Y-018. An Epidemiological Investigation on the Distribution of Drug-Resistant Salmonella enterica serovar Javiana Outbreaks in Arkansas

J. Deck1, R. Nayak1, R. Stefanova2;
1Natl. Ctr. for Toxicological Research, Jefferson, AR, 2Arkansas Pub. Hlth. Lab., Little Rock, AR.

Salmonella is a major foodborne pathogen. Among Salmonella serovars, S. Javiana infections in the U.S. are on the rise. Few data are available on the genetics and evolutionary characteristics of this emerging pathogen. The objective of this study was to analyze the epidemiological spread of S. Javiana infections in Arkansas and analyze the patterns of drug resistance. Clinical S. Javiana isolates (n=386) were obtained from the Arkansas Public Health Laboratories. These strains were submitted to the APHL by the state clinics from 2003 to 2008, and were implicated in hospital and food-related outbreaks in Arkansas. The demographical data of this pathogen was analyzed based on years, age, gender, and county. The antimicrobial susceptibility profiles were determined by measuring the MIC values using the CLSI criteria. Nearly 48% of S. Javiana infections occurred in 2003 and 2004. S. Javiana was isolated from ~58% of patients under the age of 10, and 21% for each of the age groups between 11 to 49 and 50 to 70. Male patients (57%) were more susceptible to S. Javiana infections than females (43%). S. Javiana infections were prevalent in central Arkansas (59%) region compared to northeastern (24%) and western (12%) regions of the state. Only 8% of the isolates were susceptible to the antimicrobials tested. Nearly 91% of the strains elicited resistance to sulfisoxazole, while 2% of the isolates were resistant to 2 or 3 antimicrobials, including nalidixic acid, cefoxitin, streptomycin, or tetracycline. This study demonstrated an annual decline (9 to 17%) in S. Javiana populations in Arkansas since 2004. Comparative analysis indicated that infants and children were more susceptible than adults, and the predominant concentration of the S. Javiana infections was in central Arkansas counties. With the exception of sulfa drugs, S. Javiana strains were susceptible to most drugs tested, suggesting that infections caused by this emerging pathogen can be easily contained in outbreak scenarios. DNA fingerprinting is conducted to determine whether the isolates were epidemiologically related or if they represent unrelated introductions in the hospital environment.