Establishment of outbreak thresholds for Hepatitis A in South Africa using laboratory surveillance, 2017–2020
Date
2021
Journal Title
Journal ISSN
Volume Title
Publisher
MDPI
Abstract
As South Africa transitions from endemic to intermediate endemicity, hepatitis A surveillance needs strengthening to monitor trends in disease incidence and to identify outbreaks. We used
passive laboratory-based surveillance data from the National Health Laboratory Services to calculate
national hepatitis A incidence and to establish thresholds for outbreaks. Incidence was calculated by
age and geographic location. The static threshold used two or three standard deviations (SDs) above
the mean hepatitis A incidence in 2017–2019, and a cumulative summation (CuSum2) threshold used
three SDs above the mean of the preceding seven months. These thresholds were applied to hepatitis
A data for 2020. From 2017 to 2020, the mean incidence of hepatitis A IgM was 4.06/100,000 and
ranged from 4.23 to 4.85/100,000 per year. Hepatitis A incidence was highest in the Western Cape
province (WCP) (7.00–10.92/100,000 per year). The highest incidence was in the 1–9-year-olds. The
incidence of hepatitis A in 2020 exceeded the static threshold in two districts of the WCP: Cape
Winelands in January and Overberg district in August. The provincial incidence did not exceed the
static and CuSum2 thresholds. District-level analysis using either threshold was sensitive enough to
monitor trends and to alert district health authorities, allowing early outbreak responses.
Description
CITATION: Prabdial-Sing, N. et al. 2021. Establishment of outbreak thresholds for Hepatitis A in South Africa using laboratory surveillance, 2017–2020. Viruses, 13:2470, doi:10.3390/v13122470.
The original publication is available at https://www.mdpi.com
The original publication is available at https://www.mdpi.com
Keywords
Hepatitis A, , ,
Citation
Prabdial-Sing, N. et al. 2021. Establishment of outbreak thresholds for Hepatitis A in South Africa using laboratory surveillance, 2017–2020. Viruses, 13:2470, doi:10.3390/v13122470.