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Background: Accurate etiological diagnosis of meningitis in developing countries is needed, to improve clinical care and to optimize disease-prevention strategies. Cerebrospinal fluid (CSF) culture and latex agglutination testing are currently the standard diagnostic methods but lack sensitivity., Methods: We prospectively assessed the utility of an immunochromatographic test (ICT) of pneumococcal antigen (NOW Streptococcus pneumoniae Antigen Test; Binax), compared with culture, in 5 countries that are conducting bacterial meningitis surveillance in Africa and Asia. Most CSF samples were collected from patients aged 1-59 months., Results: A total of 1173 CSF samples from suspected meningitis cases were included. The ICT results were positive for 68 (99%) of the 69 culture-confirmed pneumococcal meningitis cases and negative for 124 (99%) of 125 culture-confirmed bacterial meningitis cases caused by other pathogens. By use of culture and latex agglutination testing alone, pneumococci were detected in samples from 7.4% of patients in Asia and 15.6% in Africa. The ICT increased pneumococcal detection, resulting in similar identification rates across sites, ranging from 16.2% in Nigeria to 20% in Bangladesh. ICT detection in specimens from culture-negative cases varied according to region (8.5% in Africa vs. 18.8% in Asia; P< .001), prior antibiotic use (24.2% with prior antibiotic use vs. 12.2% without; P< .001), and WBC count (9.0% for WBC count of 10-99 cells/mL, 22.1% for 100-999 cells/mL, and 25.4% for >or=1000 cells/mL; P< .001 by test for trend)., Conclusions: The ICT provided substantial benefit over the latex agglutination test and culture at Asian sites but not at African sites. With the addition of the ICT, the proportion of meningitis cases attributable to pneumococci was determined to be similar in Asia and Africa. These results suggest that previous studies have underestimated the proportion of pediatric bacterial meningitis cases caused by pneumococci.

Although for over 20 years the Field Epidemiology Training Programs (FETPs) have provided a model for building epidemiology capacity in Ministries of Health worldwide, the model does not address laboratory training and its integration with epidemiology. To overcome this, Kenya added a laboratory management component in 2004, creating the first field epidemiology and laboratory training program (FELTP) to train both medical and laboratory epidemiologists. Laboratory management and epidemiology candidates were recruited from among degree-holding scientists at the Ministry of Health and trained in both applied epidemiology and laboratory management using a combination of short courses and extensive field placements. The course generated a cohort of laboratory epidemiologists with demonstrated capacity in disease surveillance and management of outbreaks. Early indicators suggest programmatic success: the start of laboratory-based disease reporting and better laboratory involvement in outbreak responses.

Objective: To determine the association between Plasmodium falciparum malaria and non-typhi Salmonella in children., Design: Cross-sectional hospital based study., Setting: Kilifi District Hospital (KDH) between January 1997 and June 2001., Subjects: Children aged between three months to 123 months (mean age 28.28 months) and who had been admitted to the paediatric or High Dependency Research Ward (HDRW) of the KDH., Methods: A total of 19, 118 blood cultures routinely obtained for all admissions and 1,820 clinically indicated stools samples were obtained from 9,147 children admitted with malaria. The specimens were cultured and antibiotic sensitivity done using standard laboratory procedures with stringent internal and external quality control in place., Results: The total bacterial pathogens isolated from blood and stool were 1,395/19,118 (7.3%) and 342/1,820 (19%) respectively. Non-typhi salmonella consisted of 260/1,395 (18.6%) of the positive blood cultures and 92/324 (28.4%) of the stool cultures out of which a total of 101 NTS occurred in children with severe malaria. Out of the 9,147 malaria cases admitted, 101/9,147 (1.10%) had concomitant NTS infection. NTS with severe malaria as a proportion of all malaria admissions for the period varied between 0.8% and 1.5%. There was a significant association (p-value=0.032) between clinical outcome of death and female sex of the patient. The NTS isolates which occurred with severe malaria showed various levels of antibiotic resistance. They were resistant to ampicillin (35%), chloramphenicol (18%), gentamicin (22%), cefuroxime (29%), sulphamethoxazole-trimethoprim (39%), ciprofloxacin (3%), cefotaxime (14%), amoxycillin-clavulanic acid (26%) and tobramycin (18.0%). Multidrug resistance (MDR) was seen in 34 (33.6%) of the isolates., Conclusions: NTS and severe malaria occurring together are a problem in this area and that a large number of the isolates are MDR. An elaborate case-controlled study is required to elucidate the chain of events of both NTS and malaria parasite co-existence.

