Health Tips

Can malaria be prevented?

Malaria, an infection caused by a parasite--Plasmodium, that commonly infects a certain type of mosquito which feeds on humans, name Anopheles mosquitoes. Malaria occurs mainly in tropical countries, including Malaysia, especially in Sabah and Sarawak.

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Usually, people get malaria by being bitten by an infective female Anopheles mosquito. Only Anopheles mosquitoes can transmit malaria and they must have been infected through a previous blood meal taken from an infected person. When a mosquito bites an infected person, a small amount of blood is taken in which contains microscopic malaria parasites. About 1 week later, when the mosquito takes its next blood meal, these parasites mix with the mosquito’s saliva and are injected into the person being bitten.

Because the malaria parasite is found in red blood cells of an infected person, malaria can also be transmitted through blood transfusion, organ transplant, or the shared use of needles or syringes contaminated with blood. Malaria may also be transmitted from a mother to her unborn infant before or during delivery (“congenital” malaria).

The World Health Organization (WHO) reported 241 million cases and 627 thousand deaths from malaria in 2020, this is an increase from 227 million cases and 558 thousand deaths recorded in 2019. The increase in cases and deaths is due to the interruption of services due to the COVID-19 pandemic.

Why is malaria more common in tropical countries?

Generally, in warmer regions closer to the equator, malaria transmission is year-round and will be more intense. This is because in the tropical and subtropical areas, Anopheles mosquitoes can survive and multiply, and Malaria parasites can complete their growth cycle in the mosquitoes.

In many malaria-endemic countries, transmission does not occur in all parts of the country. Even within tropical and subtropical areas, the transmission will not occur

• At very high altitudes

• During colder seasons in some areas

• In deserts (excluding the oases) 

• In some countries where transmission has been interrupted through successful control/elimination programs

Symptoms of malaria 

Malaria can be mild or severe, depending on the types of parasite--Plasmodium species infected. There are 4 types of parasites that cause malaria, namely P. falciparum, P. vivax, P. ovale, and P. malariae. Infection with P. falciparum is the most severe form of malaria and can be life-threatening. 

Common symptoms include:

• Fever

• Chills

• Sweating

• Headaches

• Body aches

• Tiredness 

• Cough

• Skin that looks yellow 

• Stomach problems (loss of appetite, diarrhea, nausea, and vomiting as well as stomach pain)

Severe malaria can cause symptoms like:

• Confusion

• Seizures

• Seeing or hearing things that are not there

• Dark or bloody urine

Go to the hospital if you experience symptoms like these especially if you just returned from other tropical countries.

Pregnant women are in danger

Pregnant women have a higher risk of getting malaria than other people, and they can get much sicker. Malaria can cause the following problems:

• A miscarriage – This is when a pregnancy ends spontaneously before it reaches 20th week.

• A baby that is born too small, too early, or infected with malaria.

• Death of the mother or baby – The baby could die before or after birth.

If possible, pregnant women should avoid areas where malaria is common until about 2 months after the baby is born.

How is malaria treated?

Doctors give medicines to get rid of the parasite that causes malaria. There are several different medicines. Some people need to take more than one.

Most people can take pills by mouth, but people with severe malaria need treatment in the hospital. After initiating the treatment, you will have blood tests every day for a couple of days to see the response of the medication on the parasites. The test is basically done by examining the drop of the blood under the microscope, looking for the presence of parasites and to make sure the medicine is working. If the treatment is found ineffective or suboptimal, the doctor can give an alternative medication.

Malaria prevention

As a matter of fact, the risk of acquiring malaria differs substantially from region to region and from traveler to traveler, even within a single country as it depends on several factors such as transmission intensity, duration of stay in the endemic area, and the efficacy of preventive measures. 

Since malaria is caused by mosquito bites, hence, malaria prevention starts with mosquito bites protection, this includes several mosquito preventive measures and chemoprophylaxis, in this case, taking antimalarial medication before traveling. 

Mosquito preventive measures 

1. Insect repellent 

• Diethyltoluamide (DEET) 20-50% repellent is available in lotions, spray, or roll-on formulations. 

• It is safe and effective when applied to the skin of adults and children. Although DEET  may be used in children above 2 months, it should be used with caution as children may be at increased risk for toxicity due to greater skin absorption. 

• Low-concentration products should be used and applied sparingly. No antimalarial drug is 100% protective and must be combined with the use of personal protective measures.

2. Wearing long sleeve tops and long pants

3. Stay indoor at night 

4. Sleep in a building with good screens over the windows and doors or in air conditioned room. Or, you can sleep under a bed net treated with bug spray.

Chemoprophylaxis (the administration of a medication for the purpose of preventing disease or infection)

There are two types of chemoprophylaxis: 

1. Suppressive prophylaxis 

Suppressive prophylaxis means that they are only effective at killing the malaria parasite once it has entered the blood stage of its life cycle (where symptoms start showing up), and therefore has no effect until the liver stage is complete (parasites are ready to enter into the blood). That is why these prophylactics must continue to be taken for 4 weeks after leaving the area of risk. 

2. Causal prophylaxis 

Causal prophylactics target not only the blood stages of malaria but the initial liver stage (where parasites replicate) as well. This means that the user can stop taking the drug 7 days after leaving the risk area. 

There are different medications indicated for different types of prophylaxis.

If you travel to an area where malaria is common, taking medicine can help keep you from getting it. Discuss with your doctors if you can and get medications prescribed if you needed. Take it exactly as the doctor instructs you to, or it might not work.

All in all

Malaria can be prevented if you follow the preventive measures, and take chemoprophylaxis as instructed. Pregnant women are advised not to travel to areas where malaria is common. All travelers should seek medical attention in the event of fever during or after their return from travel to areas with high prevalence of malaria.

#WorldMalariaDay2022

DOC2US doctors are ready to provide travel health care remotely via telemedicine.

Medically reviewed by Ashwini Nair, MB BCh BAO.

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References:

1. WHO Guidelines for malaria, 13 July 2021. Geneva: World Health Organization; 2021. https://cdn.who.int/media/docs/default-source/malaria/who-ucn-gmp-2021.01-eng.pdf?sfvrsn=bd30cd9b_10&download=true ] 

2. World Health Organization. World malaria report 2021. https://www.who.int/teams/global-malaria-programme/reports/world-malaria-report-2021

3. Prevention CC for DC and. CDC - Malaria - About Malaria - Where Malaria Occurs. Published April 9, 2020. Accessed April 21, 2022. https://www.cdc.gov/malaria/about/distribution.html

4. Patient education: Malaria (The Basics) - UpToDate. Accessed April 21, 2022. https://www.uptodate.com/contents/malaria-the-basics?search=malaria%20patient%20education&source=search_result&selectedTitle=1~150&usage_type=default&display_rank=1 

5. CPG Guidelines Management of Malaria in Malaysia 2013

Written By

DOC2US Editorial Team

Reviewed By

Doc2us Medical Board