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Biomedical subjects

J G Breman

Publications and source records attributed to J G Breman.

At least 37 records · Page 2Linked to original sources
PubMed1996

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↗
PubMed1995

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↗
PubMed1995

The effectiveness of insecticide-impregnated bed nets in reducing cases of malaria infection: a meta-analysis of published results.

The use of insecticide-impregnated bed nets to minimize human-vector contact may reduce the incidence of malaria. Consequently, several field trials have evaluated their effectiveness as a malaria prevention strategy. A meta-analysis of published reports of field trials that measured the incidence of infections was performed to provide a measure of the effectiveness of insecticide-treated bed nets in preventing clinical malaria. Subsetted analyses were performed on the 10 field trials to calculate pooled incidence rate ratios of infection among the study groups. For the studies comparing insecticide-impregnated bed nets with untreated bed nets, the summary incidence rate ratio for acquiring malarial infections was 0.757 (95% confidence interval [CI] = 0.612-0.938), representing a reduction of 24%. For the studies comparing permethrin-impregnated bed nets with controls without bed nets, the summary incidence rate ratio was 0.497 (95% CI = 0.417-0.592) (Rothman-Boice heterogeneity statistics = 17.27 [P = 0.004] and 23.55 [P = 0.0003], respectively). These data suggest that insecticide-impregnated bed nets are effective in preventing malaria, decreasing the incidence rate ratio by approximately 50% in field trials performed to date.

Animals↗
PubMed1994

Evaluation of national malaria control programmes in Africa.

Evaluation is an essential management tool for the improvement of public health programmes or projects. As malaria morbidity and mortality continue to increase in most countries in Africa, international agencies and malaria control programme managers have identified the strengthening of programme evaluation as an important strategy for improving the efficiency and effectiveness of malaria control programmes. Managers can develop an evaluation strategy only after they have defined programme objectives and planned specific programme activities. Indicators should be directly related to programme objectives and should be selected on the basis of the following criteria: their validity; reliability; ability to detect change within a reasonable time period and as a result of successful programme implementation; ability to be interpreted; and usefulness in guiding programme change. Only those indicators that can be measured with available programme resources should be selected. Managers will also need to identify the sources of indicator data and to determine how often each indicator will be measured. Programme managers should develop criteria or indicators for the following: programme policies and plans; the process of programme implementation; the outcomes of malaria control interventions in disease management and prevention; and programme impact in terms of reductions in malaria-related mortality and morbidity. Key issues related to the management of evaluation activities within a national programme include the need to begin with available resources and build incrementally; to explore options for administering evaluation activities; to select, train and supervise staff who carry out evaluation activities; to develop quality control strategies; and to ensure that data are managed and communicated in ways that support effective programme decision-making. For evaluation to lead to improvements in malaria control programmes it must be clearly defined as a part of the programme management process. Programme managers should lead this developmental process, ensuring that evaluation methods produce the information they need to monitor and improve their programmes at reasonable cost.

Africa↗
PubMed1993

Plasmodium falciparum-associated anemia in children at a large urban hospital in Zaire.

Chloroquine-resistant Plasmodium falciparum malaria and human virus (HIV) infection through blood transfusions used to treat malaria-associated anemia are causes of increasing morbidity and mortality among children in Africa. To evaluate the role of malaria and other risk factors for pediatric anemia, we conducted a study of children brought to the emergency ward of a large urban hospital in Kinshasa, Zaire. A total of 748 children ages six through 59 months were enrolled; 318 (43%) children were anemic (hematocrit < 33%), including 74 (10%) who were severely anemic (hematocrit < 20%). Plasmodium falciparum parasites were detected in 166 children (22%); hematocrits for these children (mean 25.8%) were significantly lower than for aparasitemic children (mean 33.7%; P < 10(-6)). Fever with splenomegaly (odds ratio [OR] = 6.5, P = 0.02), parasitemia (OR = 3.5, P < 0.001), lower socioeconomic status (OR = 2.0, P = 0.004), and malnutrition (OR = 1.8, P = 0.06) were independently associated with anemia in a multivariate model. Recent antimalarial therapy was also associated with a lower hematocrit, suggesting that chloroquine may have aggravated the anemia. A reassessment of the effectiveness of strategies to diagnose and treat malaria and malnutrition is necessary to decrease the high prevalence of anemia and the resultant high rate of blood transfusions in areas endemic for malaria and HIV.

Analysis of Variance↗
PubMed1993

Effectiveness of permethrin-impregnated bed nets and curtains for malaria control in a holoendemic area of western Kenya.

