Are Salmonella-Induced Gastroenteritis Neglected in Developing Countries? Feedback from Microbiological Investigations in N'Djamena Hospitals, Chad.

Salmonella is considered to be one of the main pathogens causing human gastroenteritis worldwide. Looking for Salmonella in Africa in patients suffering from gastroenteritis is rather unusual, and the use of antibiotics is not subject to any regulation. This study intends for stressing the possible prominent importance of Salmonella in digestive diseases in Africa as well as identifying antimicrobial resistance of Salmonella isolates from faeces samples of human origin. All samples were collected from five N'Djamena hospitals, from patients suffering from diarrhoea. The collecting was undertaken over two periods of six months each: from August 2010 to January 2011 and from September 2011 to February 2012. Salmonella isolates were obtained by standard cultivation and serotyping methods. A total of 43 Salmonella isolates were identified, belonging to 21 different serovars. The most prevalent serovar was Salmonella Stanleyville (n = 7), followed by S. Anatum (n = 4) and S. Kottbus (n = 3). The other serovars were under-represented. The majority of these isolates were susceptible to all antibiotics tested (CLSI Standards), except two S. Enteritidis isolates that exhibited resistance to fluoroquinolones. The different serovars and antibiotic resistance profiles that were observed highlight the substantial diversity of Salmonella in N'Djamena, Chad. Roughly, one out of ten patients who consulted for gastroenteritis was shedding Salmonella spp. and none of them would have been diagnosed outside the context of this research program. This study may encourage local clinicians to explore more often salmonellosis suspicion in their daily practice.

Prevalence and antimicrobial resistance of non-typhoidal Salmonella serotypes isolated from laying hens and broiler chicken farms in N'Djamena, Chad.

This study aimed at updating knowledge on the prevalence and antimicrobial resistance characteristics of Salmonella isolated from poultry in the province of N'Djamena, Chad. The results collected during this study provide the first baseline data on the prevalence of contamination by Salmonella in laying hens and broiler chicken farms in N'Djamena. All samples were collected from sixteen poultry farms over two periods of six months each: from August 2010 to January 2011 and from September 2011 to February 2012. Diagnostic methods used during this study allowed to isolate eighty four Salmonella strains, belonging to twenty seven different serotypes. The most frequent serotypes were Salmonella Colindale (19%) followed by S. Minnesota (18%) S. Havana and S. Riggil (each 6%), S. Kottbus and S. Amager (4.7%), S. Idikan, Mississipi, and Muenchen (3.6%). Other serotypes were poorly represented. The majority of these serotypes were susceptible to all antibiotics tested (CLSI Standards), except some S. Colindale isolates that exhibited a decreased susceptibility to fluoroquinolones, S. Limete resistant to three antibiotics and S. Minnesota isolates resistant to five different antimicrobial classes. The different serotypes and antibiotic resistance profiles that were observed highlight the substantial diversity of Salmonella in Chad, the contribution of avian isolates to human salmonellosis and Salmonella's capacity to colonize all types of environment worldwide.