Breast milk reduces the risk of illness in children of mothers with cholera: observations from an epidemic of cholera in Guinea-Bissau.

BACKGROUND: A protective effect of breastfeeding against cholera has been demonstrated in areas endemic of cholera. To assess the protection offered by breast milk from mothers living in an area that had been free from cholera for 7 years, we investigated mothers with cholera and their children during an epidemic with Vibrio cholerae El Tor in the capital of Guinea-Bissau. METHODS: Eighty mothers with clinical cholera and their children were identified, and interviewed. Blood samples for vibriocidal and antitoxin antibodies were collected from mother-and-child pairs. Breast milk samples were collected from lactating mothers. Cholera was defined as acute watery diarrhea during the epidemic and a vibriocidal reciprocal titer of 20 or above. RESULTS: Three (7%) of 42 breastfed children had cholera as defined above compared with 9 (24%) of 38 nonbreastfed children (RR for breastfed children, 0.19; 95% CI, 0.04-0.91, adjusted for age). The 3 breastfed children who developed cholera received milk containing lower concentrations of anticholera toxin IgA/total IgA (median, 2.0 units/mL) than 14 children who had serologic signs of colonization but did not develop the disease (median, 17.4 units/mL). CONCLUSIONS: The protective effect of breast milk against cholera is not confined to endemic areas. Lactating mothers with cholera should receive supportive care to continue breastfeeding.

Tuberculosis in Bissau: incidence and risk factors in an urban community in sub-Saharan Africa.

BACKGROUND: Despite the long history of tuberculosis (TB) research, population-based studies from developing countries are rare. METHODS: In a prospective community study in Bissau, the capital of Guinea-Bissau, we assessed the impact of demographic, socioeconomic and cultural risk factors on active TB. A surveillance system in four districts of the capital identified 247 adult (>or=15 years) cases of intrathoracic TB between May 1996 and June 1998. Risk factors were evaluated comparing cases with the 25,189 adults living in the area in May 1997. RESULTS: The incidence of intrathoracic TB in the adult population was 471 per 100 000 person-years. Significant risk factors in a multivariate analysis were increasing age (P < 0.0001), male sex (odds ratio [OR] = 2.58, 95% CI: 1.85, 3.60), ethnic group other than the largest group (Pepel) (OR = 1.64, 95% CI: 1.20, 2.22), adult crowding (OR = 1.68, 95% CI: 1.18, 2.39 for >2 adults in household), and poor quality of housing (OR = 1.66, 95% CI: 1.24, 2.22). Household type was important; adults living alone or with adults of their own sex only, had a higher risk of developing TB than households with husband and wife present, the adjusted OR being 1.76 (95% CI: 1.11, 2.78) for male households and 3.80 (95% CI: 1.69, 8.56) for female households. In a multivariate analysis excluding household type, child crowding was a protective factor, the OR being 0.68 (95% CI: 0.51, 0.90) for households with >2 children per household. CONCLUSIONS: Bissau has a very high incidence of intrathoracic TB. Human immunodeficiency virus (HIV), increasing age, male sex, ethnicity, adult crowding, family structure, and poor housing conditions were independent risk factors for TB. Apart from HIV prevention, TB control programmes need to emphasize risk factors such as socioeconomic inequality, ethnic differences, crowding, and gender.

Treatment of children with Plasmodium falciparum malaria with chloroquine in Guinea-Bissau.

Children with symptomatic malaria in Bissau, Guinea-Bissau were randomly assigned to treatment with a 25 mg/kg total dose of chloroquine as recommended by the National Malaria Program or with a higher total dose of 50 mg/kg. Sixty-seven and 62 children, respectively, completed the treatment and were then followed once a week for five weeks. Treatment with a dose of 50 mg/kg was significantly more effective than treatment with 25 mg/kg in preventing recrudescence. The cumulative relative risk (95% confidence interval) of having parasitemia in the low-dose group during follow-up was 0.20 (0.08-0.52) on day 21, 0.38 (0.17-0.86) on day 28, and 0.48 (0.23-0.98) on day 35. Few adverse events were reported, although more children complained of vomiting and diarrhea on day 2 in the high-dose group compared with those in the low-dose group. However, this difference was not statistically significant. We conclude that a dose of 50 mg/kg of chloroquine could be recommended for treatment of Plasmodium falciparum malaria in Bissau. To minimize the risk of side effects, this higher dose should be given divided into two daily doses over a three-day period.

The social situation of motherless children in rural and urban areas of Guinea-Bissau.