Diarrheal disease is one of the major causes of morbidity and mortality in developing countries. Drinking water is a primary transmission route of infectious diarrheagenic bacteria in a rural area of Kenya (Microbiol. Immunol. 41: 773-778, 1997). We tried to prevent diarrhea at villages with approximately 1,500 households in Kenya by pasteurizing drinking water. A durable simple thermoindicator which changes color at 70 C was used as an indicator of pasteurization. The number of households in which drinking water was coliform bacteria-free increased from 10.7% to 43.1% after adoption of a pasteurization practice. Consequently, the incidence of severe diarrhea among people drinking pasteurized water was significantly lower than in people taking raw water (odds ratio=0.55, P=0.0016). The reduction ratio of the incidence after pasteurization was nearly equivalent with that after the adoption of a boiling method. Employment of women leaders as fieldworkers and demonstration of bacterial colony disappearance on agar plates by pasteurization also affected reduction of the diarrheal incidence.

A combination of phage typing and pulsed-field gel electrophoresis of Xbal-digested chromosomal DNA has been used to study the epidemiological relationships of multidrug-resistant Salmonella enterica serotype typhimurium from Nairobi (64 isolates) and Kilifi (40 isolates) collected over the period 1994-1997. Isolates from Nairobi belonged to 11 definitive phage types (DTs) encompassing eight different PFGE patterns. In contrast, isolates from Kilifi were mainly DT 56 (60%) and all fell into a single PFGE pattern. The remaining isolates did not conform to a recognisable phage type. We conclude that multidrug-resistant S. typhimurium infections from Nairobi were caused by multiple strains while those from Kilifi were likely to be from a microepidemic caused by a single clone.

A 4-year retrospective study was undertaken at the Kilifi District Hospital on the coast of Kenya to determine the antibiotic-susceptibility patterns and genotypes of non-typhi Salmonella (NTS) isolates from children. Overall, during the period 1994-97, positive cultures were obtained from 543 (14%) of 3885 blood samples, 364 (30%) of 1210 stool samples and 143 (11%) of 1283 cerebrospinal fluid (CSF) samples. NTS were isolated from 151 (27.8%), 72 (19.8%), and 11 (7.7%) of these positive cultures, respectively. The total 234 NTS isolates were serotyped: the most frequent were Salmonella enterica serotype Enteritidis (41%) and S. enterica serotype Typhimurium (38%). Antibiotic sensitivity testing was done using ampicillin (amp), chloramphenicol (chl), gentamicin (cn), co-trimoxazole (s-t), cefuroxime (cxm), ciprofloxacin (cip), cefotaxime (ctx), amoxicillin-clavulanic acid 20 micrograms-10 micrograms (amc), and tobramycin (tob). Of the 234 isolates, 43 were sensitive to all antibiotics tested and 133 were multiple drug resistant (MDR). The most common resistance type seen was amp, cn, cxm, s-t, ctx, amc, tob (36/234). Our results indicate a high proportion of MDR amongst the isolates from Kilifi. We conclude that 2 major serotypes of salmonella, i.e., S. enterica serotype Typhimurium and S. enterica serotype Enteritidis, of micro-epidemic nature that have been previously unrecognized in Kilifi are responsible for infection in Kilifi district on the coast of Kenya and that over half (56.8%) of total NTS isolates are MDR.

To study the association of multidrug-resistant enteroaggregative Escherichia coli with persistent diarrhea in Kenyan children, stool specimens were obtained from 862 outpatients under 5 years of age from July 1991 to June 1993. E. coli O44 was identified as the sole bacterial pathogen in four patients experiencing at least 14 days of fever, vomiting, and diarrhea. Disk diffusion testing showed E. coli O44 resistance to tetracycline, ampicillin, erythromycin, trimethoprim-sulphamethoxazole, and amoxicillin/clavulanate and sensitivity to chloramphenicol, nalidixic acid, azithromycin, and cefuroxime. Further studies are needed to clarify the epidemiology, clinical spectrum, and pathogenesis of enteroaggregative E. coli infection.

