Link Found Between Hepatitis A Spread and Small Mammals

Unsanitary living conditions promote spread of the virus.

Researchers at the University of North Carolina at Chapel Hill, have found a link between small mammals and the spread of hepatitis A (HAV) to humans.

Although an HAV vaccine was created in 1995 and reduced a substantial amount of cases in the United States, problems still persist in third world countries where HAV is rampant. The World Health Organization estimates that in countries where HAV is endemic, that all children are infected before the age of 9 due to unsanitary living conditions.

"Prior to this study, we had no understanding of the origins of HAV, an ancient and common threat to health in many regions of the world," said one of the study’s authors Stanley M. Lemon, MD. "Now we know that it evolved among small mammals such as bats, and spread from them to humans in the distant past."

In testing 15,987 samples that were collected from 209 different mammal species around the globe, Lemon and his team found that HAV-like viruses that were closely related existed in bats, rodents, shrews, and hedgehogs.

"Our study exemplifies the utility of looking beyond phylogenetic criteria alone when conducting risk assessment for emerging RNA viruses and the need to include functional, ecologic, and pathogenic analyses of animal reservoirs," said study author Jan Felix Drexler, MD. "Next steps may include efforts to grow these viruses in cell culture and functional analyses to assess their risk of being transmitted to primate hosts."