Prevalence of HIV and malaria: a cross-sectional study on Bioko Island,Equatorial Guinea

Malaria and HIV are two of the most severe public health problems in Africa. However, epidemiological data on Bioko Island is scarce. To investigate the prevalence of malaria and HIV infections and assess association of malaria and HIV infections and possible confounding factors, we performed a cross-sectional survey of people of malaria-endemic Bioko Island, Equatorial Guinea. A cross-sectional study of 1 526 subjects was carried out to determine the prevalence of malaria and HIV infection in Malabo region hospital on Bioko Island. Questionnaires were administered and venous blood samples were drawn for malaria parasites and HIV detection. The prevalence of participants infected with malaria and HIV in this area were 13.8% and 6.6% respectively. The average prevalence of co-infection for malaria and HIV was 0.92%. HIV-infection was significantly associated with the age and gender. Malaria infections were significantly associated with the age. This study showed that the prevalence of HIV and malaria on Bioko Island was higher than expected, although the co-infection prevalence of malaria and HIV was low. The results also indicated that malaria and HIV infections lead to more public health risk to youngsters and women.     

Predictive factors of malaria in travelers to areas where malaria is endemic

BACKGROUND: The differentiation of malaria from other causes of fever is difficult. The development of tools for rapid and specific clinical diagnosis is of paramount importance for the identification of individuals infected with malaria. METHOD: A 4-year prospective study to identify the clinical and biological variables associated with malaria included all patients suspected of having malaria who presented in the emergency department (ED) of a French hospital. RESULTS: Of 783 patients admitted to the ED with suspected malaria, 145 had positive findings of a thick smear for Plasmodium species, mainly Plasmodium falciparum (90.3%). In univariate analysis, the following 12 variables were significantly associated with diagnosis of malaria: older than 30 years, male sex, immigration to France from an area where malaria is endemic, a visit to sub-Saharan Africa, insufficient antimalaria prophylaxis, fever, chills, absence of diarrhea, a leukocyte count within the reference range, thrombocytopenia, and increased lactate dehydrogenase and bilirubin levels. In multivariate analysis, the factors predictive of malaria included a visit to sub-Saharan Africa (odds ratio [OR], 7.7; 95% confidence interval [CI], 2.8-21.3), a temperature of at least 38.5 degrees C (OR, 6.2; 95% CI, 2.8-13.3), chills (OR, 3.0; 95% CI, 1.4-6.6), thrombocytopenia (OR, 16.5; 95% CI, 7.1-38.3), and abnormally high total bilirubin levels (OR, 21.5; 95% CI, 6.4-72.5). However, alone or combined, these features had insufficient sensitivity (95.0%) and low specificity (55.0%) for the diagnosis of malaria. CONCLUSIONS: Malaria should be suspected in all patients presenting with complaints after travel to an area where malaria is endemic, and these patients should undergo blood microscopy.     

HIV, malaria parasites, and acute febrile episodes in Ugandan adults: a case-control study.

BACKGROUND: In sub-Saharan Africa, co-infection with HIV and malaria is probably very common. Although an interaction between the two infections is biologically plausible, it has not been investigated thoroughly. OBJECTIVES: To evaluate the association firstly between co-infection with HIV and malaria parasites and the occurrence of acute fever, and secondly between HIV infection and clinical malaria, defined as the presence of acute fever and malaria parasites. METHODS: A hospital-based case-control study was conducted in Gulu District (northern Uganda), an area endemic for malaria and with a high HIV prevalence. HIV testing and malaria parasite quantification were performed on 167 consecutive adult out-patients with acute fever and no signs or symptoms of localized infection, and on 134 consecutive adult in-patients without fever who were admitted for non-HIV-related trauma or elective surgery. RESULTS: No significant association with acute fever was observed for single infection with either malaria parasites [adjusted odds ratio (AOR), 1.75; 95% confidence interval (CI), 0.73-4.21] or HIV (AOR, 1.01; 95% CI, 0.51-2.03), whereas a significant association was observed for co-infection (AOR, 9.75; 95% CI, 1.19-80.00). An association was found between HIV infection and clinical malaria (AOR, 2.34; 95% CI, 0.89-6.17); the association became statistically significant when the definition of clinical malaria included a cut-off for parasite density (50th percentile; i.e., 586 parasites/microl; AOR, 3.61; 95% CI, 1.04-12.52). CONCLUSIONS: Despite the limited statistical power, the results of our study show an association between HIV infection and clinical malaria; if confirmed, this finding could be important for public health in sub-Saharan Africa.     

