Pandemiology

There's a really scary article in the New England Journal of Medicine this week about preparing for a pandemic. (You may not be able to see that link - I think I have a subscription through work. Maybe I will post the full text somewhere later - if I do I'll put up a link - but meanwhile here's some excerpts.)

An influenza pandemic has always been a great global infectious-disease threat. There have been 10 pandemics of influenza A in the past 300 years. A recent analysis showed that the pandemic of 1918 and 1919 killed 50 million to 100 million people, and although its severity is often considered anomalous, the pandemic of 1830 through 1832 was similarly severe — it simply occurred when the world's population was smaller. Today, with a world population of 6.5 billion — more than three times that in 1918 — even a relatively "mild" pandemic could kill many millions of people.

Influenza experts recognize the inevitability of another pandemic. When will it begin? Will it be caused by H5N1, the avian influenza virus strain currently circulating in Asia? Will its effect rival that of 1918 or be more muted, as was the case in the pandemics of 1957 and 1968? Nobody knows.

So how can we prepare? One key step is to rapidly ramp up research related to the production of an effective vaccine.....urgent needs include basic research on the ecology and biology of influenza viruses, studies of the epidemiologic role of various animal and bird species, and work on early interventions and risk assessment. Equally urgent is the development of cell-culture technology for production of vaccine that can replace our egg-based manufacturing process. Today, making the 300 million doses of influenza vaccine needed annually worldwide requires more than 350 million chicken eggs and six or more months; a cell-culture approach may produce much higher antigen yields and be faster. After such a process was developed, we would also need assured industrial capacity to produce sufficient vaccine for the world's population during the earliest days of an emerging pandemic.