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The study investigates sex differences in the prevalence of undernutrition in sub-Saharan Africa. Undernutrition was defined by Z-scores using the CDC-2000 growth charts. Some 128 Demographic and Health Surveys (DHS) were analysed, totalling 700,114 children under-five. The results revealed a higher susceptibility of boys to undernutrition. Male-to-female ratios of prevalence averaged 1.18 for stunting (height-for-age Z-score Z-score Z-score Z-scores

Risk of death from undernutrition is thought to be higher in younger than in older children, but evidence is mixed. Research also demonstrates sex differences whereby boys have a higher prevalence of undernutrition than girls. This analysis described mortality risk associated with anthropometric deficits (wasting, underweight and stunting) in children 6–59 months by age and sex. We categorised children into younger (6–23 months) and older (24–59 months) age groups. Age and sex variations in near-term (within 6 months) mortality risk, associated with individual anthropometric deficits were assessed in a secondary analysis of multi-country cohort data. A random effects meta-analysis was performed. Data from seven low-or-middle-income-countries collected between 1977 and 2013 were analysed. One thousand twenty deaths were recorded for children with anthropometric deficits. Pooled meta-analysis estimates showed no differences by age in absolute mortality risk for wasting (RR 1.08, p = 0.826 for MUAC < 125 mm; RR 1.35, p = 0.272 for WHZ < −2). For underweight and stunting, absolute risk of death was higher in younger (RR 2.57, p < 0.001) compared with older children (RR 2.83, p < 0.001). For all deficits, there were no differences in mortality risk for girls compared with boys. There were no differences in the risk of mortality between younger and older wasted children, supporting continued inclusion of all children under-five in wasting treatment programmes. The risk of mortality associated with underweight and stunting was higher among younger children, suggesting that prevention programmes might be justified in focusing on younger children where resources are limited. There were no sex differences by age in mortality risk for all deficits.

The study investigates the complex relationships between circumcision and HIV prevalence in Lesotho, using Demographic and Health surveys (DHS) conducted in 2004, 2009 and 2014. Before the HIV epidemic, about half of the male adult population was circumcised as part of a traditional custom, and this proportion increased markedly after 2008 with the campaigns of Voluntary Medical Male Circumcision (VMMC), while HIV prevalence stayed at the same level. In 2004, HIV prevalence was higher in circumcised groups than in intact groups (RR=1.49, 95% CI=1.20-1.86). This relationship changed over time, and was inversed in 2014 (RR=0.86; 95% CI=0.70-1.06). The changing relationship seems to be due to an interaction with education, with more educated men being more circumcised and having less HIV over time. A multivariate analysis showed no net effect of circumcision on HIV, after controlling for wealth, education, and indicators of marriage and sexual behaviour. A small net effect of VMMC was found, probably due to condom use. In couple studies, the effect of circumcision and VMMC on HIV was not significant, with similar transmission from female to male and male to female. The study questions the amount of effort and money spent on VMMC in Lesotho.

ObjectiveTo investigate whether children with concurrent wasting and stunting require therapeutic feeding and to better understand whether multiple diagnostic criteria are needed to identify children with a high risk of death and in need of treatment.DesignCommunity-based cohort study, following 5751 children through time. Each child was visited up to four times at 6-month intervals. Anthropometric measurements were taken at each visit. Survival was monitored using a demographic surveillance system operating in the study villages.SettingNiakhar, a rural area of the Fatick region of central Senegal.ParticipantsChildren aged 6–59 months living in thirty villages in the study area.ResultsWeight-for-age Z-score (WAZ) and mid-upper arm circumference (MUAC) were independently associated with near-term mortality. The lowest WAZ threshold that, in combination with MUAC, detected all deaths associated with severe wasting or concurrent wasting and stunting was WAZ ConclusionsA combination of MUAC and WAZ detected all near-term deaths associated with severe anthropometric deficits including concurrent wasting and stunting. Therapeutic feeding programmes may achieve higher impact if WAZ and MUAC admission criteria are used.

