Relationship between Plasmodium falciparum malaria prevalence, genetic diversity and endemic Burkitt lymphoma in Malawi.

Endemic Burkitt lymphoma (eBL) has been linked to Plasmodium falciparum (Pf) malaria infection, but the contribution of infection with multiple Pf genotypes is uncertain. We studied 303 eBL (cases) and 274 non eBL-related cancers (controls) in Malawi using a sensitive and specific molecular-barcode array of 24 independently segregating Pf single nucleotide polymorphisms. Cases had a higher Pf malaria prevalence than controls (64.7% versus 45.3%; odds ratio [OR] 2.1, 95% confidence interval (CI): 1.5 to 3.1). Cases and controls were similar in terms of Pf density (4.9 versus 4.5 log copies, p = 0.28) and having ≥3 non-clonal calls (OR 2.7, 95% CI: 0.7-9.9, P = 0.14). However, cases were more likely to have a higher Pf genetic diversity score (153.9 versus 133.1, p = 0.036), which measures a combination of clonal and non-clonal calls, than controls. Further work is needed to evaluate the possible role of Pf genetic diversity in the pathogenesis of endemic BL.

HIV-1 incidence among male workers at a sugar estate in rural Malawi.

OBJECTIVES: To determine incidence of HIV and associated risk factors in two cohorts of men working at a sugar estate in rural Malawi. DESIGN: Prospective studies. METHODS: After counseling and obtaining informed consent, male workers were tested for HIV-1 and syphilis. Baseline HIV-seronegative men were enrolled in two follow-up studies in 1994 and 1998, and were retested for HIV and syphilis at 6-month follow-up visits. Demographic, behavioral, and medical history was collected at baseline. Cumulative HIV incidence based on Kaplan-Meier methods was estimated. HIV incidence was also estimated per 100 person-years (p-y). Crude and adjusted rate ratios for the association of risk factors with incident HIV infection were obtained using Cox proportional hazards models. RESULTS: HIV prevalence was 24.3% among 1692 men screened in 1994 and 21.0% among 1349 men screened in 1998 (p <.03). HIV incidence was extremely high during 1994 to 1995 (17.1% for that 1-year period). Incidence dramatically declined in 1996, averaging about 3.5% per year from 1996 through 1999. Among men enrolled in the 1998 cohort, HIV incidence during 1998 to 1999 was 3.8%. After controlling for potential confounders reactive syphilis was associated with a twofold risk of HIV acquisition in each cohort. CONCLUSIONS: Urgent preventive measures are needed to control the spread of HIV in this economically important occupational cohort. In addition to conventional educational messages to reduce risky sexual behavior, treatment of other sexually transmitted diseases should be considered.

Association of HIV-1 load and CD4 lymphocyte count with mortality among untreated African children over one year of age.

OBJECTIVE: To examine the association of viral load and CD4 lymphocyte count with mortality among HIV-infected children over one year of age. DESIGN: A prospective study. HIV-infected children were enrolled during the first year of life and followed for more than 2 years at the Queen Elizabeth Central Hospital in Blantyre, Malawi (southeast Africa). METHODS: Morbidity and mortality information was collected every 3 months, and physical examination and blood testing (for viral level and CD4 cell percentage) were performed every 6 months. Kaplan-Meier analyses and proportional hazards models were used to estimate survival and to examine the association of primary predictors with mortality. RESULTS: Of 155 HIV-infected children originally enrolled, 115 (74%) had viral load testing and 82 (53%) had both viral load and CD4 cell percentage testing after their first year. Among children over one year of age, significant associations were found between mortality and the log10 viral load and CD4 cell percentage in both univariate and multivariate models. Independent of the CD4 cell value, a one unit log10 increase in HIV RNA level increased the hazard of child mortality by more than twofold. Children with low CD4 cell counts (< 15%) and high viral loads (> or = 250,000 copies/ml median value) had the worst survival; children with high CD4 cell counts (> or = 15%) and low viral loads (< 250,000 copies/ml) had the best survival. CONCLUSION: As in developed countries, viral load and CD4 cell count are the main predictors of mortality among African children. Making these tests available adds to the challenges to be considered if antiviral therapies were to be adopted in these countries.

Morbidity among human immunodeficiency virus-1-infected and -uninfected African children.

