Early childhood mortality--a rural study

The present study was conducted in 9 villages of Rural Health Training Centre, Jawan, Aligarh, India, having 1792 registered families. The infant mortality rate was 79.3 per 1000 live births. Higher mortality in children between 1-2 years (29.6/1000) in comparison to 2-5 years (16.2/1000) reflected the higher vulnerability of children below 2 years. Diarrhoea (21.2%) and neonatal factors (21.2%) were the major cause of infant mortality followed by pneumonia (18.2%) and tetanus (15.1%). Diarrhoea (32.2%), pneumonia (22.6%) and malnutrition (12.9%) were the major killers in children between 1-5 years. Mortality in females was higher than males in infancy. Risk factors associated with infant mortality included extremes of maternal age (< 20+ > 35 years) primipara or multipara and illiterate mothers.

Cell-mediated immune deficiency and malnutrition are independent risk factors for persistent diarrhea in Bangladeshi children

A community-based longitudinal study was carried out at Matlab, Bangladesh, to investigate the magnitude of the problem of persistent diarrhea; 705 children aged < 5 y were followed, yielding 7300 child-months of observation in 1 y. Morbidity data were collected every fourth day by home visit, anthropometric status was determined monthly, and cell-mediated immune status was assessed every 3 mo. The incidence of persistent diarrhea was 34 episodes per 100 child-years; rates were highest in infancy and declined through the remainder of childhood. In a logistic-regression model, weight-for-height status and immune status were significant predictors of persistent diarrhea. Compared with those at zero Z score, children with weight-for-height at -2 would have a 3.5 times increased risk of persistent diarrhea. Compared with immunocompetent children, immunodeficient children had about twice the risk of developing persistent diarrhea. Thus, nutritional status and cell-mediated immune status were important independent risk factors for persistent diarrhea.

Acute toxicity of vitamin A given with vaccines in infancy

A double-blind, randomised, placebo-controlled trial was conducted to evaluate the safety and toxicity of vitamin A supplementation within the Expanded Programme on Immunisation (EPI) in rural Bangladesh. 191 infants received 3 doses of either 50,000 IU of vitamin A or placebo at about 1.5, 2.5, and 3.5 months and were examined on days 1, 2, 3, and 8 after supplementation. 11 infants (11.5%) supplemented with vitamin A had episodes of bulging of the fontanelle as opposed to 1 (1%) in the placebo group. 16 of the 17 events occurred in the vitamin A supplemented group. No other side effects were noted. There was a tendency towards a cumulative effect of toxicity with increasing doses.

Gender and age differentials in risk factors for childhood malnutrition in Bangladesh

A case-control study of risk factors of clinical marasmus was undertaken to determine which factors differed according to gender and age groups. Case patients were children whose mid-upper arm circumference measured less than 110 mm and control subjects were children matched for age and sex with an arm circumference more than 120 mm. Between June 1988 and June 1989, 164 such pairs of children aged 1 to 4 years were studied. The effect of various demographic, socioeconomic, environmental, and health factors was investigated in a multivariate analysis using conditional logistic regression. Results showed an increased risk of marasmus among children with siblings under 5 years old. This increased risk was observed irrespective of gender or age. Children who consumed formula foods also had an increased risk of marasmus. Again, this elevated risk was maintained for boys and girls. Overall, higher maternal education was associated with a reduced risk of marasmus; however, this was only statistically significant for boys and for children 18 months or older. Religion was also associated with marasmus but only in older children (> or = 18 months). These results indicate that better strategic planning is necessary to formulate effective interventions to reduce severe malnutrition, particularly in societies where strong age- and sex-preferential behavior exists.