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.     

Bacteremia in Malawian children with severe malaria: prevalence, etiology, HIV coinfection, and outcome

BACKGROUND: Previous prospective studies of bacteremia in African children with severe malaria have mainly included children with cerebral malaria, and no study has examined the impact of human immunodeficiency virus (HIV) infection. We examined the prevalence and etiology of bacteremia and the impact of HIV infection on bacteremia in Malawian children with severe malaria, as well as the impact of bacteremia and HIV infection on outcome. METHODS: From 1996 until 2005, blood for culture was obtained on admission from all children admitted with severe malaria during the rainy season to the Paediatric Research Ward at the Queen Elizabeth Central Hospital in Blantyre, Malawi. HIV testing was performed prospectively from 2001 to 2005 and retrospectively for those admitted from 1996 to 2000. Multivariate regression analysis examined independent risk factors for bacteremia and death. RESULTS: Sixty-four (4.6%) of 1388 children with severe malaria had bacteremia; nontyphoidal Salmonellae (NTS) accounted for 58% of all bacteremias. The prevalence of any bacteremia and of NTS bacteremia was highest in children with severe malarial anemia (11.7% and 7.6%), compared with the prevalence in children with cerebral malaria and severe anemia (4.7% and 3.8%) and in those with cerebral malaria alone (3.0% and 0.9%). HIV infection status was determined in 1119 patients. HIV prevalence was 16% (and was highest in those with severe malaria anemia, at 20.4%), but HIV infection was not significantly associated with bacteremia. Neither bacteremia nor HIV infection was associated with death. CONCLUSIONS: Antibiotics are not routinely indicated for children with severe malaria in this region, in which HIV is endemic. However, antibiotic therapy should be used to treat NTS infection if bacteremia is suspected in children with severe malarial anemia.     

Impact of HIV-associated immunosuppression on malaria infection and disease in Malawi

BACKGROUND: Human immunodeficiency virus (HIV) infection and malaria coexist in much of Africa. Previous studies differ in their findings on the interactions between the 2 infections. METHODS: Adults living with HIV infection in Blantyre, Malawi, were enrolled in a longitudinal observational study from September 2002 to August 2004. Malaria blood smears were obtained monthly and for any illness suggestive of malaria. Complete evaluations of all illness episodes were conducted, regardless of malaria smear results. RESULTS: The incidence of clinical malaria episodes was higher in participants with CD4 cell counts <200 cells/mm3 than in those with CD4 cell counts >500 cells/mm3. The trend was preserved when increasingly specific definitions of malaria disease were used. The prevalence of malaria infection was not associated with CD4 cell count. In per-visit analysis, lower CD4 cell counts were associated with higher incidences of pneumonia, sepsis, and tuberculosis but not of malaria. Severe malaria was rare, with only 3 cases in 591 person-years of observation. Parasite density and CD4 cell count were independent risk factors for fever. CONCLUSIONS: Profoundly immunosuppressed adults with HIV infection require more-frequent treatment for uncomplicated malaria, but malaria infection and disease are less strongly associated with HIV-associated immunosuppression than are other opportunistic infections. Where malaria is common, the high incidence of fever found among immunosuppressed adults may lead to misclassification of illness episodes as malaria.     

Prevalence and predictors of maternal peripheral malaria parasitemia in central Mozambique

Malaria infection during pregnancy (MiP) is heterogeneously distributed even in malaria-endemic countries. Program planners require data to facilitate identification of highest-priority populations for MiP control. Using data from two cross-sectional studies of 5,528 pregnant women in 8 neighboring sites in Mozambique, we described factors associated with maternal peripheral parasitemia by using logistic regression. Principal multivariate predictors of maternal peripheral parasitemia were gravidity (odds ratio [OR] = 2.29, 95% confidence interval [CI] = 1.60-3.26 for primigravidae and OR = 1.61, 95% CI = 1.29-2.01 for secundigravidae compared with gravidity > or = 3); age (OR = 0.96 per year, 95% CI = 0.94-0.99); study site (OR = 1.45, 95% CI = 1.34-1.56 to 5.32, 95% CI = 4.92-5.75) for comparison with the reference site; and no maternal education (OR = 1.38, 95% CI = 1.15-1.66) compared with any education. Other predictors (in subgroups) were bed net use (OR = 0.49, 95% CI = 0.48-0.50); preventive sulfadoxine-pyrimethamine doses (OR = 0.25, 95% CI = 0.24-0.25); and infection with human immunodeficiency virus (HIV) (OR = 1.49, 95% CI = 1.11-2.00). Programmatic priorities should respond to heterogeneous distribution of multiple risk factors, including prevalence of malaria and infection with HIV, and maternal socioeconomic status.     

