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R W Steketee

Publications and source records attributed to R W Steketee.

At least 55 records · Page 3Linked to original sources

Infant and second-year mortality in rural Malawi: causes and descriptive epidemiology.

Community information based on causes and circumstances of death in infants and young children in Malawi was obtained in a prospective cohort of babies delivered to women enrolled in a malaria-prevention-in-pregnancy study. Vital status information was obtained through home visits every two months; for children who died, questions were asked concerning age and date of death, symptoms preceding death, care sought, location of death (home versus facility), and duration of illness. Of 3,274 liveborn singleton infants, 181, 397, and 152 deaths occurred in the neonatal, postneonatal, and second year of life, respectively. For neonates, proportionate mortality was greatest for sepsis/tetanus (16.7%) and fever (8.6%); however, for more than half of neonatal deaths evaluated the cause was not identified. Up to 30% of neonatal deaths may have been related to prematurity. In the postneonatal period, gastrointestinal illness (39.6%), fever (18.3%), and respiratory illness (14.7%) were the leading causes. Most postneonatal illnesses lasted 1 week or less. Two-thirds of postneonatal deaths occurred outside of a health care facility, although 80% were brought to a facility for care during their illness. Infectious disease syndromes continued to be important in the second year of life, with gastrointestinal (31.6%), fever (23.5%), and measles (20.6%) the most commonly reported causes of death. In this area of rural sub-Saharan Africa, neonatal mortality contributes substantially to infant mortality, and prematurity is considered to be an important component of early neonatal deaths; infectious disease syndromes predominate in the postneonatal and second year of life. Strategies to reduce infant deaths in sub-Saharan Africa must consider these factors, as well as the observations that most children who died had brief illnesses, were taken to a health care facility before death, yet died at home.

Age Factors↗

Objectives and methodology in a study of malaria treatment and prevention in pregnancy in rural Malawi: The Mangochi Malaria Research Project.

Malaria infection due to Plasmodium falciparum has been widely recognized as associated with important adverse consequences in pregnant women, particularly in areas of high transmission. Although strategies using antimalarial drugs for prevention had been recommended, even by the late 1980s, few studies had been carried out to examine the efficacy of these prevention efforts. The objectives of the Mangochi Malaria Research Project investigation were to determine the comparative efficacy of regimens containing chloroquine (CQ) or mefloquine (MQ) antimalarial treatment and chemoprophylaxis in an area of CQ-resistant P. falciparum on the following outcomes: 1) the frequency of placental malaria infection; 2) the frequency of low birth weight; 3) the frequency of prematurity or intrauterine growth retardation; 4) the frequency of maternal fever illness and severe anemia; and 5) the likelihood of infant acquisition of malaria infection. Although the investigation was not designed to evaluate the role of antimalarial chemoprophylaxis and treatment on infant mortality reduction, because babies born to study women were scheduled to be followed for up to two years of life, the study allowed for an examination of mortality and morbidity in this population. The sample size was insufficient to provide more than descriptive analysis of mortality and morbidity in the fetal, perinatal, neonatal, postneonatal, and infant time intervals. The study design allowed for the evaluation of two additional aspects of maternal and infant health: other determinants of the above-listed outcomes in addition to malaria prevention (e.g., maternal age, gravidity, socioeconomic status, infection with human immunodeficiency virus or syphilis) and reported cause-specific mortality in the fetal-to-infant intervals. The study design included 22 months of enrollment of pregnant women at their first antenatal clinic visit from four clinic sites in Mangochi District, Malawi, with assignment to one of four antimalarial regimens and prospective follow-up through pregnancy, at delivery, and during infancy. All drug dosing was performed under supervision by the study team, making this an evaluation of intervention efficacy (excluding the role of patient compliance).

Antimalarials↗

Rates and risk factors for mortality during the first two years of life in rural Malawi.

