Showing papers by "International Centre for Diarrhoeal Disease Research, Bangladesh published in 1992"

Enteropathogens Associated with Acute and Persistent Diarrhea in Bangladeshi Children <5 Years of Age

Abstract: 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.

Antimicrobial resistance of Shigella isolates in Bangladesh, 1983-1990: increasing frequency of strains multiply resistant to ampicillin, trimethoprim-sulfamethoxazole, and nalidixic acid.

Abstract: The susceptibility to ampicillin and trimethoprim-sulfamethoxazole (TMP-SMZ) was determined for 15,824 isolates of Shigella obtained from patients attending a treatment center in Dhaka, Bangladesh, from 1983 through 1990 and for 520 isolates obtained during community surveys from 1988 through 1990. Susceptibility to nalidixic acid was determined for isolates obtained after 1985. In 1983 13% of isolates were resistant to ampicillin, 23.5% to TMP-SMZ, and 0.8% to both drugs. By 1990 51.2% of isolates obtained at the Diarrhea Treatment Centre were resistant to ampicillin, 47.7% to TMP-SMZ, and 40.5% to both drugs (for comparison with figures for 1983, P less than .001). Resistance to nalidixic acid increased from 0.8% in 1986 to 20.2% in 1990 (P less than .001). In 1990 71.5% of Shigella dysenteriae type 1 isolates were resistant to ampicillin, 68.5% to TMP-SMZ, 67.7% to both drugs, and 57.9% to nalidixic acid. The resistance pattern of isolates obtained during community surveillance was similar to that of Treatment Centre isolates. In Bangladesh ampicillin and TMP-SMZ are no longer useful for treatment of infection with any species of Shigella, and nalidixic acid is no longer useful for treatment of infections due to S. dysenteriae type 1.

Sharing of virulence-associated properties at the phenotypic and genetic levels between enteropathogenic Escherichia coli and Hafnia alvei.

Abstract: Seven strains of Hafnia alvei isolated from diarrhoeal stools of children resembled enteropathogenic Escherichia coli (EPEC) in that they produced attaching-effacing (AE) lesions in rabbit ileal loops and fluorescent actin staining in infected HEp-2 cells. In addition, a DNA probe from a chromosomal gene required by EPEC to produce AE lesions, hybridised to chromosomal DNA from all seven H. alvei strains. These findings indicate that there is a sharing of virulence-associated properties at the phenotypic and genetic levels by H. alvei and EPEC. H. alvei strains with these properties should be considered diarrhoeagenic.

Treatment of Shigellosis: III. Comparison of One- or Two-Dose Ciprofloxacin with Standard 5-Day Therapy: A Randomized, Blinded Trial

Abstract: OBJECTIVE To determine whether a single dose, or 2 doses, of ciprofloxacin are as effective as 5-day, 10-dose therapy for the treatment of shigellosis in adult men who are moderately to severely ill. DESIGN Randomized, double-blind clinical trial. SETTING A diarrhea treatment center in the capital city of a developing country, Bangladesh. PATIENTS A total of 128 adult men with dysentery of less than 96 hours duration. All had Shigella organisms isolated from a culture of stool. INTERVENTIONS Patients were randomly assigned to receive either a single 1-gram dose of ciprofloxacin at admission to the study (single-dose group; n = 40), a 1-gram dose of ciprofloxacin at admission and 24 hours later (2-dose group; n = 43), or 500 mg of ciprofloxacin every 12 hours for 5 days (10 dose group; n = 35). All patients were hospitalized for 6 days. MEASUREMENTS Stools were collected individually; their character and consistency were recorded and cultured daily. A physical examination and recording of symptoms were done daily, and the temperature was measured every 4 hours. Therapy was considered to have failed in patients who did not have improvement in the signs and symptoms of dysentery after 72 hours of therapy or in patients who on study day 5 had more than nine stools, or more than two watery stools, or were febrile. RESULTS There were no treatment failures in the 78 patients infected with species of Shigella other than Shigella dysenteriae type 1. Among the 40 patients infected with S. dysenteriae type 1, treatment failed in 4 of the 10 patients who received single-dose therapy, 2 of the 15 patients who received 2-dose therapy, and none of the 15 patients who received 10-dose therapy (P = 0.017, single-dose therapy group compared with 10-dose group; P = 0.15 for the single-dose group compared with the 2-dose group; P > 0.2 for the 2-dose group compared with the 10-dose group). CONCLUSIONS A single 1-gram dose of ciprofloxacin is effective therapy for patients infected with species of Shigella other than S. dysenteriae type 1. Single-dose therapy is inferior to 10-dose therapy for treating patients infected with S. dysenteriae type 1.

