No all-clear for bird flu virus H7N9

Doctors give no all-clear with the bird flu virus H7N9

09/04/2013

The hitherto unknown bird flu virus H7N9 has killed seven people in China so far. Further infections have been confirmed, meanwhile there are already 24 patients. Chinese authorities and the World Health Organization (WHO) provide an assessment of the situation.

What does H7N9 mean?
The new bird flu virus is called "A (H7N9)", where A is the flu type A. The proteins of the virus envelope (hemagglutinin and neuraminidase), of which there are different structures, are abbreviated to H and N. Normally, infection with these virus combinations takes place in birds. Although infections from the subgroup H7 were already detected in humans, but not in combination with N9. This variant, which was frequently found in recent days in China, has not yet occurred in humans.

possibilities of infection
It was not yet possible to determine exactly how those affected became infected, as the source of the infections is still unknown. The virus has been detected in several birds: in Chinese Shanghai in pigeons and in other cities in quail. Much of China's population is rural, and often comes into contact with various animals. On Chinese markets, there are often various live birds to buy. In some of the infected patients close contact with animals is considered safe. About cases that have become known, a special website of WHO provides information.

What danger does the new virus harbor??
Basically, there is a pandemic risk theoretically for any influenza virus of an animal that can also infect humans. This refers to a cross-continental spread of a disease. However, animal influenza viruses have not yet led to a pandemic despite individual evidence in humans. But to assume that they are harmless, would be wrong and the resulting fear is quite understandable. For example, since 2003, there are more than 600 people infected with the avian influenza H5N1 virus. There were 371 deaths. It is still unclear whether a pandemic could be triggered by H7N9. But if there is evidence for a human-to-human transmission, the risk would skyrocket. However, according to Chinese authorities there is no proof of this.

There is a danger with China travel?
There are few confirmed infections and the World Health Organization has not issued travel restrictions. Nevertheless, Chinese airlines are already seeing significant drops in passenger numbers in the affected cities. Since there are no indications of possible links between Chinese products and the cases of illness, the WHO also advises not to trade restrictions.

So far no counter vaccination
There is still little information about patients' symptoms today. It is known that in most infected people came to a severe pneumonia. Normally, you can treat a type A flu with drugs (neuraminidase inhibitors). There is also evidence that these act at an early stage of, for example, A (H5N1) infections. For the virus combination H7N9, however, there are still no findings as to whether such drugs are effective. So far there is no vaccine against the virus.

Information from the World Health Authority
If people with suspected flu symptoms are reported to the Chinese authorities and the infection is confirmed, contact persons are also tested and monitored. In China, the sale and trade of birds has been severely curtailed or banned, markets have also been closed and thousands of animals have been culled as a precautionary measure. However, according to the WHO, eating well-cooked meat of healthy birds is not safe, as flu viruses do not survive at temperatures above 70 degrees Celsius. However, it is warned about the consumption of sick animals and direct contact with animals in markets. In some cities of China, hospitals have been alerted and advised to store large quantities of necessary medicines. So far there are no known cases of infected persons in Germany. The further development must be closely monitored in order to recognize possible dangers early on. The World Health Authority provides detailed information on the bird flu virus via a website. (Ad)

Picture: Gerd Altmann