Diarrheal diseases are major causes of morbidity and mortality among children in developing countries. We have analyzed the causative agents of diarrhea in children under five years of age who resided in rural environments but attended a hospital in Malindi, a coastal town in Kenya. Bacterial diarrhea was found in 239 (27.7%) of 862 patients with diarrhea. Diarrheagenic Escherichia coli, including enteropathogenic, enterotoxigenic, and enterohaemorrhagic strains, was isolated from 119 (13.8%) patients, followed by Salmonella spp. (63 cases, 7.3%) and Shigella spp. (56 cases, 6.5%). Intestinal parasites were found in 109 (12.6%) of the patients. Entamoeba histolytica and Giardia lamblia were found in 67 (7.8%) and 42 (4.9%) of the cases, respectively. Rotavirus was found in 69 (16.1%) of 428 cases, a part of the 862 cases. Significant differences in age distribution were seen in diarrheal cases due to Campylobacter spp., G. lamblia, and rotavirus. No significant seasonal incidence of specific pathogens was found, but the number of diarrheal patients was significantly correlated to rainfall. Drinking water was contaminated with bacteria at concentrations ranging from 10(3) to 10(6) CFU/ml in 98% of the households and by coliform bacteria at concentrations of 10(2) to 10(5) CFU/ml in 72% of the households. These results suggest that the main routes of infection may be contaminated drinking water and fecal-oral transmission of enteric pathogens. Consequently, we propose that the enhancement of hygienic practice through health education is a feasible control measure of diarrhea in the study area.

Sixty-eight strains of multi-drug resistant Shigella dysenteriae type 1 were isolated from outbreaks of severe dysentery in three areas of Kenya, namely, Kisumu, Mombassa and Nairobi. The strains were tested for their susceptibility to seven antibiotics. Plasmids were extracted to study their variety and conjugated with Escherichia coli K12 to identify the plasmid coding for the resistance gese. All the strains were resistant to ampicillin, trimethoprim-sulfamethoxazole (S-T), tetracyciine and chloramphenicol. They were sensitive to gentamicin, kanamycin and nalidixic acid. Part of the resistance was found to be plasmid mediated and the sizes of plasmids coding resistance gene wereSMDaand 19MDa. These piasmids coded resistance for ampicillin, trimethoprim-sulfamethoxazole, tetracyciine and chloramphenicol. Verotoxin (VT) production was demonstrated in 80% of the strains by oligonucleotide DNA-DNA gybridization of whole cells with the VT-probe. In view of the extent of drug resistance exhibited by Shigella dysenteriae Type 1 in this study, we recommend the use of nalidixic acid as a first choice of treatment in multiresistant S. dysenteriae Type 1 dysentery outbreaks. Compared to the other two agents that the pathogen was sensitive to, nalidixic acid is relatively cheap with the cost of 7 days treatment for an adult being approximately five US dollars. Resistance to nalidixic acid has to be, however, closely monitored as S. dysenteriae Type 1 has been reported to develop resistance to this drug over time.

Thirty-seven strains of E. coli recovered from cases of septicaemia in chicken were tested for sensitivity to 6 antibiotics. Minimum inhibitory concentration (MIC) determinations done on the strains showed resistance to trimethoprim-sulfamethoxazole (septrin) (100%), ampicillin (62.2%), tetracycline (51.4%), kanamycin (13.5%) and gentamicin (2.7%). All were sensitive to chloramphenicol. Conjugation studies showed easy transfer of the resistance factor for septrin to the recipient sensitive strain, K12F-, a 60 megadalton plasmid was transferred in most of the cases (a number of plasmids moved across to K12F- strains). Septrin was chosen as a referral antibiotic because it is used extensively for treating diarrhoeal cases in children in Kenya. The results expressed the possibility of the chicken being the possible source of the septrin resistance gene (plasmid) for humans, and vice versa.

A number of serotypable E. coli, Salmonella and Shigella strains isolated from three districts in Kenya were investigated for carriage of plasmids. This was done through extraction of plasmids and separating them by electrophoresis on agarose. Most of the strains investigated showed presence of plasmids. The E. coli isolates had plasmids ranging in number from 1 to 5, the most common number was 2. The plasmid sizes ranged from 80 to 30 megadalton, the commonest of the heavy plasmids were 70 megadalton. The Shigella isolates had plasmids ranging in number from 1 to 3, the most common number was 1. The plasmid sizes ranged from 80 to 3.5 megadalton, the commonest of the heavy plasmids were 70 megadalton. Various plasmid-sizes have been published as being responsible for pathogenicity.