DAYTON, Ohio (AP) — Nearly one-third of Ohio’s beaches are under health advisories after tests yielded high levels of E. coli bacteria that could sicken swimmers.

In Shelby County, Lake Loramie is among the beaches under a health advisory. A complete list of the beaches is available at the state BeachGuard website, publicapps.odh.ohio.gov/BeachGuardPublic/Default.aspx

Brian Miller, of the state Division of Parks and Recreation, tells The Dayton Daily News (http://bit.ly/1GSYuCO ) officials want people to be aware of the advisories as they head to beaches for the holiday weekend.

Three out of every 10 public beaches are under advisories this week.

Miller says he can’t recall a June where he’s seen this many spikes in E. coli bacteria. He says heavy rains, stressed sewage systems and geese have all been to blame for the issue.

Children, the elderly and those with weakened immune systems are advised not to swim during an advisory.

According to the BeachGuard website, Lake Loramie has been under an advisory since June 15 because of high bacterial levels. The pollution source is unknown.