At least 14 people in rural Turkey have been infected with the H5N1 avian influenza strain, and at least two have died, the World Health Organization (WHO) said in a press release tonight that confirmed statements by Turkish officials over the past few days. The high toll is a dramatic new landmark for the almost unstoppable flu strain. But WHO says the virus apparently has not mutated to become more dangerous. "We get the feeling that it's still very similar to the situation in Asia," says Guenael Rodier of WHO's European office in Copenhagen, who leads an investigative team in Turkey.
H5N1 has been raging in Asian poultry flocks for the past 2 years, sickening 140 people and killing more than 70 (ScienceNOW, 13 October 2005). It has also been found in poultry in Russia, Mongolia, Romania, Croatia, and Turkey--brought there, many believe, by migratory birds. But until recently, no human cases had been reported outside of Asia.
Four of the 14 cases have been independently confirmed by a laboratory in the United Kingdom, according to the WHO statement. The agency expects the rest to be confirmed as well, because the quality of testing at the National Influenza Centre in Ankara is high. The toll seems set to rise further; at least one fatal case that is not in WHO's tally is presumed to be an H5N1 victim as well; the patient, a young girl, was a sibling of two confirmed H5N1 fatalities. Many more people have been hospitalized with suspected or possible H5N1 infections.
The 10-member WHO team, which includes experts in epidemiology, diagnosis, treatment, and veterinary science, arrived in Turkey's eastern of province of Van yesterday and began visiting hospitals and talking with clinicians. So far, the disease appears to have stricken only people who have been in close contact with dead or ill poultry, Rodier says, often members of the same family. The preliminary findings don't suggest that H5N1 has become more easily transmissible from poultry to people, or between humans, he says. (The latter scenario could lead to an influenza pandemic.)
But the high number of confirmed and suspected cases does suggest that H5N1 is much more widespread in birds in Turkey than believed, giving it more chances to jump the species barrier. Besides Van, human cases have occurred in the north-central provinces of Kastamonu, Corum, and Samsun, and in central Ankara province.
More aggressive monitoring and control efforts, as well as education on how to safely handle dead and infected poultry might have prevented some of the infections, Rodier says. "It's too bad that it took human cases to trigger more awareness."
Two more international experts were traveling to Ankara today to join the team on behalf of the European Centre for Disease Prevention and Control (ECDC) in Stockholm.