Developing nations in sub-Saharan Africa experience childhood mortality rates that are much higher than any other region of the world. In a rural Malawian community we investigated risk factors for deaths occurring during the neonatal (birth-28 days), postneonatal (29-365 days), infant (birth-365 days), and second-year (366-730 days) periods among a cohort of 3,724 infants monitored from birth. The neonatal mortality rate in this cohort was 48.6 per 1,000 live births (LB); the postneonatal mortality rate was 108.7/1,000 LB. The overall infant mortality rate was 157.3 deaths/1,000 LB and the mortality rate for the first two years of life was 223.7 deaths/1,000 LB. The predominate risk factors for neonatal deaths identified in multivariate analysis were low (hazard ratio [HR] = 2.3) and very low birth weight (HR = 12.7), first pregnancy (HR = 1.8) and maternal syphilis infection (HR = 2.4). Maternal infection with human immunodeficiency virus (HIV) (HR = 1.5) predominated for postneonatal deaths. Low (HR = 1.4) and very low (HR = 5.0) birth weight, first pregnancy (HR = 1.6), maternal HIV infection (HR = 2.4), and the combination of low education and low socioeconomic status (SES) of the mother (HR = 2.0) were the most important factors during the infant period. Maternal HIV infection (HR = 3.3) and the combination of low education and low SES of the mother (HR = 2.6) were the predominate risk factors for mortality occurring during the second year. Factors that were significant in univariate analysis but not significant in the final multivariate models included prematurity, previous adverse reproductive outcome, dying during high malaria transmission season, and being born at home. Interventions to prevent maternal HIV infection and low birth weight and treatment of syphilis infection would have a great impact on reducing early childhood deaths. Improving the delivery of health care and education to women during their first pregnancy and to the most socially disadvantaged women may also help reduce the burden of early childhood mortality in communities such as the one studied in Malawi.

Cohort Studies↗

Evaluation of maternal practices, efficacy, and cost-effectiveness of alternative antimalarial regimens for use in pregnancy: chloroquine and sulfadoxine-pyrimethamine.

With the knowledge that an efficacious antimalarial administered to pregnant women would markedly reduce placental malaria and its associated risk of low birth weight (LBW), investigations were conducted to identify an antimalarial regimen practical for nationwide implementation through the antenatal clinic (ANC) system. Maternal practices, including ANC utilization and malaria treatment and prevention during pregnancy were evaluated as part of a national malaria knowledge, attitudes, and practices survey. A second study was conducted to evaluate the efficacy and cost of selected alternative antimalarial regimens. Women in their first or second pregnancy were placed on chloroquine (CQ) treatment (25 mg/kg) followed by weekly CQ (300 mg) (CQ/CQ); sulfadoxine-pyrimethamine (SP) treatment followed by CQ (300 mg weekly) (SP/CQ); or SP treatment during the second trimester and repeated at the beginning of the third trimester (SP/SP). With 87% of women attending ANC two or more times during pregnancy, most pregnant women in Malawi could be reached with an antimalarial intervention. Among 159 women in their first or second pregnancy receiving CQ/CQ, SP/CQ, and SP/SP, placental malaria parasitemia rates were 32%, 26%, and 9%, respectively (P = 0.006, by chi-square test). The SP/SP regimen was also markedly more cost-effective in preventing infant deaths, costing $75 per infant death prevented, compared with $481 for SP/CQ and $542 for CQ/CQ. These investigations suggest that a regimen consisting of two treatment doses of SP during pregnancy is an efficacious and cost-effective intervention to prevent placental malaria, and LBW-associated mortality, that can be delivered to pregnant women through ANCs in settings similar to those found in rural Malawi.

Antimalarials↗

Developing effective strategies for malaria prevention programs for pregnant African women.

The control of malaria in pregnant African women, one of several child survival strategies applied through antenatal care, has been particularly challenging. Prevention and control recommendations for typical areas of high Plasmodium falciparum transmission have promoted the use of antimalarial chemoprophylaxis to prevent placental infection. Persistently low program coverage coupled with diminishing intervention effectiveness have forced a re-evaluation of the relative importance of malaria in pregnancy. The Mangochi Malaria Research Project (MMRP), a prospective evaluation of malaria prevention in pregnant women in rural Malawi conducted during 1987-1990, contributed to establishing new criteria for policy and program development for malaria prevention in pregnancy. The principle findings of the MMRP include: 1) populations at risk of the adverse consequences of malaria in pregnancy include women with low parity, women infected with human immunodeficiency virus, pregnancy during the high malaria transmission season, and the use of a malaria drug that is suboptimally efficacious; 2) the estimated maximum benefits of an antimalarial intervention that clears placental and umbilical cord parasitemia are a 5-12% reduction of low birth weight (LBW), an approximately 35% reduction in the risk of LBW for risks that are actually preventable once a woman has become pregnant (e.g., risks such as infectious disease or poor nutrition during gestation), and a 3-5% reduction in the rate of infant mortality; 3) the intervention must be capable of rendering the woman malaria parasite free, including clearance of parasites from the placental vascular space and umbilical cord blood; 4) other diseases adversely affect pregnancy outcome and, while the control of malaria in pregnancy may not warrant independent programming, if coupled with prevention programs to provide a range of antenatal services, the incremental costs of malaria control may prove to be highly cost-effective; and 5) the choice of a regimen must balance intervention efficacy with safety, availability, affordability, and simplicity of delivery, and several antimalarials may meet these criteria. The Malawi Ministry of Health has modified its malaria prevention in pregnancy recommendations and now faces the challenge of effective programming to improve child survival.

