H5N1 Re-Emerges In Ivory Coast
Recombinomics Commentary
November 25 2006
Ivory Coast declared a new outbreak of the deadly H5N1 strain of bird flu on Thursday, the first in the West African country since it was first detected there in April.
Two turkeys from a flock of 20 were found dead on Nov. 9 in Abatta, a lagoon-side village on the outskirts of the economic capital Abidjan. Around eight more died over the next few days, a government veterinary official said.
The above comments indicate the Qinghai strain of H5N1 has re-emerged in the Ivory Coast. This outbreak is likely linked to migratory birds. The announcement is much earlier than last season, but last season's announcements were likely considerably delayed. Most countries announced H5N1 after the deaths of patients in Turkey at the beginning of 2006. However, H5N1 was confirmed in Romania and Turkey in October, 2005 and recent sequences from Egypt indicate the Qinghai strain was in wild birds in Egypt in December, 2005.
This season, H5N1 has already been confirmed in the Ukraine, Egypt, and Sudan, so H5N1 throughout Africa is not unexpected. However, although large wild bird die-offs have been reported in recent weeks, the above report is the only confirmation in western Africa, and many countries that failed to detect H5N1 last season, have also failed this year even though there are die-offs and these countries are adjacent to H5N1 positive countries.
Similarly, countries in the Middle East have failed to report outbreaks.
These reporting failures are cause for concern. This season, H5N1 is again being transported and transmitted by migratory birds. In addition to the above reports, South Korea has now confirmed H5N1. The mention of migratory routes suggest that the cleavage site matches the Qinghai strain, as did the isolates from last season from Russia, Kazakhstan, Mongolia, India, Afghanistan, and all reporting countries in Europe, the Middle East, and Africa.
It is unclear why these countries fail to detect H5N1. Some countries, such as the United States and Canada, have focused the H5N1 testing on live birds, even though the vast majority of wild birds detection has been in dead wild birds. Many countries in Europe have found H5N1 only in dead wild birds, which raises serious questions about the worldwide surveillance of H5N1.
As the H5N1 infected birds migrate south, more infections are expected.
Serious testing of dead wild birds would be useful.
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