From our mosquito experts


From our mosquito experts

How is the Zika virus prevented and controlled?

The Aedes aegypti mosquito generally carries the Zika virus from an infected person to a non-infected person. People can use a number of strategies to reduce their chance of being bitten by an infected mosquito. No one strategy is perfect or completely effective. So, people should apply several chemical and non-chemical strategies to reduce their chance of being bitten.

Stopping the Eggs

According to the Pan American Health Organization (PAHO), prevention includes reducing Aedes aegypti mosquito populations and avoiding mosquito bites from these mosquitoes. To reduce mosquito populations, at least twice a week search for sources of standing water in and outside the home and remove the water.

Cover rain barrels or domestic water tanks so mosquitoes cannot get in. Get rid of garbage in and around the home, and place in closed plastic bags and containers. Look for blocked drains to remove a source of standing water.

Aedes aegypti mosquitoes tend not to travel far, normally 400 meters or less. So, managing water sources around the home can have significant benefit in terms of reducing the number of mosquitoes.

Managing the Inside of Your Home

Mosquitoes can get into the home as people go in and out through doorways, and through windows – particularly those without secure screens.

If you don’t have screens, putting up permanent or temporary screens may reduce the number of mosquitoes getting into the home. So can avoiding leaving doors open for longer than necessary.

If mosquitoes are in the home, a pesticide product labeled for indoor use against mosquitoes may be effective at killing them. Always read the label to ensure the right product is used in the correct way. These products normally can be sprayed directly onto mosquitoes.

Also, spraying all parts of the room and then leaving the room and locking it for a period of time (again following the product’s label instructions) can be effective. Always keep people and pets (including birds) out of the room and turn off and cover any aquariums while treating the room.

Be aware that instant spray products will often have a limited time effect.

In some countries, indoor spatial repellents are available (normally continuous action electrical devices and coils) and can be effective against mosquitoes. Also, bed nets can also be helpful.

Protecting Yourself Outdoors

There are several strategies you can use to limit mosquito bites outside. Aedes aegypti mosquitoes typically actively bite during the day, particularly in the early morning and at dusk. So, taking care at these times of day can be helpful.

Wear clothes that cover your legs and arms, and wear a hat. Spray or apply personal mosquito repellent to exposed areas of the skin.

Use personal repellents that the U.S. EPA or other applicable government agencies have determined to be effective at repelling mosquitoes. According to the U.S. Centers for Disease Control and Prevention (CDC), typical active ingredients in personal mosquito repellents include DEET, Picardian (also known as Icardian or KBR 3023), Para-menthane-diol, and IR3535.

Avoid putting the product in the eyes or mouths. Parents or adults apply repellents to younger children. Read and follow all use and label instructions.

Although effective at repelling mosquitoes, repellents are not completely foolproof. Always read the label to find out how to apply it properly, when to reapply (such as after swimming) and how long it is expected to be effective.

The product’s label will normally provide the percentage of active ingredient. Personal mosquito repellents with higher percentages of active ingredients will generally last longer – but the higher percentage does not mean that they will more effectively repel mosquitoes.

According to the U.S. CDC, “pregnant women and women who are breastfeeding can and should choose an EPA-registered insect repellent[…] and use it according to the product label.”

Depending on what’s available in the market, outside spatial repellents can be an additional tool at combating mosquitoes. These products come in a number of forms including aerosol sprays and passive repellent devices.

Generally, the time of day, outside wind conditions and other factors may affect the products’ effectiveness. Again, always read the label for use instructions and area of effectiveness.