Detection of Shigella dysenteriae type 1 and Shigella flexneri in feces by immunomagnetic isolation and polymerase chain reaction.

Abstract: A combination of immunomagnetic separation (IMS) and a polymerase chain reaction (PCR) procedure was used for direct isolation and identification of Shigella dysenteriae type 1 and Shigella flexneri from feces. Immunomagnetic particles were coated with monoclonal antibody MASFB, which is specific for a common epitope of the O polysaccharides of S. dysenteriae type 1 and S. flexneri. Bacteria bound to the beads were boiled in water, and target DNA was amplified with a primer pair specific for a gene coded on the invasion-associated locus (ial) of the large virulence plasmid of all four Shigella spp. and enteroinvasive strains of Escherichia coli. A 320-bp DNA fragment was generated and detected by an alkaline phosphatase-conjugated probe. Nonviable cells were also captured and detected by this technique. The method is simple and fast (7 h) and has a detection limit of ca. 10 Shigella organisms per g in fecal samples. The combined IMS-PCR assay correctly identified all 57 samples carrying S. dysenteriae type 1 and 68 samples carrying S. flexneri from 238 fecal specimens and also permitted detection of 17 samples carrying Shigella spp. from 113 specimens from diarrheal patients in whom shigellae were not detected by conventional culture.

Cholera epidemics in Bangladesh: 1985-1991.

Abstract: In 1991, a major epidemic of diarrhoea broke out in Bangladesh. To estimate the extent of cholera during diarrhoea epidemics and to focus on the public health issues related to cholera in Bangladesh, we have used the government figures of the 1991 epidemic and data from our own experience of epidemic interventions in nearly 400 rural upazilas (sub-district) between 1985 and 1989 and in 1991. Our data showed that V. cholerae 01 was the most frequently (40%) isolated enteropathogen during the epidemics. The disease is widely distributed in the country. Only 24% of the total 1,648 laboratory confirmed cholera patients were below 5 years of age, and children below 2 years of age accounted for only 10% of the total. Access difficulty to medical care and absence of a reliable surveillance were thought to be the constraints to early detection and appropriate intervention, thus, there were more deaths during the epidemics. We have shown that a high proportion (59%) of cholera patients during their illness in the rural areas were not visited by the government surveillance staff and that most (80%) were treated at home. Access to treatment by qualified physicians was limited to 23% of the patients, whereas a large proportion of the patients were treated by the unqualified rural practitioners (68%), and the others (9%) had no access to any health care providers. Our experience also indicated a higher case fatality ratio (14%) prior to intervention by qualified physicians during epidemics and an overall fatality ratio of 4%, despite the significant reduction (less than 1%) achieved by the intervention. Cholera is highly epidemic in Bangladesh.(ABSTRACT TRUNCATED AT 250 WORDS)

In vitro antibacterial activity of the volatile oil of Nigella sativa seeds against multiple drug‐resistant isolates of Shigella spp. and isolates of Vibrio cholerae and Escherichia coli

Abstract: The antibacterial activity of the volatile oil of Nigella sativa seeds was studied against 37 isolates of Shigella dysenteriae 1, Shigella flexneri, Shigella sonnei and Shigella boydii and 10 strains of Vibrio cholerae and Escherichia coli. Most of the strains were clinically resistant to ampicillin, co-trimoxazole and tetracycline. All the strains tested showed promising sensitivity to the volatile oil. The minimum inhibitory concentration (MIC) of the volatile oil for Shigella, Vibrio and Escherichia strains tested was between 50–400 μg/mL.