Risk factors for clinical marasmus: a case-control study of Bangladeshi children

A case-control study of risk factors of clinical marasmus was undertaken to guide intervention efforts in rural Bangladesh. Cases were children whose mid-upper arm circumference measured < 110 mm and controls were children matched for age and sex with arm circumference > 120 mm. Between June 1988 and June 1989, 164 such pairs of children aged 1-4 years were studied. The effects of various demographic, socioeconomic, environmental, and health factors, reported by mothers, were investigated in a multivariate analysis using conditional logistic regression. Results showed an increased risk of marasmus among children from families with other children under 5 years of age (odds ratio [OR] = 2.51; 95% confidence interval [CI]: 1.33-4.74), and children who consumed formula foods (OR = 16.41, 95% CI: 3.39-79.36). Higher maternal education was associated with reduced risk of marasmus, compared with no education, the OR for < 5 years of schooling = 0.57, 95% CI: 0.23-1.41; OR for > or = 5 years of schooling = 0.34, 95% CI: 0.15-0.76. The strong association of childhood marasmus with mother's education and child spacing supports the notion that non-nutritional factors should be essential components of efforts to reduce severe malnutrition in Bangladesh.

Malnutrition, cell-mediated immune deficiency, and diarrhea: a community-based longitudinal study in rural Bangladeshi children

A community-based longitudinal study was conducted in Matlab, a rural area of Bangladesh, from May 1988 to April 1989 to examine the associations among malnutrition, cell-mediated immune deficiency, and the incidence of diarrhea in children under age 5 years. A cohort of 705 children was followed for a year; illnesses were ascertained every fourth day by home visits, anthropometric status was evaluated monthly, and cell-mediated immune status was assessed by a multiple antigen skin test at baseline and every 3 months. The diarrhea incidence rate was 4.6 episodes per year. Approximately three quarters of the children were below -2 z score weight for age and height for age, and about a third were below -2 z score weight for height. There was a modest association between undernutrition and the incidence of diarrhea. About 10-20% of the study children were anergic, and these children experienced a 50% increased incidence of diarrhea compared with their immunocompetent counterparts. This association persisted after controlling for the effects of age, nutritional status, socioeconomic status, and history of diarrhea in the previous 3 months. Malnutrition and cell-mediated immune deficiency were important independent risk factors for the occurrence of diarrhea and must both be considered in the design of interventions for the control of this condition.

Rotavirus diarrhea in Bangladeshi children: correlation of disease severity with serotypes

To improve the understanding of the relative importance of serotypes of rotavirus in dehydrating diarrhea, we examined the correlation of clinical characteristics and disease severity with serotype in 2,441 diarrheal episodes among children younger than 2 years of age in rural Bangladesh. Of 764 rotavirus-associated episodes, a single G type (serotype 1, 2, 3, or 4) was determined by oligonucleotide probe in 485 (63%), while 233 episodes were nontypeable. Episodes with G types 2 and 3 were associated with more-severe dehydration than episodes associated with G type 1 or 4 or with nontypeable rotavirus. Episodes did not differ by G type in prevalence of vomiting, copious diarrhea, fever, abdominal pain, or length of treatment center stay. Rotavirus reinfections were detected in seven children, with homologous reinfection (G type 2) in one. Twelve children with diarrhea who died had rotavirus detected in stool specimens within 30 days of death. Children who died were more likely to be malnourished than were surviving children with rotavirus diarrhea. Of 40 specimens tested by polymerase chain reaction, 29 (72.5%) were P type 1, 9 (22.5%) were P type 2, 1 (2.5%) was P type 3, and 1 (2.5%) was nontypeable. One severely symptomatic diarrheal episode was associated with P type 3 rotavirus, a serotype usually found in asymptomatic nursery infections. Although G types 2 and 3 were associated with more-severe dehydration than other serotypes, the differences do not appear to be of major clinical importance. Effective vaccines should protect against all four major G types.

Evidence that inactivated oral cholera vaccines both prevent and mitigate Vibrio cholerae O1 infections in a cholera-endemic area

In a randomized, placebo-controlled field trial of B subunit-killed whole cell (BS-WC) and killed whole cell only (WC) inactivated oral cholera vaccines in rural Bangladesh, active surveillance of selected neighborhoods during the first year after vaccination identified 127 Vibrio cholerae O1 infections among 3285 three-dose recipients. For each vaccine, protective efficacy was greater against symptomatic (57%, P < .05 for BS-WC; 58%, P < .05 for WC) than against asymptomatic infections (46%, P < .05 for BS-WC; 32%, P = .09 for WC), and protection against each grade of infection was demonstrable for both the classical and El Tor biotypes. Although vaccine protection against symptomatic infections was evident in both young children and older persons, only persons vaccinated at age > 5 years were protected against asymptomatic infections. These results suggest that the inactivated oral vaccines acted both to protect against intestinal colonization by V. cholerae O1 and to interrupt the pathogenic sequence of established infections.

