Over 40% of the world’s population or close to 3.5 billion people are live in a malaria risk area. However, many people who live in malaria hotspots can exhibit a partial immunity to malaria. While they may seem lucky, this immunity is not due to luck, but due to frequent exposure to the parasites. People who have partial immunity to malaria can still be infected but are often protected from severe courses of the disease.

It's important to remember that this partial immunity can be lost, so travelers and migrants returning to high malaria-risk locations after living abroad may no longer show that protection. So, if you fall into one of these categories, you must know how to protect yourself.

About Malaria

Malaria  is spread through infected mosquitoes, and it is most common in tropical countries because mosquitoes prefer humid and warm environments.
The disease can be life-threatening. Symptoms in those who contract malaria range from mild symptoms such as fever or headache to more severe symptoms such as seizures or trouble breathing.

Knowing how severe malaria can be, it’s important to properly protect yourself from contracting the infection, especially when traveling to a location where malaria is common. Children under five years of age, pregnant women, and immunocompromised people are particularly susceptible to a more severe course of the disease.

One of the best ways to prevent a malaria infection is to avoid mosquito bites by wearing long light-colored clothing, using bug spray, sleeping under mosquito nets and taking prophylactic medication. However, what about the people live in risk areas; how can they prevent mosquito bites throughout their lives?

Sufficiently preventing mosquito bites in life-long residents is nearly impossible, but some good can come from frequent exposure to the malaria parasite— naturally acquired immunity.

What Is Naturally Acquired Immunity to Malaria?

While malaria is responsible for more than 600,000 deaths worldwide each year, this number corresponds to only a small fraction of the 200 million cases malaria infections seen each year. Hence, the case fatality of malaria is low, but the burden of the disease, i.e. how many people become infected or get sick each year is much higher.

Many individuals with malaria do not display any symptoms (between 40-70% of cases). The reason why so many individuals living in high transmission areas have no symptoms is because their bodies have built up a partial immunity to the malaria parasites over time, something called naturally acquired immunity.

Naturally acquired immunity to malaria is most often established after children are between 4 and 6 months of age. At this time the antibodies received from their mothers begin to fade, making them more vulnerable to the infection. From this point on, each bite from an infected mosquito serves to increase their antibodies against malaria and continue building their tolerance.

However, research suggests that even numerous malarial infections do not prevent locals from ever becoming infected—those with naturally acquired immunity can experience repeat infections during their lives; they’re just less likely to produce symptoms or become severely ill.

But, if you used to live in an area with relevant malaria transmission in the past and return to visit years later, you no longer can count on this natural protection against severe malaria infection. Therefore, you need to be vigilant regarding your protection.

Traveling To a Malaria Hotspot? Arrive Prepared

If you’re planning on traveling to an area where malaria is common, it’s best to prepare yourself in advance. Avoid mosquito bites by wearing long clothing, using bug spray, sleeping under mosquito nets and taking the prophylactic malaria drugs, if that is recommended by your doctor.

Not sure if you need to worry about malaria during your upcoming travel? Book a travel consultation with us, and we can help you review what steps to take to be a healthy traveler, no matter where you’re going.

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