May is Lyme Disease Awareness Month, a timely reminder to take simple steps to protect yourself, your family, and your pets from tick bites. According to the Centers for Disease Control and Prevention, Lyme disease is the most common vector-borne disease in the United States. Here in Marin and Sonoma counties, ticks are a natural part of the environment, especially in wooded, brushy, and grassy areas.

At the Marin/Sonoma Mosquito and Vector Control District, staff regularly collect and test ticks from parks and public lands to better understand local risk. These ticks are tested for Borrelia burgdorferi, the bacterium that causes Lyme disease. Each year, about 2.10% to 4.08% of western black-legged ticks the District collects test positive. While the risk may seem low, prevention is still key, especially during spring and early summer when tiny, hard-to-see nymph ticks are most active.

The good news is that a few simple habits can go a long way in reducing your risk.

REPEL
Use an EPA-registered insect repellent containing DEET (at least 20%), Picaridin, IR3535, oil of lemon eucalyptus (OLE), or para-menthane-diol (PMD). You can also treat clothing and gear with permethrin. When heading into tick habitat, wear light-colored long sleeves and pants to help spot ticks more easily.

INSPECT
Check yourself, your children, and your pets for ticks during and after outdoor activities. Pay close attention to areas like behind the knees, under the arms, around the ears, and along the hairline.

REMOVE
If you find a tick, remove it as soon as possible using fine-tipped tweezers. Grasp the tick close to the skin and pull straight out. After coming indoors, place clothing in the dryer on high heat for at least 10 minutes to kill any ticks. Showering soon after being outside can wash off ticks that have not yet attached.

PROTECT YOUR PETS
Pets can bring ticks into your home, so prevention is important for them too. Talk to your veterinarian about tick prevention products such as topical treatments, collars, or oral medications. After spending time outdoors, check your pets carefully, especially around the ears, neck, between the toes, and under the collar. Keeping your yard well-maintained by trimming tall grass and brush can help reduce tick habitat.

Spending time outdoors is one of the best parts of spring. By staying aware and taking a few easy precautions, you can enjoy the season while protecting your health.

For more information about ticks and tick-bite prevention, visit www.msmosquito.org

Hantavirus in the News

A hantavirus outbreak on a cruise ship has recently received a lot of attention. Some social media posts have raised concern that this could become another worldwide health emergency.

Fortunately, the Centers for Disease Control, the World Health Organization, and the California Department of Public Health all assess the public risk as extremely low. The event appears to involve a rare set of circumstances rather than a widespread public health risk.

The hantavirus strain connected to the cruise ship cases is Andes virus. This strain is found in the southern Andes region of Argentina and Chile and has not been found in the United States. 

In California, the deer mouse is the rodent that carries Sin Nombre virus, the hantavirus of concern in our region. These mice can carry the Sin Nombre virus strain, which is found in their droppings, urine, saliva, and nesting materials.

Unlike the Sin Nombre virus (the strain found in California and across North America), Andes virus has been linked to rare cases of person-to-person spread after close, prolonged contact.

People cannot catch Sin Nombre virus from other people. Infections can happen when someone disturbs areas where rodents have been active and breathes in tiny particles from contaminated dust. This can happen while cleaning garages, sheds, cabins, storage spaces, or other buildings that have been closed for a while.

The good news is that there are easy ways to reduce your risk from hantavirus in California:

• Seal openings to keep rodents out of homes and buildings
• Open doors and windows to air out closed spaces before cleaning
• Wear gloves and a properly fitted mask when cleaning rodent-contaminated areas
• Never sweep or vacuum rodent droppings or nesting materials.
• Soak rodent urine and droppings with a bleach solution for 5 minutes (or as directed on the disinfectant product label), then wipe up with paper towels

More information regarding the Andes hantavirus and our native hantavirus (Sin Nombre) can be found by visiting the California Department of Public Health and/or the Centers for Disease Control websites.