Enteropathogens associated with acute and persistent diarrhea in Bangladeshi children less than 5 years of age

A longitudinal study of diarrhea was carried out from May 1988 to April 1989 by household surveillance of 705 children less than 5 years old in rural Bangladesh. Stool samples were examined for enteric pathogens at the beginning of each diarrheal episode. For persistent episodes, stool examination was repeated on days 15-17 of the illness. For each case of persistent diarrhea, stool samples from age-matched acute diarrheal and healthy controls were examined. Compared with healthy controls, cases of diarrhea were associated with Shigella species (P = .07) and rotavirus (P less than .05). Diffusely adherent Escherichia coli (P less than .05) and cryptosporidia (P = .07) were the only enteropathogens associated with persistent diarrhea in comparison with acute diarrhea. No more than 15% of children had the same class of pathogen identified from stool on both days 1-3 and days 15-17, indicating that persistent infection was uncommon. However, a different enteropathogen was frequently found on days 15-17, suggesting that sequential infection may be a cause of persistent diarrhea.

Persistent diarrhea as a cause of childhood mortality in rural Bangladesh

To determine the importance of persistent diarrhea in childhood mortality a multiple-step verbal autopsy method was used to study 1934 deaths in Matlab, Bangladesh. We found that most of the deaths from acute watery diarrhea occurred in infancy, whereas the peak of non-watery diarrhea deaths was in children over 12 months of age. Children suffering from persistent diarrhea and malnutrition were at highest risk of dying during their third year of life. Children with infectious diseases have a two to four times higher risk of dying if they are malnourished, and for diarrhea the risk is 17 times as high. Forty-nine percent of the diarrheal deaths were in children with malnutrition associated with persistent diarrhea. These results imply that fluid and dietary management are key aspects in the treatment of diarrhea, particularly for those episodes which persist. We conclude that attempts to reduce diarrhoeal deaths with vertical ORT programmes will not have major impact unless other interventions are directed to the persistent diarrhoea-malnutrition complex.

The risk approach to intervention in severe malnutrition in rural Bangladesh

To determine whether clinical marasmus occurs in small groups of children from easily recognizable high-risk households, the authors conducted a case-control study to identify risk indicators that may be used in targeted interventions. Cases were children whose mid-upper arm circumference measured less than 110 mm, and controls were children matched for age and sex with arm circumferences greater than 120 mm. Between June 1988 and June 1989, 164 such pairs of children aged 1-4 years were studied in Matlab, Bangladesh. Conditional logistic regression analysis showed an increased risk of marasmus among children from families with other children under 5 years of age (odds ratio = 2.80, 95% confidence interval 1.56-5.02) and children who consumed formula foods (odds ratio = 18.81, 95% confidence interval 4.15-85). Higher maternal education was associated with reduced risk of marasmus. Further examination of these risk indicators suggests that the resources saved through targeting fewer households will be negated by missing many children with marasmus. The authors conclude that the application of targeted interventions against marasmus, using the risk approach, is unlikely to be efficient.

Nonparticipation as a determinant of adverse health outcomes in a field trial of oral cholera vaccines