Objective:To investigate trends in child anthropometry in Senegal between 1990 and 2015 and relate them with potential causes. Several hypotheses were tested: changes in health status, income, diet and socio-economic status.Design:Statistical analysis of trends in anthropometric data: height, weight, BMI and associated Z-scores calculated with the CDC-2000 standard (Centers for Disease Control and Prevention): height-for-age (HAZ), weight-for-age (WAZ) and weight-for-height (WHZ). Trends were fitted with linear regression models and were related with changes in health and socio-economic status.Setting:Nine nationally representative samples of Senegalese children aged 12–59 months, taken between 1986 and 2017 by Demographic and Health Surveys (DHS).Participants:Children aged 12–59 months.Results:Over the 25 years of investigation, the average height of children increased by +1·88 cm, their average weight by +0·10 kg, but their BMI decreased by −0·53 kg/m2. Corresponding changes expressed in Z-scores were +0·454 in HAZ, +0·109 in WAZ and −0·302 in WHZ. This pattern of decreasing stunting while increasing wasting was correlated with decreasing child mortality, despite small changes in income per capita and in adult heights or BMI. Largest improvements in HAZ were among the lower socio-economic strata, while largest declines in WHZ were among higher socio-economic strata.Conclusions:Decline in stunting appeared associated primarily with the control of infectious diseases, also responsible for the mortality decline. Increase in wasting was surprising. It appears associated with small changes in income per capita, and therefore in diet, in a context of increasing height.

Age at menarche was investigated using data collected from demographic surveys (WFS, DHS) conducted in Nigeria between 1982 and 2018, all of which were based on large representative samples of the female population. Linear-logistic regressions were used to estimate mean age at menarche, its trends and its risk factors. Mean age at menarche had underwent a marked secular decline from 15.02 years for girls born in 1933 to 13.78 years for girls born in 2003. In multivariate analysis, height (stature), body mass index (BMI), level of education and household wealth had independent effects on age at menarche, whereas urban residence had no effect. Socioeconomic gradients were large: +9 years of schooling was associated with a –0.52 year decrease in age at menarche, and +2 standard deviations in household wealth with a –0.33 year decrease. The impact of anthropometry was even greater: +2 standard deviations in height was associated with a –0.99 year decrease in age at menarche, and +2 standard deviations in BMI with a –1.42 year decrease. Northern provinces had a higher mean age at menarche than southern provinces. Compared with independent sources, long-term trends in age at menarche, as well as their fluctuations, appeared to be correlated with trends and fluctuations in income per capita and in under-five mortality, but not with divergent trends in adult height.

BackgroundExcess male morbidity and mortality is well recognised in neonatal medicine and infant health. In contrast, within global nutrition, it is commonly assumed that girls are more at-risk of experiencing undernutrition. We aimed to explore evidence for any male/female differences in child undernutrition using anthropometric case definitions and the reasons for differences observed.MethodsWe searched: Medline, Embase, Global health, Popline and Cochrane databases with no time limits applied. Eligible studies focused on children aged 0-59 months affected by undernutrition where sex was reported. In the meta-analysis, undernutrition-specific estimates were examined separately for wasting, stunting and underweight using a random effects model.Results76 studies were identified: 46/76 studies were included in the meta-analysis. In 20 which examined wasting, boys had higher odds of being wasted than girls (pooled OR 1.26, 95% CI 1.13-1.40). 39 examined stunting: boys had higher odds of stunting than girls (pooled OR 1.31 95% CI 1.24-1.39). 25 explored underweight: boys had higher odds of being underweight than girls (pooled OR 1.19, 95% CI 1.07-1.32). There was some limited evidence that the female advantage indicating lower risk of stunting and underweight was weaker in South Asia than other parts of the world.44/76 (58%) studies discussed possible reasons for boy/girl differences; 11/76 (14%) cited studies with similar findings with no further discussion; 21/76 (28%) had no sex difference discussion. 6/44 studies (14%) postulated biological causes, 21/44 (48%) social causes and 17/44 (38%) to a combination.ConclusionOur review indicates that undernutrition in children under 5 is more likely to affect boys than girls, though the magnitude of these differences varies and is more pronounced in some contexts than others. Future research should further explore reasons for these differences and implications for nutrition policy and practice.Key QuestionsWhat is already known?Undernutrition (wasting, stunting, and underweight) is a public health problem affecting millions of children aged under 5 years globally.Although higher neonatal and infant morbidity/mortality for boys is well described, little attention has been given to sex differences in the field of undernutrition due to an assumption that girls are very often disadvantaged over boys.What are the new findings?In most settings studied, undernutrition is more common among boys than girls, though the extent of these differences varies and is reversed in a few contexts.Both biological and social mechanisms have been proposed to be responsible for the observed differences as well as a combination of the two.What do the new findings imply?Greater awareness of actual sex differences is needed within the field of nutrition. While sex-specific data is routinely analysed and reported in nutrition surveys it should be used in nutrition programming to better identify and understand what differences exist. Analysis should assess if the sex balance in programme admissions is reflective of the population undernutrition burden.Further research is needed to understand the mechanisms that lead to sex and gender differences in undernutrition and their implications. Better epidemiological understanding is a priority, as is work to explore their consequent effects on morbidity and mortality.