OBJECTIVE: To assess patterns of morbidity and associated factors in late infancy and early childhood among human immunodeficiency virus (HIV)-infected and -uninfected African children. DESIGN: Prospective study. SETTING: The Queen Elizabeth Central Hospital, Blantyre, Malawi. PARTICIPANTS: Children with known HIV status from an earlier perinatal intervention trial were enrolled during the first year of life and followed to approximately 36 months of age. OUTCOME MEASURES: Morbidity and mortality information was collected every 3 months by a questionnaire. A physical examination was conducted every 6 months. Blood to determine CD4(+) values was also collected. Age-adjusted and Kaplan-Meier analyses were performed to compare rates of morbidity and mortality among infected and uninfected children. RESULTS: Overall, 808 children (190 HIV-infected, 499 HIV-uninfected but born to infected mothers, and 119 born to HIV-uninfected mothers) were included in this study. Of these, 109 died during a median follow-up of 18 months. Rates of childhood immunizations were high among all children (eg, lowest was measles vaccination [87%] among HIV-infected children). Age-adjusted morbidity rates were significantly higher among HIV-infected than among HIV-uninfected children. HIV-infected children were more immunosuppressed than were uninfected children. By 3 years of age, 89% of the infected children died, 10% were in HIV disease category B or C, and only approximately 1% were without HIV symptoms. Among HIV-infected children, median survival after the first occurrence of acquired immunodeficiency syndrome-related conditions, such as splenomegaly, oral thrush, and developmental delay, was <10 months. These same conditions, in addition to frequent bouts of fever, were the main morbidity predictors of mortality. CONCLUSIONS: The frequency of diseases was high, and progression from asymptomatic or symptomatic HIV disease to death was rapid. Management strategies that effectively reduce morbidity for HIV-infected children are needed.

Mortality after the first year of life among human immunodeficiency virus type 1-infected and uninfected children.

BACKGROUND: HIV-infected and uninfected children who survived their first year of life were prospectively followed in Malawi to assess levels of mortality and related risk factors during the second and third years of life. METHODS: Children with known HIV status from an earlier perinatal intervention trial were enrolled. These children [HIV-infected (Group A); HIV-uninfected but born to HIV-seropositive mothers (Group B); and children born to HIV-seronegative mothers (Group C)] were followed every 3 months until age 36 months. Mortality data were collected at each visit. Immunologic data (CD4+ percent) were collected at or immediately after enrollment. RESULTS: Overall 702 children were enrolled and 83 children died during follow-up. The mortality rate per 1000 person years of observation was 339.3 among Group A children, 46.3 among Group B children and 35.7 among Group C children. Among HIV-infected children the cumulative proportion surviving to age 24 months was 70% and those surviving to age 36 months was 55%. By age 32 months none of the severely immunosuppressed (CD4% < 15%) children had survived. The mortality differentials between HIV-infected and uninfected children persisted after adjusting for several risk factors. The major causes of death among infected children (n = 52) were wasting and respiratory conditions. CONCLUSIONS: Although all HIV-infected children had received childhood immunizations, mortality was high. Management of these children should include aggressive antimicrobial treatment, and evaluation of prophylactic regimens should be considered.

HIV infection and disturbances of vaginal flora during pregnancy.

Disturbances of vaginal flora are common among women of reproductive age. In areas of sub-Saharan Africa where the prevalence of HIV is high, the frequency of bacterial vaginosis (BV) is also high. In this study, we assessed the association of BV and other disturbances of vaginal flora with prevalent HIV infection in two cross-sectional studies among pregnant women in urban Malawi. The prevalence of HIV-1 was 23% in 1990 and 30% in 1993. Overall, 30% of the women had BV, 59% had mild or moderate disturbance of vaginal flora, and only 11% had normal vaginal flora. Increasing prevalence of HIV was significantly associated with increasing severity of disturbance of vaginal flora (p < .00001, chi2 trend test). This trend of increased prevalence persisted after controlling for concurrent sexually transmitted diseases (STDs), sexual activity, and socioeconomic factors. After multivariate adjustment for potential confounders, the odds ratio for the association of BV with prevalent HIV infection was 3.0 (95% confidence interval [CI], 2.4-3.8), that of moderate vaginal disturbance with HIV infection was 2.2 (95% CI, 1.7-2.8), and that of mild vaginal disturbance with HIV infection was 1.6 (95% CI, 1.3-2.1). Among women with BV, HIV infection was higher among younger women than older, implying more recent infection. Although these studies were cross-sectional, our data suggest that BV could be associated with increased susceptibility to HIV infection.

