It's an interesting topic! Of the 4 strains of Malaria, Falciparum is the most dangerous and the one that kills the most people - often colloquially known as Cerebal Malaria. It doesn't recurr - it kills you or you kill it! The two that can recur are Ovale and Vivax and these tend to give fairly mild flu-like symptoms. Sadly, I know of two engineers who had these for several years and became used to the regular recurrences. The only problem was they ignored them and failed to spot a new infection that turned out to be Falciparum and by the time the severity was realised, it was too late!
I had Falciparum in 1997 and it wasn't an experience I'd wish to repeat. Interestingly, after 7 days on a drip in a semi delerious state it appeared to have been cured. A couple of weeks later on my treturn to the UK the symptoms re-appeared and I took myself down to the local A&E to report I had malaria. Of course, they had to run various blood tests to check it wasn't something else, which led to quite an uncomfortable delay. It turned out that not all the parasites had been killed.
A certain General Manager for BHL in Lagos once sent out a memo that stated the incidence of sickness due to Malaria was unacceptable and amounted to personal negligence. He was in Lagos for 7 years and never contracted it once. A couple of years later he came out on a visit in his new role, from the UK, for 2 weeks. On his return he became ill, lapsed into a coma, was on a life support machine and was read his last rites. He eventually recovered. I think the moral of the story is that at the end of the day, Malaria is like Russina roulette - whether you get it or not is all down to the luck of the draw!