Ask the Expert

BRITTANY CAMPBELL, PhD, BCE, Director of Technical Services, NPMA

Q Can ticks survive and reproduce indoors off a host?

A Only the brown dog tick can complete its entire lifecycle indoors and cause an infestation in a structure. The blacklegged tick has a very high moisture requirement and will only survive about one day indoors, while other tick species like the lone star tick can only survive for a few days indoors and can’t complete its lifecycle.

The brown dog tick is a common problem in dog kennels and other dog boarding facilities, but can be an issue in homes with dogs as pets. The brown dog tick is an incredibly important vector of disease to dogs and also transmits Rocky Mountain Spotted Fever, which can affect humans. It’s important to talk with customers and advise them to speak with their veterinarian for tick control on their dogs. Additionally, if they do have an infestation of brown dog ticks indoors, then advise the customer to wash and dry all bedding and focus pesticide applications to areas where pets may frequent or potential tick harborage sites, indoors and outdoors.

Q How can you exclude pests from weep holes?

A Determining which material or product to choose will depend on the pest or pest(s) that you are wishing to exclude. Weep holes serve an important purpose structurally to a building, to allow water to escape and for air to circulate into a space. For this reason, you won’t want to use anything that may limit the movement of air or water. Choosing a mesh product or other product that would allow for proper ventilation and water movement will be ideal for this situation.

Oftentimes, given that the nature of weep holes is to allow for moisture to escape a structure, it’s not uncommon for the structural integrity of the material surrounding a weep hole (like brick) to become compromised. Therefore, the areas around a weephole could become an entry point for pests and require repair first prior to excluding the weep hole. Ultimately, the issues faced from pest intrusion relating to weep holes can differ from one house to the next, so it’s important to investigate the problem and pest at hand for each situation.

Q I’ve heard mice transmit lymphocytic choriomeningitis—what is that?

A Yes, mice do transmit lymphocytic choriomeningitis, or LCM for short. LCM is a virus and according to the CDC, about 5% of house mice are infected although they show no signs of illness. Current estimates from urban areas where people were tested for LCM antibodies has found that about 2-5% of humans are or have been infected with LCM.

Humans can become infected with LCM from rodent urine, droppings, bites, saliva or by handling nesting materials. LCM causes neurological disease in humans and symptoms usually start to occur two weeks after exposure to an infected item or rodent. The early onset of symptoms are similar to many flu-like symptoms but later phases of the illness can cause meningitis, encephalitis and other inflammatory issues that can lead to fluid that may need to be drained surgically and can affect motor ability and cognitive function. Most people do survive from LCM and clear the virus from their bodies but may have long-lasting neurological problems.

If you are working regularly with rodents, it’s important to take proper precautions to prevent LCM and other rodent-transmitted diseases. Be sure you are working in an area that is well ventilated or you have proper respiratory protection. Wear gloves when handling and cleaning up rodents and infested items. Disinfect areas that have been contacted by rodents and advise customers to properly disinfect areas that have been frequented by rodents.