2009 Swine Flu Pandemic May Have Killed Ten Times As Many People As Originally Thought

CREDIT: AP Photo/Chiang Ying-ying

Swine Flu Detection

CREDIT: AP Photo/Jeff Roberson

The global H1N1 swine flu pandemic of 2009 may have killed ten times as many people — or somewhere between 123,000 to 203,000 throughout the world — than originally estimated by the World Health Organization (WHO), according to a new study published in PLOS Medicine and funded by the global health agency.

The WHO originally estimated that approximately 18,449 people died of swine flu over the course of the pandemic. But those estimates were based solely on swine flu cases that were definitively confirmed in labs, likely undershooting the flu’s true mortality rate.

“[A]s is the case with all influenza epidemics, the true mortality (death) burden from H1N1 is substantially higher than these figures indicate because only a minority of influenza-related deaths are definitively diagnosed by being confirmed in laboratory,” explained the researchers. “Many influenza-related deaths result from secondary bacterial infections or from exacerbation of preexisting chronic conditions, and are not recorded as related to influenza infection.”

The new study relied on data from 60 researchers across 26 countries and estimated the far higher swine flu mortality rate based on local respiratory-problem related deaths. The authors also note that their updated analysis may still be under-counting the total number of swine flu deaths because it only examined data from the first nine months of 2009 and excluded non-respiratory flu-related mortality.

Although cases of swine flu are still popping up in places like India, most countries are more concerned about a different strain of the virus this flu season: the H5N1 bird flu.

Last Friday, the Food and Drug Administration (FDA) approved an H5N1 vaccine for national stockpile in case the strain develops the capacity to spread directly from human-to-human contact. Chinese scientists announced that they had identified the first human case of a slightly different flu strain, H6N1, that could jump directly from chickens to human, raising concerns that it may also be able to transmit between humans.

Doctors and public health experts say the best ways to avoid catching or spreading the flu are to get vaccinated, avoid large crowds when you’re sick, wash your hands regularly, and clean up surfaces that might trap germs with disinfectants.