Africa↗

An evaluation of clinical indicators for severe paediatric illness.

To help reduce paediatric morbidity and mortality in the developing world, WHO has developed a diagnostic and treatment algorithm that targets the principal causes of death in children, which include acute respiratory infection, malaria, measles, diarrhoeal disease, and malnutrition. With this algorithm, known as the Sick Child Charts, severely ill children are rapidly identified, through the presence of any one of 13 signs indicative of severe illness, and referred for more intensive health care. These signs are the inability to drink, abnormal mental status (abnormally sleepy), convulsions, wasting, oedema, chest wall retraction, stridor, abnormal skin turgor, repeated vomiting, stiff neck, tender swelling behind the ear, pallor of the conjunctiva, and corneal ulceration. The usefulness of these signs, both in current clinical practice and within the optimized context of the Sick Child Chart algorithm in a rural district of western Kenya, was evaluated. We found that 27% of children seen in outpatient clinics had one or more of these signs and that pallor and chest wall retraction were the signs most likely to be associated with hospital admission (odds ratio (OR) = 8.6 and 5.3, respectively). Presentation with any of these signs led to a 3.2 times increased likelihood of admission, although 54% of hospitalized children had no such signs and 21% of children sent home from the outpatient clinic had at least one sign. Among inpatients, 58% of all children and 89% of children who died had been admitted with a sign. Abnormal mental status was the sign most highly associated with death (OR = 59.6), followed by poor skin turgor (OR = 5.6), pallor (OR = 4.3), repeated vomiting (OR = 3.6), chest wall retraction (OR = 2.7), and oedema (OR = 2.4). Overall, the mortality risk associated with having at least one sign was 6.5 times higher than that for children without any sign. While these signs are useful in identifying a subset of children at high risk of death, their validation in other settings is needed. The training and supervision of health workers to identify severely ill children should continue to be given high priority because of the benefits, such as reduction of childhood mortality.

Cause of Death↗

Maternal HIV infection and infant mortality in Malawi: evidence for increased mortality due to placental malaria infection.

OBJECTIVES: To examine the relationship between maternal HIV infection, placental malaria infection, and infant mortality as a first step in investigating the possibility of increased vertical transmission of HIV due to placental malaria infection. DESIGN: Retrospective analysis of data from a cohort study of mothers and infants in rural Malawi conducted from 1987 to 1990. METHODS: Pregnant women in Malawi were enrolled in a study examining chemoprophylaxis during pregnancy. At delivery, placental malaria infection status was determined. Infants born into this study were visited every 2 months for the first 2-3 years of life. Deaths were investigated using a standardized 'verbal autopsy' interview. Maternal serum collected during pregnancy was tested for antibodies to HIV-1 by enzyme-linked immunosorbent assay with Western blot confirmation. RESULTS: Overall, 138 (5.3%) of 2608 women in the study were HIV-1-seropositive. Infant mortality rates were 144 and 235 per 1000 live births for children born to HIV-seronegative and HIV-seropositive women, respectively (P < 0.001). In a multivariate model, the odds of dying during the post-neonatal period for an infant born to a mother with both placental malaria and HIV infection was 4.5 times greater than an infant born to a mother with only placental malaria, and between 2.7 and 7.7 times greater (depending on birthweight) than an infant born to a mother with only HIV infection. CONCLUSIONS: This study strongly suggests that exposure to both placental malaria infection and maternal HIV infection increases post-neonatal mortality beyond the independent risk associated with exposure to either maternal HIV or placental malaria infection. If confirmed, malaria chemoprophylaxis during pregnancy could decrease the impact of transmission of HIV from mother to infant.

