Hepatitis B Virus Found in Sweat of Olympic Wrestlers

IZMIR, Turkey, March 1 -- Hepatitis B virus testing and immunization should be mandatory for professional or Olympic athletes participating in contact sports, a small Turkish study suggests.

Nearly 13% of Turkish Olympic wrestlers whose blood was tested were found to have occult HBV infection, said Selda Bereket-Ycel, M.D., of the Celal Bayar University here, online in the British Journal of Sports Medicine.

In many of the infected wrestlers, the virus was detected in their sweat as they trained, which suggests it might be easily transmitted to fellow wrestlers, the study found.

The study included 70 wrestlers, ages 18 to 30. They underwent blood tests for HBV surface antigen with a standard, commercially available monoclonal enzyme immunoassay. Their blood and sweat were also tested with a more sensitive polymerase chain reaction (PCR) assay able to detect minute quantities of HBV DNA.

None of the wrestlers was positive for the HBV surface antigen.

However, nine (13%), met the conditions of occult HBV infection: the standard surface antigen blood test was negative, but the more-sensitive PCR test was positive for HBV DNA. Blood levels of HBV DNA ranged from 88 copies/mL to 9,700 copies/mL.

Furthermore, eight wrestlers (11%) had detectable levels of HBV DNA in their sweat. Sweat levels of HBV DNA ranged from 2.4 copies/mL to 7,500 copies/mL. Although a few wrestlers were positive for the PCR blood test but not the sweat test, the correlation between HBV levels in the blood and sweat samples was significant (P