With the increasing prevalence of HIV infection and the high maternal mortality, orphans are a rapidly growing problem in Africa. However, few studies describe the social conditions of these children. Our study focuses on motherless children in urban and rural areas of Guinea-Bissau. A rural and an urban cohort of children (128 and 192, respectively) that had been followed by demographic surveillance since 1990 were identified and the relatives of these children interviewed. A control cohort of 808 individuals was also identified. Although orphan children remained disadvantaged, there were few differences between surviving motherless and control children in nutritional status, use of health care services, school attendance, quality of housing, and clothing. Motherless children moved more frequently and were more likely to live in small families, often with an older grandmother. The traditional extended family system appears to be capable of handling motherless children in a non-discriminatory fashion. However, the AIDS epidemic will continue to stress the extended family system and social services to the limit.

Persisting high hospital and community childhood mortality in an urban setting in Guinea-Bissau.

AIM: To describe paediatric hospitalization in a West African capital in relation to overall childhood mortality in the community and to evaluate the potential impact of improved management at the hospital. METHODS: Hospital data on child admissions in a 6-year period were linked to information in a community-based longitudinal surveillance system. Paediatric hospitalization rates, risk factors for hospitalizations, community mortality, in-hospital mortality and the proportion of deaths occurring at hospital were examined. RESULTS: Almost 15% of infants and 45% of children less than 5 years of age had been hospitalized, and 24% of all deaths in the community occurred in-hospital. Community infant and under-three mortality rates were 110 and 207 per 1,000 person-years, respectively. In-hospital mortality remained persistently high from 1991 to 1996 and the overall in-hospital mortality was 12%. It was found that wet season, lack of maternal schooling and living in a specific district were significant risk factors for both community and in-hospital death, whereas higher hospitalization rates were associated with better-off families. CONCLUSION: In populations with high hospitalization rates, even minor improvements in acute case management of sick children attending the hospital would be expected to result in substantial reduction in overall childhood mortality. Persistently high acute in-hospital mortality reflects the need of immediate and appropriate care at the hospital. Treatment should be free of charge, in order to minimize the impact of social inequality.

Childhood mortality after oral polio immunisation campaign in Guinea-Bissau.

Though previous studies have suggested a non-specific beneficial effect of oral polio vaccine (OPV), there has been no evaluation of the mortality impact of national polio immunization days. On the other hand, studies examining the effect of OPV and diphtheria-tetanus-pertussis (DTP) vaccines, which are usually administered together in routine immunisation programmes in low-income countries, have found no beneficial or even a negative effect on infant survival. In 1998, we used the opportunity of two national immunisation days to examine the impact of OPV administered alone on survival for the 6103 children less than 5 years of age in the Bandim Health Project's study area in Guinea-Bissau. Survival was ascertained through regular surveillance from March 1998 until the beginning of the war on June 7, 1998, the end of 1998, or the end of 1999, respectively. The child register was linked with a register for the only paediatric ward in Bissau to determine the risk of hospitalisations. Among children under 5 years of age, 82% had received 1 or 2 doses of polio vaccines during the campaign. Though polio vaccination during the campaign was associated with slightly lower mortality, this difference was not significant for all children under 5 years of age (mortality ratio (MR)=0.46 (0.18-1.15)). However, oral polio vaccination was associated with a beneficial effect for children under 6 months of age at the time of the campaign, the mortality ratio being 0.09 (95% CI 0.01-0.85) in the 3 months before the war controlling for significant background factors, including routine immunizations, antenatal consultations, and arm circumference. The polio-vaccinated children aged 0-5 months had fewer hospitalisations than children who had not been polio vaccinated (RR=0.27 (0.10-0.76)). With longer follow-up to December 1998 or December 1999, the difference in mortality gradually disappeared, the MR for polio-vaccinated children being 0.61 (0.32-1.14) and 0.83 (0.51-1.34), respectively. Among children aged 6-59 months of age, measles vaccine was associated with a 56% reduction in mortality (MR=0.44 (0.28-0.69)) and no effect of oral polio vaccine was measurable in this age group. The effect of polio vaccine among children less than 6 months of age could be due to selection bias but might also represent a non-specific beneficial immune stimulation and there is nothing to suggest that OPV might have a negative effect on infant survival. Studies of the possible non-specific effects of oral polio vaccine are warranted before OPV is withdrawn.

HIV-1 infection prevalence and incidence trends in areas of contrasting levels of infection in the Kagera region, Tanzania, 1987-2000.

