The epidemiology of malaria among pregnant women attending antenatal clinics in an area with intense and highly seasonal malaria transmission in northern Ghana

Objective  To describe the factors associated with malaria infection and anaemia in pregnancy in northern Ghana.
Method  We studied 3642 pregnant women of all gravidities and gestational age of 18–32 weeks who attended an antenatal clinic in the Kassena-Nankana district of Ghana between June 2004 and July 2006. Blood samples were examined for haemoglobin concentrations and parasitaemia, and we obtained socio-demographic data, an obstetric history, information on their past and current state of health and bed net use.
Results  The overall prevalence of malaria parasitaemia during pregnancy was 47%. Older age [adjusted odds ratio (AOR) 0.65, 95% CI 0.54–0.78], multigravidity (AOR 0.51, 95% CI 0.42–0.61) and third trimester of pregnancy (AOR 0.85, 95% CI 0.73–0.99) were associated with a decreased risk of parasitaemia. Enrolment during the rainy or post-rainy season was associated with an increased risk of parasitaemia (AOR 2.59, 95% CI 2.20–3.04 and AOR 3.12, 95% CI, 2.60–3.74 respectively). Malaria infection was associated with an increased risk of anaemia among young women. The prevalences of anaemia (Hb<11.0 g/dl) and severe anaemia (Hb<7.0 g/dl) during pregnancy were 72% and 2% respectively. The risk of anaemia was lower in older women (AOR 0.79, 95% CI, 0.64–0.97), multigravidae (AOR 0.67, 95% CI 0.55–0.83) and in educated women (AOR 0.81, 0.68–0.98).
Conclusion  The prevalence of malaria parasitaemia and anaemia among pregnant women in Kassena-Nankana district is high with marked seasonal variation. Targeting of interventions to the high transmission season and to paucigravidae may be appropriate in this setting.     

Malaria in pregnancy: adverse effects on haemoglobin levels and birthweight in primigravidae and multigravidae

BACKGROUND: In areas of endemic transmission, malaria in pregnancy is associated with severe maternal anaemia and low birthweight babies. The prevalence of infection is highest in primigravidae (PG), and hence control efforts are usually geared towards this high risk group. Using a sensitive measure of placental infection, we investigated the relationship between active-acute, active-chronic and past placental infection with maternal anaemia and low birthweight in women of all gravidities. METHODS: Between January 1996 and July 1997, 912 women delivering in Kilifi District Hospital, Kenya, were recruited. Haemoglobin and peripheral malaria slides were taken prior to delivery, placental biopsies and smears were taken at the time of delivery and birthweight and maternal height and weight were measured soon after birth. Information was obtained on socio-economic and educational status. The association between placental malaria, severe anaemia and low birthweight was investigated for women of different gravidities. FINDINGS: By placental histology, the prevalence of active or past malaria in all gravidities was high, ranging from 64% in PG to 30% in gravidities 5 and above. In gravidities 1-4, active malaria infection was associated with severe maternal anaemia, adjusted OR 2.21 (95% CI 1.36, 3.61). There was a significant interaction between chronic or past malaria and severe anaemia in their effects on birthweight, whereby the risk of low birthweight was very high in women with both chronic or past placental malaria and severe anaemia: OR 4.53 (1.19, 17.2) in PG; 13.5 (4.57, 40) in gravidities 2-4. INTERPRETATION: In this area of moderate malaria transmission, women of all parities have substantially increased risk of low birthweight and severe anaemia as a result of malaria infection in pregnancy. The risk of low birthweight is likely to be particularly high in areas with a high prevalence of severe anaemia.     

Influence of socioeconomic factors on the treatment and prevention of malaria in pregnant and non-pregnant adolescent girls in Nigeria.