Nutritional and socio-demographic risk indicators of malaria in children under five: a cross-sectional study in a Sudanese rural community

This paper reports the results of a cross-sectional study of the association between nutritional, environmental and socio-demographic factors, and malaria occurrence among 445 children under 5 years of age in a Sudanese rural community. The overall frequency of malaria as defined by a history of clinical illness during the previous 2 months was 27%. Malaria occurrence was positively associated with the degree of malnutrition as assessed by weight-for-age. The age-adjusted odds ratio for mild malnutrition and history of malaria was 1.2 (95% confidence interval (CI): 0.7-2.0) and for moderate malnutrition and malaria was 2.1 (95% CI: 1.1-4.0). Malaria was less frequent among children 0-11 months of age relative to older children (OR = 0.4; 95% CI:0.2-0.7), and was inversely associated with ownership of a refrigerator (OR = 0.5; 95% CI:0.36-0.94), an indicator of socio-economic status. Indicators of crowding were the best predictors of the risk of malaria. Less malaria was observed in households with three or more rooms (OR = 0.6; 95% CI:0.37-0.98) and more malaria was observed in households with more than five people (OR = 2.5; 95% CI:1.4-4.5). Malaria was slightly, but not significantly, more frequent among boys and was associated with anaemia, which was probably an outcome of malaria in the past. These data suggest that undernutrition may increase the risk of malaria, and draw attention to the importance of socio-economic and environmental factors in relation to this disease. These relationships deserve further examination in prospective follow-up studies that are better able to evaluate the temporal relations of malnutrition and malaria.     

HIV-associated morbidity, mortality and diagnostic testing opportunities among inpatients at a referral hospital in northern Tanzania

Hospitalized patients with HIV infection are among the most likely to benefit from the expanding availability of anti-retroviral therapy in sub-Saharan Africa. Between 1990 and 2000, 3667 people known to be HIV-infected were admitted to Kilimanjaro Christian Medical Centre (KCMC) in Moshi, northen Tanzania. The level of inpatient mortality among these patients varied from 15%-21%, and the proportion of the HIV-infected patients admitted who were female increased significantly, from 45% at the start of the study period to 52% at the end (P <0.001). When the medical records for 1683 of the HIV-infected patients who had been admitted between 1996 and 2001 were reviewed, the most prevalent diagnoses on admission were found to be pulmonary tuberculosis (21%), malaria (14%) and gastro-enteritis/diarrhoea (12%) among the adults, and non-tubercular pulmonary infection (21%), pulmonary tuberculosis (19%) and gastro-enteritis/diarrhoea (12%) among the children. The crude odds ratios (OR) for inpatient death were greatest for adults presenting with meningitis [OR=3.7; 95% confidence interval (CI)=2.1-6.7], septicaemia (OR=2.9; CI=1.2-7.3) or renal disease (OR=2.6; CI=1.2-5.7), and mortality was higher for men than for women (OR=1.4; CI=1.1-1.8). A single-day, point-prevalence survey in September 2001, among the KCMC's inpatients, identified HIV infection in 21% of those surveyed, many (44%) of the patients found positive being previously unaware of their infection. HIV infection remains a major cause of hospitalization and mortality in Moshi. A policy of routine testing would increase the number of HIV infections detected, allowing improvements in case management and in the prevention of infection.     