Acquired Immunodeficiency Syndrome↗

Antibodies to a Plasmodium falciparum blood-stage antigen as a tool for predicting the protection levels of two malaria-exposed populations.

To evaluate the ability of antibodies to Plasmodium falciparum ring-infected erythrocyte surface antigen (Pf155/RESA) epitopes to discriminate between individuals well protected or poorly protected against malaria, a receiver operating characteristic analysis was performed in two populations living in Madagascar and Malawi. The definition of protection was based on longitudinal measurements of clinical malarial attacks during the season of high malaria transmission in the Madagascar study, and on a cross-sectional measurement of parasitemia in the Malawi study. Antibodies to peptides reproducing the 4-mer, 8-mer, and 11-mer of the Pf155/RESA were tested for their reactivities using the Falcon assay screening test-enzyme-linked immunosorbent assay. Maximal detection of poorly protected individuals (specificity = 100%) corresponded to high cutoff antibody titers (range = 1.65-3.0 optical density [OD] units in the Madagascar study and 0.67-1.42 OD units in the Malawi study) and a sensitivity less than 50%. For a given sensitivity of 50%, specificity ranged from 55% to 62% in the Madagascar study, and from 67% to 94% in the Malawi study. The antibody cutoff titers corresponding to minimal misclassification rates ranged from 0.24 to 1.73 OD units in the Madagascar study and from 0.15 to 0.55 OD units in the Malawi study. For each antibody, the highest detectability value as measured by the area under the curve was obtained for anti-R11 in the Malawi study (0.838). In demonstrating such qualities, antibodies to Pf155/RESA epitopes could be used for screening poorly protected populations in which malaria control programs have to be implemented.

Amino Acid Sequence↗

Antimalarials during pregnancy: a cost-effectiveness analysis.

Antenatal clinics (ANC) provide an avenue for interventions that promote maternal and infant health. In areas hyperendemic for Plasmodium falciparum, malaria infection during pregnancy contributes to low birth weight (LBW), which is the greatest risk factor for neonatal mortality. Using current data and costs from studies in Malawi, a decision-analysis model was constructed to predict the number of LBW cases prevented by three antimalarial regimens, in an area with a high prevalence of chloroquine (CQ)-resistant malaria. Factors considered included local costs of antimalarials, number of ANC visits, compliance with dispensed antimalarials, prevalence of placental malaria, and LBW incidence. For a hypothetical cohort of 10,000 women in their first or second pregnancy, a regimen consisting of one dose of sulfadoxine-pyrimethamine (SP) in the second trimester followed by a second dose at the beginning of the third trimester would prevent 205 cases of LBW at a cost of US$ 9.66 per case of LBW prevented. A regimen using a treatment dose of SP followed by CQ 300 mg (base) weekly would prevent 59 cases of LBW at a cost of $62 per case prevented, compared with only 30 cases of LBW prevented at a cost of $113 per case when the regimen involves initial treatment with CQ (25 mg/kg) followed by CQ 300 mg (base) weekly. In areas hyperendemic for CQ-resistant P. falciparum, a two-dose SP regimen is a cost-effective intervention to reduce LBW incidence and it should be included as part of the antenatal care package.

Antimalarials↗

Antibodies to ring-infected erythrocyte surface antigen (Pf155/RESA) protect against P. falciparum parasitemia in highly exposed multigravidas women in Malawi.

To determine whether antibodies to defined B-cell epitopes of Plasmodium falciparum antigens were related to protection against parasitemic attacks in highly exposed pregnant women, two samples of 235 with no initial P. falciparum parasitemia (NP) and 89 multigravidas who presented initial P. falciparum parasitemia (IP) were enrolled in an antimalarial prophylaxis trial in the Mangochi District in Malawi. Sera were collected under effective prophylaxis and tested for antibody measurement using FAST-ELISA. Mean antibody titers to synthetic peptides reproducing the 3 major B-cell epitopes of the ring-infected erythrocyte surface antigen (Pf155/RESA), as (EENV)4, (EENVEHDA)4 and (DDEHVEEPTVA)3, were higher in the NP than in the IP multigravidas, and this remained consistent within the season of malaria transmission (all p < 0.05). All antibodies to Pf155/RESA were positively intercorrelated within each group. Mean antibody titers to peptide (PNAN)5 reproducing the major B-cell epitope of the circumsporozoite protein (CS protein) were similar between NP and IP multigravidas in both dry and rainy season. Antibodies to Pf155/RESA epitopes may contribute to immune protection against blood-stage parasite multiplication in these highly malaria-exposed pregnant women.

