Researchers have taken a step toward estimating the risk of disease transmission from wild meat consumption.

The team, including members of the Wildlife Conservation Society, have presented a framework to quantify the risk of zoonotic disease transmission in the Lao People’s Democratic Republic (Laos) bushmeat system and help improve understanding of the disease risk from such products.

The conceptual model takes into account conservation, food safety, food security, culture and traditions. The team also conducted surveys of wildlife vendors and consumers as well as direct observations aimed at filling information gaps identified during development of the model.

Zoonotic diseases, or zoonoses, are caused by infections that spread between animals and people. A recent example is two people in Mongolia dying from the plague after eating raw marmot meat. Bubonic plague is caused by the Yersinia Pestis bacteria. People infected with zoonotic diseases can transmit the infections to other humans, depending on the pathogen.

Every year in the United States and Canada, people contract infections from handling and eating wild game such as rabbits, deer, birds and wild pigs. Some of the infections can be avoided by use of proper slaughter, dressing and cooking techniques.

The bushmeat study published in the Science of The Total Environment journal looked at markets in Laos and noted high contact rates between consumers and bushmeat, which could add to the risk of disease transmission.

Researchers recommended use of quantitative risk analysis as a tool for multi-disciplinary data integration to evaluate the multiple trade-offs of the bushmeat system. Risk assessments supported by quantitative information could help evidence-based decision making.

Vendor and consumer interviews
All 35 wildlife vendors interviewed were females ranging in age from 25 to 65. Two reported hunting the animal themselves, while the rest purchased animals directly from hunters, from another vendor, or from a middleman, indicating most of the wildlife sold in the markets had already been in the possession of at least two people before consumers. Vendors reported selling live and dead animals.

Species reported to be the most purchased by wildlife consumers were squirrels, wild birds, wild boar, and muntjac, which is a type of deer.

Based on estimated distributions of the frequency of bushmeat consumption and amount of meat per purchase, the simulation indicated the median yearly weight of purchased bushmeat per consumer was 32  kilograms, or about 70.5 pounds.

Consumer survey results about the health risks of handling, preparing and eating wildlife included, in round numbers, these answers:

  • 28 percent said there is a high risk;
  • 22 percent said there is a low risk;
  • 17 percent said there is no risk at all; and
  • 32 percent said they didn’t know.

When asked about what disease they were referring to Trichinella, parasites, anthrax and brucellosis were mentioned.

The proportion of respondents saying they would stop eating wildlife should they learn they could get a disease from it was 84 percent for those that had prior knowledge of wildlife disease and 66 percent for people who did not.

Only a third of consumers were aware of diseases transmitted from wildlife to humans. The researchers concluded this low level of awareness of zoonotic disease suggests there may be opportunities to increase knowledge, but it was unclear if greater knowledge of disease would impact consumption behavior.

Although the vast majority of respondents, 92 percent, reported eating the meat well done, consumption of raw meat and blood for traditional Lao Larb dishes is of particular concern, according to researchers.

Most wildlife consumers reported they would be very likely to stop consuming such meat if they faced a fine from enforcement authorities. Law enforcement appeared ineffective with only about half of vendors reporting halting trade activity after intervention from the authorities. Half of those only stopped for up to three days.

Demographic data on urban consumers suggested eating bushmeat was motivated by dietary preference and tradition rather than nutritional needs.

The study was funded by the European Union under the Innovate program and the Lacanet project

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