The influence of socioeconomic factors on the treatment and prevention of malaria was investigated in 45 pregnant and a control group of 47 non-pregnant adolescent girls in the rural community of Imesi-Ile, Nigeria. The study consisted of focus group discussions and a house-to-house survey. During the survey, clinical and anthropometric measurements were taken of the girls and they were assisted in completing a prepared questionnaire which sought information on their methods of treatment and prevention of malaria. The results showed a higher incidence of malaria parasitaemia, anaemia and fever episodes in the group of pregnant adolescent girls. Both groups of girls use identical methods for the prevention of malaria but only a few pregnant girls as compared to non-pregnant girls receive modern hospital treatment for malaria. In particular, pregnant unmarried girls were less likely to receive antenatal care, to use the local health centres for the treatment of malaria and to adopt appropriate measures for the prevention of malaria. This trend was not due to aversion to hospital treatment since most people in the community prefer modern treatment of malaria to traditional or religious methods of treatment. The low utilization of hospital treatment by the pregnant girls was found to be due to perceived high cost of treatment at the health centres and to lack of privacy. We conclude that a malaria treatment service that utilizes modern methods and is both cheap and confidential will be preferred by pregnant adolescent girls in Imesi-Ile.     

Risk factors for malaria infection and anemia for pregnant women in the Sahel area of Bandiagara, Mali

Malaria infection and anemia during pregnancy are the primary causes of maternal and fetal morbidity and mortality. The aims of this study were to identify risk factors for malaria infection and to assess the relationship between malaria infection and anemia in pregnant women. Two cross-sectional surveys were conducted in September 1993 and then again in May 1994 (the end of the rainy and dry seasons respectively). A total of 235 pregnant women were randomly selected from both the rural and urban areas of Bandiagara, Mali. According to results from multivariate analysis, the risk of malaria infection was significantly higher during the rainy season (OR= 4.85, 95% CI 2.42-9.75) the first trimester of gestation (OR= 2.21, 95% CI 1.00-4.87, in younger women (OR= 2.48, 95% CI 1.19-5.16), and in women living in the rural area (2.49, 95% CI 0.99-6.27). The risk of anemia was also higher during the rainy season (OR= 1.93, 95% CI 1.10-3.39, in the rural area (OR= 3.55, 95% CI 1.46-8.62). The risk of anemia was lower during the first trimester of gestational age (OR= 0.45, 95% CI 0.22-0.92). The relationship between malaria infection and anemia also varied with season. During the rainy season, the risk for anemia was similar among malaria-infected and non-infected pregnant women. In contrast, the risk was higher among infected pregnant women during the dry season (OR= 3.43, 95% CI 1.09-10.07). In conclusion, the data suggest, that earlier gestation age, living in the rural area, and young age rather than parity are important risk factors for malaria infection in pregnant women. Further, malaria infection is strongly associated with anemia in pregnant women particularly during the dry season and is most likely the cause of anemia. Thus, control measures against malaria infection should target younger rural women in their first trimester of pregnancy.     

Risk factors for HIV infection among asymptomatic pregnant women attending an antenatal clinic in western Kenya

Our objective was to evaluate HIV prevalence and identify risk factors for HIV infection among women attending the antenatal clinic (ANC) at a large public hospital in Kisumu town, western Kenya. Between June 1996 and November 1997, in the context of a study to determine the effect of placental malaria on mother-to-child transmission of HIV in western Kenya, HIV-1 antibody testing was offered to women with a singleton uncomplicated pregnancy of > or =32 weeks' gestation attending the ANC. Women were interviewed using a structured questionnaire and had a fingerstick blood sample collected for haemoglobin (Hb), malaria smears, and HIV antibody testing. Overall HIV seroprevalence was 26.1% (743/2844) (95% confidence interval (CI): 24.5-27.7) and in bivariate evaluation was significantly associated with anaemia (Hb <11 g/dl) (risk ratio (RR) 1.8), malarial parasitaemia (RR 1.6), fever (axillary temperature > or =37.5 degrees C at screening) (RR 1.6), a history of being treated for either vaginal discharge (RR 1.5) or tuberculosis (RR 1.6), reported alcohol consumption (RR 1.6), being an unmarried multigravida (RR 2.2) or a history of the most recent child having died (RR 2.0). Poisson regression analysis for all women identified 5 significant factors independently associated with HIV seropositivity: anaemia (adjusted RR 1.7; 95% CI 1.3-2.0), malarial parasitaemia (adjusted RR 1.7; 95% CI 1.4-2.0), a history of being treated for vaginal discharge (adjusted RR 1.5; 95% CI 1.1-2.0), fever (adjusted RR 2.0; 95% CI 1.3-3.2) and reported alcohol consumption (adjusted RR 1.6; 95% CI 1.1-2.5). Multigravidae women whose most recent child had died were also more likely to be HIV seropositive (adjusted RR 1.9; 95% CI 1.7-2.8). Only 5.5% (156/2844) of the women had none of these risk factors, of whom 12% (18/156) were HIV(+). Even though the model containing the 5 identified factors fitted the data well (goodness-of-fit chi2=18.41, P=0.10), its collective capacity to predict HIV infection was poor; while 74% of the truly positive women were correctly predicted positive by the model, 52% of the truly negative women were misclassified. Among pregnant women attending the ANC in western Kenya, we were unable to identify a subgroup at risk of HIV infection using non-serological information, indicating that wherever possible universal access to voluntary HIV counselling and testing would be preferable to targeted screening.     

