, out of 100 birds that are culled,
around 2-80 will actually have been infected depending on the location.
According to watchdog estimates, by the end of the year [2007], the
numbers of birds which will die from bird flu outbreaks in Russia
will be 4 times lower than last year's [2006] figure.
Vaccine-Related Polio Outbreak in Nigeria Raises Concerns
I guess I'll be the first one to post...
Julie Boiko
SCIENCE
28 September 2007
News of the Week
Source: http://www.sciencemag.org/cgi/content/full/317/5846/1842
INFECTIOUS DISEASE: Vaccine-Related Polio Outbreak in Nigeria Raises Concerns
Leslie Roberts
Northern Nigeria has been hit by one of the largest known outbreaks of poliomyelitis caused by the live polio vaccine itself. The ongoing outbreak could be a serious setback for the global polio eradication campaign: It is occurring in a region where rumors about vaccine safety derailed vaccination efforts several years ago.
Experts with the Global Polio Eradication Initiative emphasize that the widely used trivalent oral polio vaccine (OPV) is safe. But the low immunization rates in northern Nigeria have created the conditions for the attenuated vaccine virus to regain its virulence and trigger an outbreak.
Detected in September 2006, the outbreak of vaccine-derived poliovirus (VDPV) type 2 was immediately reported to the World Health Organization and Nigerian health officials. But the information is just now being released publicly--in the 28 September Morbidity and Mortality Weekly Report and WHO's Weekly Epidemiological Record--a delay that has caused some consternation in the polio community. Officials say they were worried that the news, if misconstrued, could again disrupt polio vaccination efforts in Nigeria.
"There were legitimate concerns that anti-polio vaccination rumors would be rekindled by an incomplete explanation of the cause of the VDPV outbreak," says Olen Kew, who has led efforts to analyze the outbreak from the U.S. Centers for Disease Control and Prevention in Atlanta, Georgia.
Several polio experts told Science that although they understand how sensitive the situation is, they disagree with the decision to keep quiet. "I am troubled that the information hasn't come out, absolutely," says Donald A. Henderson of the University of Pittsburgh Center for Biosecurity in Baltimore, Maryland. Henderson says details of each outbreak are essential if scientists are to understand just how risky these vaccine-derived strains are.
So far, there are 69 confirmed cases of paralysis, and more suspected, caused by VDPV in nine northern Nigeria states, says Kew. The case count seems certain to rise. About half the cases have occurred around Kano, a largely Muslim state where anti-Western sentiment and rumors that the vaccine caused sterility or AIDS led several states to halt polio vaccination in 2003. After repeated demonstrations of the vaccine's safety and considerable behind-the-scenes diplomacy, vaccinations resumed about a year later, but the damage had already been done.
By the end of 2004, the number of polio cases in Nigeria had doubled to about 800, and in 2006 it soared to more than 1100. Wild virus from Nigeria reinfected some 20 other countries, leading to a spike in global cases. It was a huge setback to the Global Polio Eradication Initiative, which estimates that the world spent an additional $500 million to contain the damage. Only recently have global cases dropped back to near preboycott levels.
Although Nigeria has since made considerable progress, wild poliovirus, both type 1 and type 3, is still circulating in the north, and vaccine coverage there remains low. In 2006, between 6% and 30% of children in the north had never received a single dose of OPV.
Those are exactly the conditions that render an area susceptible to outbreaks of vaccinederived virus. Since the 1960s, scientists have known that attenuated viruses can in rare instances mutate and regain virulence, but it was only in 2000, with an outbreak in Hispaniola, that they realized VDPVs could spread disease from person to person.
The current outbreak came to light when a technician at the CDC polio lab noticed a preponderance of type 2 virus in the isolates sent in from northern Nigeria. That instantly raised suspicion, Kew says, because wild type 2 poliovirus has been eradicated globally. That meant the only possible source was the trivalent vaccine, which had been used in Nigeria in preboycott campaigns. Since Nigeria resumed vaccinations in 2004, says Kew, it had "quite properly" been using the more effective monovalent vaccines against wild types 1 and 3 in its campaigns. Genetic analysis quickly confirmed the source; it also suggests that several VDPVs emerged independently in 2005 and 2006, multiple times.
In earlier outbreaks, circulating VDPVs have been relatively easy to stamp out, but this one has persisted despite four campaigns with trivalent OPV in the past year. "We suspect it is simply because the coverage was not adequate; we don't believe there is anything exceptional about this virus," says Kew. As evidence, he notes that two VDPV strains jumped from Nigeria to Niger, where routine vaccination is almost 90%. Both "barely made it 5 kilometers before they dead-ended," he says.
