How to Protect from Malaria

QUESTION

How can I protect my body from malaria?

ANSWER

There are a number of ways to prevent malaria. These can be placed into two categories: medication and vector protection.

For medication, there are drugs you can take to prevent the malaria parasite from developing after someone is bitten by an infected mosquito. These drugs are known as “chemoprophylaxis”.

There are several different kinds, such as doxycycline, mefloquine (marketed as Lariam), atovaquone-proguanil (marketed as Malarone) and chloroquine—the type you use depends on the type of malaria present in the area. For example, in much of Africa and India, malaria is resistant to chloroquine, so this cannot be used as a prophylactic. In parts of Thailand, resistance to mefloquine has emerged. However, if the appropriate type of prophylaxis is used, it is very effective against malaria.

The problem is that these drugs have not been tested for long-term use, can be expensive and may have side-effects. Therefore they are of limited use for people who live in areas where malaria is endemic, and are more appropriate for travelers who are in malarial areas for short amounts of time. However, anti-malarial medication may be used in a very specific way for people at particularly high-risk for malaria, such as pregnant women and young children. In these cases, the high-risk individuals receive a dose or series of doses of malaria medication in order to prevent malaria. This form of prevention is known as intermittent preventive therapy (IPT).

Vector prevention involves protecting oneself against getting bitten by mosquitoes. This can involve wearing long-sleeved clothing in the evenings and at night, when malaria mosquitoes are most active, or wearing insect repellent on exposed skin. Indoor residual spraying, whereby repellent and insecticides are sprayed inside the house, can also be used to bring down the number of mosquitoes.

Another very effective technique for preventing malaria is to sleep under a long-lasting insecticide-treated bednet. The mesh acts as a barrier against the mosquitoes, and the insecticide impregnated in the mesh further repels the mosquitoes and prevents them from biting through the mesh.

Malaria in Australia and Bali

QUESTION

Is Australia, Bali or Tasmania in the malaria affected area?

ANSWER

While malaria used to be endemic in parts of Australia (not Tasmania—it is too cold), the country was declared to be free of malaria transmission in 1981. However, several hundred cases are reported in Australia every year, mainly brought back by travellers returning from other regions, such as south-east Asia and Africa.

The tropical northern region of Australia, i.e. Northern Queensland and particularly the Torres Strait area, is climatically very suitable for malaria transmission, and some local outbreaks may occur. Similarly, Bali is climatically very suitable for malaria, and some transmission does occur, though not high levels. For both Bali and northern Australia, it is not usually considered necessary to take anti-malarial medication while visiting the region, but precautions should be taken against getting mosquito bites, as this is how malaria is transmitted. Such precautions include sleeping under an insecticide-treated bednet, wearing long-sleeved clothing in the evenings and at night, and wearing insect repellent on exposed skin.

Malaria Prevention

QUESTION

what is the prevention of malaria?

ANSWER

There are many ways in which to prevent malaria. I’ll break them down into three categories: 1) medical prevention, 2) protection from getting mosquito bites and 3) vector control.

1) Medical prevention

Malaria can be prevented using certain medications. Taking drugs to prevent a disease is known as “chemoprophylaxis”, and so these drugs are often referred to as “malaria prophylactics”. There are several different types of malaria prophylactic: the most common ones are chloroquine, a mix of atovaquone and proguanil (marketed as Malarone), mefloquine (marketed as Lariam) and doxycycline. The mode of taking these medications vary (Lariam is taken once a week, for example, whereas the others are usually taken once every day), and they also have different restrictions and side effects. Chloroquine is not effective in areas where local forms of malaria have become resistant, for example, and Lariam is not recommended for people with a history of mental instability, as it is known to cause hallucinations and otherwise impair consciousness. Here on Malaria.com, we are actually currently running a survey on side effects of malaria prophylactic drugs, so if you have ever taken medication to prevent malaria, please take the survey: Malaria Medication Side-effects Survey: Treatment and Prophylaxis

It is worth noting that these drugs have not been tested for long term use, plus they can be expensive if taken for an extended period of time. As such, they may not be appropriate for people living in endemic areas for malaria. However, medication can be useful for preventing malaria in high risk groups, even when they are living in a malaria endemic area. One example is the use of intermittent preventive treatment (IPT) for preventing malaria infection in pregnant women, infants and young children. For more information on this, please see the review article written by Dr Felicia Lester for this website: http://www.malaria.com/research/malaria-pregnancy-preventive-treatment

2) Protection from getting mosquito bites

This section links in with the more general vector control strategies, which will be discussed below. Since malaria is transmitted through the bite of infected mosquitoes, preventing mosquito bites is a very effective way of reducing malaria incidence. One of the most popular methods for personal protection, especially in areas where malaria is endemic, is through sleeping under a mosquito bednet. The mesh prevents mosquitoes from being able to fly close to the person sleeping; however, if there are holes in the net, or the person skin is pressed directly against the mesh, the mosquito may still be able to bite them. This is where insecticide-treated bednets come in – they are impregnated with mosquito repellents to stop mosquitoes from biting through the mesh or passing through holes. Newly developed long-lasting insecticide treated bednets (LLINs) are even more effective, in that they don’t require “re-dipping” to maintain the level of repellent in the fibres, and so can protect a person for several years without losing efficacy. These LLINs have been instrumental in reducing cases of severe and fatal malaria, especially among pregnant women and young children, who are often targeted by bednet distributors.

Other methods for preventing mosquito bites include wearing long-sleeved clothing and personal application of mosquito repellent, particular those containing a percentage of DEET, which is a very effective insecticide. These measures should be especially taken in the evening, early morning and at night, which is when the Anopheles mosquitoes that carry malaria are most active.

3) Vector control

Finally, malaria can be prevented from reducing numbers of mosquitoes directly. Some methods target the adult mosquitoes; one such initiative is indoor residual spraying (IRS), whereby the inside of a house is sprayed with an insecticide to kill mosquitoes. Twelve different insecticides are approved by the World Health Organisation for this purpose, though pyrethroids are among the most popular, as they can be used on a variety of surfaces, do not leave a visible stain and can also protect against other insect pests, such as bedbugs.

Other methods for vector control focus on other parts of the mosquito lifecycle. Mosquito larvae require stagnant freshwater for their development, so some projects have worked to eliminate standing water sources, such as unnecessary ditches and puddles, which reduces the amount of habitat available for mosquitoes to lay their eggs and sustain larvae. Other programmes have spread insecticides directly in stagnant water to kill the larvae, or sought to introduce fish or other aquatic organisms, such as copepods, which consume mosquito eggs and larvae. This latter biological control approach is popular because it can also supply an area with fish for local consumption, and doesn’t contaminate water sources with chemicals.