Socially marketed insecticide-treated nets improve malaria and anaemia in pregnancy in southern Tanzania

OBJECTIVES: To study the uptake of socially marketed insecticide-treated nets (ITNs) and their impact on malaria and anaemia in pregnancy; and to report on a discount voucher system which aimed to increase coverage in pregnancy. METHODS: A 12-month cross-sectional study of women in the second or third trimester of pregnancy. ITN use and other factors were assessed by questionnaire and a blood sample taken for malaria parasitaemia and anaemia. 'Non-users' of ITNs included both women not using any net and women using untreated nets. RESULTS: Fifty three per cent of pregnant women used ITNs. Women aged 15-19, primigravidae, unmarried women, and those with no access to cash had the lowest ITN use. Fewer ITN users were positive for malaria than ITN non-users (25 vs. 33%: P=0.06), and the protective efficacy (PE) for parasitaemia was 23% (CI 2-41). Multiparous ITN users had a twofold decrease in parasite density compared with multiparous non-ITN users (625 parasites/microl vs. 1173 parasited/microl: P=0.01). Fewer ITN users were anaemic (Hb < 11 g/dl) than ITN non-users (72 vs. 82%: P=0.01). ITNs had a PE of 12% (CI 2-21) against mild anaemia and a PE of 38% (CI 4-60) against severe anaemia (Hb < 8 g/dl). There was a trend in the prevalence of severe, mild and no anaemia, and of high density, low density and no malaria infection by ITN status. Recently treated nets were most effective at preventing malaria and anaemia (prevalence of mild anaemia was 68% compared with 82% for those without nets (P=0.002); prevalence of malaria was 22% compared with 33% for those without nets (P=0.02). Knowledge and reported use of the discount voucher system were low. Further qualitative research is ongoing. CONCLUSIONS: A modest impact of ITNs on pregnancy malaria and anaemia was shown in our high malaria transmission setting. The development of ITN programmes for malaria control should include pregnant women as a specific target group.     

Microscopic and sub-microscopic Plasmodium falciparum infection, but not inflammation caused by infection, is associated with low birth weight

Pregnancy-associated malaria is one of the leading causes of low birth weight in malaria endemic areas. In this study, 145 parturient women residing in areas endemic for Plasmodium falciparum in Lambaréné, Gabon, were recruited into the study after delivery, and the association of maternal P. falciparum infection, inflammatory response, and birth weight was studied. At delivery, 10% (15) of the mothers (12 were positive in both peripheral and placental blood smears, 1 was positive in peripheral blood only, and 2 were positive in placenta blood only) were positive for P. falciparum by microscopy and 23% (30) by real-time polymerase chain reaction (PCR). The level of C-reactive protein (CRP) was significantly elevated in microscopically P. falciparum-positive pregnant women (34 mg/L; 95% CI: 3-458) but not in those with sub-microscopic infections (6 mg/L; 95% CI: 1-40) compared with those free of P. falciparum infection (7 mg/L; 95% CI: 1-43). In a multivariate analysis, the presence of microscopic (adjusted OR = 28.6, 95% CI = 4.8-169.0) or sub-microscopic (adjusted OR = 13.2, 95% CI = 2.4-73.0) P. falciparum infection in pregnant women and age of mothers < 21 years (adjusted OR = 9.7 CI = 1.0-89.7), but not CRP levels, were independent predictors for low birth weight. This finding may have important operational implications and emphasizes the need for appropriate diagnostic methods in studies evaluating the outcome of pregnancy-associated malaria.     