Polio expert Oyewale Tomori, vice chancellor of Redeemer's University near Lagos and chair of Nigeria's expert advisory committee for polio eradication, says he has been urging officials to go public. He worries that secrecy might fuel suspicions about vaccine safety instead of reinforcing the need to intensify immunizations in Nigeria.
Julie Boiko
SCIENCE
28 September 2007
News of the Week
Source: http://www.sciencemag.org/cgi/content/full/317/5846/1842
INFECTIOUS DISEASE: Vaccine-Related Polio Outbreak in Nigeria Raises Concerns
Leslie Roberts
Northern Nigeria has been hit by one of the largest known outbreaks of poliomyelitis caused by the live polio vaccine itself. The ongoing outbreak could be a serious setback for the global polio eradication campaign: It is occurring in a region where rumors about vaccine safety derailed vaccination efforts several years ago.
Experts with the Global Polio Eradication Initiative emphasize that the widely used trivalent oral polio vaccine (OPV) is safe. But the low immunization rates in northern Nigeria have created the conditions for the attenuated vaccine virus to regain its virulence and trigger an outbreak.
Detected in September 2006, the outbreak of vaccine-derived poliovirus (VDPV) type 2 was immediately reported to the World Health Organization and Nigerian health officials. But the information is just now being released publicly--in the 28 September Morbidity and Mortality Weekly Report and WHO's Weekly Epidemiological Record--a delay that has caused some consternation in the polio community. Officials say they were worried that the news, if misconstrued, could again disrupt polio vaccination efforts in Nigeria.
"There were legitimate concerns that anti-polio vaccination rumors would be rekindled by an incomplete explanation of the cause of the VDPV outbreak," says Olen Kew, who has led efforts to analyze the outbreak from the U.S. Centers for Disease Control and Prevention in Atlanta, Georgia.
Several polio experts told Science that although they understand how sensitive the situation is, they disagree with the decision to keep quiet. "I am troubled that the information hasn't come out, absolutely," says Donald A. Henderson of the University of Pittsburgh Center for Biosecurity in Baltimore, Maryland. Henderson says details of each outbreak are essential if scientists are to understand just how risky these vaccine-derived strains are.
So far, there are 69 confirmed cases of paralysis, and more suspected, caused by VDPV in nine northern Nigeria states, says Kew. The case count seems certain to rise. About half the cases have occurred around Kano, a largely Muslim state where anti-Western sentiment and rumors that the vaccine caused sterility or AIDS led several states to halt polio vaccination in 2003. After repeated demonstrations of the vaccine's safety and considerable behind-the-scenes diplomacy, vaccinations resumed about a year later, but the damage had already been done.
By the end of 2004, the number of polio cases in Nigeria had doubled to about 800, and in 2006 it soared to more than 1100. Wild virus from Nigeria reinfected some 20 other countries, leading to a spike in global cases. It was a huge setback to the Global Polio Eradication Initiative, which estimates that the world spent an additional $500 million to contain the damage. Only recently have global cases dropped back to near preboycott levels.
Although Nigeria has since made considerable progress, wild poliovirus, both type 1 and type 3, is still circulating in the north, and vaccine coverage there remains low. In 2006, between 6% and 30% of children in the north had never received a single dose of OPV.
Those are exactly the conditions that render an area susceptible to outbreaks of vaccinederived virus. Since the 1960s, scientists have known that attenuated viruses can in rare instances mutate and regain virulence, but it was only in 2000, with an outbreak in Hispaniola, that they realized VDPVs could spread disease from person to person.
The current outbreak came to light when a technician at the CDC polio lab noticed a preponderance of type 2 virus in the isolates sent in from northern Nigeria. That instantly raised suspicion, Kew says, because wild type 2 poliovirus has been eradicated globally. That meant the only possible source was the trivalent vaccine, which had been used in Nigeria in preboycott campaigns. Since Nigeria resumed vaccinations in 2004, says Kew, it had "quite properly" been using the more effective monovalent vaccines against wild types 1 and 3 in its campaigns. Genetic analysis quickly confirmed the source; it also suggests that several VDPVs emerged independently in 2005 and 2006, multiple times.
In earlier outbreaks, circulating VDPVs have been relatively easy to stamp out, but this one has persisted despite four campaigns with trivalent OPV in the past year. "We suspect it is simply because the coverage was not adequate; we don't believe there is anything exceptional about this virus," says Kew. As evidence, he notes that two VDPV strains jumped from Nigeria to Niger, where routine vaccination is almost 90%. Both "barely made it 5 kilometers before they dead-ended," he says.
Polio expert Oyewale Tomori, vice chancellor of Redeemer's University near Lagos and chair of Nigeria's expert advisory committee for polio eradication, says he has been urging officials to go public. He worries that secrecy might fuel suspicions about vaccine safety instead of reinforcing the need to intensify immunizations in Nigeria.
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