Showing posts with label AVIAN Flu. Show all posts
Showing posts with label AVIAN Flu. Show all posts

Tuesday, June 19, 2012

Dutch H5N1 Flu researchers Eager to Restart their Hybridisation work

After six months of dispute, research in the Netherlands that made a deadly H5N1 flu airborne will be published this week. The scientists behind it now want to get on with their work – but they can't.

In December 2011, a US biosecurity committee advised against publishing the research, fearing it was "dual-use research of concern" (DURC) – done for noble reasons, but dangerous if pathogens escaped or if bioterrorists obtained them. Most committee members changed their minds in April, and approved publication.

But in January, before that turnaround, the world's top flu labs declared a moratorium on any further such research in a bid to calm the situation. "Now, we don't know under what conditions we can lift the moratorium," says Ab Osterhaus of the Erasmus Medical Center in Rotterdam, where the research was done.

In theory they can at any time, because the agreement was voluntary. The problem, says Anthony Fauci, head of the US National Institute of Allergy and Infectious Diseases, is that any similar research done before ground rules for DURC are clarified could run into a similar dispute over publishing.

The US hastily published a new DURC policy in March. It says that if work with any of 15 pathogens increases virulence, transmission, hosts or resistance to defences, researchers must apply a mitigation plan to be agreed by relevant authorities. 

This may include increased containment, changing the experiment, withholding results, classifying the work under secrecy rules – or just not doing it.

A further plan will be published soon, says Fauci. It will flesh out what risks are unacceptable and how to mitigate them, and draw up a committee from US government agencies to apply the rules.

Some researchers welcome the move. "The policy adds another layer of oversight to make sure that all angles have been discussed before and after an experiment with potential dual use," says Adolfo GarcĂ­a-Sastre at the Mount Sinai School of Medicine in New York City.

Others fear trouble. Ron Fouchier, who led the Dutch work on H5N1, says the Dutch authorities are happy with his biocontainment precautions, but a US committee is re-examining them under the new DURC rules. 

He worries that pathogen research could simply leave the US. Fouchier thinks researchers and authorities should discuss safety while planning research – and that it should apply to more than the 15 pathogens.

"We need international guidelines on how to decide who can do what, based on the risks and benefits of the research," says Osterhaus. At the moment, he adds, not even bio-containment labs are standardised. He has asked the European Commission to get involved.

The World Health Organization will publish new guidelines on biosafety in coming weeks, and plans a global meeting on DURC issues next year.

David Heymann, chairman of the UK Health Protection Agency, agrees that global standards are needed.

"Stronger regulations are easy, but they're false security, as they either are not enforced, or affect law-abiding scientists but not rogues," he says. What will work, he adds, is if scientists agree on how to do research safely – and enforce this through peer pressure.

Thursday, October 27, 2011

Veterinary researchers discover first U.S. strains of hepatitis E virus from rabbits | ScienceBlog.com

Researchers in the Virginia-Maryland Regional College of Veterinary Medicine at Virginia Tech have identified the first strains of hepatitis E virus from farmed rabbits in the United States.

It is unknown whether the virus can spread from rabbits to humans.

Caitlin Cossaboom of Salisbury, Md., a second-year student in the combined Doctor of Veterinary Medicine and Ph.D. program in the Department of Biomedical Sciences and Pathobiology, is the first author of a publication entitled “Hepatitis E Virus in Rabbits, Virginia, USA” in the November issue of Emerging Infectious Diseases, published by the U.S. Centers for Disease Control and Prevention.

“Although researchers found hepatitis E virus in rabbits in China in 2009, this is the first time the virus has been identified in rabbits in the United States or anywhere outside of China,” Cossaboom said.

Dr. X.J. Meng, professor of biomedical sciences and pathobiology in the veterinary college, Cossaboom’s graduate advisor, and senior author of the study, identified the first animal strains of hepatitis E virus — swine hepatitis E virus from pigs — in 1997.

Following the landmark study on swine hepatitis E virus by Meng and his colleagues at the National Institutes of Health’s National Institute of Allergy and Infectious Diseases, researchers began to consider hepatitis E virus a zoonotic virus.

“Since 1997, researchers have found hepatitis E virus in pigs essentially in every swine-producing country and shown that the virus from pigs can infect humans,” said Meng.

He added that his lab also identified avian hepatitis E virus from chickens in the United States and that other researchers later discovered strains of the virus in other animal species, including rats, mongoose, deer, and wild boars.

Hepatitis E is an acute hepatic disease caused by infection with an RNA virus that has a fecal-oral transmission route.

The disease is mainly prevalent in developing countries, though sporadic cases have been reported in industrialized countries such as the United States.

The mortality rate associated with hepatitis E virus infection in humans is generally less than 1 percent, but it can reach up to 28 percent in infected pregnant women.

The virus has at least four distinct genotypes. Genotypes 1 and 2 infect only humans and typically occur in developing countries with poor sanitation conditions.

