Researchers investigate whether simian foamy virus can be transmitted through blood transfusion

Oct 25 2004

Public Health Agency Canada researchers have investigated whether simian foamy virus can be transmitted through blood transfusion.

Using an animal model, researchers demonstrated that simian foamy virus can be transmitted through blood from one non-human primate to another. Although this virus is not known to cause disease or health conditions in people or animals, this new research identifies an emerging issue related to the safety and adequacy of Canada's blood supply.

Simian foamy virus is a retrovirus that integrates into the host genome resulting in permanent life-long infections. It is commonly found in non-human primates (i.e. monkeys and apes). Although people with exposure to certain types of non-human primates can become infected with simian foamy virus, the general population is not at risk for simian foamy virus infection.

Several studies show that approximately 3 percent of people working with non-human primates are infected with simian foamy virus. The majority of people were either bitten, scratched or had skin punctures from needle sticks. So far, there is no evidence of illness in the people infected with the virus who have been followed for up to 20 years and no evidence that they can transmit the virus to others.

In addition, the Public Health Agency of Canada has completed an assessment of the risk of simian foamy virus to the blood supply. The Agency has advised Health Canada that although there are no known risks, it would be prudent to take action to ensure that simian foamy virus does not enter the blood system.

As the blood system regulator, Health Canada is considering action to reduce the potential for entry of simian foamy virus in the blood supply. This could include precautionary measures to screen for people who may be at risk of having simian foamy virus. Options include asking those who work closely with non-human primates to not give blood, or screening them out in the interview process before a donation. Once the new scientific information has been fully analyzed by the Public Health Agency and by Health Canada, and that the impact of potential risk mitigation measures on the safety of the blood supply have been fully evaluated, Health Canada will make a decision on any necessary precautionary measures.

The Public Health Agency of Canada would like to remind people who work with animals to follow occupational safety precautions to minimize their risk of exposure to simian foamy virus. Occupations that have some risk of infection include people who work in zoos, public or private biomedical research institutions and animal sanctuaries.

Based on current available information, pet owners of monkeys are not at risk of exposure to simian foamy virus because the New World monkeys usually kept as pets are not known to transmit this virus. However, if pet owners are bitten or scratched, they should follow standard first aid precautions. As with other animals, other infections are possible. Signs of infection, or if the animal is ill, should prompt medical consultation.

No diagnostic test is currently available for human simian foamy virus infection, and since no illness has been associated with infection, there is no need for exposed people to be tested. As noted, the general population is not at risk for simian foamy virus infection.

The Public Health Agency of Canada will continue to examine this public health issue as new information becomes available and will continue further research in this area.