The effectiveness of village-wide use of permethrin-impregnated bed nets or eave, window, and door curtains as control measures for Plasmodium falciparum malaria was evaluated during two successive high-transmission seasons in western Kenya. Pairs of villages were assigned to one of three study groups: bed net, curtain, or control. Clinical, parasitologic, and entomologic measures were made from March to July 1990 and again 12 months later. When compared with the controls in 1990 and 1991, we observed a marked reduction in the incidence of P. falciparum infections in children less than six years old in the bed net villages (reduced by 40% and 48%) and a smaller but still significant reduction in the curtain villages (10% and 33%). Significant reductions were also seen in the incidence of P. falciparum parasitemias greater than 2,500/mm3 in the bed net group (reduced by 44% and 49%) and curtain group (16% and 32%). Additionally, we observed significant reductions in the incidence of documented fevers in association with P. falciparum parasitemia in bed net (reduced by 63%) and curtain villages (53%) when compared with controls. Entomologic inoculation rates in both bed net and control villages decreased by more than 50% below control values during both high transmission seasons. The results of this study, together with a 1988 study in the same area during the low transmission season, show that bed nets offer greater year-round of protection against P. falciparum infection than curtains. However, during the high transmission season, this technique reduces the frequency of P. falciparum infection rather than preventing it entirely.

Animals↗
PubMed1992

Treatment of chloroquine-resistant malaria in African children: a cost-effectiveness analysis.

Because chloroquine (Cq)-resistant Plasmodium falciparum (CRPF) has now spread throughout most of Africa, the efficacy and practicability of other drugs such as amodiaquine (Aq), and pyrimethamine-sulfadoxine (PS), for the treatment of fever needs to be assessed. We used a decision-analysis model to compare the cost and effectiveness of Cq, Aq, and PS. The variables considered were the probability of P. falciparum infection, drug compliance, minor and lethal side effects of the drug, the level of drug resistance in the community, and case-fatality rates associated with treatment. The measures of effectiveness were the number of malaria-related fever episodes cured parasitologically with each treatment and the number of malaria deaths prevented in children 6-59 months old. Cost-effectiveness comparisons were made for cases cured and deaths prevented. For treating 100,000 febrile episodes, Cq, PS, and Aq cost US$1812, US$2622, and US$3044, respectively. Cost of the drug, compliance, and the level of CRPF had the greatest effect on the cost-effectiveness ratio. The prevalence of high-level drug resistance (RIII) was the most important determinant of the cost-effectiveness. In a scenario with high-level CRPF, treatment with Cq costs US$0.47 to cure one patient and US$2.29 to prevent one death compared with US$0.05 and US$1.52 for treatment with PS. When the prevalence of RIII-level CRPF is greater than 14-31% (depending on the level of compliance), the most cost-effective treatment is PS, despite its 45% greater cost. Decision analysis models will be useful for malaria control planners as strategies are reconsidered in the 1990s.

Africa↗
PubMed1991

Tumor necrosis factor and severe malaria.

To investigate the relation of tumor necrosis factor-alpha (TNF alpha) to Plasmodium falciparum infection, plasma TNF alpha concentrations were measured in Zairian children with severe malaria, mild malaria, or other illnesses. The initial geometric mean plasma concentration of TNF alpha among 61 children with P. falciparum infection, (71 pg/ml) was higher than the level in 26 severely ill, aparasitemic children (10 pg/ml; P less than .001). Among 29 parasitemic children, initial geometric mean TNF alpha levels decreased from 77 to 5 pg/ml (P less than .001) at day 7. TNF alpha levels increased with parasite density and were associated with hyperparasitemia, severe anemia, hypoglycemia, and young age but not with cerebral malaria or fatal outcome. However, TNF alpha levels were elevated equally in children with cerebral malaria and with other signs of severe malaria. With multiple linear regression, TNF alpha levels were elevated independently in children with hyperparasitemia (P = .001) and severe anemia (P = .04). In this study, high TNF alpha levels were associated with several manifestations of severe malaria and were not specific to cerebral malaria.

Animals↗
PubMed1990

Trends and risk factors for HIV-1 seropositivity among outpatient children, Kinshasa, Zaire.

