About 203,000 people around the world died of flu and respiratory problems during the 2009 H1N1 “swine flu” pandemic, according to a new study funded by the World Health Organization.
Deaths from heart failure and other secondary consequences of the flu pushed the overall toll to about 400,000, according to the study, published online on Tuesday by PLoS Medicine.
The estimated death toll closely matches that of a study published in June 2012 by the Centers for Disease Control and Prevention. That study, based on early data, estimated that 201,000 people died of flu and respiratory causes and another 83,000 died of related cardiac problems.
Both counts were many more than the 18,449 laboratory-confirmed cases that the W.H.O. stood by as its official count in 2009 because agency officials were reluctant to guess at fatality rates. Some politicians, particularly in Europe, used the low official W.H.O. death rate to argue that fear of the pandemic had been overblown. They accused vaccine companies of fanning the public’s fears to sell more of their product.
Dr. Lone Simonsen, an epidemiologist at George Washington University’s School of Public Health who led the new study, said she found it “comforting” that both studies had reached similar conclusions.
The C.D.C. study was based on illness rates from 12 countries and death rates from just five.
Dr. Simonsen’s study used data from 26 countries, extrapolating from that to arrive at a figure for the entire world. The data included national death rates from 21 countries accounting for about 35 percent of the world’s population; for example, the countries included China but not India, and South Africa but not the rest of Africa.
Dr. Simonsen described the rival study as “nimble” while hers was “time-consuming.”
The C.D.C. study, she argued, overestimated deaths in Africa and Asia and underestimated them in Latin America. She came to that conclusion largely from the striking differences in how lethal the disease was in different regions.
The flu — a novel combination of a gene from a Eurasian pig flu with an established set of genes from human flu, bird flu and North American pig flu — was first isolated in Mexico in April 2009. In that country, Argentina and Brazil, it was 20 times as likely to kill victims as it was in places where cases peaked later in the year, including New Zealand and Australia, where it peaked in August, and Europe, where it peaked in the winter of 2009-10.
Brazil’s data was particularly enlightening, she said, because infection and death rates there were much higher in the temperate, relatively wealthy south than in the impoverished, tropical north. That suggested, she said, that the flu threat was more dependent on cold weather than on income, which affects the quality of medical care victims get.
Enviado por Fernanda Aguilar Perez