The study analysed the HIV/AIDS situation in Zambia six years after the onset of mass campaigns of Voluntary Medical Male Circumcision (VMMC). The analysis was based on data from Demographic and Health Surveys (DHS) conducted in 2001, 2007 and 2013. Results show that HIV prevalence among men aged 15–29 (the target group for VMMC) did not decrease over the period, despite a decline in HIV prevalence among women of the same age group (most of their partners). Correlations between male circumcision and HIV prevalence were positive for a variety of socioeconomic groups (urban residence, province of residence, level of education, ethnicity). In a multivariate analysis, based on the 2013 DHS survey, circumcised men were found to have the same level of infection as uncircumcised men, after controlling for age, sexual behaviour and socioeconomic status. Lastly, circumcised men tended to have somewhat riskier sexual behaviour than uncircumcised men. This study, based on large representative samples of the Zambian population, questions the current strategy of mass circumcision campaigns in southern and eastern Africa.

Objective To investigate whether children with concurrent wasting and stunting require therapeutic feeding and to better understand whether multiple diagnostic criteria are needed to identify children with a high risk of death and in need of treatment. Design Community-based cohort study, following 5751 children through time. Each child was visited up to four times at 6-month intervals. Anthropometric measurements were taken at each visit. Survival was monitored using a demographic surveillance system operating in the study villages. Setting Niakhar, a rural area of the Fatick region of central Senegal. Participants Children aged 6–59 months living in thirty villages in the study area. Results Weight-for-age Z-score (WAZ) and mid-upper arm circumference (MUAC) were independently associated with near-term mortality. The lowest WAZ threshold that, in combination with MUAC, detected all deaths associated with severe wasting or concurrent wasting and stunting was WAZ

The study covers the first 6 months of the coronavirus disease 2019 (COVID-19) epidemics in 56 African countries (February 2020-August 2020). It links epidemiological parameters (incidence, case fatality) with demographic parameters (population density, urbanization, population concentration, fertility, mortality, and age structure), with economic parameters (gross domestic product [GDP] per capita, air transport), and with public health parameters (medical density). Epidemiological data are cases and deaths reported to the World Health Organization, and other variables come from databases of the United Nations agencies. Results show that COVID-19 spread fairly rapidly in Africa, although slower than in the rest of the world: In 3 months, all countries were affected, and in 6 months, approximately 1.1 million people (0.1% of the population) were diagnosed positive for COVID-19. The dynamics of the epidemic were fairly regular between April and July, with a net reproduction rate R0 = 1.35, but tended to slow down afterward, when R0 fell below 1.0 at the end of July. Differences in incidence were very large between countries and were correlated primarily with population density and urbanization, and to a lesser extent, with GDP per capita and population age structure. Differences in case fatality were smaller and correlated primarily with mortality level. Overall, Africa appeared very heterogeneous, with some countries severely affected while others very little.