Impact on mortality of a community-based programme to control acute lower respiratory tract infections.

Abstract: Acute lower respiratory tract infections (ALRIs) are a major cause of death among young children in developing countries. A targeted programme designed to treat children with ALRI was implemented in 1988 in a primary health care project in rural Bangladesh. In the 2 years preceding the introduction of the programme (1986-87), non-ALRI-specific health services were provided, including promotion of oral rehydration therapy, family planning, immunization of children and mothers, distribution of vitamin A, referral of severely sick children to field clinics, and nutritional rehabilitation of malnourished children. The targeted ALRI programme, which was in place in 1988-89, was based on systematic ALRI case detection and management by community health workers, who were linked to a referral system for medical support. These two levels of intervention have been evaluated by comparing the ALRI-specific mortality in the programme area and a neighbouring control area during the two periods. During the first phase (1986-87), the ALRI mortality among under-5-year-olds was 28% lower in the intervention than in the comparison area (P less than 0.01). During the second phase (1988-89), the ALRI mortality was 32% lower in the intervention area than during the preceding phase, while there was no significant difference for the comparison area. These findings suggest that in the study region the combination of specific and nonspecific interventions can reduce ALRI mortality by as much as 50% and the overall mortality among under-5-year-olds by as much as 30%.

Community-based evaluation of the effect of breast-feeding on the risk of microbiologically confirmed or clinically presumptive shigellosis in Bangladeshi children.

Abstract: To assess the association between breast-feeding and the risk of microbiologically confirmed or clinically presumptive shigellosis, the authors performed a case-control analysis of Bangladeshi children younger than 3 years of age who were followed up for 1 month after exposure to Shigella in their residential neighborhoods. Two hundred sixty-nine cases with culture-confirmed shigellosis (n = 119) or clinically presumptive shigellosis (culture-negative dysentery, n = 150) were compared with 819 controls without Shigella diarrhea or other invasive diarrheal illnesses. The odds ratio relating breast-feeding to confirmed or presumptive shigellosis, adjusted for potentially confounding variables, was 0.48 (95% confidence interval = 0.32 to 0.72; P less than .001), suggesting a substantial protective effect. The protective association decreased with age but was still significant during the third year of life; appeared to be directly related to the degree of stunting; and was equivalent for confirmed and presumptive shigellosis. Notably, the protective association remained substantial against episodes due to Shigella which were resistant to at least one of the antibiotics customarily used for treatment of Shigella diarrhea (age-adjusted odds ratio = 0.40; 95% confidence interval = 0.22 to 0.74; P less than .01). These data suggest that breast-feeding confers a high level of protection against shigellosis throughout the first 3 years of life, especially among nutritionally compromised children, and thereby underscore the importance of promotion of breast-feeding as a central component of Shigella control programs in less developed settings.

Persistent diarrhea as a cause of childhood mortality in rural Bangladesh.

Abstract: To determine the importance of persistent diarrhea in childhood mortality a multi-step verbal autopsy method was used to study 1934 deaths in Matlab Bangladesh. The authors found that most of the deaths from acute watery diarrhea occurred in infancy whereas the peak of nonwatery 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 infections diseases have a 2 to 4 times higher risk of dying if they are malnourished and for diarrhea the risk is 17 times as high. 49% 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. The authors conclude that attempts to reduce diarrheal deaths with vertical ORT programs will not have a major impact unless other interventions are directed to the persistent diarrhea-malnutrition complex. (authors)

Pathogenesis of Providencia alcalifaciens-induced diarrhea.

