Swine influenza (H1N1 strain) has now been confirmed in 8 humans, including two in the San Antonio area. None of these cases have been traced to livestock exposure at this time and all eight people have recovered. However, this situation requires heightened biosecurity practices on all swine farms in order to help prevent human-to-pig transmission.
Texas Pork Producers Association, the National Pork Board, Texas AgriLife Extension and the Texas Animal Health Commission have asked that Extension and Animal Health Commission personnel as well as all veterinarians, assist with alerting producers (regardless of size of operation) of the situation and encourage implementation of increased biosecurity practices, especially those who have employees whom may have visited Mexico recently.
Preliminary investigations indicate that in all cases there was no contact with swine.The swine influenza subtype isolated from these cases is unique and not previously recognized in either pigs or people. According to the Centers for Disease control (CDC), “This virus is different, very different from that found in pigs.” At this time there is no evidence that this swine influenza subtype is present in pigs in the United States. The National Pork Board is collaborating with the CDC and the United States Department of Agriculture (USDA) to provide information on swine influenza. Information on influenza can be found in the fact sheet, “INFLUENZA: Pigs, People and Public Health” available at http://www.pork.org/PorkScience.
Swine influenza virus in meat
The risk of illness from consuming pork is minimal. The CDC said Thursday that humans cannot contract this strain of swine influenza from eating pork.
• In pigs, swine influenza is a respiratory disease. Few reports exist supporting theories of influenza entering the bloodstream or causing systemic infection in pigs. Therefore, it is reasonable to expect that swine influenza cannot be found in pork/pork products.
• If an animal with active swine influenza infection should arrive at a harvest facility, it would not pass the Food Safety Inspection Service (FSIS) ante-mortem inspection and would be condemned as an animal not fit for human consumption.
• FSIS has stated that even if surface contamination of a product should occur, common-sense food handling and preparation practices would minimize the risk of illness as normal cooking temperatures should inactivate the virus.
• It is possible for humans to transmit some influenza viruses to pigs. And it is possible, though not common, for pigs to transmit some influenza viruses to humans.
• Interspecies infections are most likely to occur when people are in extremely close proximity to pigs.
Pork producers should work with their herd veterinarian to reduce transmission of influenza viruses:
• Influenza virus vaccination of pigs
• Influenza virus vaccination of swine farm workers
• Implement worker sick-leave policies that encourage employees to remain away from work when they are suffering from acute respiratory infections. People typically shed influenza viruses for approximately 3-7 days, with the period of peak shedding correlated with the time of most severe clinical illness.
• Maintain appropriate ventilation in the barns
• Enforce basic hygiene and biosecurity practices
• Prevent pig to bird contact. Bird-proof buildings and treat water if it supplied from an open body of water where birds and migratory fowl may be found. Separate pig and bird production to prevent any potential cross-contamination of the animals with influenza virus. Protect feed from feces of birds and migratory fowl.