The state will put poison bait on undeveloped land near Leeward O'ahu communities because it has trapped six times as many mice in Nanakuli as it did a month ago.

Warning signs will be posted today advising residents to keep animals and children out of the area, said Greg Olmsted, program manager for the Vector Control Branch of the state Department of Health.

A month ago, 30 traps were set in Nanakuli and six mice were caught, Olmsted said. As of last week, 40 mice were caught using the same traps. If the number of trapped mice increases substantially in other areas, DOH also will bait those areas, Olmsted said.

Vector control has been monitoring the rising mouse population throughout the Leeward area, including Ma'ili, Wai'anae, Makaha, Makakilo, Kapolei, Ko Olina, 'Ewa Beach, Royal Kunia and Waikele.

Leeward residents said yesterday they were happy to hear the state is taking action by baiting before mouse populations explode.

Georgette "Jo" Jordan, a Lualualei resident and member of the Wai'anae Neighborhood Board, said rodent problems seem to occur at the beginning of every summer, particularly after a wet winter. Two years ago, she said, there were so many mice in her neighborhood that she was catching about two every day.

STEALING DOG FOOD

In the past she's had to use "mice cubes" and mousetraps to combat the problem.

"Normally when things dry up, (mice) come closer to places where they can find water — homes, wherever else," she said. "That usually does cause an increase.

"I noticed (more mice) when they started stealing the dog food. I would find it in strange places."

To ensure public safety during the treatment, the poison bait will be placed in tamper-proof locked stations that will be attached to heavy blocks or staked into the ground, Olmsted said. DOH will be out today and tomorrow baiting with Prozap Zinc Phosphide Oat Bait, he said.

Some of the rodenticide will be spread by hand in fields. The traps will be placed on private property that is within 100 feet of homes and the hand-spread bait will be used in fields more than 100 feet from residences, he said.

The poison has no antidote and if there is accidental ingestion, people should call the Poison Control Center at 222-1222 immediately and take the victim to the nearest hospital, Olmsted said.

That's why the state is "using the tamper-resistant station. It's locked, and we're putting them on blocks that can't be easily moved, or staked into the ground," he said.

It's important to kill mice when they multiply because they can carry disease and damage property with their gnawing.

"We have a concern for leptospirosis and there's a possibility the fleas may carry murine typhus," he said. "The feces from the mice can contaminate food with salmonella."

Other communities may experience problems and residents should take preventive measures, including sealing holes where mice can enter the home, clearing breeding areas like piles of leaves or old newspapers, and keeping pet food dishes clean so they don't become a food source.

TRAP WITH CAUTION

If residents are trapping mice, they should be careful about handling them as well, said Dr. Arlene Buchholz, DOH veterinarian medical officer.

Place a plastic bag over your hand to pick up the dead mouse, tie the bag in a knot and dispose of it in the trash, Buchholz said. She added that she throws the trap out with the mouse because the trap could have urine, which most likely has leptospirosis, a bacterial disease that could lead to serious organ damage.

Pets also should be kept away from the areas that are being treated, she said. The poison smells like garlic and is unlikely to attract dogs or cats, but they may be tempted to eat the dead or dying mice.

"I don't think pets would eat the bait and secondary poison is not that common, but you would want to keep your pets in," she said.

Suzanne Leonida, a Wai'anae Valley resident and also a member of the Wai'anae Neighborhood Board, said that a different rodent is more of a concern for her.

"Where I live there is an empty lot and there seems to be an increase in rats, for me, in the summer," she said. "It's mostly in areas where food is available. Or in the summer they come out more because they're thirsty.

"Just got to set traps, you know? I have dogs, quite a bit of dogs, so they take care of the problem."

Reach Eloise Aguiar at eaguiar@honoluluadvertiser.com and Loren Moreno at lmoreno@honoluluadvertiser.com.