Abstract: Providencia alcalifaciens is a member of the family Enterobacteriaceae. There are reports that P. alcalifaciens can cause diarrhea, but the mechanism(s) by which it causes diarrhea is known. We studied P. alcalifaciens isolated from a child and two adults with diarrhea for enteropathogenicity. The three isolates did not exhibit any characteristic adherence to cultured HEp-2 cell monolayers, and they did not produce enterotoxins, cytotoxins, or keratoconjunctivitis in the Sereny test. Two isolates invaded cultured HEp-2 cell monolayers, producing localized bacterial clusters and actin condensation. The pattern of actin condensation was different from that produced by enteropathogenic Escherichia coli but similar to that produced by Shigella flexneri. Invasion and actin condensation were poor for the third isolate. Histology of adult rabbit small intestinal loops inoculated with all three isolates revealed bacterial attachment to, penetration of, and microulcer formation on the surface epithelium and hyperemia, edema, and polymorphonuclear cell infiltration of lamina propria. All the isolates produced diarrhea in rabbits with removable intestinal ties, and some of these rabbits developed hindlimb paralysis. Intestinal histology of the rabbits with removable intestinal ties which developed diarrhea showed changes similar to that in adult rabbits on which ileal loop assays had been performed. Transmission electron microscopy of intestinal tissues also confirmed tissue penetration by the isolates. Nerve tissue histology of two rabbits that developed hindlimb paralysis showed focal mononuclear cell infiltration around peripheral nerve sheaths. It is concluded that some strains of P. alcalifaciens are enteropathogenic and that they cause diarrhea by invading the intestinal mucosal epithelium. However, the relevance to human disease of the hindlimb paralysis observed in this animal model is not clear. Images

Epidemiological and clinical characteristics of acute and persistent diarrhoea in rural Bangladeshi children

Abstract: A community-based longitudinal study of acute and persistent diarrhoea in 705 children less than five years old was carried out for a year in a rural area of Bangladesh. Diarrhoea morbidity data were collected from each study child every fourth day by home visit. Clinical features of diarrhoeal episodes and diarrhoeal management information were documented. The overall diarrhoeal incidence rate in the study children was 4.6 episodes per child per year. The incidence of persistent diarrhoea was 34/100 child-years. Persistent diarrhoea was positively associated with young age and more severe illness, characterized by the presence of clinical dehydration or blood in the stool in the first week. Use of ORT in the first week was positively associated and use of an antibiotic was negatively associated with the occurrence of persistent diarrhoea. Reduced breast-feeding and consumption of cow's milk at some time during the episode were also positively associated with persistence. This would suggest that appropriate fluid and dietary management for all episodes should be the goal. Children with more severe initial illness characterized by the presence of blood in the stool or clinical dehydration should have more careful follow-up to identify persistent episodes and adverse nutritional effects. Breastfeeding should be continued during acute diarrhoea, but the role of ORT, antibiotics and cow's milk deserves further investigation.

Development and evaluation of a rapid, simple, sensitive, monoclonal antibody-based co-agglutination test for direct detection of Vibrio cholerae 01

Abstract: Cholera epidemics caused by Vibrio cholerae 01 continue to represent a major public health concern in many developing countries. A rapid and simple test kit for the detection of V. cholerae 01 has been developed. The kit, CholeraScreenTM is a monoclonal antibody-based, co-agglutination test and is used directly with stool specimens. It does not include culturing the specimen and is performed without the need for sophisticated laboratory equipment. Specificity of the test was demonstrated, using 118 reference cultures, to which cross-reactions were not observed. Preliminary results of field trials carried out in Guatemala and Bangladesh demonstrated that the test is equally sensitive as conventional culture methods in detecting V. cholerae and, in many cases, more sensitive. The CholeraScreenTM test is simple, specific, and does not require culturing procedures, making it suitable for direct detection of cells of V. cholerae in clinical specimens, even in the field. Also, the test requires less than five minutes to complete.

Seroepidemiologic Evaluation of Antibodies to Rotavirus as Correlates of the Risk of Clinically Significant Rotavirus Diarrhea in Rural Bangladesh

