COVID‐19 in one region of New Zealand: a descriptive epidemiological study. (3rd October 2022)

• Record Type: Journal Article
• Authors: Hammond, Vanessa; Butchard, Michael; Stablein, Hohepa; Jack, Susan
• Is Part Of: Australian and New Zealand journal of public health. Volume 46:Number 6(2022)
• Page Start: 745
• Page End: 750
• Publication Date: 2022-10-03
• Subjects: COVID‐19 -- epidemiology -- New Zealand; Public health -- Australia -- Periodicals; Public health -- New Zealand -- Periodicals; Medical care -- Australia -- Periodicals; Medical care -- New Zealand -- Periodicals; 362.10993
• DOI: 10.1111/1753-6405.13305
• Languages: English
• ISSNs: 1326-0200

Abstract

Abstract: Objective : To describe the epidemiology of COVID‐19 in one region of New Zealand in the context of the national lockdown and provide a reference for comparing infection dynamics and control measures between SARS‐Cov‐2 strains. Methods : Epidemiological linking and analysis of COVID‐19 cases and their close contacts residing in the geographical area served by the Southern District Health Board (SDHB). Results : From 13 March to 5 April 5 2020, 186 cases were laboratory‐confirmed with wild‐type Sars‐Cov‐2 in SDHB. Overall, 35·1% of cases were attributable to household transmission, 27·0% to non‐household, 25·4% to overseas travel and 12·4% had no known epidemiological links. The highest secondary attack rate was observed in households during lockdown (15·3%, 95%CI 10·4–21·5). The mean serial interval in 50 exclusive infector‐infectee pairs was 4·0 days (95%CI 3·2–4·7days), and the mean incubation period was 3.4 days (95%CI 2·7–4·2). Conclusions : The SARS‐CoV‐2 incubation period may be shorter than early estimates that were limited by uncertainties in exposure history or small sample sizes. Implications for public health : The continuation of household transmission during lockdown highlights the need for effective home‐based quarantine guidance. Our findings of a short incubation period highlight the need to contact trace and isolate as rapidly as possible.