To investigate recent trends in pediatric HIV-1 infection and the early impact of a blood screening program begun in one hospital in 1987 in Kinshasa, Zaire, we evaluated 1110 consecutive children seen in the pediatric emergency ward of the city's largest hospital in November 1988. The HIV-1 seroprevalence was 5.0%, not significantly higher than the rate of 3.8% found in 1986 (P = 0.2). The seropositivity rate was bimodally distributed; children less than 6 months of age had a higher rate (12.6%) than children 6-11 months old (1.9%; OR = 7.6; P less than 0.0001) and children 1-13 years old (4.1%; OR = 3.4; P less than 0.0001). Seropositive children greater than or equal to 1 year of age were more likely than seronegative children to be anemic and to have signs of malnutrition. A previous blood transfusion was associated with HIV-1 seropositivity among children greater than or equal to 1 year of age (OR = 5.4, P less than 0.0005), but not among younger children. Fifty-two per cent of seropositive children greater than or equal to 1 year of age received a transfusion (etiological fraction = 42%). The association with seropositivity was higher for those who had received a transfusion before 1987 than for those who had received a transfusion since 1987 (OR = 4.8, P = 0.01). These findings suggest a relatively stable, high pediatric HIV-1 seroprevalence in Kinshasa and a decreased but continued risk of transfusions. Expansion of currently limited blood transfusion screening programs, and the development of new strategies for limiting transfusions and preventing severe anemia, are needed.

Adolescent↗
PubMed1990

Permethrin-impregnated curtains and bed-nets prevent malaria in western Kenya.

The effectiveness of permethrin-impregnated (0.5 g/m2) bed-nets and curtains as malaria control measures was evaluated in Uriri, Kenya in 1988. One hundred five families were randomly assigned to 1 of 3 study groups (control, bed-net, or curtain). All participants were cured of parasitemia with pyrimethamine/sulfadoxine. Selective epidemiologic and entomologic parameters were measured weekly, while knowledge, attitude, and practices surveys were conducted at the beginning and end of the 15 week study. Plasmodium falciparum infections per person week at risk were significantly higher in the control group than in either the curtain group (5.42 vs. 2.35 cases/100 person weeks risk) or the bed-net group (5.42 vs. 3.77 cases/100 person weeks risk). The curtain group had fewer infections per person week at risk than the bed-net group (2.35 vs. 3.77 cases/100 person weeks risk). A difference was found in clinical malaria among the groups: 45% of persons in the bed-net and curtain groups vs. 30% of those in the control group reported no episodes of fever and chills (chi 2, P less than 0.05). Indoor resting Anopheles gambiae or An. funestus were found on 94 occasions in the control houses, but only twice in the treated houses during weekly visits to each house over the study period (chi 2 P less than 0.001). The pyrethrum knockdown method produced similar results with a total of 195, 23, and 3 An. gambiae and An. funestus collected in the control, bed-net, and curtain houses during the same period, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

[Estimation of vital statistics in rural areas of northern Haiti using a simplified sampling method].

In September 1983, we selected 30 villages in four rural counties of northern Haiti for a partial census and malaria prevalence survey. A cohort of 1,577 persons was enumerated in this census. Survey teams revisited the same houses in these villages in September 1984 and updated the previous census, inquiring about all listed family members. We administered an additional questionnaire to each household concerning the occurrence over the past year of deaths, births, pregnancies, and migration. Among the 1,218 persons who had been followed for one year, there were 21 deaths (crude mortality rate: 17 per 1,000 population; 95% confidence interval [95% CI]: 12 per 1,000, 25 per 1,000) and 35 births (birth rate: 29 per 1,000 population year; 95% CI: 19 per 1,000, 38 per 1,000). The infant mortality rate was 171 per 1,000 live births (95% CI: 81 per 1,000, 315 per 1,000), and the mortality rate for children less than 5 years old was 36 per 1,000 (95% CI: 24 per 1,000, 56 per 1,000). Although small sample surveys are subject to limitations of precision dependent on sample size, they can be a simple method by which researchers may estimate vital statistics for rural areas of less-developed countries.

Epidemiologic Methods↗
PubMed1990

Sensitivity of Plasmodium falciparum to chloroquine and sulfadoxine/pyrimethamine in Nigerian children.

The in vivo sensitivity of Plasmodium falciparum to chloroquine and sulfadoxine/pyrimethamine was evaluated in children under 5 years of age in two areas of southern Nigeria in 1987. A modification of the WHO Standard Field and Extended Tests (in vivo) was used, with follow-up on days, 2, 3, 7, and 14 after treatment with 25 mg chloroquine per kg body weight given over 3 days, or with standard doses of sulfadoxine/pyrimethamine. Clinical and parasitological evaluations were performed. At Igbo Ora, in Oyo State, where by day 7 chloroquine was clinically successful in 94.4% of 36 children and sulfadoxine/pyrimethamine in 91.7% of 36 children, there were no parasitological failures in either treatment group. Fever regressed significantly more rapidly with chloroquine than with sulfadoxine/pyrimethamine. At Oban, in Cross River State, initial parasite densities decreased markedly with the chloroquine regimen but 63.6% of 44 children were parasitological failures on days 3, 7, or 14; and all of the 26 children who failed parasitologically and completed follow-up were successfully treated with sulfadoxine/pyrimethamine. By day 7, clinical success was demonstrated for 77.3% of the children treated with chloroquine. The in vitro sensitivity to chloroquine, quinine, and mefloquine at Igbo Ora indicated that isolates of P. falciparum were sensitive to chloroquine and quinine, but had reduced sensitivity to mefloquine. Because of its continued clinical efficacy, chloroquine remains the recommended treatment for children with uncomplicated malaria in Nigeria. Health providers are, however, encouraged to maintain supplies of sulfadoxine/pyrimethamine as an alternative and to refer patients promptly if necessary.

