Malaria advice!

As we start regaining some of our liberties lost due to the COVID-19 pandemic and hopefully start travelling a bit more, I thought it may be prudent to remind ourselves to not forget about one of our old foes. Fever and malaise will probably now forever be associated with a mutated corona virus, but we must not step in the trap of missing the diagnosis of malaria. Doing so remains a potential catastrophe.

I often ask my pilots, especially the ones flying in endemic areas, what measures they take to avoid this nasty parasite. Although some are quite proactive, others leave me dismayed at their laissez-faire attitude. It is not surprising I suppose, as many have spent years operating in endemic areas, where long-term chemical prophylaxis is not practical. This does not mean, however, that they have somehow become magically immune. Having spent years in these areas without issue does not mean that the risk has become less. Even people that have grown up in endemic areas and really do have a degree of natural immunity (thanks to a mechanism that is still not truly understood) will lose this immunity rather quickly once relocating to a non-endemic area.

The most common type of malaria (literally meaning bad air) in Africa is Plasmodium falciparum, which is unfortunately also by far the most dangerous. Mosquitoes will only become infected by biting an already infected individual. Therefore not all mosquitoes will be infected and not all bites will result in an infection. But if the mosquito is infected, one bite is all it takes! The newly-arrived sporozoites make their way via your bloodstream to the liver. There it multiplies before leaving the liver and then it infects your red blood cells. There is more replication in the red blood cells and the cells are destroyed in a continued process. From the bite until the parasites run amok in your circulation (and making you ill and also being detectable on a blood test) can take anywhere between 7 and 21 days. In this time, they can end up pretty much anywhere is your body. If they end up in your brain (aka cerebral malaria) your risk of dying is about 1 in 5.

The female anopheles mosquito is the culprit. She bites between dusk and dawn. Taking care between these times by using diethyltoluamide (commonly known as DEET) containing insect repellent on exposed skin as well as permethrin containing sprays on both your clothing (preferably long sleeved of course) and the bed net will go a long way in preventing bites. In contrast, passing out next to a Landy in shorts, thanks to too many tasty R&Rs, is a great way to contract malaria, even if taking your tabs.

Malaria chemoprophylaxis (aka malaria tablets) is unfortunately not a guarantee that you cannot get malaria, although it does go a long way in improving your odds. They mainly work by preventing the replication of the parasite while in the liver. Skipping the medication for a day may interrupt the suppression activity and the infection may be able to take hold. Chemoprophylaxis must therefore still be used in combination with the above-mentioned physical countermeasures.

Chemoprophylaxis does not mask the symptoms though. This is a myth. We generally have three medications that presently work, namely mefloquine (eg Larium,) doxycycline and atovaquone/proguanil (eg Malanil.) Mefloquine is contraindicated in aircrew. Doxycycline was contraindicated due to a concern about arrhythmias by the SACAA some years ago, but I have not found any recent publications to support this. A quick oversimplified answer is that doxycycline is good and cheap but a bit inconvenient and atovaquone/proguanil is expensive and convenient.

Of course no one should or would want to be on these medications for years, which makes it difficult for many contract pilots and crew that are deployed long-term. For this reason, it is not unacceptable to use the normal preventative physical countermeasures and then ensure that you have access to reputable rapid malaria testing kits and artemether/lumefantrine (Coartem.) If you suspect that you may have malaria, use a test kit daily until you have a result or have been able to consult a doctor. If the result is positive, start the treatment. But please do not see this as being adequate by itself. This only buys you time to get to proper medical care.

What else should I mention?

  • Anti-malarial products marketed as natural and containing Artemisia are not effective. It also creates drug resistance. Please avoid using it at all costs. No it isn’t better because it is ‘natural!’
  • Mosquito coils may be useful but don’t solely rely on them.
  • Malaria that keeps coming back is not falciparum and is definitely not something anyone needs to live with. It is caused by either Plasmodium ovale or vivax. You should have it treated definitively (there is specific medication that kill the hypnozoites hibernating in your liver.)
  • Don’t be the unfortunate soul that incubates malaria for 21 days, only to now find yourself in another country which may be completely oblivious to the existence of it.
  • Travel malaria (infection outside of an endemic area) is rare but does happen. It is something to keep in mind if you spend a lot of time around airports and aircraft.
  • A host of rapid tests and even blood smears in a laboratory can give false negatives. Confirmation by means of a malaria PCR test is available in many of the bigger centres throughout the continent. When in doubt, seek immediate medical care. Delaying it can be deadly.

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