Malaria Fever and Recovery

QUESTION

My 21 year old daughter spent 4 months on a study abroad program in Dakar. A week before returning home she started having night fevers and would complain of retrosternal pain and rib and neck and shoulder pain. The next day she would be fine.

The episodes came every other day and eventually it occurred to her that it might be malaria. It was evening so she went to a pharmacy for a rapid diagnostic test which they didn’t have but they felt she had malaria based on her symptoms and gave her a 3 day course of artesunate-mefloquine.

She returned to the United States and a day after taking her last dose, she was seen by a physician and tests were done which showed that she had contracted Plasmodium falciparum malaria. Other than the smears, all her lab tests and CXR were normal and there were no abnormal findings on physical exam, in fact she was the picture of health.

We were told that she was cured and that no follow up was necessary and that she could continue with her planned trip to Thailand the next day. About 6 hours before boarding the plane to Bangkok she developed fever of 100.9 but had absolutely no other symptoms or pain. About an hour later she had a bout of diarrhea. She had one more low grade fever on the flight (99.8). I spoke to another physician who seems more familiar with malaria and was told that she is not actually cured and may continue to have episodic fevers and symptoms for a while or it’s possible she was just suffering from an ordinary garden variety gastrointestinal bug.

I have many questions. I understand that her malaria is the most virulent type. How is it that all her lab work and physical exam is normal 1 day after completing treatment? Can we expect it to remain normal? What causes the episodic fevers if she is supposedly cured? She is on doxycycline again prophylactically (which she was on in Senegal) while in Thailand. Should she be on something else since she did contract malaria on doxycycline? (She took it religiously). Thanks for any advice. She will be seeing a physician in Bangkok ASAP, but since I won’t be there to ask questions, I am hoping you can give me some answers. Your site is the best information I have found on malaria.

ANSWER

Many thanks for the comprehensive information you have provided regarding your daughter’s condition. Even though your daughter did have the most virulent form of malaria, she was very smart to seek treatment relatively promptly, and lucky to receive appropriate medication (artemisinin-based combination therapies, such as artesunate-mefloquine, are recommended by the World Health Organization as first-line treatment against malaria). It is likely due to this prompt and effective action that her lab tests and blood parameters were all normal so soon after treatment; had she waited longer for treatment, the consequences could have been much more severe. No resistance to this medication has been detected in Africa as of yet, so she should be fully cured and thus her health should remain stable; a blood smear, where her blood is examined under a microscope, can determine this; this is a very standard procedure so could easily be carried out in Thailand if she wants.

Fever is a side effect of the body’s immune system responding to a disease threat, so it is not uncommon for some symptoms to carry on after treatment. In addition, mild side effects of anti-malarial medication can often mimic the symptoms of malaria itself, including fever and nausea.

Given also the (entirely reasonable) possibility of an additional, unrelated stomach bug, I suspect that your daughter has successfully beaten off this malaria attack, and while she should remain vigilant if similar symptoms arise again, her health in the future should not be adversely affected at all by this episode.

Also, as mentioned briefly above, medical professionals in Thailand should be well equipped to diagnose and treat malaria if she suspects she has been reinfected. It is worth noting that malaria in south-east Asia has shown signs of resistance to mefloquine (as well as other drugs, such as chloroquine and sulfadoxine-pyrimethamine), so if she does require treatment while there, she should make sure the medication they provide does not contain any of the afore-mentioned compounds.

Regarding doxycycline, it’s great that your daughter took it religiously—that is certainly the first step towards protection. Randomized placebo controlled trials have shown it is between 92-96% effective in preventing P. falciparum malaria, which is very good, but obviously not 100% perfect – even when taken perfectly, some infections do occur. In addition, there is some data which suggests that dairy products, taken together with doxycycline, may limit  the uptake of the drug. This is rarely communicated to patients, who are instead contrarily told sometimes that taking the pills together with dairy products can reduce side effects! As such, please let your daughter know that she should avoid dairy products for 2-3 hours around the time she takes her doxycycline.