부산대학교 도서관

Background: Despite the importance of non-Typhoidal Salmonella (NTS) disease in Africa, epidemiologic data on carriage and transmission are few. These data are important to understand the transmission of NTS in Africa and to design control strategies. Method: Ethics statement: The study was approved by the KEMRI Scientific and Ethics Research Unit (SERU No. 3221). This activity was reviewed by CDC and was conducted in a manner consistent with applicable federal law and CDC policy [Project ID: 0900f3eb81e92cdd]. To estimate the prevalence of stool carriage of NTS in Kenya, we conducted a cross-sectional study in Kilifi, Nairobi, and Siaya, sites with a low, moderate and high incidence of invasive NTS disease, respectively. At each site, we randomly selected 100 participants in each age-group of 0–11 months, 12–59 months, 5–14 years, 15–54 years and ≥55 years. We collected stool, venous blood (for hemoglobin and malaria rapid tests), anthropometric measurements, and administered a questionnaire on Water Access Sanitation and Hygiene (WASH) practices. Stool samples were cultured on selective agar for Salmonella; suspect isolates underwent serotyping and antimicrobial susceptibility testing. Result: Overall, 53 (3.5%) isolates of NTS were cultured from 1497 samples. Age-adjusted prevalence was 13.1% (95%CI 8.8–17.4) in Kilifi, 0.4% (95%CI 0–1.3) in Nairobi, and 0.9% (95%CI 0–2.0) in Siaya. Prevalence was highest among those aged 15–54 years (6.2%). Of 53 isolates; 5 were S. Enteritidis, 1 was S. Typhimurium. No S. Typhi was isolated. None of the risk factors were associated with carriage of NTS. All isolates were susceptible to all antibiotics tested, including ampicillin, chloramphenicol, ciprofloxacin and co-trimoxazole. Conclusion: Prevalence of fecal carriage was high in Kilifi, an area of low incidence of invasive NTS disease and was low in areas of higher incidence in Nairobi and Siaya. The age-prevalence, risk factors, geographical and serotype distribution of NTS in carriage differs from invasive disease. Author summary: Infections with non-typhoidal Salmonella (NTS) bacteria can present as asymptomatic carriage, diarrhoea or invasive disease. Worldwide, invasive NTS disease (iNTS) is more common in Africa, especially among children, and is commonly caused by two serotypes: S. Typhimurium and S. Enteritidis. Recent studies suggest that transmission of these serotypes causing iNTS is human to human. Consequently, identifying the age-group and risk factors associated with asymptomatic carriage of NTS would help in controlling its transmission. We randomly sampled healthy children and adults across 3 sites in Kenya with carrying iNTS incidence. We found that carriage is highest among older children and adults, who can be targeted to reduce its transmission. We also found that carriage was highest in Kilifi, the area of low iNTS incidence, it was not associated with known risk factors for iNTS, and majority of the serotypes were neither S. Typhimurium nor S. Enteritidis. These differences between NTS carriage and invasive disease need further investigations to understand the linkages and inform control. [ABSTRACT FROM AUTHOR]