— Surfers and bodyboarders come to Imperial Beach to catch the best waves. But if they swim in contaminated waters, they’re at risk for catching something else.

Hepatitis A, along with other disease-causing pathogens, can flourish along South Bay beaches as northbound ocean currents funnel polluted water from the Tijuana River into the Imperial Beach surf.

That’s why, for the first time, health workers teamed up with environmental protection advocates Saturday to offer free hepatitis A vaccination to interested beachgoers.

Jim Knox, 61, started surfing at Imperial Beach even before the pier was built in 1963. He was one of 75 people who signed up for inoculation.

Knox said everyone should take advantage of the opportunity.

“I’ve never gotten sick from the water, but I’ve been lucky. I know plenty of other surfers who have gotten hepatitis A,” said Knox, who was shuttled to the nearby Imperial Beach Health Center for his shot after registering with recruiters. “I think (the vaccine) is an excellent idea for everyone because I know not everyone stays out of the water when they’re supposed to.”

Three years ago, San Diego State University researchers reported that hepatitis A was present in 80 percent of water samples taken off the Imperial Beach Pier.

In a 2007 survey, the nonprofit environmental group Wildcoast – a co-sponsor of Saturday’s event – found that three out of five regular ocean users in Imperial Beach reported illnesses caused by water contamination.

“Our goal is to educate the public about hepatitis A and tell them that if there are signs warning of polluted beaches, especially after rain events, they need to obey the signs,” said Paloma Aguirre, a Wildcoast program coordinator.

Imperial Beach isn’t the only coastal area that suffers from contaminated water.

“You can get hepatitis A anywhere, on any beach. Water flows,” said Dr. Daniel Johnson, a family physician at the Imperial Beach Health Center. “Imperial Beach is just being more proactive about it.”

Hepatitis A, a highly contagious liver infection caused by the hepatitis A virus, affects the liver’s functions. Although some people with hepatitis A never develop symptoms, others may feel as though they have a severe case of the flu with fever, jaundice, vomiting and stomach pain.

Hepatitis A vaccines are safe for children older than 1 as well as for most adults, including those with compromised immune systems, Johnson said. A second booster shot is needed in about six months, and that combination should provide lifetime immunity.

People who couldn’t get a free hepatitis vaccine Saturday will have more chances in the coming days. The Imperial Beach Health Center is offering free vaccines until supplies run out, thanks to a grant from the San Francisco-based Tides Foundation.

For more information, call (619) 429-3733.

Union-Tribune Staff Writer