World Health Organization to release swine flu clinical findings

National Report

-- More cases of a new multi-species strain of swine influenza are being reported globally, but there still are no public theories as to how the strain developed and why it's being spread from person to person. But the World Health Organization (WHO) will host a scientific review April 29 to try and pinpoint the virology and other clinical findings concerning the outbreak.

The new strain -- a combination of two types of swine influenza, avian influenza and human influenza - still has not shown up in any United States swine herds, according to the Centers for Disease Control and Prevention (CDC) and the U.S. Department of Agriculture Animal and Plant Health Inspection Service (USDA-APHIS). But veterinarians have been urged to be vigilant in their care of swine herds and pork producers have been advised to enhance biosecurity measures.

News outlets have been reporting that the outbreak originated in Mexico, where the most cases of swine flu have been confirmed. Some have pointed to a La Gloria, Mexico, swine operation as the root of the outbreak, but Smithfield, Va.-based Smithfield foods, which owns 50 percent of Granjas Carroll de Mexico, denies that any clinical symptoms of swine influenza have been found at the facility.

"Smithfield has no reason to believe that the virus is in any way connected to its operations in Mexico," the company said April 26, noting that the facility - which produced 950,000 hogs for brands like Weight Watchers and Butterball products in 2008 - routinely administers influenza virus vaccinations to the herd.

The WHO says it will investigate the claims at the farm, but the primary concern now is investigating and preventing the spread of the virus.

Meanwhile, more international cases are being reported, and travel advisories are in effect around the globe.

The CDC has now confirmed nearly 100 cases of swine flu in the U.S., including one death in Texas.

Border screenings are in effect along the Mexican border with the U.S., and the CDC says it has released a quarter of its stock of anti-viral drugs - 11 million courses - to combat the outbreak.

The WHO elevated its pandemic level to Phase 5 April 29, due to sustained human-to-human transmission and community-wide spread of the virus.

Check back with dvm360 for more clinical information on how swine flu is developing as it is available.