The first two human cases of West Nile virus in Pennsylvania this year have been detected, according to the Department of Health.

A Franklin County woman is recovering after being hospitalized from meningitis because of West Nile, and a Lancaster County woman is also recovering from West Nile fever, a milder form of the virus.

The Department of Health is urging everyone to minimize their exposure to mosquitoes because of what it called an unprecedented level of mosquitoes carrying the virus.

"We started detecting West Nile almost two months earlier than usual this year, so we were anticipating a busy season," said Tom Smith, York County's program administrator for West Nile detection program with Penn State Extension.

So far, the York County program has had 128 collections of traps with mosquitoes testing positive for West Nile Virus, Smith said.

Each collection is a trap that could contain up to one thousand mosquitoes, which are then separated by species and tested, said Smith.

So far the number of mosquitoes testing positive for West Nile virus is about the same as last year, but there are still six weeks of testing to go, Smith said. In the next six weeks the total could be nearly double that of last year, he said.

August and September are typically when human cases of the virus begin to show up, he said.

"Someone has to be sick enough to see a doctor, and the doctor has to make a diagnosis and get a blood test done," Smith said. "So there is a big delay from when the person probably had the onset when they actually got bit until they get diagnosed."

Staying safe: Cleaning up outside would eliminate most of York County's mosquito problems, Smith said.

The program has been getting a lot of calls about the Asian tiger mosquito.

"It has not tested positive for West Nile here. But since it is active in the daytime, it is a major nuisance," said Smith. "That specifically goes back to any kind of container where water can collect."

Since one Asian tiger mosquito was first detected in York City in 2002, the species has spread to 18 more municipalities, as it lays its eggs in containers and things like corrugated piping, said Smith.

"The biggest issue right now is all of the containers, trash and yard clutter people have that produces mosquitoes," Smith said. "You put that in combination with the heat, and the mosquitoes go from egg to adult in seven days."

Statewide sampling also shows higher numbers of West Nile virus-infected mosquitoes than any summer since monitoring began in 2002, according to the Department of Health.

-- Reach Chelsea at 505-5432 or cshank@yorkdispatch.com

Tips to prevent mosquito breeding

Simple steps to eliminate standing water around the home include:

---Remove tin cans, plastic containers, ceramic pots, discarded tires or any object that could collect standing water. Drill holes in the bottom of recycling containers left outdoors.

---Have roof gutters cleaned every year, particularly if the leaves from nearby trees have a tendency to clog the drains.

---Turn over plastic wading pools and wheelbarrows when not in use.

---Do not let water stagnate in birdbaths.

---Aerate ornamental pools or stock them with fish.

---Clean and chlorinate swimming pools, and remove standing water from pool covers.

---Use landscaping to eliminate standing water that collects on your property.

---Treat standing water that cannot be eliminated with Bti products, which are sold at outdoor supply, home improvement and other stores. Bti is a natural product that kills mosquito larvae but is safe for people, pets, aquatic life and plants.

Source: Pennsylvania Department of Health