Malaria among adult inpatients in two Tanzanian referral hospitals: A prospective study

Most malaria research in sub-Saharan Africa has focused on children and pregnant women, but malaria among hospitalized adults in this region is poorly characterized. In this prospective study, we assessed the prevalence and clinical characteristics of malaria among the inpatient adults in two hospitals in Tanzania. We enrolled adults admitted with suspected malaria and performed routine thick blood smear (BS) and malaria rapid diagnostic tests (RDT). We also assessed malaria parasite clearance rates. We considered malaria status ‘confirmed’ or ‘excluded’ only in patients with two concordant tests. Malaria polymerase chain reaction (PCR) was performed in a subset of patients with discordant BS and RDT. After BS and RDT were performed on 579 adults with suspected malaria, malaria was excluded in 458/579 (79.1%) and confirmed in 16/579 (2.8%). One hundred and five out of 579 (18.1%) had discordant results. The prevalences of positive BS and positive RDT were 102/579 (17.6%) and 35/579 (6.0%), respectively, with only fair agreement (Kappa = 0.354, p < 0.0001). PCR results agreed with RDT in 35/35 (100%) of patients with a negative RDT but positive BS. PCR results also agreed with RDT in 9/13 (69.2%) of cases with a positive RDT but negative BS. Clinical correlates of malaria by multivariable analysis included subjective fever (OR 3.6 [1.0–12.3], p = 0.04), headache (OR 3.1 [1.2–8.0], p = 0.02) and vomiting (OR 2.7 [1.2–6.4], p = 0.02). Malaria parasite clearance was significantly delayed in the HIV-infected group. Our study demonstrated only fair agreement between RDT and BS malaria tests among Tanzanian adult inpatients with suspected malaria. PCR generally agreed with RDT results. HIV was associated with delayed parasite clearance in adults with malaria. We recommend the routine use of RDTs for malaria diagnosis among adults admitted to hospitals in sub-Saharan Africa.     

Severe malaria and concomitant bacteraemia in children admitted to a rural Mozambican hospital

Objectives  To describe the prevalence, aetiology and prognostic implications of coexisting invasive bacterial disease in children admitted with severe malaria in a rural Mozambican Hospital.
Methods  Retrospective study of data systematically collected from June 2003 to May 2007 in a rural Mozambican hospital, from all children younger than 5 years admitted with severe malaria.
Results  Seven thousand and forty-three children were admitted with a diagnosis of malaria. 25.2% fulfilled the criteria for severe malaria. 5.4% of the children with severe malaria and valid blood culture results had a concomitant bacteraemia. Case fatality rates of severe malaria cases rose steeply when bacteraemia was also present (from 4.0% to 22.0%, P  < 0.0001), and bacteraemia was an independent risk factor for death among severe malaria patients (adjusted OR 6.2, 95% CI 2.8–13.7, P  = 0.0001). Streptococcus pneumoniae , Gram-negative bacteria, Staphilococcus aureus and non-typhoid Salmonella (NTS) were the most frequently isolated microorganisms among severe malaria cases. Their frequency and associated case fatality rates (CFR) varied according to age and to syndromic presentation. Streptococcus pneumoniae had a relatively low CFR, but was consistently associated with severe malaria syndromes, or anaemia severity groups. No clear-cut relationship between malarial anaemia and NTS bacteraemia was found.
Conclusions  The coexistence of malaria and invasive bacterial infections is a frequent and life-threatening condition in many endemic African settings. In Mozambique, S. pneumoniae is the leading pathogen in this interaction, possibly as a consequence of the high HIV prevalence in the area. Measures directed at reducing the burden of both those infections are urgently needed to reduce child mortality in Africa.     

