JOHANNESBURG, South Africa
South Africa is now recording new coronavirus cases every day at a rate higher than any other country in the world when reported Covid-19 infections are compared by population size.
On
average for the week of 6 to 13 July, the country recorded 19.6 cases per 100
000 people – a growth rate higher than every other country in the world
currently.
The calculation
is made by taking the daily case increases over time and finding the proportion
per 100 000 people of the population these daily new cases represent. To make
sense of this visually, this daily case increase per 100 000 people is then
placed on a seven-day rolling average scale, as seen in the graph below.
It is clear from
the graph that on this seven-day rolling average, only Peru has historically
exceeded an average rise of more than 20 cases per 100 000 people a day. The
daily increase rate in Peru, while still significant, has declined steeply in
recent weeks when compared with other countries.
Comparatively, SA is testing at a
lower rate than other countries – which gives rise to fears there are a
high number of cases that remain undetected. When testing per day is mapped on
a similar seven-day average of tests per 100 000 people, it is clear that
testing in South Africa is outpacing many of the "top 10" countries
with the highest cumulative infections, but lags behind countries that have
found a similar number of cases, such as the United Kingdom.
On
Tuesday, SA also overtook the UK in terms of cumulative confirmed Covid-19
cases with a reported 298 292 cases, which means it is now 8th in the world in
terms of the most cases recorded over time.
As
of Tuesday, UK health authorities reported 291 393 confirmed cases.
The
surge in cases in SA in July has been driven by significant increases in cases
in Gauteng, which became the first province to record more than 100 000
coronavirus cases at a case doubling rate hovering around 10 days, compared
with more than 20 days in the Western Cape, where the majority of the country's
cases were initially found.
Low testing numbers in SA mean a
high number of cases could potentially be going undetected. As of Tuesday
Health Minister Zweli Mkhize reported that 2.2 million tests had been conducted
for Covid-19, translating into roughly 3 864 tests per 100 000 people –
lower than Chile, the US, the UK and Russia.
As
of Tuesday, SA had conducted 5 million tests less than the UK, but found more
cases.
While the overall testing
strategy for South Africa remains unclear, in June Mkhize confirmed to News24
that the country was moving toward a more targeted testing strategy which would
focus on hospitalised patients and close contacts of confirmed cases, as well
as healthcare workers.
This means that testing is not giving a clear picture of the actual spread of Covid-19, and scientists generally accept there is a high rate of under detection of cases which is yet to be quantified.
Stat News reported in early June
a top World Health Organisation (WHO) official clarified that scientists had not
determined yet at what rate asymptomatic cases spread the virus just
one day after suggesting that such spread is "very rare".
The
clarification came after the WHO's "original comments incited strong
pushback from outside public health experts, who suggested the agency had
erred, or at least miscommunicated, when it said people who didn't show
symptoms were unlikely to spread the virus", Stat News reported.
A recent study published by the National Academy of Sciences by scientists
in the US found "that silent disease transmission during
the presymptomatic and asymptomatic stages are responsible for more than 50% of
the overall attack rate in Covid-19 outbreaks".
The
latest available modelling by the SA Covid-19 Modelling Consortium also
estimates a high level of undetected cases – possibly 3 million cases being
detected out of 12 million infections over time.
But
the modellers have repeatedly warned the estimates should be interpreted with
caution due to a "high degree of uncertainty" surrounding reported
coronavirus data.
Access
to detailed Covid-19 data collected by the Department of Health has been
severely restricted and only basic data is made public, but based on available
public data the increase in the percentage of tests coming back as positive for
Covid-19 has also steadily increased in recent weeks.
The South African Health Products
Regulatory Authority recently approved the country's first serological rapid
test kit, which could significantly amplify efforts to find Covid-19 cases.
But
crucially, the country has recorded 4 346 deaths compared with the UK's 44 915
deaths (as of 14 July) and has one of the lowest crude mortality rates
globally.
The explanations offered by
scientists as to why the death rate is so low compared
with European countries has varied – but a leading theory is
that Covid-19 is yet to spread to vulnerable communities where access to
healthcare and living conditions do not provide opportunity for social
distancing.
South
Africa also has a comparatively young population, and death trends observed in
other countries and here show older people are at higher risk of falling
seriously ill from the Covid-19 disease.
On Sunday, President Cyril Ramaphosa urged the country to behave responsibly and prove models wrong that estimated the country would experience 40 000 deaths from Covid-19 over time. – News24
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