Turkey cases show bird flu targets children and youth

The WHO reported on 10 of the 12 confirmed avian influenza cases in Turkey, where the virus struck only children aged younger than 16, with a median infection age of 14 years.

The WHO’s Weekly Epidemiological Record of 27 October stated: “To some extent, this reflects the same age distribution observed globally, where 50.5% of cases occurred among people aged <20 years, and it suggests that age-related factors may influence susceptibility to the disease," the report states.

Of the case-patients described in the report, all of those who died were teenagers, while all the survivors were younger children, aged three to nine years. “This reflects closely the global situation where the highest case-fatality rate (73%) has been observed in the 10-19-year age group,” the article says.

In spite of the fact that the 10 cases in the report involved family clusters, investigators concluded that person-to-person transmission in the families was unlikely. This was because of the timing of the infections, which indicated that the patients feel ill because of individual contact with a common environmental source.

Turkey was the first country outside Southeast Asia to report human cases. A total of 21 human H5N1 cases had been reported in January on the basis of tests in a Turkish laboratory, but only 12 of these were confirmed by the WHO because the remainder were not confirmed in reference labs recognised by the organisation.