July 3, 2009

Defunct Protein Explains Swine Flu’s Infection Pattern

Though the swine flu has continued to spread across the planet in recent weeks, health experts have observed an infection pattern that tends to produce smaller, localized outbreaks rather than massive, wildfire-like epidemics.  Researchers at the highly-esteemed Harvard-MIT Division of Health Sciences and Technology now say they have pinned the fortuitous trend on a defunct viral protein.

The researchers point to a binding protein on the surface of the H1N1 virus that is not very adept at doing its job"”holding tight to cell receptors in the human respiratory tract.

"While the virus is able to bind human receptors, it clearly appears to be restricted," explained Ram Sasisekharan, the report's lead author of the report.

He also noted that the recent protein discovery, is entirely consistent with the spread of infections observed thus far. The majority of outbreaks have occurred in relatively small, contained clusters, rarely spreading in mass beyond family units and schools.

Researchers working with the virus have also observed that it is far more active in the gastrointestinal tract than typical flu strains, which would explain the increased incidence of vomiting and intestinal pain compared with seasonal varieties.

Still, despite H1N1's apparent Achilles heel,  health experts caution that influenza viruses are notorious for the speed and unexpectedness with which they can mutate, meaning that the swine flu's deficient binding ability could adapt at any time.

Since the H1N1 virus was first identified in April, it has killed more than 300 people and infected some 70,000 according to World Health Organization statistics.  Since June 11, the virus has carried the heftiest warning label that the WHO could bestow on it: a level 6 pandemic alert.

As the inhabitants of the Northern Hemisphere are enjoying the warm weather of peak summer months, flu season is in full swing for their southern counterparts in South America, Australia and parts of Africa.

In Argentina, ubiquitous outbreaks of H1N1 have prompted officials to give students an early vacation, while one particularly hard-hit province has been forced to declare a public health emergency.

Kathleen Sebelius, Secretary of the Health and Human Services, announced on Thursday that the U.S. government will supply nearly a half a million treatments of the anti-viral medicine Tamiflu to the Pan-American Health Organization in an effort to help battle the swine flu in Latin America and the Caribbean.

"Viruses know no borders," said Sebelius in conference with Mexican health officials. "The U.S. recognizes that a novel virus such as the H1N1 is a burden borne by all nations, and all of us have a responsibility to help support one another in the face of this challenge."

Despite being out of immediate danger, some countries in the Northern Hemisphere are already concerned about the possibility of a resurgent outbreak of the virus as soon as cooler weather begins to arrive.

On Thursday, the U.K.'s health minister Andy Burnham said that the agency's projections showed that the country could potentially expect some 100,000 new swine flu cases a day by the end of August.  In light of their grim predictions, he has recommended an urgent revamping of the nation's strategy for dealing with the virus.


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