WHO working on formulas to model swine flu spread

Jul 01, 2009 By FRANK JORDANS , Associated Press Writer

(AP) -- The World Health Organization said Wednesday it is working to mathematically model the spread of swine flu in an attempt to better understand how the outbreak developed from a handful of cases to a global epidemic in less than two months.

WHO brought together over 20 independent experts beginning Wednesday for the three-day meeting in Geneva.

"They will be working together to describe and predict the behavior and impact of the pandemic, and demonstrate potential outcomes of proposed intervention efforts," spokeswoman Aphaluck Bhatiasevi told The Associated Press.

The meeting comes as it becomes clearer that actual case numbers may be far higher than the agency's tally of officially diagnosed infections.

According to WHO's latest update Wednesday, a total of 77,201 confirmed cases and 332 deaths have been reported in over 110 countries.

But U.S. health officials said last week the number of Americans infected with the new A(H1N1) virus may be as high as 1 million. The estimate by the U.S. was based on mathematical modeling and surveys by health officials.

"We're now probably off by orders of magnitude in terms of the real number of cases versus the number of diagnosed cases," said Andrew Pekosz, a expert at Johns Hopkins University in Baltimore.

In countries where the virus has firmly established, counting individual cases doesn't paint an accurate picture of the disease anymore, he said.

Still, information about confirmed infections can be fed into mathematical models to predict future developments and detect anomalies.

"A jump from one patient to 60 patients isn't a concern, but a jump from one to 300 shows you there's something going on that needs to be looked at carefully," said Pekosz.

On the other hand, "if you've got 100 cases and then week later you've got 150, most mathematical models would indicate that either the infection in your country isn't behaving normally, or you're not diagnosing all the cases that are occurring."

WHO's Bhatiasevi said the experts would be looking not just at case numbers, but also at how many severe infections have occurred and which measures have helped stem the spread of the disease.

This will help WHO advise countries on how to respond to the pandemic and target their supply of anti-viral medication and later vaccines, when those become available.

During the of SARS in Asia and foot and mouth disease in Britain mathematical models were applied after the event, said Pekosz.

may offer the first opportunity to apply the formulas as a is occurring, he said.

©2009 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

Explore further: How the world is underestimating Ebola: WHO

add to favorites email to friend print save as pdf

Related Stories

UK's attempts to stop swine flu called flawed

May 21, 2009

(AP) -- Flu experts are looking very closely at Britain - and some have decided that the U.K.'s swine flu-fighting tactics are seriously off the mark and may be hiding a much larger outbreak.

WHO meets on production of swine flu vaccine

May 14, 2009

(AP) -- As swine flu cases hit 6,500 worldwide, World Health Organization officials were meeting with vaccine manufacturers and other experts in Geneva on Thursday to discuss making a vaccine to fight the virus.

WHO gets ready declare a swine flu pandemic

Jun 10, 2009

(AP) -- The World Health Organization is gearing up to declare a swine flu pandemic, a move that could trigger both the large-scale production of vaccines and questions about why the move was delayed for ...

Recommended for you

How the world is underestimating Ebola: WHO

5 hours ago

The Ebola epidemic tearing through western Africa is by far the deadliest known outbreak of the disease, yet the magnitude of the spread is believed to be severely underestimated.

Last Ebola-free region of Liberia falls to virus

5 hours ago

Every region of Liberia has now been hit by Ebola, officials said Friday, as the World Health Organization warned the fight against the worst-ever outbreak of the killer disease would take months.

Ebola death toll rises to 1,427: WHO

16 hours ago

The death toll from the Ebola outbreak sweeping through west African countries has risen to 1,427 out of more than 2,600 cases, the World Health Organization said Friday.

User comments : 0