Monthly Notifiable Disease Surveillance Report - Sep 2021

COVID-19: There were 656 cases of COVID-19 reported in September 2021 (654 confirmed and 2 probable), compared with 95 cases for the same month in 2020. The vast majority (591, 90.1%) were community cases, 64 (9.8%) were imported cases in managed isolation/quarantine (MIQ) facilities, and one was an MIQ worker. Fifty-six cases (8.5%) were hospitalised, and no deaths were reported. More information can be found on the ESR COVID-19 dashboard.

Invasive pneumococcal disease: There were 30 cases of invasive pneumococcal disease reported in September 2021, compared with 22 for the same month in 2020. All 30 cases were laboratory confirmed. A serotype was identified in 29 (96.7%) cases, and the most common serotype was 19A, accounting for 10 (34.4%) cases, including two cases aged under 1 year. Two deaths were reported; one in an infant aged under 1 year and one in an adult aged 50-59 years. The infant had received two doses of PCV10 and their infection was due to serotype 19A.

Meningococcal disease: There were five cases of meningococcal disease reported in September 2021, compared with one case for the same month in 2020. Four cases were in children aged under 10 years and one was an adult aged 20-29 years. All five cases were of Māori ethnicity. The strain type was identified in four cases and all were group B: three were B:P1.7-12,14 and one was B:P1.22,14. The three cases with the same strain were from three separate DHBs.

Shiga toxin-producing Escherichia coli (STEC) infection: There were 89 cases of Shiga toxin-producing Escherichia coli (STEC) infection (82 confirmed and 7 under investigation) reported in September 2021, compared with 79 cases for the same month in 2020. Over a quarter (23/82) of the confirmed cases were aged under 5 years. Seven cases were hospitalised and one case of haemolytic uraemic syndrome (HUS) was reported. The serotype was identified for 58 cases and 41 (70.7%) were non-O157.

OUTBREAKS

Cryptosporidiosis: An outbreak of cryptosporidiosis involving six cases (4 confirmed and 2 probable) linked to consumption of raw milk was reported from Taranaki DHB in September 2021. All six cases had consumed raw milk from the same supplier. Cryptosporidium parvum subtype IIaA18G3R1 was identified from three of the four confirmed cases; the subtype for the remaining confirmed case was not able to be determined. The same subtype was also isolated from cases in a cryptosporidiosis outbreak linked to the same raw milk supplier in May 2021. An investigation by MPI confirmed that the raw milk supplier is meeting regulated control scheme requirements.

Legionellosis: An outbreak of legionellosis involving three residents of an aged residential care facility in Auckland was reported in September 2021. Cases were notified in January, August and September 2021. Legionella pneumophila was confirmed by urinary antigen test in all three cases, and two of the cases died. Investigations into possible environmental sources are continuing.

Respiratory illness: There were 11 respiratory illness outbreaks reported in September 2021, involving 145 cases. Three outbreaks were reported as influenza-like illness (ILI) and eight were reported as acute respiratory infection (ARI). Respiratory syncytial virus (RSV) was identified in five outbreaks, human metapneumovirus in one and coronavirus (not SARS-CoV-2) in one. No pathogen was identified in the remaining four ILI/ARI outbreaks. All 11 outbreaks were in long-term care facilities.