Humans contract rat hepatitis

HONG KONG — Researchers said Wednesday they have found a second patient in Hong Kong who contracted a strain of hepatitis carried by rats, in what appears to be the first known human cases in the world.

The finding surprised the researchers, though it wasn’t immediately clear whether there were significant implications for human health.

“Because the rat ... strain is very different from the human strain, people think it wouldn’t be able to jump to humans,” said Siddharth Sridhar, one of the principal researchers at Hong Kong University. “This was a clinical discovery.”

The first case came out in September. Researchers confirmed that a 56-year-old man had a hepatitis E strain previously known only in rats in Vietnam.

The second case was found after blood samples from more than 70 hepatitis E patients were tested.