The authors estimated the incidence rates of cholera and death between 1985 and 1988 for 32,642 age- and sex-eligible persons who did not participate in a randomized, placebo-controlled field trial of killed oral cholera vaccines in rural Bangladesh. As compared with 20,744 placebo recipients, the relative risk of cholera for all nonparticipants, adjusted for potentially confounding demographic variables, was 1.20 (95% confidence interval (CI) 1.03-1.41); this adjusted relative risk reflected elevated adjusted relative risks in nonparticipants who were medically ineligible (RR = 1.65; 95% CI 1.22-2.22) or refused to participate (RR = 1.19; 95% CI 1.01-1.41), but not in persons absent at the time of vaccination (RR = 1.00; 95% CI 0.78-1.28). The adjusted relative risk of death was also elevated in nonparticipants as compared with placebo recipients (RR = 1.28; 95% CI 1.10-1.48), with the same pattern of adjusted relative risks for different categories of nonparticipants: for ineligible subjects, 2.64 (95% CI 2.12-3.29); for refusers, 1.20 (95% CI 1.02-1.41); and for absentees, 0.95 (95% CI 0.75-1.22). The authors concluded that nonparticipation was associated with clinically cogent adverse health outcomes, but that the magnitude of these associations varied according to the reason for nonparticipation. These findings underscore the caution required in assessing vaccine efficacy with controls who are not vaccinated because of choices made by patients or vaccinators.

Utilization of medically-trained birth attendants in rural Bangladesh

Using case-control methodology, this study compared the characteristics of women who requested medically-trained birth attendants at home with those who did not, in order to identify constraints to service delivery and suggest program changes to increase service utilization in a rural area of Bangladesh. By several different measures, prior contact with medical professionals were much more common among cases than controls, with the greatest differences observed in the frequency of antenatal visits. At least one antenatal visit was the strongest predictor that a woman would call a medically-trained birth attendant, though primiparity, proximity to the provider, previous contact with the clinic, and education (both of the mother and her spouse) were also predictive. Recommendations include increasing contact through antenatal visits, and extending midwife coverage through training and supervision of traditional birth attendants. This study demonstrates the usefulness of case-control methodology in evaluating health care utilization.

Methodological issues in diarrhoeal diseases epidemiology: definition of diarrhoeal episodes

A review of the diarrhoeal disease literature reveals considerable variability in the definition of diarrhoeal episodes. The use of various definitions of diarrhoea and episodes leads to misclassification, affects the estimates of the disease burden in communities and reduces comparability of the findings from different studies. This study is an attempt to validate the definition of diarrhoeal episodes using prospectively collected community-based surveillance data. In comparative validation analyses, three or more loose stools or any number of loose stools containing blood in a 24-hour period seemed to be the best definition of diarrhoea. Three intervening diarrhoea-free days seemed to be the optimum to define a new episode. The implications of using differing definitions and the importance of using a validated definition are discussed.

Antibody responses after immunization with killed oral cholera vaccines during the 1985 vaccine field trial in Bangladesh

Sera collected during the 1985 oral cholera vaccine trial in Matlab, Bangladesh, which demonstrated efficacy of a whole cell combined with cholera B subunit vaccine (WC/BS) and a whole cell only vaccine (WC), were analyzed for antitoxin and vibriocidal antibodies. Before vaccines were given, antitoxin titers were highest in children, especially those with O blood group, whereas vibriocidal titers rose throughout life. Two weeks after three doses of vaccine, geometric mean antitoxin titers were 2.5-4.5 times higher in vaccinees who received the WC/BS vaccine; the vibriocidal titers were 1.3-2.1 times higher in vaccinees who received either vaccine. The titer elevations were relatively brief and were barely detectable 7 months after the third dose even though significant levels of protection persisted greater than or equal to 3 years. Thus, the oral vaccines induced a serum response in this large field trial that was similar to that seen in earlier pilot studies, but the duration of the serum responses was much shorter than the duration of the protection.

Field trial of oral cholera vaccines in Bangladesh: serum vibriocidal and antitoxic antibodies as markers of the risk of cholera

The relationship of serum vibriocidal (VC) and IgG anti-cholera toxin (CT) antibodies to the risk of cholera was evaluated during the first year of follow-up of recipients of three oral doses of B subunit (BS)-whole-cell vaccine, whole-cell vaccine, or Escherichia coli K12 strain placebo in Bangladesh. Acute sera from 121 cholera patients were compared with sera from 2592 contemporaneous community controls. Each doubling of VC titer was associated, on average, with a 22%-47% reduction of cholera risk in the three groups. In contrast, in the two groups that did not receive BS, anti-CT titers were directly associated with cholera and thus served as markers of higher cholera risk. Each vaccine conferred approximately 65% protective efficacy against cholera, but antibody titers did not correlate with vaccine efficacy, indicating that serum VC and anti-CT antibodies are poor markers of the longitudinal pattern of vaccine efficacy.