Developmental impairments following severe falciparum malaria in children

OBJECTIVE: Neurological deficits are reported in children after cerebral malaria (CM) but little is known about the prevalence and characteristics of persisting neurocognitive consequences. The prevalence of developmental impairments following other complications of falciparum malaria, such as multiple, prolonged or focal seizures, is not known. Thus, our objective was to investigate the long-term developmental outcome of CM and malaria with complicated seizures (M/S). METHODS: We followed up a cohort of children previously exposed to CM or M/S and children unexposed to either condition. All children between 6 and 9 years of age, exposed to CM, and an equal number of children exposed to M/S were identified from databases of hospital admissions from 1991 to 1998. The unexposed group was randomly selected from a census database. The children's performance was measured using assessments of cognition, motor, speech and language, hearing and vision. A parental questionnaire was used to identify children with epilepsy. RESULTS: CM group scores were significantly lower than unexposed group scores on the assessments of higher level language (adjusted mean difference -1.63, 95% CI: -2.99 to -0.27), vocabulary (-0.02, 95% CI: -0.04 to -0.01), pragmatics (OR 2.81, 95% CI: 1.04-7.6) and non-verbal functioning (-0.33, 95% CI: -0.61 to -0.06). The areas of significantly reduced functioning for the M/S group were concentrated on phonology (OR 2.74, 95% CI: 1.26-5.95), pragmatics (OR 3.23, 95% CI: 1.2-8.71) and behaviour (OR 1.8, 95% CI: 1.0-3.23). The performance of the active epilepsy group was significantly poorer than that of the group without epilepsy on the tests of comprehension, syntax, pragmatics, word finding, memory, attention, behaviour and motor skills. CONCLUSIONS: CM and M/S are associated with developmental impairments. If these impairments persist, this may have implications for least 250,000 children in Sub-Saharan Africa each year. Active epilepsy significantly increases the risk of cognitive and behavioural problems in children with a history of severe malaria.     

Risk of Plasmodium falciparum infection during a malaria epidemic in highland Kenya, 1997

Malaria epidemics in highland areas of East Africa have occurred with increasing frequency since the late 1980s, but the actual risk of Plasmodium falciparum infection in children and adults during these epidemics has not been well characterized. During a malaria epidemic in a highland area of Kenya, risk of infection was assessed in 50 adults (> or =18 years old) and 32 children (< or =8 years old) after treatment and parasitologic clearance with sulfadoxine-pyrimethamine treatment. Over a 10-week period, 36 of the 82 study participants (43.9%) became infected. The risk of infection was similar in children and adults (hazard ratio for children = 1.21, 95% CI: 0.63-2.33). These findings contrast with the age-related protection from infection reported in areas of stable, intense transmission, and demonstrate that during malaria epidemics, both children and adults in highland areas of Kenya are at high risk of infection.     

Routine, voluntary HIV testing in Durban, South Africa: correlates of HIV infection

Background

Routine HIV testing is increasingly recommended in resource‐limited settings. Our objective was to evaluate factors associated with a new diagnosis of HIV infection in a routine HIV testing programme in South Africa.

Methods

We established a routine HIV testing programme in an out‐patient department in Durban, South Africa. All registered adults were offered a rapid HIV test; we surveyed a sample of tested patients.

Results

During the 12‐week study, 1414 adults accepted HIV testing. Of those, 463 (32.7%) were HIV‐infected. Seven hundred and twenty (50.9%) were surveyed. Compared with married women, unmarried men were at the highest risk of HIV [odds ratio (OR) 6.84; 95% confidence interval (CI) 3.45–23.55], followed by unmarried women (OR 5.90; 95% CI 3.25–10.70) and married men (OR 4.00; 95% CI 2.04–7.83). Age 30–39 years (compared with ≥50 years; OR 5.10; 95% CI 2.86–9.09), no prior HIV test (OR 1.45; 95% CI 1.07–2.27) and an imperfect HIV knowledge score (OR 2.32; 95% CI 1.24–4.35) were also associated with HIV infection.

Conclusion

In a routine HIV testing programme in South Africa, rates of previously undiagnosed HIV were highest among men, young and unmarried patients, and those with poorer HIV knowledge. Better interventions are needed to improve HIV knowledge and decrease HIV risk behaviour.     

Urban malaria and anaemia in children: a cross-sectional survey in two cities of Ghana

OBJECTIVE: To describe the epidemiology of urban malaria, an emerging problem in sub-Saharan Africa. METHOD: Cross-sectional surveys of communities in Accra and Kumasi, Ghana, determining risk factors for malaria infection and anaemia in children aged 6-60 months. RESULTS: Malaria prevalence rates ranged from 2% to 33% between urban communities. 47.1% of children were anaemic (Hb<11.0 g/dl). Factors associated with malaria prevalence were low socio-economic status, age and anaemia. The attributable risks of anaemia and severe anaemia (Hb<8.0 g/dl) caused by malaria were 5% and 23% respectively. CONCLUSIONS: Malaria in urban areas displayed a heterogeneity and complexity that differed from the rural environment, which has important implications for malaria control. Marked intra-city variation indicates the importance of targeting specific areas or districts. The most vulnerable group, the urban poor, should be prioritized when designing control measures. This would require careful assessment of the malaria risk pattern in any city to guide an integrated control program.     

