Zika, Mosquitoes, and Standing Water

With spring weather and mosquito season coming soon in the United States, the Zika virus – and the mosquitoes that carry the virus – may be a major concern. Zika is currently affecting more than 30 countries and territories in the Americas and Pacific Islands. Zika virus is primarily spread through the bite of an infected Aedes aegypti mosquito. People and communities can take steps to reduce the number of mosquitoes in their homes and communities to protect themselves from Zika.

How Does Water Help Mosquitoes Breed?

Aedes aegypti is known as a “container-breeding mosquito” because it likes to lay eggs in and around standing water. Studies show that female mosquitoes prefer to lay eggs in water that collects or is stored in manmade containers.

Aedes aegypti mosquitoes lay eggs on the walls of water-filled containers. Eggs stick to containers like glue and remain attached until they are scrubbed off. The eggs can survive when they dry out—up to 8 months. When it rains or water covers the eggs, they hatch and become adults in about a week.

Reduce mosquitoes at home

Here are a couple of steps you can take to prevent mosquitoes from living and breeding around your home.

Remove standing water

Keep mosquitoes from laying eggs inside and outside of your home. Items in and around people’s homes can collect water. Once a week, empty and scrub, turn over, cover, or throw out containers that hold water, such as

• Vases
• pet water bowls
• flowerpot saucers
• discarded tires
• buckets
• pool covers
• birdbaths
• trash cans, and
• rain barrels.

These actions can help reduce the number of mosquitoes around areas where people live.

Follow safe water storage tips

If water must be stored, tightly cover storage containers to prevent mosquitoes from getting inside and laying eggs.

Reduce mosquitoes in the community

Communities also can take steps to reduce the number of mosquitoes and the chances of spreading disease.

Build systems that distribute safe water

If people have access to clean and safe water in their communities, they will not need to store it in and around their homes. Research has shown that when community-wide distribution systems are built, the number of mosquitoes decreases, because water is not being stored near areas where people live.

Improve sanitation

When water is contaminated with organic matter (for example, human or animal waste, grasses, and leaves), the chances that mosquito larvae will survive may increase because contaminated matter provides food for larvae to eat. Sanitation departments and wastewater treatment plants remove organic wastes and treat water with chlorine or other disinfectants. These activities may decrease mosquito populations and, simultaneously, prevent diarrheal diseases.

*Basic sanitation includes access to facilities for the safe disposal of human waste, and the ability to maintain hygienic conditions, through services such as garbage collection, industrial/hazardous waste management, and wastewater treatment and disposal.

Water, sanitation, and hygiene* (WASH) are critical to keep people healthy and prevent the spread of many different disease, including Zika. World Water Day recognizes the importance of safe drinking water and improved sanitation and hygiene in the health of our world’s population.

Learn more about World Water Day at www.unwater.org/worldwaterday and visit www.cdc.gov/healthywater/global for more information about CDC’s efforts to ensure global access to improved water, sanitation, and hygiene.

For more information on the Zika virus, and for the latest updates, visit www.cdc.gov/zika.