Now that we are in the midst of influenza season in humans and swine, it is important to remind ourselves and our clients of the importance of vaccination and other control measures to minimize the risk of viral spread. Since influenza viruses can spread both ways between swine and people, vaccination of employees is important, as is encouraging farm employees to stay home if sick with influenza-like symptoms. Likewise, swine vaccination may help prevent clinical signs and minimize viral spread within the herd.
Continued participation in the influenza surveillance program instituted in 2010 is also important to provide animal health and public-health officials with a source of isolates to further vaccine development and diagnostic improvements. Tissues or nasal swabs from clinically sick animals submitted to the veterinary diagnostic laboratory are automatically entered anonymously into the surveillance program. Unique or novel isolates are submitted to the National Veterinary Services Laboratory for further analysis and inclusion in GenBank to allow access to researchers in human and animal health.
So far this flu season, there have been a number of reports involving the circulation of H3N2 viruses within the human population. One strain currently circulating has acquired the matrix gene from the pandemic H1N1 virus prominent in 2009.
As of November, approximately 10 human cases had been identified in Indiana, Iowa, Maine, and Pennsylvania. These cases resulted in relatively mild illnesses, with all patients fully recovering. Nine of those cases involved children and many had direct or indirect contact with pigs.
Each winter, H3N2 viruses commonly circulate in the human population, and according to the Centers for Disease Control and Prevention (CDC), this virus appears most closely related to human H3N2 viruses circulating in the early 1990s. The CDC speculates that many people born before 1990 would likely have some level of protection against this virus. This specific strain is not included in the human seasonal flu vaccine currently available. The CDC, however, has developed a vaccine seed strain for distribution to human-vaccine manufacturers.
The key points to keep in mind:
1. Get vaccinated and vaccinate at-risk swine.
2. Farm employees experiencing influenza-like symptoms should stay away from pigs.
3. Frequent hand washing helps prevent the spread of disease.
4. Continue to submit diagnostic samples from clinically sick pigs to the diagnostic lab for inclusion in the influenza surveillance program.
5. Do not transport clinically sick swine.
6. Report vaccine failures to the manufacturer and USDA Center for Veterinary Biologics (online or call 800–752–6255).
AASV board approves position statements
The AASV Board of Directors adopted two position statements during its fall meeting held October 11, 2011, in Perry, Iowa. The statements modified existing policy addressing the issues of porcine reproductive and respiratory syndrome (PRRS) virus elimination and animal welfare.
The board was presented with a request to amend the PRRS eradication position statement to reflect updated terminology (PRRS virus elimination instead of PRRS eradication) and new information regarding the economic impact of PRRS. The newly adopted statement reads as follows:
“Porcine reproductive and respiratory syndrome (PRRS) is a significant production-limiting disease of swine that is estimated to cost the North American swine industry in excess of 664 million dollars per year. Control of the disease via traditional methods has not been effective in all cases; therefore, it is the position of the AASV that elimination of the PRRS virus from the North American swine industry is the long-term goal. The AASV will take a leadership role by partnering with the swine industry to promote collaborative PRRS virus elimination efforts at the local, regional, and national levels, communicating the need and identifying sources of funding to support such initiatives, and assisting in the transfer of new PRRS-related information and technology across its membership, in order to achieve this goal.”
In other action, the board also approved revising the existing swine welfare policy at the request of the AASV Pig Welfare Committee. The committee reviewed the existing policy and proposed that it be revised with the following wording:
“The welfare of pigs is the accepted ethical and professional responsibility of all swine veterinarians. We support, assist, and educate swine caregivers in practices that promote and protect the health and well-being of pigs.
Swine veterinarians advance proper swine care by preventing and treating disease, addressing and reducing pain and distress, safeguarding animal health, and teaching good husbandry practices. We make decisions regarding animal care and well-being by combining scientific knowledge and professional judgment with consideration of ethical and societal values.
As veterinary professionals, the American Association of Swine Veterinarians and its members will continue to improve pig welfare through scientific research, education, and advocacy.”