PIP: While ulcerative and nonulcerative STDs have been shown to be associated with HIV transmission, the potential association of HIV transmission with more frequent genital conditions which cause no inflammation of the vaginal or cervical mucosa have been inadequately studied. Bacterial vaginosis (BV) is characterized by disturbances in the vaginal flora resulting in the loss of lactobacilli, an increase in other mainly anaerobic flora, and an increased vaginal pH. Reproductive-age women commonly experience disturbances of vaginal flora, and in areas of sub-Saharan Africa in which HIV prevalence is high, there is also a high frequency of BV. The authors explored the association of BV and other disturbances of vaginal flora with prevalent HIV infection in 2 cross-sectional studies among pregnant women in urban Malawi. 23% of the 6684 women tested for HIV-1 infection in 1990 were seropositive, as well as 30% of 2464 women tested in 1993. Overall, 30% of the women had BV, 59% had mild or moderate disturbance of vaginal flora, and 11% had normal flora. An increasing prevalence of HIV was significantly associated with increasing severity of disturbance of vaginal flora, even after controlling for concurrent STDs, sexual activity, and socioeconomic factors. After multivariate adjustment for potential confounders, the odds ratio for the association of BV with prevalent HIV infection was 3.0, that of moderate vaginal disturbance with HIV infection was 2.2, and that of mild vaginal disturbance with HIV infection was 1.6. Among women with BV, HIV infection was higher among younger women than older, implying more recent infection. These findings suggest that BV could be associated with increased susceptibility to HIV infection.

Bacterial vaginosis and disturbances of vaginal flora: association with increased acquisition of HIV.

BACKGROUND: Cross-sectional studies suggest an association between bacterial vaginosis (BV) and HIV-1 infection. However, an assessment of a temporal effect was not possible. OBJECTIVES: To determine the association of BV and other disturbances of vaginal flora with HIV seroconversion among pregnant and postnatal women in Malawi, Africa. DESIGN: Longitudinal follow-up of pregnant and postpartum women. METHODS: Women attending their first antenatal care visit were screened for HIV after counselling and obtaining informed consent. HIV-seronegative women were enrolled and followed during pregnancy and after delivery. These women were again tested for HIV at delivery and at 6-monthly visits postnatally. Clinical examinations and collection of laboratory specimens (for BV and sexually transmitted diseases) were conducted at screening and at the postnatal 6-monthly visits. The diagnosis of BV was based on clinical criteria. Associations of BV and other risk factors with HIV seroconversion, were examined using contingency tables and multiple logistic regression analyses on antenatal data, and Kaplan-Meier proportional hazards analyses on postnatal data. RESULTS: Among 1196 HIV-seronegative women who were followed antenatally for a median of 3.4 months, 27 women seroconverted by time of delivery. Postnatally, 97 seroconversions occurred among 1169 seronegative women who were followed for a median of 2.5 years. Bacterial vaginosis was significantly associated with antenatal HIV seroconversion (adjusted odds ratio = 3.7) and postnatal HIV seroconversion (adjusted rate ratio = 2.3). There was a significant trend of increased risk of HIV seroconversion with increasing severity of vaginal disturbance among both antenatal and postnatal women. The approximate attributable risk of BV alone was 23% for antenatal HIV seroconversions and 14% for postnatal seroconversions. CONCLUSIONS: This prospective study suggests that progressively greater disturbances of vaginal flora, increase HIV acquisition during pregnancy and postnatally. The screening and treating of women with BV could restore normal flora and reduce their susceptibility to HIV.

Trends of HIV-1 and sexually transmitted diseases among pregnant and postpartum women in urban Malawi.

OBJECTIVES: To examine rates of HIV-1 and sexually transmitted disease (STD) among pregnant and postpartum women in urban Malawi, Africa. DESIGN: Serial cross-sectional surveys and a prospective study. METHODS: Three major surveys were conducted in 1990, 1993 and 1994/1995. Consecutive first-visit antenatal women and women giving birth at the Queen Elizabeth Central Hospital were tested for HIV and STD after counseling and obtaining informed consent. Unlinked, anonymous HIV testing was also conducted on smaller samples of antenatal women in the same hospital to provide annual prevalence data. HIV-seronegative postpartum women from the 1990 and 1993 surveys were enrolled in a prospective study to determine HIV incidence. RESULTS: HIV seroprevalence rose from 2.0% in 1985 to 32.8% in 1996, a 16-fold increase. The highest age-specific HIV prevalence was in the following age-groups: 20-24 years during 1990, 25-29 years during 1993, and 30-34 years during 1996. Among 1173 women followed for a median of 30.9 months, HIV incidence was 5.98 per 100 person-years in women aged < 20 years and declined steadily in older women. The prevalence of STD significantly declined among both HIV-positive and negative women. This decline in STD prevalence, however, was not accompanied by increased condom use over time. CONCLUSIONS: Among urban childbearing women in Malawi, incidence of HIV is highest among young women while, currently, prevalence is highest among older women. Recent declines in STD prevalence suggest that HIV prevention programs are having an impact either through improved STD diagnosis and treatment or reduced risk behaviors. Sequential cross-sectional STD prevalence measures may be useful in monitoring effectiveness of STD and HIV prevention activities.