The study analyzes the links between family planning programs, contraceptive preva-lence and fertility trends in sub-Saharan Africa. It is based on case studies of countries with demographic surveys. The study reveals a variety of situations. Some countries have completed their fertility transition, while others have reduced their fertility level rap- idly in urban areas, but less so in rural areas. In some countries, fertility remained very high, or declined very little, in rural areas, when population policies and family planning programs remained insufficient or almost non-existent. The role of family planning pro- grams in fertility decline is highlighted by contrasting countries with similar characteris-tics, one of which experiencing a sharp drop in fertility, while the other one is showing a small decline or no decline at all. In each case, the political, economic, and social context is presented in order to explain the differences between family planning programs and their outcomes. These case studies make it possible to draw conclusions about the condi-tions of fertility control in African countries.

The study describes the patterns of concurrent wasting and stunting (WaSt) among children age 6–59 months living in the 1980s in Niakhar a rural area of Senegal under demographic surveillance. Wasting and stunting were defined by z scores lower than -2 in weight for height and height for age. Both conditions were found to be highly prevalent wasting more so before age 30 months stunting more so after age 30 months. As a result concurrent WaSt peaked around age 18 months and its prevalence (6.2%) was primarily the product of the two conditions with an interaction term of 1.57 (p < 10-6). The interaction was due to the correlation between both conditions (more stunting if wasted more wasting if stunted). Before age 30 months boys were more likely to be concurrently wasted and stunted than girls (RR = 1.61) but the sex difference disappeared after 30 months of age. The excess susceptibility of younger boys could not be explained by muscle mass or fat mass measured by arm or muscle circumference triceps or subscapular skinfold. Concurrent WaSt was a strong risk factor for child mortality and its effect was the product of the independent effect of each component with no significant interaction. Key messages: 1) Prevalence of concurrent wasting and stunting (WaSt) among under-five children is the product of independent wasting and stunting plus an interaction term of 57%. Prevalence of WaSt peaks around age 18 months; 2) Prevalence of WaSt is about 50% higher among boys than among girls before age 30 months largely because their higher susceptibility to stunting but not higher thereafter; and 3) Excess mortality associated with WaSt is the product of that associated with wasting and that associated with stunting.

Department ofPaediatrics, Catholic University of Leuven, Leuven, BelgiumSubmitted 16 August 2008: Accepted 1 December 2008: First published online 3 March 2009AbstractObjective: The present study aimed to compare two situations of endemicmalnutrition among ,5-year-old African children and to estimate the incidence,the duration and the case fatality of severe wasting episodes.Design: Secondary analysis of longitudinal studies, conducted several years ago,which allowed incidence and duration to be calculated from transition rates. Thefirst site was Niakhar in Senegal, an area under demographic surveillance, wherewe followed a cohort of children in 1983–5. The second site was Bwamanda inthe Democratic Republic of Congo, where we followed a cohort of children in1989–92. Both studies enrolled about 5000 children, who were followed byroutine visits and systematic anthropometric assessment, every 6 months in thefirst case and every 3 months in the second case.Results: Niakhar had less stunting, more wasting and higher death rates thanBwamanda. Differences in cause-specific mortality included more diarrhoeal dis-eases, more marasmus, but less malaria and severe anaemia in Niakhar. Severewasting had a higher incidence, a higher prevalence and a more marked age profilein Niakhar. However, despite the differences, the estimated mean durations ofepisodes of severe wasting, calculated by multi-state life table, were similar in thetwo studies (7?5 months). Noteworthy were the differences in the prevalence andincidence of severe wasting depending on the anthropometric indicator (weight-for-height Z-score #–3.0 or mid upper-arm circumference ,110mm) and thereference system (National Center for Health Statistics 1977, Centers for DiseaseControl and Prevention 2000 or Multicentre Growth Reference Study 2006).Conclusions: Severe wasting appeared as one of the leading cause of deathamong under-fives: it had a high incidence (about 2% per child-semester), longduration of episodes and high case fatality rates (6 to 12%).KeywordsUnder-fivesAnthropometrySevere wastingMalnutritionWeight-for-heightMid upper-arm circumferenceMortalityIncidenceCase fatalityMulti-state life tablesSub-Saharan AfricaNiakharBwamandaSevere wasting, defined as very low weight-for-height oras very small arm circumference for age, is frequentamong under-fives in developing countries, and is anindication for urgent medical attention and intensivenutritional rehabilitation. Severe wasting has drawn theattention of nutritionists for a long time and, despite overallimprovements in nutritional status, has become again asubject of research because treatment for severe wasting hasimproved dramatically and become increasingly efficient inrecent years

