While the threat of a bird flu pandemic still looms large, a new study warns that farmers, veterinarians, meat processing workers and other people who are exposed to pigs are at heightened risk of contracting swine influenza.
The study, which is published in the Jan. 1 issue of the journal Clinical Infectious Diseases, describes that the physical makeup of the pigs allows them to contract and spread influenza viruses to and from other species, such as humans and birds.
Due to their susceptibility to influenza virus infections from other species, pigs can also serve as 'mixing vessel hosts' that can produce new influenza virus strains that could pose a risk to human health.
For the study, the researchers examined farmers, veterinarians, meat processing workers and a control group of people who had no occupational contact with pigs in Iowa, the state with the highest swine production.
They found that, of the four groups, farmers were most likely to be seropositive, i.e., to have antibodies in their blood against swine influenza, indicating previous infection with the virus. Veterinarians also had increased odds of seropositivity. Meat processing workers had elevated antibody levels as well, though the odds were not as high, perhaps due to the workers' limited exposure to live pigs.
However, the authors, Gregory Gray and Kendall Myers, of the University of Iowa, stress that despite the possibility for human infection with swine influenza, people shouldn't panic, as it is expected that the normal clinical course of swine influenza infections in humans is mild or without symptoms.
The authors, however, suggest that pork should be washed thoroughly and people involved should practice good hand washing. Also, increasing surveillance for influenza among swine workers is one key component of helping to prevent an epidemic.