Human Salmonella isolates, 2021 No.02, February

The number of isolates (n=78) confirmed this month showed a decrease in comparison to the number of isolates confirmed in February 2020 (n=91). Salmonella Enteritidis ST183 (42.3% in February 2021 vs 5.5% in February 2020) was the most common serotype confirmed this month.

An increase in notifications of Salmonella Enteritidis predominantly in the South Island (Source: EpiSurv 1100 hours 08 March 2021, ESR Enteric Reference Laboratory. Ministry for Primary Industries)

• There has been 1 new case of Salmonella Enteritidis (SEN) reported in the last week bringing the total to 38 cases since 27 January 2021.
• Sequencing results show 28 of the recent SEN cases are ST183 and are genetically clustered, 9 cases are not part of the cluster and sequencing results are pending for the remaining case.
• The 28 cases in the cluster are from Canterbury (18), Nelson Marlborough (4), Capital and Coast (3), South Canterbury (2) and Southern (1) DHBs. Note 2/3 Capital and Coast cases were in the South Island during their incubation periods. The third case was unable to be contacted for interview.
• The majority of cases are aged 20 years or older (89%, 25/28 cases). 17 cases (61%) are female. 7 cases (25% 7/28) have been hospitalised. Onset dates have been recorded for 21 cases and range from 24 January to 18 February 2021.

Due to COVID-19 effect on overseas travel and habits of the community post lockdown, there has been a downturn in the number of Salmonella samples.