Human Salmonella Isolates, 2014 No. 5, May

The number of isolates (n=96) showed a decrease in comparison with May 2013 (n = 108). Salmonella Infantis (14.8% in May 2013, 8.3% in May 2014) was the predominant serotype. Uncommon Salmonella serotypes confirmed this month included: S. Havana (11 humans isolates since 2002), S. Muenchen (12 human isolates since 2002), and S. Victoria (11 isolates since 2002). Salmonella Typhi phage type E4 was isolated for the first time in New Zealand. The case had recently travelled to Vanuatu.

Cluster of S. Typhimurium phage type 120 (Wellington)

Four cases of S. Typhimurium phage type 120 were confirmed this month. This phage type has been associated overseas with increased antimicrobial resistance. The 4 isolates were referred to the Antibiotic Reference Laboratory at ESR and results indicated that all isolates were susceptible to the antibiotics tested. PFGE analysis was also performed and showed an indistinguishable profile shared by the isolates suggesting a common source outbreak.