The number of coronavirus tests done in every province in South Africa

New data presented by the National Health Laboratory Service (NHLS) reveals how many Covid-19 tests have been conducted in South Africa across all provinces to date – and what proportion have come out positive.

Across the country, the NHLS’s data (to 28 May) shows that over 680,000 tests have been processed in the country.

Counter to claims made about the Western Cape having the highest number of tests done, the NHLS showed that Gauteng has so far conducted the most tests, accounting for approximately a third of the total.

This is followed by the Western Cape with 23% and Kwa-Zulu Natal, with 17%.

While accounting for 23% of overall tests, the Western Cape has two thirds of all coronavirus cases in the country. South Africa’s positive test rate averages 4.6% – but the Western Cape’s positive rate is almost three times higher at 12.7%.

According to chair of the coronvirus advisory panel, professor Abdool Salim Karim, the data shows how much of an outlier the Western Cape is in the overall infection trend in the country.

More specifically, he noted that the proportion of positive cases has remained stable across all other provinces as testing increases (sitting in a range of 1.1% to 4.6% week on week) – but in the Western Cape, the proportion has climbed as more tests have been conducted.

Another outlying indicator is in how quickly the number of cases is doubling. Before lockdown, the time taken for cases to double in South Africa was two days.

During lockdown, this slowed to 15 days – and since easing to lockdown level 3, this has quickened to 12 days.

This same trend has been seen in all provinces except the Western Cape, he said, where days to doubling started at two days, jumped to 18, and now sits at nine days.

Karim said that the Western Cape serves as an early indication of what lies ahead for other provinces in the country.

He said that the province was able to identify hotspot areas, and determine the cause of the rapid spreading – and from there has been able to develop plans to intervene.

“The province is now dealing with the spread on a very localised level,” Karim said. This, he added, is the next phase of the country’s response plan – finding the hotspots and dealing with them in a very directed way.

“It’s about finding the flames before they turn into a raging fire,” he said.