A comparative study of malaria parasite prevalence in pregnant women in hyperendemic and mesoendemic areas of Kenya

Abstract

A study was conducted in Machakos and Kwale Districts (where malaria is mesoendemic and hyperendemic respectively), to examine malaria parasite prevalence rates and parasite densities in pregnant women/ the main goal was to examine malaria parasite prevalence rates and parasite densities in relation to different age groups, parity status and gestation period of the pregnant women. The results would be helpful to clinicians in management of malaria during pregnancy at different levels of malaria endemicity. The study was carried out between February and December, 1995.

Pregnant women visiting pre natal clinics in the two areas were examined for malaria parasites. A thin and thick blood smear were taken for malaria parasite examination. Haemoglobin level, auxiliary body temperature, parity and gestation period were also determined.

Overall, the malaria parasite prevalence rate in Kwale district hyperendemic was higher than that of Machakos district mesoendemic (23.6% vs. 3.6%), (P < 0.0001).

In Kwale district, malaria parasite prevalence rate per age group significantly different (P<0.001), with the age group 15-19 years having the highest prevalence rate (37.0%). In Machakos, prevalence rate per age group was not significantly different (P>0.05).

In relation to the parity status, the malaria parasite prevalence rate was also significantly different in Kwale district (P<0.001) with the primigravida (no previous pregnancy) having the highest prevalence (36.3%), whereas in Machakos, the malaria prevalence rate did not vary with the parity status of pregnant women (P>0.05).

In both study areas malaria prevalence rate varied significantly with the gestation period (P<0.001). In Kwale, pregnant women in their 20-24 weeks of gestation had the highest prevalence rate (30.8%) whereas in Machakos, malaria parasite prevalence was highest (40.0%) in pregnant women with less than 15 weeks of gestation period.

Malaria parasite density varied significantly with age in Kwale (P<0.001), with the age group 1 (15-19 yrs) having the highest parasites densities. In Machakos, malaria parasite density did not vary with the age group (P>0.05).

Similarly, the malaria parasite densities varied with parity in Kwale district, with the primigravida having the highest densities (P<0.001) whereas in Machakos, the parasite densities did not vary with the parity status (P>0.05).

In relation to the gestation period, the malaria parasite densities did not vary significantly in both study groups (P>0.05).

The results of this study showed that malaria parasite prevalence rate and the parasite density varies significantly with age and parity status in a hyperendemic but not in mesoendemic area. Similarly, the malaria parasite groups (p<0.001) but not their parasite densities (p>0.05).

Pregnant women aged between 15-19 yrs and the primigavidas are more at risk of malaria infection in a hyperendemic area while all pregnant women regardless of age and parity in mesoendemic areas are at risk of malaria infection. These groups require more attention when infected with malaria parasite during pregnancy.