Abstract: A case-control study of children and adult women in Matlab Bangladesh was conducted to see if rotavirus antibodies were associated with less severe clinical diarrhea. Persons attending 3 diarrhea clinics in the area covered by the International Centre for Diarrhoeal Disease Research were tested by ELISA for rotavirus from a fingerstick and cultivated virus were serotyped. 4 2-month long randomized population-based surveys were done between April 1985-April 1986. 7256 subjects were tested;; 219 cases and 477 controls were analyzed. 200 cases were children <2; 72 were severely dehydrated of whom 1 died. The cases were younger than controls and more often male breast-fed Muslim from less educated families. Serum IgG antibodies against rotavirus typically displayed a U-shaped curve with higher titers from birth to a valley at age 4-7 months then a rising curve at older ages. Titers in cases averaged 107 units/ml compared to 417 in controls (p<0.001) lower only in infants <4 months old. Logistic regression analysis demonstrated protective association between anti-rotavirus antibodies and severe dehydration and less severe episodes as well. Even the lowest detectable antibody level 100-199 units/ml was protective but higher titers did not convey added protection until they surpassed 3200 units/ml. It was noted that the observed association between rotavirus immunity and less severe illness does not prove that serum IgG antibodies are protective since intestinal mucosal antibodies are thought to confer resistance against rotavirus.

Contraceptive use in Matlab, Bangladesh: the role of gender preference.

Abstract: Research in several Asian societies has shown that sons are preferred over daughters. This paper explores the effect of sex composition of surviving children on the acceptance and discontinuation of contraception in a sample of 3145 women in Matlab Bangladesh observed over a period of 60 months. Data were analyzed via hazards regression. Strong and significant effects of gender preference were found on contraceptive use. Specifically parents have a strong preference for sons and a moderate preference for daughters. This conclusion is based upon bivariate analysis which revealed contraceptive acceptance and continuation rates to be higher among couples who have at least 1 surviving son than among couples who have no son; rates steadily increased with the number of surviving sons. Acceptance and continuation are lower however among couples who have only sons than among those who have children of both sexes. Parental sex preference is therefore moderated toward a balanced composition of several sons and at least 1 daughter. These preferences pose a significant barrier to fertility regulation in rural Bangladesh. Related literature is reviewed and the study are described.

Seasonality and toxigenicity ofVibrio cholerae non-01 isolated from different components of pond ecosystems of Dhaka City, Bangladesh

Abstract: Diarrhoea due toVibrio cholerae non-01 is common in Bangladesh. Four hundred and eighty samples, including plants, water, phytoplankton and sediment, were collected from five ponds in Dhaka every 15 days for one year.V. cholerae non-01 was isolated from 181 (38%) of the samples. Two peaks were evident: one in April and the other in August/September. Forty-three (23%) of the 181 isolates were examined for toxigenicity and 19% were cytotoxic to Y1 adrenal cells. This study provides evidence of the likely infectious nature of some ponds and may have relevance to the epidemiology of diarrhoea caused byV. cholerae non-01 in Bangladesh.

Gastric emptying of liquid in children suffering from acute rotaviral gastroenteritis.

Abstract: Nausea and vomiting commonly occur in children suffering from rotaviral diarrhoea. Gastric emptying was studied in 10 children (age six to 12 months) suffering from acute diarrhoea caused by rotavirus using a dye dilution double sampling technique. The test meal was 5% dextrose in water and this test was repeated 12 weeks after recovery. The median (range) of the percentages of the liquid meal remaining in the stomach at 5, 10, 20, 40, and 60 minutes after instillation of the meal were 82 (79-90), 70 (61-86), 51 (38-76), 26 (14-53), and 13 (2-35) respectively in the acute stage, whereas after the recovery period the values were 76 (70-79), 58 (49-63), 33 (24-40), 11 (2-26), and 3 (0-7). The differences were statistically significant. The half time of gastric emptying (t1/2) was 19.5 (14-30) minutes in acute stage, and 13.1 (10-15) minutes during follow up (p less than 0.01). Rotaviral gastroenteritis is accompanied by abnormal gastric motor function, as manifested by delayed emptying of a liquid meal.

Nonparticipation as a Determinant of Adverse Health Outcomes in a Field Trial of Oral Cholera Vaccines

Abstract: 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.

A hazard logit model analysis of covariates of childhood mortality in Matlab, Bangladesh.

Abstract: In a prospective study in Matlab, a rural area in Bangladesh, the relationship between a variety of covariates and childhood mortality was examined. Economic status of household, education of mother, sex of the children, health intervention programmes, age of mother, and live birth order of the children were identified as having a statistically significant impact on child survival when the effect of age was controlled. The effects of sex of the children, health programmes, age of mother, and birth order were found to be dependent on the age of the children, but the effect of mother's education was dependent on sex of the children.