The study documents cases of extremely high fertility in sub-Saharan Africa. The DHS surveys were used for the analysis, with straightforward calculations of period and cohort fertility. Two case studies were further analysed: Kenya (1965-69) and Niger (1982-86). In both cases, total fertility in rural areas reached 9 children per woman, as high as among the Hutterites of North-America (1921-1940). However, the complete family size never exceeded 8.0 children per woman in Kenya (cohorts 1939-1946) and 8.2 children per woman in Niger (cohorts 1960-1967). Compared with the Hutterites, in both African countries the age pattern of fertility was earlier and with a lower mode, age at marriage was earlier, birth intervals were longer because of long breastfeeding, and secondary infertility was more frequent after the 5th birth. Other proximate determinants of fertility appeared similar in the three populations, with the probable exception of health and nutritional status. Implications for modelling are discussed.

SummaryThis study analysed sex ratios at birth (defined as the number of male births per 100 female births) using data on children ever-born from three censuses conducted in Ethiopia in 1984, 1994 and 2007. The results showed very high values by any standard, with an average of 108.4 for a sample of some 8.2 million births, with somewhat lower values in urban areas. Analysis of socioeconomic correlates revealed that the sex ratio varied very much by household wealth, from about 110 for very poor women to about 102 for wealthier women. The high value of the sex ratio at birth in Ethiopia could be explained by poverty, used as a proxy for poor nutritional status. In multivariate analysis, the effects of living in urban areas and of maternal education were less important than household wealth. Among the many ethno-linguistic groups, the Nilotic family had higher sex ratios than other groups. The results were confirmed using data from DHS surveys conducted in the country, and by the analysis of children still living at time of census.

The study uses data from eight censuses conducted between 1970 and 2011 to reconstruct long term trends in terminal celibacy in South Africa. The cohort analysis covers those born between 1870 and 1971. Results show a quasi-stable prevalence of terminal celibacy for cohorts born before 1920, followed by a steep rise. Levels and trends were notably different for the four population groups. Black/Africans had the highest level at endpoint (50% celibate), despite lower levels at onset, followed by Coloured (34%). Indian/Asian had the lowest level at endpoint (14%). White/European had highest levels at onset, and intermediate values at endpoint (17%). Differences were large by ethnicity, Zulu and Swazi having the highest prevalence of terminal celibacy (60%). Correlations with development were complex, with higher values among persons with lower education, and those living in urban areas, and lower values among those who were employed. Overall, cultural factors dominated the rise in terminal celibacy in South Africa.

Demographic surveys and censuses often record pregnancy-related deaths, defined as those occurring during the maternal risk period (pregnancy, delivery, and six weeks postpartum), but do not include cause of death. This study presents a method for estimating obstetric mortality from pregnancy-related deaths data. Calculations are based on multiple-decrement life tables, and data needed are simply age-specific fertility and mortality rates that are commonly available in Demographic and Health Survey (DHS) or census data, and an estimate of the relative risk of death from nonobstetric causes during the maternal risk period. The method is tested on 59 DHS surveys from Africa. Results show that, on average, less than half of the pregnancy-related deaths are attributable to obstetric causes. This proportion varies with the level of mortality and fertility, and in particular with the prevalence of HIV in the population.

