LONDON, Ont. -- Public health officials are warning customers of a nail salon in London, Ont., that they may have been exposed to blood-borne infections after a client tested positive for hepatitis B.

The Middlesex-London Health Unit issued an alert Wednesday warning clients of Cali Nails in the White Oaks Mall that they contact their doctors about getting tested for HIV, hepatitis B and hepatitis C.

Mary Lou Albanese, the manager of the health unit's infectious disease control team, says a customer who contracted hepatitis B went to the salon for a manicure and pedicure.

She says her agency is issuing the advisory for anyone who visited the salon between May 4, 2017, and Jan. 5, 2018.

Albanese adds it is difficult to pinpoint exactly where the person contracted the infection, but says officials felt a public alert was necessary after inspectors logged repeated infection-control infractions at the business.

Hepatitis B, a virus transmitted through contact with the blood or other body fluids, attacks the liver and can cause both acute and chronic disease. In Ontario, children receive the vaccine to protect against the virus in Grade 7.

"Although the risk is generally low, inadequate infection prevention and control practices in personal service settings, such as nail salons, barber shops, spas, or tattoo and body art shops, can result in the potential transmission of blood-borne infections, as well as common skin infections," the health agency's public warning said. "It is important to note; it may be impossible to determine whether any positive blood tests resulted from procedures performed at a particular location or if they are due to other exposures."

Cali Nails owner Randy Tran said the Middlesex-London Health Unit did not tell him they would be issuing the warning.

Health officials closed the salon last Friday evening until Monday afternoon for the inspection and to provide training to staff, Tran said.

He said he asked health officials to provide details about the infected person's visit to his salon, but he said they refused.

Albanese said the agency cannot release information on the infected person for privacy reasons.

Asked why the health unit suggested testing for HIV and hepatitis C, Albanese said the purpose is to get people to speak to their health-care providers about their risk of infection.

"When we send out (a warning) like this, we always err on the side of caution," she said. "And when we talk about blood-borne infections we always talk about those three."

Albanese said HIV is the lowest risk, adding there is a higher risk of contracting hepatitis at places such as nail salons and tattoo parlours.