Distribution of viable and culturable Vibrio cholerae in MagaLake, Far North Region of Cameroon: preliminary findings Maïworé Justine1, Moussa Djaouda1*, Tatsadjieu Ngouné Léopold2, J. Glenn Morris Jr3, Moïse Nola4 and Song Liang3,5. 1
Higher Teachers’ Training College, University of Maroua, PO Box 55 Maroua, Cameroon. IUT, Université de Ngaoundéré, Cameroun 3 Emerging Pathogens Institute, University of Florida, Gainesville, FL 32610 4 Laboratory of General Biology, University of Yaoundé I, PO Box 812 Yaoundé, Cameroon. 5 Department of Environmental and Global Health, College of Public Health and Health Professions, University of Florida, Gainesville, FL 32610 2
* Corresponding author:
[email protected], +237 699 75 80 00/ 675 65 00 86 Cholera has been endemic in Cameroon since 1971 and the northern part of the country (e.g. the North and Far North regions) is considered one of the cholera epicenters. The 2010-11 major cholera outbreak hit all over Cameroon and it was speculated that the outbreak was initiated in the Far North Region and spread throughout the country. However, little is known on how the outbreak took place and how the disease spread. In this study we aim to explore potential environmental reservoir of Vibrio cholerae in the Far North Region with a focus on Maga Lake. Maga Lake is located in a large plain of the Far North Region and floods each year. The people living around the Maga Lake are among the most affected population by cholera during the 2010-2011 outbreaks. In July 2011during the rainy season, we selected three sites in Maga Lake and collected samples thrice from various sources (500 mL of water, 50 g of sediments, fish) at different sampling points and the samples were examined for contamination with V. cholerae. Other microbiological parameters and physicochemical characteristics (pH, temperature, salinity and turbidity) of the water were also measured.The Spearman’s Rank correlation was used to analyze the relationship between physico-chemical factors and the occurrence of V. cholerae. Results showed that the abundance of heterotrophic aerobic and mesophilic bacteria (1.60±0.7x106 UFC/mL) and bacterial bioindicators in lake water all exceeded the WHO’s recreational water standards. Faecal streptococci were present in all water samples at high concentrations (31±0.64 UFC/100 mL). In sediments, the abundance of heterotrophic aerobic and mesophilic bacteria reached 2.07±0.06x1010 UFC/mL. Vibrio metschnikovii was the only species of Vibrio genus found in water samples. However, sediments were contaminated with three species of Vibrio genus: V. parahaemoliticus, V. metschnikovii and V. cholerae. We found V. vulnificus and V.
alginolyticus from fish samples. Further investigations are needed to understand how viable and culturable V. cholerae moves from one compartment of the lake to another and how flooding modulates cholera transmission from the Maga Lake.
