During the second quarter of 2017 (2Q17), the Western Australian (WA) OzFoodNet team conducted surveillance of enteric diseases, undertook investigations into outbreaks and was involved with ongoing enteric disease research projects. The most common notifiable enteric infections in WA were campylobacteriosis (n=705), salmonellosis (n=622), rotavirus infection (n=236) and cryptosporidiosis (n=89). Compared to the applicable 5-year second quarter means (2QM), there were increases in notifications of campylobacteriosis (23%), salmonellosis (74%), rotavirus infections (134%) and cryptosporidiosis (21%).
The large increase in salmonellosis was primarily driven by an increase in S. Typhimurium MLVA type 03-17-09-12-523 notifications. There were six foodborne outbreaks investigated in the second quarter, all due to Salmonella Typhimurium and four of which were associated with consumption of egg dishes. The number of foodborne outbreaks in the 2Q17 was nearly two times the second quarter 5-year mean (n=3.4). OzFoodNet also conducted surveillance of 34 non-foodborne outbreaks. Of these, the most common mode of transmission was person-to-person (25 outbreaks), with a total of 431 people ill. Norovirus was the most commonly reported pathogen, being identified in 13 outbreaks.