PIP: Prevalence rates of HIV-1 and other sexually transmitted diseases (STDs) among pregnant and postpartum women were investigated in sequential, cross-sectional studies (1990, 1993, and 1994-95) conducted at Queen Elizabeth Central Hospital in Blantyre, Malawi. Annual anonymous, unlinked testing revealed a linear increase in HIV-1 prevalence among antenatal patients from 2.0% in 1985 to 32.8% in 1996. Analysis of demographic attributes of women enrolled in the 1990 and 1993 surveys of consecutive, first-visit antenatal women (n = 6603 and 2161, respectively) and the 1994-95 study of all women giving birth at the hospital during a 6-month period (n = 6964) indicated that HIV-infected women were most likely to be young, with fewer pregnancies, and be more educated. The highest age-specific HIV prevalence shifted from 20-24 years in 1990 to 30-34 years in 1996, indicating an aging cohort of women who became infected at a younger age. Reported lifetime use of condoms increased from 5.6% in 1990 to 17.5% in 1993, then declined to 4.9% in 1995; condom use was consistently higher among HIV-positive than HIV-negative women. The prevalence of all STDs (syphilis, trichomoniasis, gonorrhea, and genital warts and ulcers) declined significantly during 1990-96, with the most consistent decreases recorded among HIV-positive women. In a follow-up study of 1173 HIV-seronegative, postpartum women evaluated for 2302 person-years (average duration, 30.9 months), 97 seroconverted (4.21/100 person-years). The seroconversion rate declined steadily from 21.26/100 person-years in 1990 to 1.11/100 person-years in 1994-95. These findings are consistent with those from other sub-Saharan African countries, indicating a rapid increase in HIV prevalence followed by stabilization within about 10 years of the onset of the epidemic. The large decline in STD prevalence in the antenatal population suggests that Malawi's national AIDS prevention program is having an impact, either through improved STD diagnosis and treatment or reduced risk behaviors.

Effect of cleansing the birth canal with antiseptic solution on maternal and newborn morbidity and mortality in Malawi: clinical trial.

OBJECTIVE: To determine if cleansing the birth canal with an antiseptic at delivery reduces infections in mothers and babies postnatally. DESIGN: Clinical trial; two months of no intervention were followed by three months of intervention and a final month of no intervention. SETTING: Queen Elizabeth Central Hospital (tertiary care urban hospital), Blantyre, Malawi. SUBJECTS: A total of 6965 women giving birth in a six month period and their 7160 babies. INTERVENTION: Manual wipe of the maternal birth canal with a 0.25% chlorhexidine solution at every vaginal examination before delivery. Babies born during the intervention were also wiped with chlorhexidine. MAIN OUTCOME MEASURES: Effects of the intervention on neonatal and maternal morbidity and mortality. RESULTS: 3635 women giving birth to 3743 babies were enrolled in the intervention phase and 3330 women giving birth to 3417 babies were enrolled in the non-intervention phase. There were no adverse reactions related to the intervention among the mothers or their children. Among infants born in the intervention phase, overall neonatal admissions were reduced (634/3743 (16.9%) v 661/3417 (19.3%), P < 0.01), as were admissions for neonatal sepsis (7.8 v 17.9 per 1000 live births, P < 0.0002), overall neonatal mortality (28.6 v 36.9 per 1000 live births, P < 0.06), and mortality due to infectious causes (2.4 v 7.3 per 1000 live births, P < 0.005). Among mothers receiving the intervention, admissions related to delivery were reduced (29.4 v 40.2 per 1000 deliveries, P < 0.02), as were admissions due to postpartum infections (1.7 v 5.1 per 1000 deliveries, P = 0.02) and duration of hospitalisation (Wilcoxon P = 0.008). CONCLUSIONS: Cleansing the birth canal with chlorhexidine reduced early neonatal and maternal postpartum infectious problems. The safety, simplicity, and low cost of the procedure suggest that it should be considered as standard care to lower infant and maternal morbidity and mortality.