Association of ABO blood group and P. falciparum malaria related outcomes: a cross-sectional study in Ethiopia

Studies elucidate conflicting results about the relationships between ABO blood groups and Plasmodium infection outcomes in humans. This study examined association between ABO blood group and Plasmodium falciparum (P. falciparum) malaria related outcomes among 1065 malaria suspected febrile patients who attended Dore Baafano Health Center, southern Ethiopia, between December, 2010 and February, 2011. Blood specimens were collected and examined for malaria using Giemsa-staining, while stool specimens were examined for helminth infections using Kato-Katz method. Haemoglobin level and blood group were determined using hemocue machine and antisera hemagglutination test, respectively. Clinical data were also collected for the patients. Among the study participants, the proportion of O, A, B and AB blood groups were 40.1%, 30.1%, 29.0% and 14.3%, respectively, and P. falciparum malaria cases in the corresponding blood groups were 14.8%, 14.0%, 13.4% and 15.7%. The odds of non-severe P. falciparum malaria were not significantly different between individuals of blood group A versus O or B versus O or AB versus O. Mean haemoglobin concentration was significantly lower in P. falciparum infected blood type A individuals compared to P. falciparum infected blood type O (β=-1.25, 95% CI=-2.31 to -0.19) or non-A (β=-1.27, 95% CI=-2.23 to -0.32) individuals. The odds of P. falciparum malaria related anaemia was about three times higher in individuals with blood type A compared to those with blood type O (adjusted OR=2.82, 95% CI=1.05-7.56) or non-A individuals (adjusted OR=2.84, 95% CI=1.15-7.01). However, mean P. falciparum density did not significantly differ among patients according to their blood groups. In conclusion, individuals with blood group A had higher risk of anaemia compared to those with O and non-A phenotypes among P. falciparum malaria patients. However, there is a need to investigate the mechanism.     

Prevalence and Risk Factors of Toxoplasmosis among Pregnant Women in Fortaleza,Northeastern Brazil

We determined the seroprevalence of Toxoplasma gondii and associated risk factors among 963 pregnant women attending an obstetric hospital in Fortaleza, Brazil. Seroprevalences of IgG and IgM against T. gondii were 68.6% (95% confidence interval [CI] = 65.6–71.6%) and 0.5% (95% CI = 0.06–1.0%), respectively. Seroprevalence of IgG was high in women less than 25 years of age (91.7%) and in low-income women (odds Ratio [OR] = 1.40, 95% CI = 1.02–1.90). Multivariate regression analysis showed that consumption of homemade water ice (adjusted OR = 1.49, 95% CI = 1.09–2.04), vegetables washed with untreated water (adjusted OR = 1.43, 95% CI = 1.05–1.94), consumption of chicken (adjusted OR = 1.49, 95% CI = 1.12–2.0), and dog ownership (adjusted OR= 1.46, 95% CI = 1.07–1.98) were factors associated with IgG seropositivity. Young women in northeastern Brazil living under poor socioeconomic conditions are at highest risk for acquiring infection with T. gondii. Oocyst contamination of water and soil must be addressed in future prevention strategies.     

An analysis of the determinants of anaemia in pregnant women in rural Malawi--a basis for action.

Haematological data are presented on 4104 pregnant women attending the antenatal-care facilities of two hospitals in a rural area in southern Malawi. In this area, malaria transmission is perennial and there is a high prevalence of HIV infection. The local women are exposed to drought and food shortages but experience high fertility rates. Mean (S.D.) haemoglobin (Hb) concentration was significantly lower in the primigravidae [8.7 (1.60 g/dl] than in the secundigravidae [9.1 (1.5) g/dl; P < 0.0001] or multigravidae [9.2 (1.5) g/dl; P < 0.0001]. Primigravidae also experienced significantly more iron deficiency and malaria than secundi- or multi-gravidae. For all parity groups, the lowest mean Hb levels were observed between 26-30 weeks' gestation. In primigravidae peak prevalence of malaria occurred between 16-20 weeks' gestation (38.6%) and peak prevalence of moderately severe anaemia (< 8 g Hb/dl) between 26-30 weeks' (35.7%). Multigravidae showed little variation in the prevalence of anaemia, iron deficiency and malaria with gestational age. Peak prevalences of malaria were observed in April, in the post-rainy season, with values of 51.4%, 56.0% and 25.3% for primi-, secundi- and multi-gravidae, respectively. Peak prevalences of iron deficiency occurred between April and May and those of moderately severe anaemia between May and June. Mean Hb was lower in adolescent primigravidae than in any other group of pregnant women [8.6 (1.5) g/dl], including the non-adolescent primigravidae [8.9 (1.6) g/dl; P = 0.008]. Other factors significantly associated with increased risk of moderately severe anaemia in primigravidae were illiteracy and poor nutritional status (i.e. body mass index < 18.5 kg/m2 and mid-upper-arm circumference < 23 cm). After forward, step-wise, regression analysis of relative risk (RR) factors and their 95% confidence intervals (CI), variables associated with an increased risk for moderately severe anaemia were iron deficiency (RR = 4.2; CI = 3.0-6.0) and malaria parasitaemia (RR = 1.9; CI = 1.3-2.7) in primigravidae, iron deficiency (RR = 4.1; CI = 2.7-6.3) and mid-upper-arm-circumference < 23 cm (RR = 1.8; CI = 1.1-3.0) in secundigravidae, and iron deficiency in multigravidae (RR = 3.1; CI = 4.3-6.9).     