Meanwhile, genotypes 3 and 4 are zoonotic, can spread from animals to humans, and are found in both industrialised and developing countries.

“It is worth noting that the strains of the virus found in rabbits in the U.S. and China closely relate to genotype 3, a genotype that has been shown to transfer from animals to humans,” Meng said.

“The question is, ‘Do the strains of hepatitis E virus in rabbits infect humans?’ We don’t know, but the possibility is there and more research is needed to address this potential concern.”

She added that pigs can serve as “animal reservoirs” for genotypes 3 and 4 hepatitis E virus. In other words, the pigs can carry and shed the virus, and occasionally the virus may transmit to humans.

“However, it is unknown if the virus from rabbits can infect across species or serve as a reservoir,” Cossaboom said.

There are five known types of viral hepatitis: Hepatitis A transmits from person to person from ingesting contaminated food and water. Hepatitis B and C spread by blood-to-blood contact; the hepatitis C virus can also cause chronic infection and, in some cases, liver cancer.

Hepatitis D occurs in individuals who already have hepatitis B. Although all of these viruses, including hepatitis E virus, target the liver, none of them are genetically related.

Sunday, March 14, 2010

H5N1 Avian Flu: Labs Producing Virulent Flu Strains

Engineered hybrids of H5N1 bird and H1N1 human flu strains have proven virulent in mice, raising the danger that a natural recombination would be deadly to humans.

For years, researchers have worried that H5N1 avian influenza would mix with human flu viruses, evolving into a form that keeps its current lethality but is far more contagious.
That hasn’t happened in the wild yet but the latest findings, published Feb. 22 in the Proceedings of the National Academy of Sciences, show how easily it can happen.

“Fortunately, the H5N1 viruses still lack the ability to transmit efficiently among humans.” However, the virus may soon be overcome this obstacle when it mixes with human flu strains. These are the findings of researchers led by University of Wisconsin virologist Yoshihiro Kawaoka. “The next pandemic is inevitable and it will be more devastating than the last.”

Current strains of H5N1 have infected 478 people since 2003, and killed 286 of them. It’s has difficulty transmitting to humans. It requires close contact and exposure to an infected person, bird or animal.
In birds, however, H5N1 is far more contagious, and here the virus has killed tens of millions of fowl. Fortunately, cases have been concentrated in Africa and Eurasia, but as the swine flu pandemic demonstrated, any flu contagious to humans will quickly spread on a global scale. This is mainly thanks to air travel and the free movement of peoples across state boundaries.

Influenza viruses mutate and swap genes easily, with co-infections turning animals into mobile petri dishes. In 2008, hoping to learn more about how H5N1 might evolve, researchers from the Centers for Disease Control and Prevention combined it with a common human flu strain.
The researchers engineered all 254 possible variants of hybridisation between the deadly H5N1 avian flu strain found in Borneo, and a, H1N1 human flu virus from Tokyo. They identified three strains that were both contagious and deadly, in mice.

A flu virus that kills mice won’t necessarily kill humans, but the results are very disturbing. All three killer hybrid strains possessed a protein taken from the human strain. Called PB2, the protein appeared to help the virus survive in the mice’s upper respiratory tract. As of now, bird flu stays in the lower respiratory tract, where it’s less likely to be casually transmitted.

Although the recent H1N1 pandemic has not proved to be as lethal as originally feared, it certainly exposed how unprepared the world is for new influenza strains. At the same time it also exposed the ability of pharmaceutical companies to frighten the WHO, governments and politicians into spending $Millions to stockpile ineffective vaccines.

In May, Hong Kong University virologist Yi Guan, best known for finding the animal origin of SARS, was asked by Science Insider about the possibility of H5N1 and swine flu mixing.

“If that happens, I will retire immediately and lock myself in a sealed laboratory", said Guan. "But, historically the Chinese mainland would be the most likely source of such a virus."
"Unfortunately, in such a situation, the imposed cover-up by local authorities would mean that the virus will have spread with a high rate of cross-infection and will have escaped globally, even before we are alerted to it's existance. We will not be alerted until it has spread to the Western world and many people have become infected and died."

Monday, March 1, 2010

H5N1: AVIAN Flu death in Vietnam

A 38-year-old woman has become the first victim of bird flu in Vietnam in 2010, bringing the country's toll from avian influenza to 58, the health ministry said Friday.

The woman died Tuesday in the southern province of Tien Giang after two days of unsuccessful hospital treatment, said the ministry in an online statement.

The victim had killed and cooked sick waterfowl, the statement added.

Vietnam's last death from the H5N1 virus was in December.

At present, outbreaks of bird flu among poultry have been reported in five provinces.

Vietnam ranks second after Indonesia for the highest bird flu death toll, according to the World Health Organization.

The H5N1 virus typically spreads from birds to humans via direct contact, but experts fear it could mutate into a form easily transmissible between humans, with the potential to kill millions in a pandemic.