Hello, I have had malaria four times in Papua New Guinea, the last time was the “brain” type – sorry don’t know the name. The other times were ‘regular’ malaria. I have been free of it for 21 years now; could it still recur in me?
Hi Jay, thanks for your question. The “brain” type you are referring to is probably Plasmodium falciparum, which is known for causing cerebral malaria in serious cases. Actually, the majority of malaria cases in PNG are caused by this parasite, even the so-called “normal” cases, which don’t get as serious as to become cerebral.
The good news about P. falciparum is that it does not have a latent stage in the body, so patients cannot get relapses. However, there is another type of malaria in PNG, called Plasmodium vivax, which is less virulent (doesn’t cause as severe symptoms), but if not treated properly, does have the ability to leave latent stages of the parasite in the liver. These liver forms can become active a long time after the initial infection; usually the maximum limit for relapse is a couple of years though (one case in Italy reported a patient with relapse after 4 years, which was considered very unusual – the citation for this paper is Mangoni et al., 2003, ‘Case report: An unusual late relapse of Plasmodium vivax malaria, in American Journal of Tropical Medicine and Hygiene, volume 68, pages 159-160), so you should be fine after 21 years being malaria-free!
In your case, unless you were diagnosed otherwise at the time, I would think you probably were infected with P. falciparum all four times, and so there is no chance of a relapse; if you’re really worried about it, you can have a malaria test to see if you still possess antibodies against malaria, which would suggest there are still parasites in your body, and might indicate P. vivax infection (there are some blood tests which can distinguish between these different types of malaria). Then, you can take a drug called primequine, which eliminates the liver stages and ensures no further relapse.