New H7N9 bird flu resists drugs without losing ability to spread

Mutated bird flu virus could cause a worldwide fatal epidemic if it falls into the wrong hands.

A student dons a mask to protect himself against the spread of germs. The H7N9 bird flu virus, which has so far infected at least 139 people and killed 45 across China, Taiwan and Hong Kong, overall does not spread very efficiently, researchers said, though the potential for a pandemic still exists.    KIN CHEUNG/REUTERS

The findings suggest that doctors should use drugs other than Tamiflu to treat H7N9, which has so far infected at least 139 people in China, Taiwan and Hong Kong, researchers said.

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Top US virologist: Prepare now for deadly bird flu mutation

["Female Activist In Protective Suit For Bio-Hazard" on Shutterstock]

By Agence France-Presse
Sunday, April 28, 2013

AFP – There is no evidence that the deadly H7N9 bird flu has yet spread between humans in China but health authorities must be ready for the virus to mutate at any time, a top US virologist has warned.

Anthony Fauci, the head of the National Institute of Allergy and Infectious Diseases (NIAID), said officials in China had studied more than 1,000 close contacts of confirmed cases and not found any evidence of human-to-human transmission.

“That is powerful evidence because if you had a thousand contacts with someone with the flu you would be pretty sure some of them would have been infected,” Fauci said in an interview with AFP.

Nevertheless, Fauci cautioned that authorities needed to be ready for the possibility of the virus mutating and spreading between humans.

“It’s unpredictable as are all the influenza. One of the things we need to be concerned about is this might gain the capability of going human-to-human which up to this point has not happened and is somewhat encouraging news,” Fauci said.

“But we still need to be very prepared for the eventuality of that happening.”

Researchers are already developing a diagnostic test to identify H7N9, along with a vaccine, with clinical trials due in July or August.

“Work is under way on making a diagnostic test to be able to pick it up quickly,” Fauci said.

“We have already started on an early development of a vaccine as we did with H5N1 years ago… Hopefully, we will never have to use it.”

More than 110 people in mainland China have been confirmed to be infected with H7N9, with 23 deaths, since Beijing announced on March 31 that the virus had been found in humans.

Most of the cases have been located in eastern China, although Taiwan has reported one case. Another case has been found in southern China, while Chinese officials confirmed a further outbreak in the central province of Hunan.

Chinese authorities have identified poultry as the source of the virus and have confirmed that patients became sick from contact with infected live fowl.

A visiting team from the World Health Organization, which wrapped up a week-long visit to China on Wednesday, said there had been no human-to-human transmission but warned H7N9 was “one of the most lethal” influenza viruses ever seen.

Fauci praised Beijing for its handling of the current crisis, contrasting it to the response of the outbreak of severe acute respiratory syndrome in 2002-2003, when China stood accused of covering-up the scale of the crisis.

“It was not the case with SARS in 2003 but the transparency has been excellent,” Fauci said. “I am quite satisfied with the Chinese response.”

Fauci likened the current H7N9 strain of bird flu “in some respects” to the H5N1 bird flu strain of several years ago.

“The similarities are that it is fundamentally a chicken or bird flu that jumps from chicken to humans and is quite severe when it infects humans,” he said.

However, Fauci added: “The difference between H7N9 and H5N1, is that H5N1 kills chickens very rapidly so it is easy to identify where the infected flocks of chickens are. H7N9 doesn’t make the chicken sick, so it has been difficult to pinpoint where the infected chickens are.”

There have been 566 confirmed cases of the H5N1 strain of bird flu, which killed 332 people in the world — a mortality rate of 58 percent, compared to 20 percent for the H7N9 bird flu strain.

The H1N1 “swine flu” pandemic o 2009, which appeared in Mexico at the same time of year as the H7N9, eventually infected 60 million people throughout the world and killed more than 12,000.

The 1918 Spanish flu, which has been called one of the deadliest plagues in human history, had a mortality rate of only two percent.



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WHO Says H7N9 is “Most Lethal” Bird Flu Virus

Published on Apr 24, 2013

An international team of experts from the World Health Organization has been in China this week investigating the cases of H7N9 bird flu. They say it is proving to be the most lethal flu virus for humans.

[Keiji Fukuda, WHO Assistant Director-General for Health:]
“There are some other examples of influenza viruses which are very dangerous for humans. You know, I think the H5N1 bird flu virus is one of the famous examples of how dangerous influenza virus can be for people in terms of being lethal. But this is definitely one of the most lethal influenza viruses that we’ve seen so far.”

The WHO says the virus is difficult to track and control due to the lack of any visible signs of illness in the poultry.WHO experts have also said that the new strain is proving easier to contract from birds than the H5N1.

[Nancy Cox, Director, U.S. Disease Control and Prevention Center:]
“So far, no samples from migratory birds and their habitats have been positive for H7N9. In contrast, samples from chickens ducks and pigeons have been positive for H7N9 from the poultry market. Also environmental samples taken from poultry markets have been positive.”

Shandong Province reported its first case of bird flu on Tuesday, bringing the total number of confirmed cases to 108.

Twenty two have died from the virus to date.

So far, there is no evidence of the virus being transmissible between humans. But experts are are still investigating whether the virus could mutate to spread between people.


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UN investigating possible human-to-human transmission of new deadly bird flu in Shanghai

Woman in face mask via Shutterstock

By David Ferguson
Thursday, April 18, 2013

Chinese health officials are reporting that the new H7N9 strain of influenza could be making the leap from animal-to-human infections to human-to-human cases. According to Reuters, the Chinese Center for Disease Control and Prevention is analyzing “family clusters” of people who have fallen ill in hopes of understanding more about the virus.

“We are paying close attention to these cases of family clusters,” Feng Zijian, a spokesperson for the Center, said on Wednesday. “(We) are still analyzing in-depth to see which has the greatest possibility — did it occur first from avian-to-human transmission, and then a human-to-human infection, whether they had a common history of exposure, were exposed to infected objects or whether it was caused by the environment.”

Dr Zeng Guang of the the Center’s chief of epidemiology was quoted in the South China Morning Post as saying that 40 percent of patients who have contracted the virus have not had any contact with poultry or birds that could spread the disease.

“How were they infected? It is still a mystery,” he said.

The current number of confirmed infections stands at 82, 17 of whom have died.

“Further investigations are still under way to figure out whether the family cluster involved human-to-human transmission,” Feng told China Daily. “Human-to-human transmission, in theory, is possible, but is highly sporadic.”

Among the cases that scientists are studying are the deaths of a Shanghai father may have passed the virus to his two sons and another Shanghai man who may have given the disease to his wife.

The World Health Organization, which operates under the aegis of the United Nations, is sending a team of experts to China to study whether the virus has mutated into a human-to-human transmissible form. Currently, however, there is “no evidence of sustained human-to-human transmission.”

Viruses which are only capable of limited human-to-human transmission and can spread between family members through prolonged contact and intimate exposure are considered lower risk than viruses that are capable of effective human transmission, and spread through casual contact like norovirus and the flu.

The H1N1 avian virus that infected people in 2009 and 2010 was of limited human transmissibility, and as a result, caused hundreds of thousand deaths rather than millions. An avian flu that is capable of effective human-to-human transmission could potentially pose a global health emergency.


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