Animals↗
PubMed1989

Lack of efficacy of pyrimethamine prophylaxis in pregnant Nigerian women.

To evaluate the efficacy of pyrimethamine on the blood stage (suppressive prophylaxis) and liver stage (causal prophylaxis) of Plasmodium falciparum in pregnant women, in vivo and in vitro field studies were conducted in Ilorin, Nigeria, from Jan 1 to June 30, 1988. For pregnant women with P falciparum infections who received 25 mg of pyrimethamine weekly for suppressive prophylaxis, 67% (59/88) of in vivo and 60% (6/10) of in vitro tests showed pyrimethamine resistance. A second group of parasitaemic and parasite-free pregnant women was enrolled to evaluate the efficacy of pyrimethamine as a primary tissue schizonticide; after receiving a curative dose of chloroquine (25 mg/kg), half the women were given 25 mg of pyrimethamine weekly and half received no prophylaxis. Parasitologic failure rates did not differ between the pyrimethamine-treated (8/34) and the control (11/37) groups during the 16-week follow-up. Thus, pyrimethamine is not effective for suppressive or causal prophylaxis in pregnant women in Ilorin.

Adolescent↗
PubMed1989

Formulation of malaria treatment policy for children in Côte d'Ivoire as chloroquine resistant Plasmodium falciparum spreads into west Africa.

To develop a malaria treatment policy for children with Plasmodium falciparum, an in vivo and in vitro chloroquine (CQ) sensitivity study was conducted in Côte d'Ivoire in September 1986. The efficacy of a single dose of CQ (10 mg base kg-1, C10) was tested with assessment of subjects on Days 2 and 7 after treatment; 108 (99%) of 109 children were aparasitaemic on Day 7. Of 33 isolates of P. falciparum tested in vitro, two (6%) were resistant to CQ. Although C10 appeared effective clinically and parasitologically in Côte d'Ivoire, a treatment dose of 25 mg of CQ base kg-1 (C25), over three days, was recommended as first-line therapy for malaria. This was because in vivo CQ-resistance will soon spread into other West African countries including Côte d'Ivoire, the C25 dose still retains clinical effectiveness in most partially-immune persons living in areas with low-level chloroquine resistance, and alternate drugs are more expensive.

Animals↗
PubMed1989

Monitoring selective components of primary health care: methodology and community assessment of vaccination, diarrhoea, and malaria practices in Conakry, Guinea. ACSI-CCCD team.

The Africa Child Survival Initiative-Combatting Childhood Communicable Diseases (ACSI-CCCD) Project is a primary health care activity that focuses on antenatal care, immunization, diarrhoeal disease control, and malaria control in children under 5 years of age. In order to gauge progress made in the project, a community-based health interview survey to measure simultaneously several prevention and treatment indicators was carried out in 1986 in Conakry, Guinea. A sample of 1415 caretakers and their 2048 children aged under 5 years was visited using a cluster sampling technique. The survey documented the levels of literacy and health education awareness of the caretakers, measured the vaccination coverage levels for children and women of childbearing age, and determined treatment practices for diarrhoea and malaria. Of the 637 women who reported having given birth in the previous 12 months, 96% had visited an antenatal clinic, but only 49% had had two or more doses of tetanus toxoid, and 13% took weekly chemoprophylaxis against malaria. The vaccination coverage for measles was 16% for children aged 12-23 months. Oral rehydration therapy (ORT) was given to 16% of children with diarrhoea; however, only 43% of those who were administered ORT at home were treated according to standard guidelines. Of children with diarrhoea, 51% were given antidiarrhoeal or antimicrobial drugs by caretakers. Fever was treated at home for 79% of the febrile children, and 43% of those with fever also visited health units. The use of injectable antimalarials and prolonged treatments with chloroquine were common. Combining findings from a population-based community study with an assessment of practices in health facilities can provide reliable information for the implementation and monitoring of selective components of primary health care.

Africa, Western↗