WASHINGTON, Dec. 17, 2009–A study conducted by U.S. Department of Agriculture (USDA) scientists provides additional confirmation that meat and tissue from pigs exposed to two strains of the 2009 novel pandemic H1N1 virus did not contain virus. The results were published today in the Public Library of Science’s online journal, PLoS ONE. The study was conducted by scientists with USDA’s Agricultural Research Service (ARS) at the agency’s National Animal Disease Center, part of the USDA National Centers for Animal Health in Ames, Iowa. ARS is the chief intramural scientific research agency of USDA.
“This research provides additional reassurance for consumers about the safety of pork,” said Edward B. Knipling, ARS administrator. “The information contained in the study will also benefit customers of U.S. pork products, both here and abroad.”
ARS scientists received samples of the 2009 novel pandemic H1N1 (H1N1) virus in May from the U.S. Centers for Disease Control and Prevention. The virus samples came from humans in California and Mexico who had become infected with this H1N1 virus.
Researchers inoculated a group of 30 five-week-old pigs with the virus to determine the pigs’ susceptibility to H1N1. Five pigs that were not inoculated with the virus served as a comparison or “control” group. The pigs were observed daily for clinical signs of illness and then were euthanized at three, five or seven days after inoculation.
Researchers tested tissue samples of the pigs’ lungs, liver, muscle, spleen and other vital organs using the most sensitive tools available to detect the presence of live virus and nucleic acids from the virus. The inoculated animals showed signs of upper respiratory disease consistent with influenza, however there was no evidence that the virus had spread to any other parts of the body.
These findings about the safety of pork from pigs previously infected with the 2009 novel pandemic H1N1 virus support recommendations of the World Health Organization that pork harvested from swine that had been infected previously and had recovered from the virus can be safely handled or eaten, following basic hygiene practices for handling of meat.
This research supports the USDA priority of ensuring food safety. Additional information about USDA’s H1N1 efforts is available at www.usda.gov/H1N1flu