Adult↗

HIV-1 infection among women of reproductive age in a rural district in Malawi.

OBJECTIVES: To determine HIV-1 seroprevalence in pregnant women attending antenatal clinics in a rural district in Malawi, and to estimate the rate of HIV-1 infection in the district among women of reproductive age. DESIGN AND SETTING: Cross-sectional survey conducted from 1987 to 1990 of women enrolled at antenatal clinics at four sites (two towns and two villages). METHODS: Questionnaires were administered and sera screened at delivery. Population infection estimates were based on national census and survey data. RESULTS: Of 3953 pregnant women tested, 283 (7.2%) were HIV-1-seropositive. Women enrolled at town sites were significantly more likely to be HIV-1-infected than village women (11.3 versus 3.9%; P < 0.001). Higher infection rates were associated with age 20-29 years, first or second pregnancy, increased education or socioeconomic status, and living within 8 km of the clinic. It was estimated that over 7300 women of reproductive age were HIV-1-infected in this rural district. CONCLUSIONS: Seroprevalence rates in pregnant women in rural towns were intermediate between rates in villages and previously documented rates in cities in Malawi. Although village sites had lower seroprevalence rates, they accounted for over half the estimated HIV-1 infection in childbearing women in this district.

Adolescent↗

Risk factors for anemia in young children in rural Malawi.

Anemia is an increasingly recognized health problem in African children. To determine the prevalence of and risk factors for anemia in young children, we enrolled 252 pregnant women and studied their newborn infants in Mangochi District in southern Malawi. At the first follow-up visit after birth at approximately two months of age, the mean hematocrit value of the 252 infants was 29.5%, and 64 infants (25%) were anemic (hematocrit value < 25%). Placental malaria infection was the strongest risk factor for an infant having anemia at the first follow-up (relative risk = 2.0, P = 0.003). Infants who had Plasmodium falciparum parasitemia at the first follow-up had lower hematocrit values than infants without parasitemia (median 28% versus 31%; P = 0.02). Neither the mother's hematocrit at enrollment, her hematocrit at delivery, sex of the infant, nor fever illness in the infant was associated with having a hematocrit less than 25% at the first follow-up. Although infants with hematocrit values less than 25% were more likely than infants with higher hematocrit values to die during the first year of life, this difference was not statically significant (relative risk = 1.7, P = 0.15). In rural Malawi, anemia commonly affects young infants, is acquired early in life, and is probably a risk factor for death in infancy. Strategies to reduce anemia in infants must address P. falciparum infection, both during pregnancy and in the first few months of life.

Anemia↗

The efficacy of antimalarial regimens containing sulfadoxine-pyrimethamine and/or chloroquine in preventing peripheral and placental Plasmodium falciparum infection among pregnant women in Malawi.

To define an effective and deliverable antimalarial regimen for use during pregnancy, pregnant women at highest risk of malaria (those in their first or second pregnancy) in an area of Malawi with high transmission of chloroquine (CQ)-resistant Plasmodium falciparum were placed on CQ and/or sulfadoxine-pyrimethamine (SP). Of 38 pregnant women who received CQ treatment followed by weekly CQ prophylaxis (CQ/CQ) for at least 45 days prior to delivery, 32% had placental malaria infection, compared with 26% of 50 pregnant women who received a treatment dose of SP followed by weekly CQ prophylaxis (SP/CQ), and only 9% of 71 pregnant women who received a two-dose SP regimen (SP/SP; given once during the second trimester and repeated at the beginning of the third trimester) (P = 0.006, by chi-square test). During the peak transmission season from April to July, 47% of the women who received CQ/CQ had placental malaria infection at delivery, as compared with 37% of the women who received SP/CQ, and 10% of women who received SP/SP (P = 0.004, by chi-square test). Among women in their first or second pregnancy, two treatment doses of SP were highly effective in decreasing the proportion of women with placental malaria infection at delivery.