Community perceptions of a mass administration of an antimalarial drug combination in The Gambia

To test the hypothesis that widespread treatment with artemisinin derivatives can reduce malaria transmission, a mass drug administration (MDA) campaign was undertaken in an area of The Gambia in 1999. Coverage of 85% of the target population was achieved, but the intervention did not reduce overall malaria transmission. We studied the perceptions, knowledge and attitudes of the community to the MDA campaign. A validated questionnaire was administered to randomly selected MDA participants (n = 90) and MDA refusers (n = 71). Individuals who believed in the importance of the MDA (adjusted OR 58.3%; 95% CI 17.4-195.8) and those who were aware that a high level of participation was needed for the MDA to be successful (adjusted OR 28.1; 95% CI 10.3-75.9) were more likely to participate. Understanding that the purpose of the MDA was to reduce malaria (adjusted OR 13.9; 95% CI 5.5-35.1) and knowledge of the fact that malaria is transmitted by mosquitoes and of the clinical signs of malaria (adjusted OR 3.4; 95% CI 3.1-9.0) were associated with participation. Individuals who discussed the MDA with other villagers (adjusted OR 5.5; 95% CI 2.2-13.5) and those who attended the sensitization meeting (adjusted OR 2.6; 95% CI 1.1-6.0) were also more likely to participate. Women were significantly more likely to participate in the MDA than men (adjusted OR 3.1; 95% CI 1.5-6.2). Individuals who refused to participate were unlikely to plan participation in future MDAs. One of the most difficult challenges in the implementation of a malaria control strategy such as an MDA is to convince villagers to participate and to make them aware that a high level of participation by the community is needed for success. We found that our sensitization meetings could be improved by giving more information on how the MDA works and finding means to generate small group discussions after the meeting.     

Haematological profiles of the people of rural southern Malawi: an overview

An integrative review of the results of two published and two unpublished studies of anaemia in children, adolescent females, pregnant women and adults living in southern Malawi is presented. Anaemia was universally present in all age-groups, with the higher prevalences in infants (100%) and adolescent primigravidae (93.8%). Nutritional deficits of iron and vitamin A were major contributory factors but chronic malarial haemolysis also significantly contributed to the anaemia. Among boys, anaemia was more common among those with glucose-6-phosphate-dehydrogenase (G6PD) deficiency than in those without this deficiency (P<0.002). This enzymopathy, which occurred in 23.5% [95% confidence interval (CI)=16.7%-30.1%] of the male and 30% (CI=17.3%-42.7%) of the female infants examined, was also associated with neonatal jaundice. The overall prevalences of the-alpha(3.7)/alphaalpha and -alpha(3.7)/-alpha(3.7) thalassaemia genotypes were estimated at 41.0% (CI=28.3%-53.7%) and 8.7% (CI=1.5%-15.9%), respectively. Haemoglobin AS was present in 18.1% (CI=12.8%-23.4%) of the infants and haemoglobin SS in 2.5% (CI=1.4%-3.6%). As the prevalence of infection with Plasmodium falciparum was significantly higher in infants with haemoglobin AS than in those with AA (21.4% v. 6.7%; P<0.001), an increased risk of early-onset moderate parasitaemias in young infants probably stimulates the development of immunity, protecting older heterozygotes from severe malarial infection. Innovative community approaches are required to break the cycle of ill health that anaemia supports in those living in rural areas of southern Malawi. Interventions in adolescent girls could be of particular importance, as they could break the cycle in both pregnant women and their infants.     

