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How to Cut Down on Mosquitoes

怎样驱蚊灭蚊

From VOA Learning English, this is the Health & Lifestyle report.

Almost everyone who spends time outdoors has experienced mosquitoes. These bloodsucking insects give itchy bites and can spread disease.

Mosquitoes can spread viruses like West Nile, Zika, dengue and malaria. A 2021 report from the World Health Organization estimated that in 2020 there were 241 million malaria cases and 627,000 malaria deaths worldwide.

But there are things people can do to cut down on mosquitoes. You can make it harder for them to reproduce. And you can protect yourself.

Jessica Damiano is a gardening expert. She writes about outdoor living for the Associated Press. In a recent story, Damiano said the best control is prevention. In that story, she gave suggestions on how to cut mosquito populations where you live.

It may seem difficult to avoid mosquitoes. Some areas of the world are densely populated with them. People who live near bodies of water mayexperience more mosquitoes. But there are several measures you can take to reduce their numbers.

Mosquitoes need less than a centimeter of water to lay eggs. A female can lay hundreds of eggs at a time. So, check your property for standing water. Water can easily collect in small containers – a child’s toy, a trash can lid, or a cooking pot.

Get rid of standing water, even if the amount seems small. Make holes in the bottoms of containers that can hold unwanted water.

Other sources of water such as in ponds and bird baths can be treated with chemicals.

Damiano suggests a bacterium called Bacillus thuringiensis israelensis or Bti for short. The bacterium is a safe and effective way to kill mosquito larvae. Several kinds of Bti are available. Each target different insects. So be sure to buy the one to target mosquitoes.

Bti also comes in several forms, including ring-shaped products called “Mosquito Dunks.” These rings float in water and offer 30 days of protection. Experts at the U.S. Centers for Disease Control and Prevention say mosquito dunks “…will not harm people, pets and other animals,” and other insects, including honeybees.

This image provided by Summit Chemical Company shows a Mosquito Dunk floating in a residential fish pond. The product's active ingredient, Bti, is a bacterium strain that kills mosquito larvae in standing water. (Summit Chemical Company via AP)

You also can make your own mosquito trap. Put a handful of straw, hay, or grass cuttings into a dark-colored container filled with water. Let it sit for one to two days. Then add one mosquito dunk.

If you have many mosquitoes, place several containers around the area. Decomposing organic matter will attract the insects. They will lay eggs on the treated water. Every 30 days, change the water and add new chemicals to stop future generations of mosquitoes.

Mosquitoes also like overgrown plants. Keep your yard organized. Do not let plants grow too tall.

Running a fan at high speed will reduce mosquito activity. It works by simply blowing the insects away. Also, every time we breathe out, carbon dioxide from our breath attracts mosquitos. A fan can help get rid of our carbon dioxide quickly.

Damiano suggests avoiding chemical poison sprays. These can threaten helpful insects. These chemicals, she warns, only control a small part of the adult mosquito population. Also, she said, insect poisons need to be used several times in a season to work effectively.

Damiano says that so-called “mosquito plants” sold as mosquito repellents contain oils or chemicals that repel mosquitoes. But the plants do not keep mosquitoes away unless those chemical compounds are released, usually by crushing the leaves. Just having such a plant around will not help.

Some studies claim that citronella and lemongrass oil may provide some protection. But Damiano thinks this has not yet been proven. They may simply hide human scent.

There are other things you can do to protect yourself. Put screens in your doors and windows or keep them closed. Wear long clothing. And cut down on time spent outdoors between the early evening and the early morning. Mosquitoes are most active during that time.

Are mosquitoes all bad?

On the hunt to kill mosquitoes, you may ask yourself if they serve some purpose. Mosquitoes are pollinators, meaning they help some plants reproduce.And they are food for some animals, especially birds and bats. Also, some fish and turtles eat mosquito larvae. But Damiano says that getting rid of mosquitoes where you live will not harm the environment.

And that’s the Health & Lifestyle report.

I’m Anna Matteo. And I'm Jill Robbins.

Jessica Damiano reported this story for The Associated Press. Anna Matteo adapted her story for VOA Learning English.

Words in This Story

itchy – adj. a feeling of wanting to scratch or rub skin because of an unpleasant feeling on it 发痒的；令人感到瘙痒的

larvae – n. a young wingless form (as a grub or caterpillar) of many insects that hatches from an egg 幼虫，幼体（larva 的复数）

decompose –v. the natural process of slowly breaking down into simpler materials （使）分解

attract –v. to cause something to come to a place 吸引

spray – n. liquid that is forced out from a container to cover a small area 喷雾液体，喷剂

repellent – n. a substance used to keep something away 驱虫剂；防水剂（或布）

screen – n. a woven material that is held together by wood or metal on the sides which is placed in windows to prevent insects from entering 纱窗，纱门

pollinator – n. an animal, often an insect, that spreads pollen from plant to plant permitting plants to produce seeds 传粉者，传粉媒介，传粉昆虫