Occurrence of resistance to vibriostatic compound 0/129 in Vibrio cholerae 01 isolated from clinical and environmental samples in Bangladesh.

Abstract: Fifty-one Vibrio cholerae 01 strains isolated from 734 natural water and plankton samples and 31 rectal swabs were examined. Of these strains, 32 (62.7%) were found to be resistant to vibriostatic compound 0/129. When antibiograms using the antibiotics ampicillin, tetracycline, chloramphenicol, trimethoprim-sulfamethoxazole, furoxan, and gentamicin were done, it was observed that there was a correlation of sensitivity to 0/129 with selected antibiotics. Only the Ogawa E1 Tor (72% of strains resistant) and Inaba classical (28% of strains resistant) biotypes of V. cholerae 01 showed resistance to 0/129. On the other hand, all Inaba E1 Tor and Ogawa classical strains were susceptible to 0/129. The 32 0/129-resistant and 19 0/129-sensitive isolates of V. cholerae 01 were tested for the presence of plasmid DNA. Only two strains isolated from the environment were found to carry a plasmid, and they were also found to be resistant to 0/129 and gentamicin. Thus, 0/129 resistance, although more common than previously suspected, is concluded not to be plasmid mediated in the strains tested in this study.

Breast feeding and oral rehydration at home during diarrhoea to prevent dehydration.

Abstract: In a case-control study we evaluated the role of maternal behaviour, as reflected in maintenance of breast feeding and the use of oral rehydration therapy (ORT) at home during acute diarrhoea, in preventing dehydration in infants and young children. A systematic 5% sample was taken of all children aged 1-35 months attending the treatment centre of the International Centre for Diarrhoeal Disease Research, Bangladesh, with acute watery diarrhoea of six days or less between August 1988 and September 1989. There were 285 children with moderate or severe dehydration as cases and 728 with no dehydration as controls in the study. In a multivariate analysis using a logistic regression model we showed that withdrawal of breast feeding during diarrhoea was associated with a five times higher risk of dehydration compared with continuation of breast feeding during diarrhoea at home. Lack of ORT with either complete formula or a salt and sugar solution at home was associated with 57% higher risk of dehydration compared with receipt of a reasonable amount of ORT after controlling for several confounders. The confounding variables--that is, lack of maternal education, history of vomiting, high stool frequency, young age and infection with Vibrio cholerae 01--were also shown to be risk factors of dehydration. Health education programmes should promote continued breast feeding and adequate oral rehydration therapy for infants with acute diarrhoea at home.

Indomethacin decreases jejunal fluid secretion in addition to luminal release of prostaglandin E2 in patients with acute cholera.

Abstract: Human cholera is associated with an increased luminal release of prostaglandin E2 (PGE2), but whether inhibition of increased PGE2 synthesis will reduce or control intestinal secretion is uncertain. 'Steady state' perfusions (10 ml/minute) in 12 patients with acute cholera, and repeat perfusions in nine of these patients during the convalescent phase were therefore performed using the triple lumen technique. The proximal jejunum was perfused with isotonic saline containing sodium-sulphobromophthalein as a non-absorbable marker. After intravenous administration of indomethacin (1.0 mg/kg) the jejunal net transfer of fluid and the jejunal flow rate of PGE2 were determined in 30 minute periods for 120 minutes after a 120 minute control period. Indomethacin decreased net fluid secretion (2.1 (0.3-4.2) v 4.5 (2.5-8.4) ml/hour x cm; medians, Q50 ranges, p less than 0.01) and the jejunal flow rate of PGE2 (1.5 (1.2-2.7) v 2.2 (1.4-4.9) ng/minute, p less than 0.05). The results of similar perfusion studies in 22 patients with acute cholera, used to establish the spontaneous time related change in fluid secretion, showed no significant change in net fluid transfer (3.5 (2.2-6.2) to 3.5 (2.6-11.6) ml/hour x cm, p greater than 0.25) over 240 minutes. These data provide further evidence in favour of the hypothesis that prostaglandins have a role in the cholera toxin induced intestinal fluid secretion in man.