Does a routinely measured blood pressure in young adolescence accurately predict hypertension and total cardiovascular risk in young adulthood?

BACKGROUND: It is insufficiently known if routine blood pressure (BP) measurement by school doctors has added predictive value for later hypertension and cardiovascular risk. OBJECTIVE: To assess whether screening of BP in adolescence has additional predictive value to already routinely collected indicators of later hypertension and cardiovascular risk. METHODS: In the Dutch city of Utrecht, routine BPs and anthropometry were collected from school health records of 750 adolescents. In The Hague, standardized repeated BP measurements and anthropometry were available for 262 adolescents. Of both cohorts, 998 now young adults were recently re-examined. Predictors of adult hypertension, systolic blood pressure (SBP) > or = 140 mmHg and/or diastolic blood pressure (DBP) > or = 90 mmHg) and 10-year cardiovascular risk were analysed by logistic regression and area under receiver operator characteristics curve (AUC). RESULTS: A total of 167 young adults had hypertension. Single adolescent SBP and DBP predicted hypertension: odds ratio (OR) 1.04 per mmHg [95% confidence interval (CI): 1.03-1.06], OR 1.02 (1.00-1.04), respectively, but with little discriminative power. Gender, adolescent body mass index (BMI) and age combined predicted hypertension: AUC 0.71 (0.67-0.75), which slightly improved by adding SBP: AUC 0.74 (0.70-0.77); difference in AUC 0.03 (0.002-0.06). SBP exclusively predicted hypertension within men: OR 1.03 (1.01-1.04), AUC: 0.59 (0.53-0.65), and within women: OR 1.08 (1.05-1.11), AUC 0.74 (0.67-0.82). However, an adolescent BP of > or = 120 mmHg did not efficiently detect hypertensive men, while it detected 57.9% of hypertensive women. Only young adult men had meaningful 10-year cardiovascular risks, which only SBP predicted: OR risk score > 95th percentile 1.04 (1.02-1.07), AUC 0.67 (0.60-0.75). CONCLUSION: A single routine BP measurement in adolescent girls efficiently predicts young adult hypertension. In adolescent boys, BP predicts young adult 10-year cardiovascular risk.     

The effect of dual infection with HIV and malaria on pregnancy outcome in western Kenya

OBJECTIVE: To determine the effect of dual infection with HIV and malaria on birth outcomes and maternal anaemia among women delivering at a large public hospital in Kisumu, western Kenya. SUBJECTS AND METHODS: Data on obstetric and neonatal characteristics, maternal and placental parasitaemia, and postpartum haemoglobin levels were collected from women enrolled in a cohort study of the interaction between malaria and HIV during pregnancy. RESULTS: Between 1996 and 1999, data were available from 2466 singleton deliveries. The maternal HIV seroprevalence was 24.3%, and at delivery 22.0% of the women had evidence of malaria. Low birthweight, preterm delivery (PTD), intrauterine growth retardation (IUGR) and maternal anaemia (haemoglobin < 8 g/dl) occurred in 4.6, 6.7, 9.8 and 13.8% of deliveries, respectively. Maternal HIV, in the absence of malaria, was associated with a 99 g (95% CI 52-145) reduction in mean birthweight among all gravidae. Malaria was associated with both IUGR and PTD, resulting in a reduction in mean birthweight of 145 g (95% CI 82-209) among HIV-seronegative and 206 g (95% CI 115-298) among HIV-seropositive primigravidae, but not among multigravidae. Both HIV and malaria were significant risk factors for postpartum maternal anaemia, and HIV-seropositive women with malaria were twice as likely to have anaemia than HIV-seronegative women with or without malaria. CONCLUSION: Women with dual infection are at particular risk of adverse birth outcomes. In areas with a moderate or high prevalence of HIV and malaria, all pregnant women should be the focus of malaria and anaemia control efforts to improve birth outcomes.     

