Malaria: From endemic to non-endemic zones

For anyone trying to relocate from a malaria-endemic zone like Nigeria where malaria drugs can be purchased off the counter to a non-endemic country, let's say the United States, their first concern should be how to get treatment in case the protozoan decides to strike away from home.

Malaria is endemic in certain parts of the world because the conditions necessary for its transmission are present in these regions. For the records, Plasmodium parasites are the cause of malaria, and these protozoans are transmitted to humans through the bites of infected Anopheles mosquitoes.

The risk of malaria transmission depends on a combination of factors such as the presence of the Anopheles mosquito, the prevalence of the Plasmodium parasite, the availability of suitable breeding sites for mosquitoes, and the presence of susceptible human hosts.

Some key factors contributing to malaria's endemicity in certain parts of the world include warm temperatures, high humidity, and significant rainfall, which create ideal breeding conditions for mosquitoes. Additionally, factors such as poverty, inadequate healthcare systems, and limited access to effective malaria prevention and control measures can exacerbate the problem.

The above are the reasons malaria is particularly prevalent in sub-Saharan Africa. Other regions with high levels of malaria transmission include parts of South Asia, Southeast Asia, and Latin America.

^{Source: flickr}

Why should I be concerned since I am traveling to a non-endemic country? I know that's the next question that will be going through the mind of some of my readers. Malaria not being endemic does not necessarily mean that it does not exist in other parts of the world. It is just that the risk of transmission is significantly low since the environmental factors do not support the existence of the female anopheles mosquito, the main vector of the disease.

Okay, so, if I am malaria free and decide to relocate to a region of the world that is not endemic to malaria and has no mosquitoes, does it mean my chances of coming down with malaria are non-existence? The answer is no. The fact that you tested negative for malaria before relocating does not necessarily mean you are malaria free. After infection, the protozoan has the potential to remain in incubation ranging from a few weeks to months depending on the species. Did I forget to tell you that there are 3 species of Plasmodium that can cause malaria?

During the incubation period, there are very little to no chances of detecting the parasite. Thus, many people relocate from endemic zones to non-endemic zones while the protozoan is still in incubation.

Apart from the incubation period that usually makes Plasmodium undetectable, the parasite has the tendency to remain in the liver for a varied period of time. The Plasmodium parasite can remain undetected in the liver because it is able to evade the immune system during this stage of its life cycle.

When an infected mosquito bites a person, it injects the Plasmodium parasite into the bloodstream. The parasite then travels to the liver, where it infects liver cells called hepatocytes. The parasite multiplies inside the hepatocytes, eventually producing thousands of daughter parasites called merozoites.

During this phase of the infection, the Plasmodium parasite has developed mechanisms to evade the host's immune system. For example, it can modify the surface of the hepatocytes it infects, making them less visible to the immune system. The parasite can also produce certain molecules that inhibit the immune response.

As a result of these immune evasion mechanisms, the Plasmodium parasite is able to remain undetected in the liver, causing no symptoms or signs of infection. It is only when the merozoites are released from the liver and enter the bloodstream that the immune system is activated, and symptoms of malaria begin to appear.

In other words, it is possible to carry malaria parasites undetectable in the body from a malaria endemic zone to a non-endemic zone. Once the symptoms of malaria manifest themselves while in a non-endemic zone, there are two available options:

• Get medical attention by visiting the nearest hospital. This usually comes at a cost that may be unbearable for someone that just relocated. Except if you have appropriate health insurance.
• Treat the symptoms using an OTC malaria drug.

The sad news is that OTC malaria drugs are usually not available in countries where malaria is not endemic and where available, they usually come at cut-throat prices. Malaria drugs in malaria-endemic zones are usually heavily subsidized by the government.

In summary, if you live in a malaria-endemic zone and thinking of relocating to an area where the disease is not endemic, you may want to include OTC malaria drugs on the list of important things to take along. Otherwise, you may be setting yourself up for some heavy financial commitments.

What do you think?