Mosquito Coil or Mosquito Net? How to Protect Your Home in the Rainy Season in Nigeria and Kenya

Net first, coil second. A treated mosquito net protects you through the sleeping hours, when the Anopheles mosquito that carries malaria does most of its biting. A mosquito coil can cut bites during the evening hours before bed, when the family is awake outside the nets. No coil prevents malaria on its own.

The stakes explain why the order matters, and the latest WHO figures are in the box below. This guide explains when risk rises in each country, why a new-generation net is still the first line of defence, where a coil earns its place, what the research does and does not show, why WHO's 2025 spatial-repellent recommendation does not cover coils, and how to use a coil safely at home.

We manufacture coils, and we will still say plainly that a coil reduces bites only during the hours it burns. The same household rules apply to readers in Ghana and South Africa. For how coils work in general, see our complete guide to mosquito coils.

In this guide:

• When Malaria Risk Rises: Kenya's Short Rains and Nigeria's Rainy Season
• Mosquito Net First: Pyrethroid Resistance and Why New-Generation Nets Matter
• Where a Mosquito Coil Fits: Covering the Evening Hours Before Bed
• What the Research Says: One Strong Coil Trial, One Sobering Field Study
• WHO's 2025 Spatial Repellent Recommendation: Why Coils Are Not Covered
• Is Mosquito Coil Smoke Harmful? How to Use a Mosquito Coil Safely
• Key takeaways

Mosquitoes follow water. Standing water after heavy rain is where malaria mosquitoes breed, so the start of the rains, not the first fever in the house, is the moment to check nets and restock.

• Kenya has two rainy seasons: the long rains, roughly March to May, and the short rains, roughly October to December. The Kenya Meteorological Department publishes an outlook before each season.
• Nigeria: malaria transmission in the south runs all year, while in the north it is highly seasonal (Bakare and colleagues, PLOS One); in Nasarawa State, for example, cases peaked in September in most years of the study. The Nigerian Meteorological Agency's Seasonal Climate Prediction shows when the rains are expected to start and end in each state.

If your household receives nets from a national or state campaign, the most useful thing you can do is hang every one over a sleeping space and use it every night.

A mosquito net works because it puts a barrier between you and the mosquito for the whole night, and a treated net adds insecticide that kills or repels the mosquitoes that land on it. The weakness WHO highlights is chemistry. Standard treated nets rely on one class of insecticide, the pyrethroids, and the World Malaria Report 2025 records confirmed pyrethroid resistance in 48 of 53 reporting countries between 2020 and 2024.

Use has stalled as well: in sub-Saharan Africa, just below half (47%) of those at risk of malaria slept under an insecticide-treated net in 2024, similar to levels seen since 2015.

The response has been a rapid switch to new-generation nets: pyrethroid-PBO nets, which add a synergist to help the pyrethroid work against resistant mosquitoes, and dual-active-ingredient nets, which pair a pyrethroid with a second insecticide. In 2024 these nets made up 84% of the 168 million nets shipped to sub-Saharan Africa, up from 10% in 2019, according to the same report. What that means for your home:

1. Read the label before the price tag, and choose an insecticide-treated net, ideally a PBO or dual-active-ingredient type, over a plain untreated one.
2. Hang a net over every sleeping space, starting with children under five.
3. Tuck the edges under the mattress or sleeping mat, repair holes as soon as they appear, and follow the washing instructions on the package.
4. Use it every night of the season, not only on nights when you notice mosquitoes: the malaria mosquito bites after dark whether or not you hear it.

A net, however, does nothing for the hours before you climb into it, and that is the gap the next section is about.

Think about a typical evening in Lagos or Kisumu: dinner, homework, television, visitors on the veranda, perhaps the power going off. For several hours the whole family is awake and outside any net, and that is the gap a mosquito coil is designed to fill. A coil needs no electricity, which matters wherever supply is unreliable; it smoulders for hours from a single light; and it treats the air of a semi-open space rather than one person's skin.

Light it on the veranda, or in a living room with a door or window open, as the evening begins. Place it near where the family sits but away from babies, young children and anyone with asthma, and put it out before anyone goes to sleep, including the children who go to bed first. That is also the practical answer to how to get rid of mosquitoes at night without sleeping in smoke: the coil handles the evening, the net handles the night.

A coil is not the only evening option. Where power is reliable, a plug-in vaporizer or mat does a similar job without smoke, and we compare the two formats in mosquito coils vs electric vaporizers. The cheapest protection of all is keeping mosquitoes out: close doors and windows around dusk, fit and repair window screens, and clear standing water around the compound after each storm, from puddles and blocked drains to old containers and tyres.

On price, compare more than the pack. Whether you are checking mosquito coil prices in Kenya or in Nigeria, the useful comparison is cost per hour of burn and what is inside the coil. A registered coil with a clearly stated active ingredient and burn time is better value than a cheaper pack that tells you nothing, because a coil that barely affects mosquitoes is money spent on smoke.

