Avian Influenza and Pandemics — Research Needs and Opportunities

As the year 2004 progressed, so did conditions favoring the start of an influenza pandemic. The first warning came in January, when Thailand and Vietnam reported fatal human cases of avian influenza caused by the H5N1 strain of influenza A virus. That strain was already notorious for its pandemic potential, revealed during an outbreak in Hong Kong in 1997 and later in a smaller number of human cases in 2003.With the H5N1 strain now endemic in birds in large parts of Asia, the probability that this potential for a pandemic will be realized has increased. Recent laboratory and epidemiologic . . .