Vibrio Isolates 2019

There were no isolates confirmed as being toxigenic cholera this year. There was one isolate, which identified as Vibrio cholerae O139 but was non toxigenic.

There was an outbreak of Vibrio parahaemolyticus in May 2019. Isolates from outbreak cases clustered genomically and were confirmed as being the pandemic ST36 strain. The majority of cases consumed locally acquired raw or partially cooked mussels prior to illness.

Historically Vibrio parahaemolyticus data is confounded in a number of ways, highlighted during the above outbreak: The organism is notifiable in NZ but only under "Acute gastroenteritis". Diagnostic laboratory detection methods vary widely; laboratory referral of isolates to ESR was sporadic. Communications during and following the outbreak have resulted in improved notification and referral of isolates.