Differentiation of Shigella flexneri strains by rRNA gene restriction patterns.

Abstract: We studied the restriction endonuclease cleavage patterns of rRNA genes (ribotypes) of 72 clinical isolates of Shigella flexneri representing eight serotypes to determine whether ribotyping could be used to distinguish S. flexneri strains and to compare the discriminating ability of the method with that of serotyping. By using a cloned Escherichia coli rRNA operon as the probe, Southern blot hybridization of restriction endonuclease-digested total DNA was carried out. Ribotyping of the isolates with each of the five restriction endonucleases BamHI, EcoRI, HindIII, PstI, and SalI generated reproducible restriction patterns. However, HindIII produced the optimum digestion pattern of the rRNA genes and was more useful than the other enzymes used in differentiating strains. Analysis of the 72 isolates showed 11 different HindIII cleavage patterns of their rRNA genes. Four of these HindIII-generated ribotypes could be further differentiated into two to four subribotypes by using PstI. The results indicate that ribotyping has an application for differentiation of S. flexneri strains and can complement serotyping. Definition of strains in terms of both serotype and ribotype may be of greater use in epidemiological studies.

Compliance with diphtheria, tetanus, and pertussis immunisation in Bangladesh: factors identifying high risk groups.

Abstract: OBJECTIVE--To evaluate factors associated with non-compliance with having second vaccination against diphtheria, tetanus, and pertussis in a treatment centre in Dhaka to determine which children were most at risk of not completing immunisation. DESIGN--Cohort study of infants given first dose of the vaccine and followed up six weeks later to ascertain compliance with having second dose. Factors associated with non-compliance were evaluated. SETTING--Dhaka treatment centre of the International Centre for Diarrhoeal Disease Research, Bangladesh. SUBJECTS--136 unimmunised children aged 6 weeks to 23 months who lived within reach of the treatment centre. At time of the six week follow up 16 of the children could not be traced and seven had died. INTERVENTIONS--All children received their first dose of the vaccine. In each case health education workers had informed the mother about the value of immunisation, and she was given clear instructions to bring the child back after four weeks for the second dose. MAIN OUTCOME MEASURE--Rate of non-compliance with advice to return child for second vaccination. RESULTS--46 of 113 children (41%) received the second dose of the vaccine. Factors most closely associated with mothers' failure to comply with the second dose were lack of education and low income. Children whose mothers knew most about immunisation at first interview were more likely to have their second dose. CONCLUSIONS--Preventive health care services such as immunisation are appropriately offered in treatment centres, but compliance among children varies with socioeconomic status and mother's education. Further research should be aimed at ways to make health education more effective among uneducated parents.

Blood cultures from Bangladeshi children with septicaemia: an evaluation of conventional, lysis-direct plating and lysis-centrifugation methods.

Abstract: The use of a laboratory-made lysis-direct plating and lysis-centrifugation (LDP/LC) device for blood cultivation has been compared with the conventional broth culture method in respect of speed and sensitivity in detecting organism(s) and cost effectiveness. 400 blood cultures yielded 95 clinically significant isolates. Both methods recovered 73 organisms (76.8%); 20 (21%) were detected by LDP/LC methods only, and 2 (2.1%) were isolated by the conventional method only. All the 93 isolates (97.8%) recovered by LDP/LC were isolated within 48 h, whereas the broth culture method took 7 d to isolate a total of 75 organisms (78.9%). The LDP/LC method, with our laboratory-made device, costs one-fourth of the cost of the conventional broth culture system.

Seroprevalence of enteric and nonenteric adenoviruses in Bangladesh.

Abstract: Single serum samples obtained from infants between 0 and 24 months of age admitted to a diarrheal disease hospital in Bangladesh were tested for the presence of adenovirus-specific immunoglobulin G (IgG) and IgA antibodies by using enzyme immunoassay and neutralizing antibodies to adenovirus types 2, 40, and 41. IgG antibodies were more prevalent than IgA antibodies, and neutralizing activity to enteric adenovirus was found in serum samples from 50% of infants who had reached 2 years of age.