This study aimed at assessing the extent to which decline in HIV infection prevalence reflects decline in incidence in 3 areas with contrasting initial exposure to the HIV epidemic in the Kagera region of Tanzania. A population sample was recruited for the baseline study in 1987 through a multistage cluster sampling technique to determine HIV prevalence. Seronegative individuals identified in the baseline and subsequent studies were followed up for 3 years to yield trends in incidence that were compared for the 3 areas. The overall age-adjusted HIV-1 prevalence in the high-prevalence area of Bukoba urban declined significantly from 24.2% in 1987 to 18.2% in 1993 and later to 13.3% in 1996 (P = 0.0001). In the medium-prevalence area of Muleba, overall age-adjusted prevalence declined significantly from 10.0% in 1987 to 6.8% in 1996 and later to 4.3% in 1999 (P = 0.0003), whereas in the low-prevalence area of Karagwe the prevalence declined from 4.5% in 1987 to 2.6% in 1999 (P = 0.01). In all 3 areas, the most significant decline was consistently observed among women in the age group 15-24 years. No age group exhibited a significant upward prevalence trend. The HIV-1 incidence for Bukoba urban declined from 47.5 to 9.1 per 1000 person-years of observation in 1989 and 1996, respectively, whereas in Muleba it decreased from 8.2 to 3.9 in 1989 and 2000, respectively. Sex-specific estimates indicated a significant decline among women in the high-prevalence area of Bukoba urban from 51.5 to 9.2 per 1000 person-years at risk (P = 0.001). It is concluded that the HIV-1 epidemic in Kagera is on the decrease as reflected by the decline in HIV-1 incidence and prevalence trends particularly among the 15-24 year olds. The decline in the 3 areas of differing magnitude implies that the HIV/AIDS epidemic may be arrested early without necessarily peaking to saturation levels.

Maternal mortality: only 42 days?

OBJECTIVE: A maternal death is defined by WHO as 'the death of a woman while pregnant or within 42 days of termination of pregnancy em leader '. The origin of the 42 days is no longer clear. In developing countries, the burden imposed by pregnancy and birth on a woman's body may extend beyond 42 days as pregnancy-related anaemia can persist for longer and vaginal haemorrhaging and risk of infections are not necessarily over after six weeks. We therefore examined duration of excess mortality after delivery in rural Guinea-Bissau. DESIGN: In a prospective cohort study, we followed 15,844 women of childbearing age with biannual visits over a period of six years, resulting in a total of 60,192 person-years-at-risk. To establish cause and timing in relation to termination of pregnancy, verbal autopsy was carried out for all deaths. Mortality rates were calculated for short time intervals after each delivery or miscarriage. RESULTS: During the observation period we registered 14,257 pregnancies and 350 deaths. One hundred and ninety-four deaths followed termination of a registered pregnancy and thus were eligible for the analysis. Eighty-two deaths occurred during the first 42 days after delivery/miscarriage. A further 16 women died in the period from 43 to 91 days after parturition, 16 between 92 and 182 days and 18 between 183 and 365 days after delivery. Compared with baseline mortality 7-12 months after delivery, women who had recently delivered had 15.9 times higher mortality (95% CI 9.8-27.4). From days 43 to 91 the mortality was still significantly elevated (RR = 2.8 [1.4-5.4]). CONCLUSION: Where living conditions are harsh, pregnancy and delivery affect the health of the woman for more than 42 days. Using the WHO definition may result in an under-estimation of the pregnancy-related part of the reproductive age mortality. Extending the definition of maternal death to include all deaths within three months of delivery may increase current estimates of maternal mortality by 10-15%.

Application of Lime ( Citrus aurantifolia ) Juice to Drinking Water and Food as a Cholera-Preventive Measure.

The protective activity of lime juice against cholera was suggested in a recent case-control study from Guinea-Bissau, On the basis of these findings, we investigated the vibriocidal properties of juice from lime ( Citrus aurantifolia ) fruits added to well water, tap water, and food samples. Well-water samples showed initial pH values from 3.5 to 4,9 whereas water samples from municipal or private taps showed initial pH values between 7.5 and 8.3, A 5-log reduction in Vibrio cholerae O1 counts to <100 CFU/ml of well water was shown for two test strains after exposure to 0.5% lime juice (pH 3.3) for 12 min. In tap water, no significant reduction in CFU of V. cholerae was found after exposure to 0% (pH 8.3) and 0.5% (pH 5.6) lime juice whereas exposure to 1.0% lime juice (pH 4.4) for 120 min caused a 5-log reduction to <100 CFU/ml of tap water for the test strains. A 3-log reduction of V. cholerae was found in food samples containing 3.5% and 5.0% lime juice after 120 min exposure. Our results show that during epidemics of cholera in areas without safe sources of drinking water, juice from citrus fruits added to water and food in palatable concentrations may be appropriate measures in reducing the transmission of cholera. However, local characteristics of the water, in particular its alkalinity, should be considered before applying this measure.