Highlights
- Since the last Situation Report, 24 new laboratory-confirmed measles cases have been detected across the country according to data up until 21 January (mid-week-03, 2023). This brings the number of measles cases in South Africa since epidemiological week 40 of 2022 to 421.
- In outbreak-affected provinces, a total of 406 measles cases have been detected from week 40 of 2022 until mid-week 03 of 2023. In week 02, 2023, 16 cases were diagnosed, whilst to date, (mid-week through week 03), 14 cases have been identified.
- The percentage testing positive midway through epidemiological week 03 has risen to 14% (14 positive/103 specimens tested) from a low of 9% during epidemiological week 02 (16 positive / 186 tested).
- In week 03, 2023, the largest number of cases are from Gauteng Province, with 6 cases arising from clinics within a 2km radius in Ekurhuleni (3 from Daveyton Main clinic, two from Philip Moyo Clinic, one from Crystal Park Clinic and one from Bertha Nxowa Hospital). This focus of infection requires immediate action including a vaccination campaign to prevent exponential spread here, and within and beyond the province over the next few weeks.
- The age distribution and origin of cases remain largely unchanged with the majority of measles cases in outbreak-affected provinces being among the 5-9-year age group (160/406, 39%), and the highest proportion of cases arising from hospitals as opposed to primary health clinics in the under-1 year age group (15/27, 59%). However, significant numbers of cases in the 10-14 year age group continue to occur (65/406, 16%), justifying the need for a vaccination campaign to include this age group.
- Members of the public are urged to ensure their children are vaccinated against measles.
Outbreak overview
From epidemiological week 40, 2022 (ending 8 October 2022) to mid-week 03, 2023 (ending 21 January 2023) the NICD has tested 2750[1] serum samples for measles of which 421 (15,3%) were confirmed measles cases (Table 1). The number of samples submitted, number and % tested positive are shown in Figure 1. From epidemiological week 40 of 2022 to week 03 of 2023, 406 laboratory-confirmed cases were reported from five provinces with declared measles outbreaks in Limpopo (149 cases), Mpumalanga (81 cases), North West (133 cases), Gauteng (25 cases), and Free State (18 cases) (Table 2). The geographical distribution of cases across South Africa from week 40 of 2022 until mid-week 03 of 2023 is shown in Figure 2he number of cases continues to increase daily as blood and throat swabs are submitted to the NICD for measles serology and PCR testing.
[1] This number has been revised downward following review and cleaning of data
Figure 1. The number of serum samples submitted to the NICD for measles, week 40 2022, until midweek 3, 2023 and the number (dark green) and % tested positive (red line), by epidemiological week.
Figure 2. Distribution of laboratory-confirmed measles cases by testing site (red dots – the size of the dot indicates the number of cases from that facility) and district of South Africa (deepening colour of blue indicates the total number of cases by sub-district), from week 40 to mid-week 03, 2023.
Table 1. Cases of laboratory-confirmed measles tested by the NICD from all provinces in South Africa from epidemiological week 40, 2022 to mid-week 03, 2023. Outbreak-associated cases are contained within the red bordered cells* (EC=Eastern Cape; FS=Free State; GP=Gauteng; KZN=KwaZulu-Natal; LP=Limpopo; MP=Mpumalanga NW=North West; NC=Northern Cape). * A measles outbreak is classified as three or more confirmed laboratory measles cases reported within 30 days of the onset of disease, in a district.