Clinical burden and correlates of HIV and malaria co-infection,in northwest Nigeria

The clinical burden of malaria and HIV/AIDS in sub-Saharan Africa is well-described, but the dynamics of the interaction between the two diseases remain poorly understood. Using a cross-sectional study design, we assessed the prevalence and predictors of malaria infection among HIV-positive patients attending a referral center in urban Kano, northwest Nigeria. Structured questionnaires covering socio-demographic characteristics, HIV diagnosis and treatment, malaria preventive practices, clinical events and treatment were administered to HIV-infected adults (n = 363). Information from questionnaires was supplemented with data from case notes. In the preceding year, nearly a third of respondents (32.2%; 95% CI = 27.4–37.3) had at least one episode of fever, diagnosed as malaria on blood film examination. Half of all respondents (53.5%) admitted to using insecticide treated nets (ITN). One-third (35.8%) of participants were on malaria chemoprophylaxis at the time of the study. Female sex (adjusted Odds Ratio [aOR] = 1.54, 95% confidence interval (CI): 1.32–2.73), immunosuppression (CD4+ cell count <350/μL vs. 600/μL, aOR = 2.41, 95% CI 1.23–3.74) and non-use of ITN (aOR = 1.97, 95% CI 1.17–2.85) predicted the occurrence of clinical malaria in patients. We report a high burden of malaria in HIV-infected patients attending a tertiary facility in urban Kano, Nigeria. Health communication, standardized protocols and ITN distribution should be integrated into comprehensive HIV programs in this setting.     

HIV infection,malaria, and pregnancy: a prospective cohort study in Kigali,Rwanda

In order to study the relation between human immunodeficiency virus (HIV) infection and malaria in women, during and after pregnancy, a prospective cohort study was initiated at the Centre Hospitalier de Kigali in Rwanda through routine voluntary and confidential HIV screening in antenatal clinics. At inclusion in the cohort of all HIV-positive and an equivalent number of HIV-negative pregnant women, between 21 and 28 weeks of gestation, sociodemographic characteristics and medical history during the current pregnancy were collected; screening for malaria (tick blood smear) and anemia and a CD4 lymphocyte count were systematically performed. Each woman enrolled had a monthly follow-up until 6 months after delivery. A clinic was implemented that was accessible and free of charge to every woman during the study period between scheduled visits. Malaria infection was systematically screened in case of fever or other compatible symptoms. The cohort included 228 HIV-positive and 229 HIV-negative women. At inclusion, malaria prevalence was 8.0% in HIV-positive women and 3.5% in HIV-negative women (P < 0.04). Over the study period, the incidence of malaria was 6.2 per 100 women-months in the HIV-positive group and 3.5 in the HIV-negative group (relative risk [RR] = 1.7, 95% confidence interval [CI] = 1.4-2.3). The bulk of the difference occurred postpartum. The Kaplan-Meier 9-month probability of remaining free of malaria infection was 51.8% in HIV-positive women and 65.2% in HIV-negative women (P = 0.013). When taking account in the same multivariate model (including HIV infection, primiparity, CD4 lymphocytes, anemia, and education level), positive HIV serostatus remained the only factor significantly associated with malaria infection (RR = 1.4, CI = 1.1-1.6; P = 0.016). Our study prospectively documents the association between malaria and maternal HIV infection and highlights the increased risk of malaria occurrence in all HIV-infected women. Strategies to reduce the malaria morbidity during pregnancy should be reinforced in areas of high HIV seroprevalence.     

