Longitudinal Studies of Plasmodium falciparum Malaria in Pregnant Women Living in a Rural Cameroonian Village with High Perennial Transmission

Abstract

Abstract. A prospective longitudinal study of Plasmodium falciparum in pregnant women was conducted in the rural village of Ngali II, where malaria is hyperendemic and individuals receive ~0.7 infectious mosquito bites/person/day throughout the year. Pregnant women ( N = 60; 19 primigravidae, 41 multigravidae) were enrolled early in pregnancy (median 14 wk) and were followed monthly, with 38 women followed through term (5.7 ± 1.1 prenatal visits and delivery). The total number of times primigravidae were slide-positive during pregnancy was higher than multigravidae (3.3 ± 1.1 versus 1.3 ± 1.3 times; P < 0.001), but no difference in the number of polymerase chain reaction-positive cases (4.6 ± 1.7 and 3.4 ± 1.7 times, P = 0.106) or total genotypes they harbored (8.9 ± 3.2 and 7.0 ± 2.9) was found. Only 7.9% women developed symptomatic infections. All primigravidae and 38% multigravidae were placental malaria-positive at delivery ( P = 0.009). Genotyping showed that 77% of placental parasites were acquired ≥ 30 wks in pregnancy. These results help identify the extent of malaria-associated changes women experience during pregnancy.

High Levels of Antibodies to Multiple Domains and Strains of VAR2CSA Correlate with the Absence of Placental Malaria in Cameroonian Women Living in an Area of High Plasmodium falciparum Transmission

“…Women living in Ngali II are bitten, on average, every other night by a P. falciparum-infected mosquito and thus were exposed to placental isolates very early in pregnancy. Epidemiological studies show that multigravid women in Ngali II are slide positive fewer times during pregnancy and have fewer and lower-density placental infections than primigravidae (33), indicating that multigravidae have acquired significant protective immunity. The situation is different in the lower-transmission area in the city of Yaoundé, where women are exposed to ϳ1 infectious mosquito bite per month and may not become infected until the middle to end of the second trimester.…”

“…Women who became blood smear-positive for P. falciparum were provided with antimalarial drugs and iron supplements, based on the government policy for treatment of pregnant women. Initially, chloroquine was the drug of choice, but due to increasing drug resistance, artemisinin in combination with amodiaquine was adopted as the first-line malaria drug in 2004, the last year of sample collection (33). None of the women received antimalarial treatment close enough to delivery to affect their placental malaria status.…”

Influence of Intermittent Preventive Treatment on Antibodies to VAR2CSA in Pregnant Cameroonian Women

“…Details of the study have been described previously. 29 This study included 92 women, 42 of whom were followed monthly throughout pregnancy and an additional 50 women enrolled at delivery, and women in this study did not use antimalarial preventive measures. In 2008, a second prospective longitudinal study was initiated after the government policy on IPT and ITN was implemented.…”

“…Both studies took place at prenatal clinics in the rural villages of Ngali II and Ntouessong, Cameroon, where P. falciparum is perennial. 29 Between 2001 and 2004, pregnant women were enrolled during the first trimester, followed monthly until delivery, and treated for malaria if they became slide positive for malaria. Details of the study have been described previously.…”

Prevalence of malaria and soil-transmitted helminth infections and their association with undernutrition in schoolchildren residing in Mfou health district in Cameroon

“…E-mail: vtchinda1@yahoo.com Brooker et al, 2007;Brooker, 2010). In Cameroon, both infections are prevalent and responsible for increased morbidities and associated consequences in vulnerable populations, including young children, pregnant women and school-age children (Quakyi et al, 2000;Brooker et al, 2000;Kimbi et al, 2005a,b;Tchuem and N'Goran, 2009;Leke et al, 2010). Schoolchildren living in an environment with inadequate sanitation (Ziegelbauer et al, 2012), usually in deprived communities in rural areas, are likely to be infected with at least one of the three main STHs (Ascaris lumbricoides, Trichuris trichiura and hookworms [Ancylostoma duodenale and Necator americanus]), as well as other helminths species (Tchuem et al, 2003;Bethony et al, 2006;Mupfasoni et al, 2009;Ayalew et al, 2011).…”