Biomedical subjects

R W Steketee

Publications and source records attributed to R W Steketee.

76 records · Page 5Linked to original sources

PubMedDate not supplied

Antenatal chloroquine chemoprophylaxis in Malawi: chloroquine resistance, compliance, protective efficacy and cost.

The roles of Plasmodium falciparum resistance to chloroquine and compliance in the protective efficacy of the antenatal chloroquine prophylaxis programme in Malawi were evaluated by interviewing pregnant women attending antenatal clinics and examining them for P. falciparum parasites in thick smears and chloroquine metabolites in urine. 36% of 642 women had urine chloroquine metabolite levels compatible with regular compliance to the weekly chloroquine dosage schedule. Among a subgroup of 288 pregnant women who were provided weekly prophylaxis under supervision for 4 consecutive weeks, P. falciparum infection rates were 37%, representing the failure of chloroquine to eliminate P. falciparum in Malawi. Among pregnant women not taking prophylaxis, the P. falciparum infection rate was 48%. Based on the P. falciparum infection rates among these 2 groups of women, the protective efficacy of CQ chloroquine was estimated as 23%. If the 36% of pregnant women who had chloroquine in their urines accurately estimates the proportion of women who comply with the prophylaxis programme in Malawi, the actual protective efficacy of the programme would be 8%. The cost of preventing one P. falciparum infection among pregnant women in the Malawi programme is estimated at US$ 10.87. This is an unacceptably high cost in much of Africa, and research is required to define more cost-effective interventions, including more effective drugs, and health education programmes to improve compliance among pregnant women.

Animals↗

PubMedDate not supplied

In-hospital morbidity and mortality due to malaria-associated severe anaemia in two areas of Malawi with different patterns of malaria infection.

We examined the relative contribution of malaria-associated severe anaemia (parasitaemia and haematocrit < or = 15%) to malaria-related morbidity and mortality among children admitted at 2 hospitals in areas with different seasonal patterns of malaria infection in Malawi. The prevalence of malaria-associated severe anaemia was 8.5% among admissions at the hospital in an area with sustained, year-round infection (Mangochi District Hospital [MDH]), compared to 5.2% at the hospital in an area with a fluctuating pattern of infection (Queen Elizabeth Central Hospital [QECH]). Infants at MDH were nearly twice as likely to have malaria-associated severe anaemia as were those at QECH. Parasite density on admission was not related to the risk of severe anaemia at MDH, but it was at QECH. A similar proportion of all deaths was attributed to malaria at MDH (17.5%) and QECH (20.4%). However, malaria-associated severe anaemia accounted for 54% of malaria-related deaths at MDH compared to only 32% at QECH. Malaria-associated severe anaemia contributed significantly to morbidity and mortality at both sites, but its impact was more marked in the area with a sustained pattern of infection. These findings suggest that seasonal fluctuations in malaria infection may contribute to differences in patterns of malaria disease.

Age Factors↗

PubMedDate not supplied

Cost-effectiveness of sulfadoxine-pyrimethamine for the prevention of malaria-associated low birth weight.

Prevention of placental malaria through administration of antimalarial medications to pregnant women in disease-endemic areas decreases the risk of delivery of low birth weight (LBW) infants. In areas of high Plasmodium falciparum transmission, two intermittent presumptive treatment doses of sulfadoxine-pyrimethamine (SP) during the second and third trimesters of pregnancy are effective in decreasing the prevalence of placental malaria in human immunodeficiency virus (HlV)-negative women, while HIV-positive women may require a monthly SP regimen to reduce their prevalence of placental parasitemia. A decision-analysis model was used to compare the cost-effectiveness of three different presumptive SP treatment regimens with febrile case management with SP in terms of incremental cost per case LBW prevented. Factors considered included HIV seroprevalence, placental malaria prevalence, LBW incidence, the cost of SP, medical care for LBW infants, and HIV testing. For a hypothetical cohort of 10,000 pregnant women, the monthly SP regimen would always be the most effective strategy for reducing LBW associated with malaria. The two-dose SP and monthly SP regimens would prevent 172 and 229 cases of LBW, respectively, compared with the case management approach. At HIV seroprevalence rates greater than 10%, the monthly SP regimen is the least expensive strategy. At HIV seroprevalence rates less than 10%, the two-dose SP regimen would be the less expensive option. When only antenatal clinic costs are considered, the two-dose and monthly SP strategies cost US $11 and $14, respectively, well within the range considered cost effective. Presumptive treatment regimens to prevent LBW associated with malaria and the subsequent increased risk of mortality during the first year of life are effective and cost effective strategies in areas with both elevated HIV prevalence and malaria transmission rates.

Adult↗

PubMedDate not supplied

The burden of malaria in pregnancy in malaria-endemic areas.

Pregnant women in malarious areas may experience a variety of adverse consequences from malaria infection including maternal anemia, placental accumulation of parasites, low birth weight (LBW) from prematurity and intrauterine growth retardation (IUGR), fetal parasite exposure and congenital infection, and infant mortality (IM) linked to preterm-LBW and IUGR-LBW. We reviewed studies between 1985 and 2000 and summarized the malaria population attributable risk (PAR) that accounts for both the prevalence of the risk factors in the population and the magnitude of the associated risk for anemia, LBW, and IM. Consequences from anemia and human immunodeficiency virus infection in these studies were also considered. Population attributable risks were substantial: malaria was associated with anemia (PAR range = 3-15%), LBW (8-14%), preterm-LBW (8-36%), IUGR-LBW (13-70%), and IM (3-8%). Human immunodeficiency virus was associated with anemia (PAR range = 12-14%), LBW (11-38%), and direct transmission in 20-40% of newborns, with direct mortality consequences. Maternal anemia was associated with LBW (PAR range = 7-18%), and fetal anemia was associated with increased IM (PAR not available). We estimate that each year 75,000 to 200,000 infant deaths are associated with malaria infection in pregnancy. The failure to apply known effective antimalarial interventions through antenatal programs continues to contribute substantially to infant deaths globally.

Africa↗