The spread of avian influenza to poultry in Niger confirms officials' fears that conditions in West Africa favor further spread of the infection, the World Health Organization has reported.
There are currently no human cases of H5N1 viral infection confirmed in Africa. In Nigeria, local tests have ruled out avian influenza in three of four people with respiratory illnesses, one of which was fatal.
Concern about the potential for human infection remains high, the World Health Organization (WHO) said in a statement. “The WHO is concerned that spread of the virus to additional parts of Africa will broaden opportunities for human cases to occur under circumstances where capacities to find, diagnose, investigate, and manage cases are limited,” the organization said.
Poultry outbreaks in “numerous” other African countries are under investigation, but “throughout most of Africa, rapid detection and investigation of outbreaks are hampered by the absence of an early warning system for avian influenza in animals or humans, inadequate diagnostic capacity, and difficulties in shipping specimens, both internally and abroad, for diagnostic confirmation,” the WHO said.
In addition, economic concerns are mounting. “Backyard producers in many developing countries are losing income and are facing increased livelihood and food security risks,” the Food and Agriculture Organization (FAO) of the United Nations reported. Globally, more than 200 million chickens have been culled since the onset of the avian influenza crisis, it said in a statement.
The WHO stressed that despite a rapid increase in disease activity among birds and the infection of 174 people (including 94 deaths), proper cooking of poultry products kills the virus. No human cases have been “linked to the consumption of properly cooked poultry or poultry products,” the statement said. The FAO confirmed that poultry products cooked at or above 70°C are safe.
Meanwhile, as Sweden joined the list of European countries confirming H5N1 infection in wild birds, German authorities announced the detection of the virus in a dead domestic cat from the island of Ruegen, where the infection has already been confirmed in wild birds. The cat's infection marks the first evidence of avian influenza in a European mammal, but “there is no present evidence that domestic cats play a role in the transmission,” said the WHO. “All available evidence indicates that cat infections occur in association with H5N1 outbreaks in domestic or wild birds.”
Since 2003 there have been anecdotal reports from Southeast Asia of domestic cat infections with the H5N1 virus. Eating raw infected poultry was the most likely source of those infections, said the WHO.