Surveillance of shigellosis in rural Bangladesh: a 10 years review

Over a period of 10 years 35,620 patients, admitted from a defined surveillance area, had a rectal swab culture done at a rural diarrhoea treatment centre in Bangladesh. Shigella spp. were isolated from 3,440 (9.7%) cases. Marked year to year variations were observed in isolation rates of Shigella spp. ranging from 5.7% to 16.7%. Sh. flexneri was the predominant isolate between 1978 to 1982 (56%-67%), Sh. dysenteriae type 1 predominated from 1983 to 1985 (45%-50%), and again Sh. flexneri became predominant in 1986 (55%) and 1987 (61%). Shigella were most commonly isolated from children aged 1-4 years followed by children 5-9 years and elderly people aged 45+ years. Sh. flexneri was isolated most frequently during August - January and Sh.dysenteriae type 1 during June to July. The overall case fatality rate in patients with shigellosis was 0.96%. It was 1.10% in children under 5 years of age. Prevalence of multiple antibiotic resistant strains increased over the years and at present most strains are resistant to commonly used antibiotics such as ampicillin and cotrimoxazole. Nalidixic acid is currently the drug of choice for Shigella infection in this area.

Diarrhoea mortality in rural Bangladeshi children

Diarrhoeal mortality and hospital admissions for diarrhoea are described among children under the age of 5 years in a large rural Bangladeshi community during 1986-87. Acute watery (dehydrating) diarrhoea was associated with 11 per cent of all deaths among infants aged 1-11 months and 5 per cent among children aged 1-4 years. Acute non-watery diarrhoea, including bloody dysentery and diarrhoea with mucoid stools, was associated with 16 per cent of all deaths among children aged 1-4 years. In this age group, persistent diarrhoea, particularly when accompanied by recent and/or severe wasting, was associated with 63 per cent of all diarrhoeal deaths and 34 per cent of all deaths. These data suggest that exclusive emphasis on ORT will have little impact on diarrhoea mortality among children in rural Bangladesh. A broader strategy, both preventive and curative, including measles immunization, nutrition education, dietary management of diarrhoea, and the treatment of dysentery in the community, carries a greater potential.

Is acute watery diarrhoea an important cause of morbidity and mortality among rural Bangladeshi children?

To assess the relative importance of acute watery diarrhoea (AWD) and other types of acute diarrhoea as causes of morbidity and mortality among infants and 1-4 years old children, we examined 3 different data sources from the Matlab field project of the International Centre for Diarrhoeal Disease Research, Bangladesh. In infants, prevalence rates for AWD and non-watery diarrhoeas were similar. In children, prevalence of AWD was 1.8 times lower than prevalence of other acute diarrhoeas. In infants, admission rate to a diarrhoea hospital was 4.1 times higher for AWD than for other acute diarrhoeas (P less than 0.001). In children, admission rate was only 1.7 times higher for AWD than for acute diarrhoeas (P less than 0.001). Infant mortality was 1.7 times higher for AWD than for other acute diarrhoeas, but child mortality was 3 times lower for AWD. These data suggest that, while diarrhoeal disease control programmes should give more importance to oral rehydration therapy in infants, field management of the other types of acute diarrhoea should receive more emphasis in children.

A new imprinting material for scanning electron microscopic studies

A new imprinting material, "Thermocool", has been used for preparing negative replicas of plant as well as metal surfaces for SEM study. The technique has wide application and gives very good results.

Host factors in childhood diarrhoea

Host factors play a significant role in children under five who are the worst sufferers of this widespread and global scourge, both in regard to mortality and morbidity. This study deals with some of the host factors in relation to diarrhoea in a rural population. Age was found to have a definite and direct relationship to diarrhoea. Male children were effected more. Poor hygiene, malnutrition and the receipt of supplementary feeds, were found to have a significant association with childhood diarrhoeas.