[Epidemiology of acute bacterial diarrhea in children in Libreville, Gabon]

Prevalence of Pathogens in Young Children Presenting to Hospital with Diarrhea from Lambaréné, Gabon

Diarrheal disease is the second most frequent cause of mortality in children younger than 5 years worldwide, causing more than half a million deaths each year. Our knowledge of the epidemiology of potentially pathogenic agents found in children suffering from diarrhea in sub-Saharan African countries is still patchy, and thereby hinders implementation of effective preventative interventions. The lack of cheap, easy-to-use diagnostic tools leads to mostly symptomatic and empirical case management. An observational study with a total of 241 participants was conducted from February 2017 to August 2018 among children younger than 5 years with diarrhea in Lambaréné, Gabon. Clinical and demographic data were recorded, and a stool sample was collected. The samples were examined using a commercial rapid immunoassay to detect Rotavirus/adenovirus, conventional bacterial culture for Salmonella spp., and multiplex real-time PCR for Cryptosporidium spp., Giardia lamblia, Cyclospora cayetanensis, enterotoxigenic Escherichia coli (ETEC), and enteroinvasive Escherichia coli (EIEC)/Shigella. At least one infectious agent was present in 121 of 241 (50%) samples. The most frequently isolated pathogens were EIEC/Shigella and ETEC (54/179; 30.2% and 44/179; 24.6%, respectively), followed by G. lamblia (33/241; 13.7%), Cryptosporidium spp. (31/241; 12.9%), and Rotavirus (23/241; 9.5%). Coinfection with multiple pathogens was observed in 33% (40/121) of the positive cases with EIEC/Shigella, ETEC, and Cryptosporidium spp. most frequently identified. Our results provide new insight into the possible causes of diarrheal disease in the Moyen-Ogooué region of Gabon and motivate further research on possible modes of infection and targeted preventive measures.

Urban inputs of fecal bacteria to the coastal zone of Libreville, Gabon, Central Western Africa

Libreville, the largest city in Gabon, adversely impacts the Komo Estuary and the Akanda National Park aquatic ecosystems through discharge of domestic and industrial waste. Fecal Indicator Bacteria (FIB: Escherichia coli and fecal streptococci) were enumerated using culture-based methods in water from 40 sites between 2017 and 2019 including coastal outlets, mangrove channels, open bays and littoral rivers. Contamination levels were high in discharge waters from small urban rivers in Libreville agglomeration, frequently exceeding international safety guidelines, whereas FIB concentrations decreased downstream from the city in main mangrove channels. Littoral forest rivers were significantly impacted by fecal contamination despite the absence of settlements in the watersheds. Protected areas are not effective in avoiding FIB contamination, indicating inefficient waste management. Dedicated management policies should be implemented to reduce both the sanitary concern and global pollution, poorly assessed in a context of demographic increase in tropical littoral zones.

Molecular prevalence of intestinal parasites infections in children with diarrhea in Franceville, Southeast of Gabon

Background

Pediatric diarrhea caused by a range of pathogens, including intestinal parasites, is one of main causes of death among children under 5 years of age. The distribution of these parasitic infections overlaps in many environmental, socioeconomic and epidemiological settings. Their distribution and prevalence varies from region to region. In the current study, we assess the prevalence of intestinal parasites among pediatric patients with syndromic diarrheal disease living in Franceville, Gabon.

Methods

A cross-sectional study conducted in the Amissa Bongo Regional Hospital and Chinese-Gabonese Friendship Hospital in Franceville, between November 2016 and August 2017, enrolled a total of 100 diarrheic children between 0 and 180 months of age. Parasite detection in stool samples was performed using molecular diagnostic by PCR. Difference in means were tested by Student’s t test and ANOVA while principal component analysis was used to determine the correlation between parasite distributions and age groups.

Results

The overall prevalence of intestinal parasite infection was 61% (61/100). Hymenolepis sp and Cryptosporidium hominis/parvum were the most common parasites (31 and 19%, respectively), followed by Encephalitozoon intestinalis (15%), Trichuris trichiura (4%), Dientamoeba fragilis (4%), and Enterocytozoon bieneusi (2%). The polyparasitism rate was 19.7%, with 83.3% double and 16.7% triple infections. Protozoan infections (66.7%) were more prevalent than helminths infections (33.3%). Seasonal association of the circulation of intestinal parasite was statistically significant (p = 0.03). Correlations between different parasites was also observed.

Conclusion

The prevalence of intestinal parasitic infections is highest in diarrheic pediatric children. The prevalence of parasitic infections indicates that protozoa and helminths are the most common parasites in the Franceville environment. This study reinforces the importance of routine examination of diarrheic stool samples for the diagnostic of intestinal parasites. Further analyses are required to better understand the local epidemiology and risk factors associated with the transmission of intestinal parasites in Franceville, Gabon.

Keyswords

diarrhea, children, intestinal parasitic infections, molecular diagnostic, Franceville, Gabon.