Reduced prevalence of Plasmodium falciparum infection and of concomitant anaemia in pregnant women with heterozygous G6PD deficiency

Glucose-6-phosphate dehydrogenase (G6PD) deficiency confers protection against malaria in children, yet its role in malaria in pregnancy is unknown. In a cross-sectional study among 529 pregnant Ghanaian women, Plasmodium falciparum infection, anaemia and G6PD genotypes were assessed. Of these, 30.4% were heterozygous and 2.6% were homozygous for G6PD deficiency. The prevalence of P. falciparum infection decreased from 66% in G6PD-normal women to 58% in heterozygotes, and to 50% in individuals with homozygous G6PD deficiency (Chi2(trend) = 4.4, P = 0.04). Multivariate analysis revealed that in multigravid women but not in primigravidae, heterozygous G6PD deficiency was associated with a reduced risk of P. falciparum infection (Odds ratio (OR), 0.6; 95% confidence interval (95% CI), [0.4-0.9]). This protection against infection was limited to the third trimenon of pregnancy. In addition, heterozygous G6PD deficiency was associated with a reduced risk of anaemia among infected multigravidae (OR, 0.5 [0.3-1.0]). Pregnancy is a period of high vulnerability to malaria. The results of this study provide evidence for protection against malaria in pregnancy caused by heterozygous G6PD deficiency. This advantage, even if confined to multigravid women, may contribute to the selection of G6PD variants in malaria-endemic regions.     

Toxoplasmosis-serological evidence and associated risk factors among pregnant women in southern Thailand

Toxoplasma gondii is an important parasite in pregnant women. This case-controlled study assessed the seroprevalence of toxoplasmosis in 640 pregnant women in southern Thailand and identified their associated risk factors. The overall seroprevalence of toxoplasmosis was 181 (28.3%). Of this, 138 (21.6%) were positive for only anti-Toxoplasma immunoglobulin G (IgG) antibody, 43 (6.7%) were positive for both IgG and IgM antibodies, and none were positive for IgM antibody. Multivariate analysis revealed that increasing age (adjusted odds ratio [OR] = 1.64, 95% confidence interval [CI] = 1.01-2.67), living outside Songkhla province (adjusted OR = 1.56, 95% CI = 1.08-2.24), parity (adjusted OR = 1.65, 95% CI = 1.01-2.68), contact with cats (adjusted OR = 1.70, 95% CI = 1.20-2.43), and drinking of unclean water (adjusted OR = 1.70, 95% CI = 1.08-2.68) were factors associated with Toxoplasma seroprevalence. On the basis of the results obtained, a health surveillance program should be initiated as a primary preventive measure for congenital toxoplasmosis and focus on educating women of the child-bearing age group to avoid contact with cats and to strictly practice personal hygiene.     

Malaria in pregnancy and its consequences for the infant in rural Malawi

Maternal malaria and anaemia, pregnancy and infant outcomes are reviewed among a cohort of mothers and their babies living in Chikwawa district, southern Malawi. Overall, 4104 women were screened at first antenatal visit and 1523 at delivery. Factors independently associated with moderately severe anaemia (MSA; < 8 g haemoglobin/dl) in primigravidae were malaria (relative risk = 1.9; 95% confidence interval = 1.6-2.3) and iron deficiency (relative risk = 4.2; 95% confidence interval = 3.5-5.0). Only iron deficiency was associated with MSA in multigravidae. After controlling for antimalarial use, parasitaemia was observed in 56.3% of the HIV-infected primigravidae and 36.5% of the non-infected (P = 0.04). The corresponding figures for multigravidae were 23.8% and 11.0%, respectively (P = 0.002). Over 33% of the infants born alive to primigravidae were of low birthweight (LBW; < 2500 g), and 23.3% of all newborns had foetal anaemia (< 12.5 g haemoglobin/dl cord blood). LBW was significantly associated in primigravidae with pre-term delivery, placental malaria and frequency of treatment with sulfadoxine-pyrimethamine (SP), and in multigravidae with pre-term delivery, adolescence, short stature and MSA. LBW was significantly reduced with a second SP treatment in primigravidae, and with iron-folate supplementation in multigravidae. Mean haemoglobin concentrations were significantly lower in the infant who had been LBW babies than in the others, and significantly associated with parity, peripheral parasitaemia at delivery and placental malaria. At 1 year post-delivery, life status was known for 364 (80.7%) of the 451 infants enrolled in the follow-up study. Independent risk factors for post-neonatal mortality were maternal HIV infection, LBW, and iron deficiency at delivery. This study identifies priorities for improving the health of pregnant women and their babies in this rural area of Malawi.     

