Human salmonella isolates 2022

Note: 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.

Following the opening of NZ borders, the number of Salmonella isolates confirmed this year (n=738) showed an increase in comparison with 2021 (n= 668). Salmonella Typhimurium ST19 was the predominant sero/genotype, representing 27.4% of total isolates. Salmonella serotypes showing an increase this year in comparison with 2021 included: Salmonella Kintambo (from 0.0% to 0.9%), Salmonella Paratyphi A (from 0.3% to 1.8%), Salmonella Stanley (from 1.4% to 2.4%), S. Typhi (from 0.4% to 3.9%) and S. Infantis (from 0.0% to 1.2%). Salmonella serotypes showing a decrease this year in comparison with 2021 included: S. Enteritidis (from 19.3% to 10.7%).

• A cluster of 24 cases of Salmonella Typhimurium ST19, locally designated 5-SNP cluster type _2022_C_12, which was detected between July and August 2022 and associated with travel to Fiji. A source was not confirmed.

• An outbreak of 7 cases of Salmonella Kintambo ST8754, associated with consumption of sesame-based products, which was detected in July and August 2022. This the first time the presence of Salmonella Kintambo has been detected in New Zealand. A consumer level recall was undertaken due to the possible presence of Salmonella https://www.mpi.govt.nz/food-safety-home/food-recalls-and-complaints/recalled-food-products/algota-brand-sesame-tahini/

• Twelve cases adding to the Salmonella Enteritidis ST11 locally designated 5-SNP cluster type _2019_C_01. The cases were geographically dispersed. The source for the outbreak was confirmed as being from the poultry industry.

The number of isolates (n=64) confirmed this month showed a decrease in comparison to the number of isolates confirmed in January 2021 (n=85). Salmonella Typhimurium ST19 (22.4% in 2021 vs 20.3% in 2022) was the most common serotypes confirmed this month.

The number of isolates (n=72) confirmed this month showed a decrease in comparison to the number of isolates confirmed in February 2021 (n=85). Salmonella Typhimurium ST19 (16.6% in 2021 vs 26.3% in 2022) was the most common serotypes confirmed this month.

The number of isolates (n=45) confirmed this month showed a decrease in comparison to the number of isolates confirmed in March 2021 (n=78). Salmonella Typhimurium ST19 (23% in 2021 vs 35.6% in 2022) was the most common serotypes confirmed this month.

The number of isolates (n=74) confirmed this month showed a decrease in comparison to the number of isolates confirmed in April 2021 (n=79). Salmonella Typhimurium ST19 (31.6% in April 2021 vs 45.9% in April 2022) was the most common type confirmed this month. Uncommon serotype confirmed this month was Salmonella Butantan (3 human cases since it was first confirmed in New Zealand in 2004).

The number of isolates (n=61) confirmed this month showed an increase in comparison to the number of isolates confirmed in May 2021 (n=50). Salmonella Typhimurium ST19 (26% in May 2021 vs 26.2% in May 2022) was the most common type confirmed this month.

The number of isolates (n=54) confirmed this month showed a slight decrease in comparison to the number of isolates confirmed in June 2021 (n=57). Salmonella Typhimurium ST19 (24.6% in June 2021 vs 20.4% in June 2022) was the most common serotype confirmed this month. Uncommon serotype confirmed this month was Salmonella Apeyeme (6 human cases since it was first confirmed in New Zealand in 2011). Salmonella Kintambo was confirmed for the first time in humans in New Zealand this month. 

The number of isolates (n=45) confirmed this month showed a slight increase in comparison to the number of isolates confirmed in July 2021 (n=42). Salmonella Typhimurium ST19 (7.1% in July 2021 vs. 26.6% in July 2022) was the most common serotype confirmed this month. Uncommon serotype confirmed this month was Salmonella Kintambo (3 human cases since it was first confirmed in New Zealand in 2022). 

The number of isolates (n=74) confirmed this month showed an increase in comparison to the number of isolates confirmed in August 2021 (n=34). Salmonella Typhimurium ST19 (35.3% in August 2021 vs 35.1% in August 2022) was the most common serotype confirmed this month. Uncommon serotype confirmed this month was Salmonella Kintambo (5 human cases since it was first confirmed in New Zealand in 2022).

The number of isolates (n=57) confirmed this month showed an increase in comparison to the number of isolates confirmed in September 2021 (n=40). Salmonella Typhimurium ST568 (12.5% in September 2021 vs. 24.6% in September 2022) was the most common serotype confirmed this month. Uncommon serotypes confirmed this month were Salmonella Bredeney (13 human cases since it was first confirmed in New Zealand in 1991) and Salmonella Minnesota (3 human cases since it was first confirmed in New Zealand in 1998).

The number of isolates (n=61) confirmed this month showed an increase in comparison to the number of isolates confirmed in October 2021 (n=33). Salmonella Typhimurium ST568 (15.2% in October 2021 vs. 23% in October 2022) was the most common serotype confirmed this month. Uncommon serotypes confirmed this month were Salmonella Coeln (2 human cases since it was first confirmed in New Zealand in 2017) and Salmonella Kintambo (7 human cases since it was first confirmed in New Zealand in 2022).

The number of isolates (n=75) confirmed this month showed an increase in comparison to the number of isolates confirmed in November 2021 (n=46). Salmonella Typhimurium ST19 (2.2% in November 2021 vs. 28% in November 2022) was the most common serotype confirmed this month. Uncommon serotypes confirmed this month were Salmonella Choleraesuis var. Kunzendorf (7 human cases since it was first confirmed in New Zealand in 1989) and Salmonella Galiema (3 human cases since it was first confirmed in New Zealand in 2000).

The number of isolates (n=56) confirmed this month showed an increase in comparison to the number of isolates confirmed in December 2021 (n=42). Salmonella Typhimurium ST568 (14.3% in December 2021 vs 21.4% in December 2022) was the most common serotypes confirmed this month. Uncommon Salmonella serotypes confirmed this month were S. Grumpensis (3 human isolates since it was first confirmed in New Zealand in 2000) and S. Liverpool (7 human isolates since it was first confirmed in New Zealand in 1996), S. Nchanga (3 human isolates since it was first confirmed in New Zealand in 2005).