For the full science of how coils repel and kill, including how far the protection reaches, see our answer to does mosquito coil kill mosquitoes. This section is the short evidence box that matters most to malaria households.

The strongest result comes from Hill and colleagues, Malaria Journal, 2014: a household randomised controlled trial in Yunnan, China. Coils containing 0.03% transfluthrin, used alone, gave 77% protection against Plasmodium falciparum malaria (95% confidence interval 50–89%).

It was one trial of one formulation, in a setting very different from Lagos or Kisumu, and it does not show that a coil can stand in for a net; a Cochrane review of the coil trials concluded: “We do not know if mosquito coils offer protection against malaria” (Maia et al., 2018).

The sobering counterweight comes from West Africa. Hogarh and colleagues, Malaria Journal, 2018, tested several commercially available coils in chambers set up like local rooms in Ghana. Mosquito mortality from the coils ranged on average between 24 and 64%, and their conclusion was blunt: “the coil yielded limited protection as a mosquito avoidance method.”

How can both be true? The Yunnan trial tested one specified, modern formulation under study conditions; the Ghana study tested a range of coils sold to households. For a Nigerian or Kenyan household the reading is straightforward: a well-made coil with a proven active ingredient can cut bites, a cheap or unlabelled one may do little, and in the best evidence available the coil was an addition to the net, never a replacement for it.

Neither study supports the claim that a coil prevents malaria by itself, so be wary of any pack or seller that says otherwise.

In August 2025 WHO made a change that is easy to misread. On 13 August 2025 it recommended spatial emanators for malaria vector control, a conditional recommendation for indoor use of prequalified products, and prequalified the first two: Mosquito Shield and Guardian, both passive transfluthrin emanators that release insecticide vapour into a room without burning.

One of the key trials was run in Busia County, Kenya, where Mosquito Shield cut first-time malaria infections in children by about a third (The Lancet, 2025).

Here is the plain statement: mosquito coils are not the products WHO recommended. The recommendation applies to prequalified emanators, used indoors, as tested. A coil smoulders rather than passively evaporating, and no coil, ours included, is a WHO-recommended malaria intervention.

What the recommendation does show is that the principle behind a good coil, putting a volatile pyrethroid such as transfluthrin into the air so that fewer mosquitoes bite, is taken seriously in malaria policy. It also shows how modest even the best-studied vapour products are: a cut of about a third in infections is a real public-health gain, but it is a layer on top of nets, testing and treatment, not a substitute for them.

So if a coil pack or a market seller promises that a coil prevents malaria or is WHO-approved, treat that as a warning sign rather than a selling point. The fair claim for a coil is fewer mosquito bites during the hours it burns. Malaria protection at home still rests on sleeping under a treated net every night and seeing a health worker promptly if anyone in the family develops a fever.

Two questions Nigerians often search about coils are whether mosquito coil smoke is harmful and what the side effects are, and the answer is that the smoke is a real exposure you should manage. A 2003 chamber study in Environmental Health Perspectives (Liu et al.) estimated that one burning coil releases as much fine particulate matter (PM2.5) as 75–137 cigarettes, and the Ghana study above found carbon monoxide, volatile organic compounds and fine particles in coil smoke.

Both findings point the same way: smoke builds up where air cannot move, so where you burn a coil matters.

To light a coil, separate the double spiral gently from the centre so it does not snap, fix it on the metal stand supplied, light the outer tip, and once it glows, blow out the flame so it smoulders rather than burns. Then follow these rules:

1. Follow the directions on the pack. Rules are set by each country's regulator, and some labels allow outdoor use only.
2. Burn it where air moves: an open veranda, or a living room with a door or window open.
3. Never burn a coil in a closed room or in a room where someone is sleeping; at night, the net does that job.
4. Keep the smoke away from babies and young children, pregnant women, anyone with asthma, COPD or heart disease, cats and pet birds. For an infant, the protection is a net over the cot, not a coil in the room.
5. Stand it on a tile, metal tray or other non-combustible surface, at least 1 m from curtains, bedding, paper and fuel, and out of reach of children and pets.
6. Put it out before you leave the room or go to sleep.
7. Buy registered coils: look for a registration number, a stated active ingredient and a burn time on the pack, because an unlabelled coil tells you nothing about what you are breathing.

Our full review of the smoke science, including who is most at risk, is in our guide to mosquito coil safety and side effects.

• Net first: sleep under an insecticide-treated net every night of the rainy season, ideally a PBO or dual-active-ingredient net, starting with children under five.
• Coil second: a registered coil can cut bites in the evening hours before bed. Burn it only where air moves, keep the smoke away from babies, pregnant women and anyone with asthma, and put it out before anyone goes to sleep.
• No coil prevents malaria on its own: if anyone in the family develops a fever, see a health worker promptly.

Importers and distributors choosing coil formulations for these markets can read about OEM and private-label mosquito coil manufacturing.