Two pieces of bad news were announced over the weekend: H5N1 has crossed into the territory of the European Union (EU) and H5N1 resistant to Tamiflu has been detected in a Vietnamese patient.
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| Health workers are disposing of geese in Ceamurlia de Jos, the site of the first H5N1 avian influenza outbreak in Romania. |
On October 15, the Romanian Ministry of Agriculture announced that test results from the UK confirmed that H5N1, the virus responsible for over 60 deaths in Asia, has appeared in Eastern Europe, specifically in wild ducks in Romania. This announcement came a week after H5N1 was detected at a poultry farm in Turkey, where 5,000 birds have been culled so far.
The Romanian Minister of Agriculture urged calm, stating that although the virus spreads easily among birds and poultry, it has not yet been easily transmitted between humans. The northeastern region of the country is currently under quarantine, and all vehicles entering and leaving the area are being disinfected. A total of 20,000 birds will be culled to prevent the spread of the virus.
In light of this situation, the World Health Organization (WHO) has reiterated its warnings: Although the virus is not easily transmitted between humans, H5N1 could mutate into a pandemic strain that could kill millions. According to Klaus Stoehr, countries not yet affected need to recognize that H5N1 will likely spread further and should prepare to combat an outbreak.
In another development, American scientists collaborating with their colleagues in Vietnam and Japan announced on October 14: the avian influenza virus isolated from a girl in Vietnam has shown resistance to Tamiflu.
The 14-year-old girl was prescribed Tamiflu in February 2005 as a preventive measure. Although she did not have direct contact with infected poultry, at that time she was caring for her 21-year-old brother, who was suspected of being infected with avian influenza. The virus isolated from her was identical to that found in her brother. The girl has since recovered, but this case suggests that she may have contracted the virus from her brother rather than directly from poultry.
Recently, scientists from the University of Wisconsin-Madison discovered that multiple H5N1 virus strains in samples from the girl had developed genetic mutations that rendered them resistant to Tamiflu. Furthermore, the entire mixture of H5N1 viruses from her samples also exhibited some level of resistance to this medication. Tamiflu, also known as oseltamivir, is considered the first line of defense against a future influenza pandemic, with countries worldwide spending billions of dollars to stockpile this drug.
According to Professor Yoshihiro Kawaoka from the University of Wisconsin-Madison, this discovery indicates that health officials should consider stockpiling other antiviral medications, such as zanamivir, which is an older antiviral drug. Medications like Tamiflu, when used in conjunction with quarantine measures, could slow the spread of the virus until a vaccine can be produced. However, Tamiflu and other antiviral medications cannot replace vaccines; only effective vaccines can provide immunity against the virus.
Researchers advise that Tamiflu should only be prescribed to patients infected with the avian influenza virus and that the virus should be regularly monitored to see if it is mutating and developing further resistance to treatments. They also added that this finding does not mean that drug-resistant strains of H5N1 will efficiently and successfully infect others. However, this research raises awareness that drug resistance is an issue, highlighting the need for global surveillance measures.
Minh Sơn (Sourced from THX, BBC, Fox News, Reuters)