Analysis of Variance↗

Use of malaria prevention measures in Malawian households.

Information on malaria prevention practices in households was obtained in a nation-wide knowledge, attitudes, and practices survey in Malawi. Of the 1,531 heads of household questioned, 55% were able to identify mosquitoes as the cause of malaria. Use of any type of malaria prevention method was reported by 52% of respondents. Among users, 47% used commercial products (insecticide, mosquito coils, bednets), and 64% used natural measures (burning leaves, dung, or wood); 11% used both. The most common commercial measure used was mosquito coils (16%) followed by insecticide spray (11%) and bednets (7%). Increasing household income and educational level of the household head were strongly correlated with use of commercial methods to prevent malaria; households with an income ranked moderate or greater were eight times more likely to have used a purchased product. Use of natural measures was correlated with lower income and educational level. Thirty-six percent of respondents reported having heard or seen information on malaria in the previous year. Use of household malaria preventive measures in Malawi is very low and income-dependent. Educational messages are required to improve understanding and use of affordable measures.

Adult↗

A nation-wide malaria knowledge, attitudes and practices survey in Malawi: objectives and methodology.

A malaria knowledge, attitudes and practices survey was conducted in Malawi during April and May, 1992, to provide policy makers and program managers with information needed to design or improve malaria control programs, to establish epidemiologic and behavioral baselines, and to identify indicators for monitoring program effectiveness. Using cluster-sample survey methodology, 1531 households, in 30 clusters of 51-52 households each, were identified and members interviewed. Interviews were conducted by trained survey teams composed of young Malawian women with secondary level education. Heads of households were asked about malaria prevention methods used and about household economics; caretakers of children were asked about treatment and health seeking behavior in a recent malaria episode in a child; and women who had been pregnant in the past 5 years were asked about their antenatal clinic utilization and malaria during pregnancy. Survey results will be used to make programmatic decisions, including developing health education messages and establishing monitoring and evaluation of malaria control activities and outcomes in Malawi.

Adult↗

Malaria knowledge, attitudes and practices in Malawi: survey population characteristics.

A national knowledge, attitudes and practices (KAP) survey was conducted in March-April 1992 to examine malaria illness and the people's response to illness and malaria prevention. Fifty-one households in each of 30 randomly selected communities were sampled and information was recorded from 1,531 households and 7,025 individuals. The population is characterized by low income (average household and per capita income were US $490 and $122, respectively) and low education levels (among adult women, 45% had no formal education and only 3.9% completed more than 8 years of schooling). Characteristics of the population were similar to those found in the 1987 national census, suggesting that the survey population was representative of the larger population of Malawi. Children under 5 years of age made up 15.8% of the population and had the highest rates of fever illness; these children experienced an estimated 9.7 cases/year of fever illness consistent with malaria. Although adults reported fever less frequently, women of reproductive age experienced an estimated 6.9 episodes of fever annually. The burden of malaria morbidity in this population is extremely high and occurs in all age groups.

Adolescent↗

Treatment of malaria fever episodes among children in Malawi: results of a KAP survey.

Caretakers of children (< 10 years of age) were questioned about management of pediatric malarial fever episodes in a nation-wide knowledge, attitudes, and practices survey conducted in Malawi. A total of 1,531 households in 30 randomly selected clusters of 51 households each were sampled and interviewed. Overall 557 caretakers reported a fever in their child in the previous 2 weeks; 43%-judged the illness as severe. Fifty-two percent of caretakers brought their febrile children to clinic. Clinic attendance was positively correlated with young age of the child (< 4 years), severe illness, and higher socioeconomic status. Seventy-four percent of clinic attenders gave their child an antimalarial; in contrast, only 42% of those not attending clinic gave an antimalarial. Optimal therapy (administration of an antimalarial promptly and at the proper dosage) was received by only 7% of febrile children. Children taken to clinic were twice as likely to receive optimal therapy as were non-attenders. Identification of critical points in the optimal therapy algorithm and characteristics of caretakers linked with sub-optimal therapy may help malaria control programs target specific groups and health education messages to improve treatment of malaria fever episodes.

Algorithms↗