DOVER, N.H. (AP) – The hot, humid summer weather is creating ripe conditions for bacteria at popular New Hampshire beaches.

Jody Connor, who monitors public beaches for the state, said his office has posted an unusually high number of advisories this summer to warn swimmers to stay away from unsafe water.

Last summer, his office posted 33 alerts at 26 public beaches. Connor said his office posted 20 alerts at 17 public beaches through July.

He predicted the state will surpass last year’s postings if the region gets more hot, humid weather.

The weather has led to abnormally high concentrations of pollution – including algae blooms, unsafe bacteria counts and a slew of swimmer’s itch rash cases.

Swimmer’s itch, also known as duck itch, is produced by a parasite ducks carry. It infects snails, which then release it into fresh and salt water. The parasite quickly multiplies in warm water fed by runoff from heavy rains, Connor said.

It irritates human skin, and the rash can last a week or more before going away.

High e. coli bacteria levels – which can cause illnesses – also have been recorded at several lakes and ponds, Connor said.

Connor said he heard complaints about swimmer’s itch during the Fourth of July weekend at Weirs Beach in Laconia and Ellacoya State Park in Gilford while swimming in Lake Winnipesaukee. Beach inspectors also have reported seeing lifeguards with the rash and lakes Winnipesaukee and Winnisquam.

Maine officials said last week that they had issued more beach closures and advisories so far this year than they had for all of last summer.

High bacteria counts last week at several southern Maine beaches were a mystery because there was no significant rainfall leading up to the high counts, as is often the case.

Connor said beaches with unsafe bacteria levels often correct themselves within a few days. Unhealthy ocean beach bacteria levels can improve with each tide.

Connor said beach inspectors strive to make people aware of unsafe water conditions, but don’t close public beaches. That decision is usually left to host communities or other state agencies.