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What are they?

Pests are insects and other small animals that can harm human health, damage crops and food supplies, and destroy homes and other buildings. Pests that sting or bite include ants, bed bugs, bees, fleas, flies, lice, mosquitoes, spiders, and ticks. Pests that infest food or fabric include centipedes, cockroaches, dust mites, moths, and silverfish. Wood-destroying pests include carpenter ants, termites, and wood-boring beetles. Other pests include lizards, mice, moles, rabbits, raccoons, rats, skunks, snakes, squirrels, and voles.

Why are they a concern?

Many pests can harm humans. Dust mites and cockroaches can cause allergies, asthma, and other respiratory problems. Cockroaches can carry and spread diseases, including salmonella. Fire ant stings can cause serious allergic reactions. Fleas can bite, causing allergies. Flies can carry bacteria, viruses, and several diseases. Mosquito bites can cause infections, allergies, pain, and itching.

Rats can carry and spread diseases, including:

  • Hantavirus, an often deadly respiratory disease
  • Plague, a contagious bacterial disease marked by fever and delirium
  • Rat-bite fever, a bacterial illness
  • Salmonella, a bacterial infection in the intestine that is usually caused by food poisoning

Ticks can carry and spread serious diseases such as Lyme disease and Rocky Mountain spotted fever. Wasp stings can cause pain, itching, swelling, and allergies that can even cause death.

Who is at risk?

People who are exposed to pests, whether indoors or outdoors, are at risk.

What pollutants are of greatest concern?

Mosquitoes in the United States can carry serious diseases such as:

  • Dengue fever, a viral disease marked by fever and pains in the joints
  • Encephalitis, an infection or allergy that can make the brain swell
  • West Nile virus a virus causing encephalitis and flu-like symptoms

In some other countries, mosquitoes can carry these diseases, as well as malaria, yellow fever, and Zika virus, virus that can pass from a pregnant woman to her fetus and cause birth defects (in the U.S., Puerto Rico is an area with risk of Zika).

Reduce your risk

  • Do you leave food on the kitchen counter or in pet bowls?
  • Do you have standing water or leaky pipes in your home?
  • Do you go to wooded areas where you might be exposed to ticks?
  • Do you visit areas where you might be exposed to mosquitoes?
  • Do you travel to other countries?
  • Keep all food items in sealed containers.
  • Clean kitchen and dining areas after eating.
  • Declutter your home. Recycle stacks of newspapers, magazines, or cardboard.
  • Keep a clean house. Wash bedding, and vacuum regularly to remove dust mites.
  • Prevent bed bugs by:
    • Never bringing bed frames, mattresses, box springs, or upholstered furniture found on the street into your home.
    • Checking all used or rented furniture for bed bugs.
    • Inspecting beds and furniture when you travel. Keep suitcases off the floor and the bed. Inspect suitcases before you leave.
    • Immediately washing and drying your clothes on hot settings if you have been exposed to bed bugs, or store your clothes in sealed plastic until you can wash them.
  • Fix leaky pipes and remove standing water throughout the home.
  • Fill in cracks and crevices around the house. Use steel wool to fill spaces around pipes.
  • Install screens to discourage crawling and flying pests from entering your home.
  • Remove or destroy outdoor pest hiding spots.
  • Remove breeding sites. Do not leave garbage or pet droppings outside. 
  • If you go into wooded areas, check your body for ticks.
  • Use insect repellent (read the label before applying).
  • Avoid mosquito bites while traveling to other countries:
    • Learn about country-specific health risks.
    • Wear long-sleeved shirts and long pants.
    • Use insect repellent as directed on the label.
    • Stay in places that have air conditioning or use window and door screens. If this is not possible, sleep under a mosquito bed net.
  • Follow CDC vaccination guidelines for travel to other countries.
  • Use insect repellents registered by the U.S. Environmental Protection Agency. When used correctly, they have been proven safe and effective for children, and even for pregnant and breastfeeding women.
  • Indoor allergens and irritants can trigger an asthma attack. If your child has asthma, keep your home clean and free of dust and pests. Wash sheets regularly. Use hypoallergenic covers for the mattress, box spring, and pillows. Remove rugs and carpeting wherever possible.
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