Hookworm

QUESTION

I was in Zambia 3-4 weeks ago and had yellow fever shot and malaria pills. A week ago I got a severe headache. I suffer from migraines now and then but it wasn’t one. The headache has not passed. 4 days ago I was feeling really ill. I was extremely tired and disorientated. I am nauseated, but not all the time. Have no appetite. I generally feel ill, like something isn’t right. Exhausted and almost confused. I just don’t have a fever and haven’t had the entire time—that’s why I haven’t been to doc for tests. Is having a fever the main symptom for Malaria? I am not pregnant and am generally a very healthy person.

Not sure if I should go for tests or just wait a few more days?

ANSWER

Fever is certainly a key symptom associated with malaria, due to the way the disease progresses through the human body. However, if you were taking malaria pills, it might be that they suppressed the infection sufficiently to reduce your symptoms. I would certainly recommend having a malaria test, if just for peace of mind. If you test positive you can immediately be treated, and if you are negative and still feeling unwell, you can discuss other possibilities with your doctor. One thought might be worm infections – helminths such as hookworm, roundworm (Ascaris or Strongyloides) or whipworm are very common in Zambia and are associated with symptoms of tiredness, listlessness, headache and nausea. The tests for these diseases are usually easy to perform from either a stool sample or blood test, and treatment is likewise very straightforward, with a single dose of albendazole or mebendazole for Ascaris, whipworm and hookworm, and a series of doses for Strogyloidiasis (this parasite can be harder to get rid of, though it is still very treatable. Ivermectin is another possible drug for this helminth).

Background: Deworming is recommended by the WHO in girls and pregnant and lactating women to reduce anaemia in areas where hookworm and anaemia are common. There is conflicting evidence on the harm and the benefits of intestinal geohelminth infections on the incidence and severity of malaria, and consequently on the risks and benefits of deworming in malaria affected populations. We examined the association between geohelminths and malaria in pregnancy on the Thai-Burmese border.

Methodology: Routine antenatal care (ANC) included active detection of malaria (weekly blood smear) and anaemia (second weekly haematocrit) and systematic reporting of birth outcomes. In 1996 stool samples were collected in cross sectional surveys from women attending the ANCs. This was repeated in 2007 when malaria incidence had reduced considerably. The relationship between geohelminth infection and the progress and outcome of pregnancy was assessed.

Principal Findings: Stool sample examination (339 in 1996, 490 in 2007) detected a high prevalence of geohelminths 70% (578/829), including hookworm (42.8% (355)), A. lumbricoides (34.4% (285)) and T.trichuria (31.4% (250)) alone or in combination. A lower proportion of women (829) had mild (21.8% (181)) or severe (0.2% (2)) anaemia, or malaria 22.4% (186) (P.vivax monoinfection 53.3% (101/186)). A. lumbricoides infection was associated with a significantly decreased risk of malaria (any species) (AOR: 0.43, 95% CI: 0.23–0.84) and P.vivax malaria (AOR: 0.29, 95% CI: 0.11–0.79) whereas hookworm infection was associated with an increased risk of malaria (any species) (AOR: 1.66, 95% CI: 1.06–2.60) and anaemia (AOR: 2.41, 95% CI: 1.18–4.93). Hookworm was also associated with low birth weight (AOR: 1.81, 95% CI: 1.02–3.23).

Conclusions / Significance: A. lumbricoides and hookworm appear to have contrary associations with malaria in pregnancy.

Author Summary: Intestinal worms, particularly hookworm and whipworm, can cause anaemia, which is harmful for pregnant women. The WHO recommends deworming in pregnancy in areas where hookworm infections are frequent. Some studies indicate that coinfection with worms and malaria adversely affects pregnancy whereas other studies have shown that coinfection with worms might reduce the severity of malaria. On the Thai-Burmese border malaria in pregnancy has been an important cause of maternal death. We examined the relationship between intestinal helminth infections in pregnant women and their malaria risk in our antenatal care units. In total 70% of pregnant women had worm infections, mostly hookworm, but also roundworm and whipworm; hookworm was associated with mild anaemia although ova counts were not high. Women infected with hookworm had more malaria and their babies had a lower birth weight than women without hookworm. In contrast women with roundworm infections had the lowest rates of malaria in pregnancy. Deworming eliminates all worms. In this area it is unclear whether mass deworming would be beneficial.

Citation: Boel M, Carrara VI, Rijken M, Proux S, Nacher M, et al. (2010) Complex Interactions between Soil-Transmitted Helminths and Malaria in Pregnant Women on the Thai-Burmese Border. PLoS Negl Trop Dis 4(11): e887. doi:10.1371/journal.pntd.0000887

Editor: Simon Brooker, London School of Hygiene & Tropical Medicine, United Kingdom

Copyright: © 2010 Boel et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Funding: This study was part of the Wellcome Trust Mahidol University Oxford Tropical Medicine Research Programme funded by the Wellcome Trust of Great Britain. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing interests: The authors have declared that no competing interests exist.

More information: Full text: Complex Interactions between Soil-Transmitted Helminths and Malaria in Pregnant Women on the Thai-Burmese Border (PDF)