PIP: A clinical trial of the effects of cleansing both the birth canal and the newborn with an antiseptic indicates that this simple procedure substantially reduces early neonatal and maternal postpartum infection. The antiseptic used, a 0.25% chlorhexidene solution, has been shown to reduce neonatal morbidity due to group B streptococcus and can neutralize HIV. Enrolled in the study were 6965 women giving birth to 7160 infants at Queen Elizabeth Central Hospital in Blantyre, Malawi, in a 6-month period in 1994. 2 months of no intervention were followed by 3 months of intervention and a final month of no intervention. Significant differences were recorded between the 3743 infants delivered during the intervention phase and the 3417 controls in terms of overall neonatal admissions (16.9 vs. 19.3/1000 live births), admissions for neonatal sepsis (7.8 vs. 17.9/1000 live births), overall neonatal mortality (28.6 vs. 36.9/1000 live births), and mortality due to infectious causes (2.4 vs. 7.3/1000 live births). Significant differences also were found between the 3635 mothers in the intervention group and the 3330 controls in delivery-related admissions (29.4 vs. 40.2/1000 deliveries), admissions due to postpartum infection (1.7 vs. 5.1/1000 deliveries), and the average duration of hospitalization (48.7 vs. 50.2 hours). The cleansing procedure was easily administered, required almost no extra staff time, and cost less than US $0.10 per patient, making it appropriate for standard care.

Evaluation of a quantitative double ELISA strategy for confirmation and differentiation of HIV infection.

The current HIV pandemic is complicated by the spread of distinct types and subtypes of HIV. The currently used conventional diagnostic tests have shown limitations in the detection of antibodies against all HIV-1 subtypes, as demonstrated by recent identification of HIV-1 subtype O. To evaluate quantitatively the diagnostic potential of a double ELISA strategy for the detection and partial differentiation of HIV-1, HIV-1 subtype O and HIV-2 infections blood samples were examined at five different test centers: Blantyre, Malawi; Abidjan and Daloa, Ivory Coast; Yaoundé, Cameroon; Munich, Germany. All tests results, including ELISA extinction values and Western blot profiles, were forwarded to Munich for final interpretation. An indirect anti-HIV-1/2 ELISA and a competitive anti-HIV-1 ELISA were used in combination for the initial screening of blood specimens. All anti-HIV positive and anti-HIV negative samples were subjected to immunoblot analysis. Independent of the diversity of the extinction profiles, and of the test manufacturer, the quantitative evaluation of the ELISA extinction values could define two extinction areas with a 100% predictive value for HIV-1 seropositivity and HIV seronegativity; extinction values > 2 by the indirect ELISA and < 0.2 by the competitive ELISA for an anti-HIV-1 subtype A to I positive result; extinction values < 0.2 by the indirect ELISA and > 1.0 by the competitive ELISA for an anti-HIV negative result. Additionally, the quantitative evaluation of the extinction profile provides partial information on the HIV-1 subtype as far as the distinction in group M and group O is concerned. In conclusion, the quantitative evaluation of this double ELISA strategy can reduce the number of blood specimens that require additional confirmatory testing in developing countries and can be superior to the immunoblot method during early seroconversion.

Cervical abnormalities, human papillomavirus, and human immunodeficiency virus infections in women in Malawi.

Cervical lavage samples and Pap smears were obtained from 284 women in Malawi to evaluate the association between human papillomavirus (HPV) and human immunodeficiency virus (HIV) infections. Squamous intraepithelial lesions were present in 15% (17/16) of HIV-seropositive and 7% (11/152) of HIV-seronegative women (P=.05) and in 23% (19/83) of HPV polymerase chain reaction (PCR)-positive and 4% (6/156) of HPV PCR-negative women (P<.001). HPV DNA was detected in 23% of HIV-uninfected women but in 60% of HIV-infected women with <300 CD4 cells/mm(3) (P<.002). High-risk HPV types 16 and 18 constituted half of the identified types. HPV DNA in previously HPV-positive women was detected more often than in HIV-seropositive abnormal cervical cytology than uninfected ones and were more likely to have persistent HPV infections. Early detection of HPV and regular monitoring of HIV-related cervical lesions may be important in HIV-infected women.