The impact of insecticide-treated bednets on malaria and anaemia in pregnancy in Kassena-Nankana district, Ghana: a randomized controlled trial

The impact of insecticide-treated bednet use on malaria and anaemia in pregnancy was assessed, as a supplementary study, in a major WHO/TDR-supported bednet trial in northern Ghana between July 1994 and April 1995. The study area was divided into 96 clusters of compounds, with 48 clusters being randomly allocated to intervention. All pregnant women were included in the study but the focus was on primigravidae and secundigravidae. 1961 pregnant women were recruited into the study--1033 (52.7%) in the treated bednet group and 928 (47.3%) in the no net group. 1806 (92.1%) had blood taken for malaria microscopy and haemoglobin determination in the third trimester. Pregnancy outcomes were reported for 847 women. The characteristics of women in intervention and control groups were comparable. The odds ratios, with 95% confidence interval (CI), for different study endpoints were, for Plasmodium falciparum parasitaemia--0.89 (0.73, 1.08), for anaemia--0.88 (0.70, 1.09), for low birthweight (LBW)--0.87 (0.63, 1.19), indicating no benefit for treated bednet use. Effective net use by parity varied from 42% in primigravidae to 63% in multigravidae, in spite of free nets and insecticide impregnation. The main reasons for not using a net were warm weather and perceived absence of mosquito biting. Chloroquine use in pregnancy was low and comparable in both groups. Implications of findings for malaria control in pregnancy and further research are discussed.     

Anaemia during pregnancy: impact on birth outcome and infant haemoglobin level during the first 18 months of life

To determine the effect of maternal anaemia on pregnancy outcome and describe its impact on infant haemoglobin level in the first 18 months of life, we conducted a prospective study of 617 pregnant women and their children in Benin. Prevalence of maternal anaemia at delivery was 39.5%, and 61.1% of newborns were anaemic at birth. Maternal anaemia was not associated with low birth weight [OR = 1.2 (0.6-2.2)] or preterm birth [OR = 1.3 (0.7-2.4)], whereas the newborn's anaemia was related to maternal anaemia [OR = 1.8 (1.2-2.5)]. There was no association between an infant's haemoglobin level until 18 months and maternal anaemia. However, malaria attacks during follow-up, male gender and sickle cell trait were all associated with a lower infant haemoglobin level until 18 months, whereas good infant feeding practices and a polygamous family were positively associated with a higher haemoglobin level during the first 18 months of life.     

Comparison of the therapeutic efficacy of chloroquine and sulphadoxine-pyremethamine in children and pregnant women

Objective To compare the parasitological failure rates of under‐fives and pregnant women with parasitaemia treated with chloroquine (CQ) or sulphadoxine‐pyrimethamine (SP). Methods During a clinical trial of CQ, SP, amodiaquine (AQ) and SP plus AQ combination for malaria treatment in pregnant women in Ghana, a parallel study of treatment of children below 5 years of age with symptomatic malaria with CQ and SP was undertaken. Four hundred and fifty pregnant women with malaria parasitaemia and 203 children with malaria parasitaemia were randomized to receive CQ or SP. They were followed up and parasitological failure by days 14 and 28 after the start of treatment was assessed. Results Polymerase chain reaction (PCR)‐uncorrected parasitological failure rates by day 28 after the start of treatment with CQ were 58.5% (55/94), 38.5% (45/117), 31% (13/42) and 8.2% (4/49) in children, primigravidae, secundigravidae and multigravidae, respectively. For those treated with SP the rates by day 28 were 36.4% (32/88), 27.1% (29/107), 6.1% (3/49) and 3.8% (2/52) in children, primigravidae, secundigravidae and multigravidae, respectively. In both CQ and SP treatment arms, children were twice as likely to experience recrudescence as pregnant women (RR 2.1 [95% CI 1.6–2.6] P < 0.0001) by day 28 after the start of treatment. Conclusions Parasitological failure rates were significantly lower in asymptomatic pregnant women, particularly in multigravidae, compared with symptomatic children. Reliance on drug sensitivity results observed in children only to decide on antimalarial regimes for pregnant women may not be appropriate.