Eddie Ramirez

Eddie Ramirez

In South Texas, there are three principal rodents that create problems: the house mouse, Norway rat and roof rat. They are referred to as commensal rodents, meaning they live in close contact with humans.

Not only are they annoying, but they also cause damages to homes and buildings, causing losses of billions of dollars annually. Most importantly, they harbor and transmit disease-causing pathogens to humans.

Murine typhus, bubonic plague, hantavirus, salmonellosis, trichinosis, leptospirosis, hemorrhagic fever, ricketsialpox and rat-bite fever are the diseases these commensal rodents cause. They are also responsible for transmitting diseases to livestock, poultry and pets, including brucellosis, distemper, leptospirosis, trichinosis and tuberculosis.

How do they contaminate? Through their feces and urine. Diseases from rodents can be directly or indirectly transmitted. Direct transmission occurs through breathing in dust that is contaminated with rodent urine or droppings, direct contact with rodents or their urine and droppings and bite wounds. Indirect transmission includes tick, flea and mosquito bites.

As cooler weather approaches and we turn on our heaters and fire up our fireplaces to make our homes warm and cozy, rodents are also looking to get warm. Even though they nest outdoors in the ground, they also like to nest indoors. Norway rats nest within walls, in the space between floors, in ceilings and wherever there is clutter. Roof rats nest above ground in trees, particularly untrimmed palm trees, piles of wood or debris, vine- covered fences and stacked lumber. Overgrown landscaping is also a popular nesting area.

Mice can squeeze through a hole the size of a nickel, and rats can squeeze through a hole the size of a half-dollar coin. Before the temperatures start to dip, let’s prevent these rodents from nesting close to our homes by wiping away possible nesting sites for them and by sealing up holes inside and outside our homes. All items can be found at your local hardware store, such as steel wool, caulk, lath screen, cement and hardware cloth.

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Eddie Ramirez is an environmental health inspector with the Victoria County Public Health Department.