Avian flu mutant flu virus dangerous?

Avian Flu: Mutated flu virus can be a danger to humans

06/22/2012

The H5N1 virus, known as bird flu, is particularly dangerous to birds. However, five mutations of the virus are already sufficient to pass from human to human via droplet infection. Then a handshake is enough to get infected with the virus.

After just five mutations, the bird flu virus becomes threatening to humans
Until now, birds were primarily affected by the H5N1 virus. According to a study in the journal „Science“ However, it may only be a matter of time before bird flu spreads among humans and becomes a pandemic. An international research team led by Sander Herfst of the Erasmus Medical Center in Rotterdam, the Netherlands, found that five mutations in the genome of the virus are already sufficient to spread from human to human as a droplet infection. According to the study, the mutations could take place within a single virus type. There are no mixtures of different subtypes of the pathogen required, the researchers. In their experiment the virus could be combated medically. Even the vaccines currently approved in Europe have been used successfully.

Experts are worried that they believe a global pandemic is unlikely. In their investigations, the researchers therefore addressed the question of which mutations take place in the genome of the pathogen in order to enable a droplet infection that would promote a rapid spread of bird flu from person to person. First, the genetic makeup of the virus has been modified at three specific sites to ensure that it can spread more easily among mammals. In the next step, the researchers infected ferrets with the pathogen, as they can be infected with human viruses and show a similar course of the disease. By smears from the nose of the infected animals more ferrets were infected. The researchers repeated this process several times to simulate a natural infection situation. When investigating the viruses after some time had passed, the researchers found that in addition to the three intentionally mutated genetic material positions additional changes had occurred, which led to the virus being able to spread better.

Droplet infection in bird flu possible
To test whether the mutant virus might also be transmitted by air, the researchers placed cages with healthy ferrets beside those with the infected animals. The shocking result: most of the healthy animals also fell ill. Already five mutations were enough to allow a droplet infection. It is particularly important that the five mutations could arise within a host and a single virus type. The pandemics of the past century have always been caused by viruses, which evolved as different types of virus in a host animal had formed into a genetically new type. Due to the numerous H5N1 infections in birds that occur worldwide, it may seem to be only a matter of time and chance until a human-to-human transmission occurs, the researchers said.

In the trade magazine „Science“ Further studies on this topic are presented. In another study, researchers report that two viruses with the necessary mutations for human-to-human transmission have already been found in the field. Using a mathematical model, they examined which factors make more mutations more likely and which make them less likely.

Bird flu claimed fatalities
In Hong Kong, people infected with the bird flu virus in 1997 for the first time. More than 600 sick people have been registered to date, all of whom have had close contact with poultry. About half of the patients died as a result of the infection.

Avian Influenza is the name given to infections with influenza A viruses of the H5N1 type. The letters „H“ and „N“ indicate protein pieces on the envelope of the viruses. The variants are numbered. First registered in Asia in the late 1990s, the H5N1 virus spread to Europe, Africa and the Middle East. Particularly dangerous is the pathogen for birds, from which a large part of the affected animals dies.

What symptoms do people show when taking bird flu??
After a hitherto not clearly defined incubation period, which experts indicate with two to 17 days, usually the usual symptoms of flu appear. In addition to very high fever sufferers suffer from cough, shortness of breath and sore throat. In some cases diarrhea, abdominal pain and vomiting occur. In the course of the disease, it often leads to pneumonia and stomach and intestinal complaints. Some patients also suffer from kidney failure, which can lead to kidney failure. If the infection is fatal, it is usually caused by lung or multiple organ failure. (Ag)

Read about:
Study on bird flu supervirus published
H5N1 supervirus studies are published
WHO calls for publication of supervirus data
Dangerous bird flu virus or harmless?

Picture: Aka