The World Health Organization and UNICEF define non-oedematous severe acute malnutrition (SAM) either by a mid-upper arm circumference (MUAC) less than 115 mm or by a weight-for-height z-score (WHZ) less than -3. The objective of this study was to assess whether there was any benefit to identify malnourished children with a high risk of death to combine these two diagnostic criteria. Data of a longitudinal study examining the relationship between anthropometry and mortality in rural Senegal and predating the development of community-based management of SAM were used for this study. First, the receiver operating characteristic (ROC) curves of MUAC and of WHZ to predict mortality were drawn, and then the points corresponding to WHZ less than -3 and/or MUAC less than 115 mm were positioned in relation to these curves. MUAC had the highest ROC curve, which indicates that it identifies high-risk children better than WHZ. Both points representing WHZ less than -3 and/or MUAC less than 115 mm were below the MUAC ROC curve. It is concluded that to identify high-risk malnourished children, there is no benefit in using both WHZ less than -3 and/or MUAC less than 115 mm, and that using MUAC alone is preferable.

SummaryIn this study, sex ratios at birth (male/female births) were found to vary according to family composition. Using Demographic and Health Survey (DHS) maternity histories from sub-Saharan Africa, the study shows that the sex ratio at birth increases with the number of previous male births and decreases with the number of previous female births. For families with only males, the sex ratio increases from 1·046 for the first birth to 1·083 for the 8th birth. For families with only females, the sex ratio decreases from 1·046 for the first birth to 0·942 for the 8th birth. The differences were highly significant when tested with a linear logistic model (p=0·018 for males; p=1·85✕10−11 for females). The effect was not symmetrical, and was found to be significantly stronger for females. These effects could be reproduced assuming a strong heterogeneity between couples. The distribution of sex ratios was fitted with an asymmetrical log-gamma function, which revealed a wide range of variation in the sex ratio between 0·50 and 1·30, and a peak around 1·14. The results and their implications are discussed in the light of former findings in France and in the United States of America.

The study analyses the profile and the behavior of male clients of female commercial sex workers (CSW's) in Zambia. According to the Zambia 2001 DHS survey, among the 1730 men sexually active during the past year, the pro- portion who used the services of CSW's in the 12 months prior to the survey was 13.2%. This proportion varied very much with age and marital status. Most clients of CSW's were unmarried men. Several demographic, socioeconomic, and personal factors were identified, which effect differed according to marital status. Using the services of CSW's appears as a very heterogeneous behavior, with major differences according to age, marital status, socioeconomic status, and per- sonal attitudes. A multiple correspondence analysis revealed that attitudes (drinking, smoking, wife-beating) were or- thogonal to age, marital status and socioeconomic status. The frequency of visits to CSW's was fitted with a Poisson model. On the average, clients visited CSW's 3.8 times a year.

This paper examines the complex relationship between male circumcision and HIV prevalence and incidence in sub-Saharan African countries that have generalised epidemics. In South Africa, the mean yearly HIV incidence and an estimate of the net reproduction rate of the epidemic (R0) (in this case, the ratio of the number of HIV-infected persons between 1994 and 2004 to the number of persons infected in 1994 from which they were presumed to have become infected) were computed from antenatal clinic data for the period 1994–2004, and then compared, by province, to prevailing levels of male circumcision (high, medium and low). In South Africa, mean yearly HIV incidence and net reproduction rate of the epidemic were not lower in provinces with higher levels of male circumcision. For thirteen other countries where Demographic and Health Survey data were available, male HIV prevalence in circumcised and non-circumcised groups was compared. A meta-analysis of that data, contrasting male HIV seroprevalence according to circumcision status, showed no difference between the two groups (combined risk ratio [RR] = 0.99, 95% CI = 0.94–1.05). Individual case study analysis of eight of those countries showed no significant difference in seroprevalence in circumcised and uncircumcised groups, while two countries (Kenya and Uganda) showed lower HIV prevalence among circumcised groups, and three countries (Cameroon, Lesotho and Malawi) showed higher HIV prevalence among circumcised groups. In most countries with a complex ethnic fabric, the relationship between men's circumcision status and HIV seroprevalence was not straightforward, with the exception of the Luo in Kenya and a few groups in Uganda. These observations put into question the potential long-term effect of voluntary circumcision programmes in countries with generalised HIV epidemics. Keywords: demography; epidemiology; HIV infection; household surveys; meta-analysis; prevention and control; quantitative data; statistical analysisAfrican Journal of AIDS Research 2008, 7(1): 1–8