Changing pattern of malaria in Bissau, Guinea Bissau

Objective To describe the epidemiology of malaria in Guinea‐Bissau, in view of the fact that more funds are available now for malaria control in the country. Methods From May 2003 to May 2004, surveillance for malaria was conducted among children less than 5 years of age at three health centres covering the study area of the Bandim Health Project (BHP) and at the outpatient clinic of the national hospital in Bissau. Cross‐sectional surveys were conducted in the community in different malaria seasons. Results Malaria was overdiagnosed in both health centres and hospital. Sixty‐four per cent of the children who presented at a health centre were clinically diagnosed with malaria, but only 13% of outpatient children who tested for malaria had malaria parasitaemia. Only 44% (963/2193) of children admitted to hospital with a diagnosis of malaria had parasitaemia. The proportion of positive cases increased with age. Among hospitalized children with malaria parasitaemia, those less than 2 years old were more likely to have moderate anaemia (RR = 1.27; 95% CI: 1.02–1.56) (P = 0.03) or severe anaemia (RR = 1.67; 95% CI: 1.25–2.24) (P = 0.0005) than older children. The prevalence of malaria parasitaemia in the community was low (3%, 53/1926). Conclusion In Bissau, the prevalence of malaria parasitaemia in the community is now low and malaria is over‐diagnosed in health facilities. Laboratory support will be essential to avoid unnecessary use of the artemisinin combination therapy which is now being introduced as first‐line treatment in Bissau with support from the Global Fund.     

A community-based study to examine the effect of a youth HIV prevention intervention on young people aged 15-24 in South Africa: results of the baseline survey

OBJECTIVES: To determine whether South African youths living in communities that had either of two youth human immunodeficiency virus (HIV) prevention interventions [(a) loveLife Youth Centre or (b) loveLife National Adolescent Friendly Clinic Initiative] would have a lower prevalence of HIV, sexually transmitted infections (STIs), and high risk sexual behaviours than communities without either of these interventions. METHODS: In 2002 the baseline survey of a quasi-experimental, community-based study was conducted in South Africa. In total 33 communities were included in three study arms (11 communities per study arm). The final sample included 8735 youths aged 15-24 years. All participants took part in a behavioural interview and were tested for HIV, gonorrhoea (Neisseria gonorrhoeae) and Chlamydia (Chlamydia trachomatis). RESULTS: HIV prevalence was 20.0% among females and 7.5% among males (OR 3.93 95% CI 2.51-6.15). There were no significant differences between study arms for HIV, NG or CT prevalence at baseline. In multiple regression analyses, HIV was significantly associated with NG infection (OR 1.96 95% CI 1.24-3.12) but not with CT infection. Youths who reported >1 lifetime partner were also significantly more likely to be infected with HIV (OR 1.98 95% CI 1.55-2.52), as were those who reported ever having engaged in transactional sex (OR 1.86 P = 0.02) or having had genital ulcers in the past 12 months (OR 1.71 P < or = 0.001). CONCLUSIONS: HIV prevention programmes must ensure that gender inequities that place young women at greater risk for HIV infection are urgently addressed and they must continue to emphasize the importance of reducing the number of sexual partners and STI treatment.     

Short report: entomologic inoculation rates and Plasmodium falciparum malaria prevalence in Africa.

Epidemiologic patterns of malaria infection are governed by environmental parameters that regulate vector populations of Anopheles mosquitoes. The intensity of malaria parasite transmission is normally expressed as the entomologic inoculation rate (EIR), the product of the vector biting rate times the proportion of mosquitoes infected with sporozoite-stage malaria parasites. Malaria transmission intensity in Africa is highly variable with annual EIRs ranging from < 1 to > 1,000 infective bites per person per year. Malaria control programs often seek to reduce morbidity and mortality due to malaria by reducing or eliminating malaria parasite transmission by mosquitoes. This report evaluates data from 31 sites throughout Africa to establish fundamental relationships between annual EIRs and the prevalence of Plasmodium falciparum malaria infection. The majority of sites fitted a linear relationship (r2 = 0.71) between malaria prevalence and the logarithm of the annual EIR. Some sites with EIRs < 5 infective bites per year had levels of P. falciparum prevalence exceeding 40%. When transmission exceeded 15 infective bites per year, there were no sites with prevalence rates < 50%. Annual EIRs of 200 or greater were consistently associated with prevalence rates > 80%. The basic relationship between EIR and P. falciparum prevalence, which likely holds in east and west Africa, and across different ecologic zones, shows convincingly that substantial reductions in malaria prevalence are likely to be achieved only when EIRs are reduced to levels less than 1 infective bite per person per year. The analysis also highlights that the EIR is a more direct measure of transmission intensity than traditional measures of malaria prevalence or hospital-based measures of infection or disease incidence. As such, malaria field programs need to consider both entomologic and clinical assessments of the efficacy of transmission control measures.