Why is Covid-19 killing so (comparatively) few in Africa?
Experts say factors such as a younger population and being behind the wave could be our saving graces
Covid-19 is killing fewer people than expected in Africa.
“About 14,000 people have unfortunately died on the continent and we have a case fatality rate of 2.2%,” the head of the Africa Centres for Disease Control and Prevention (CDC), Dr John Nkengasong, said on Thursday.
This is lower than global trends, particularly in the top 10 countries worst affected by coronavirus: the observed case fatality rate for the UK is about 15% and Mexico is next at about 11.6%.
The case fatality rate in the US is 3.9% and in Brazil 3.8%, according to Johns Hopkins University’s mortality analyses.
SA has a case fatality rate of about two percent, said the interim director of the National Institute for Communicable Diseases (NICD), Prof Lynn Morris, who was invited to speak at the Africa CDC weekly briefing.
“One of the things characterising the epidemic in SA, which is true in many countries (on the continent), is the low fatality rate relative to the case rate.
“In SA, the current death rate varies at about two percent. This is considerably lower than many countries in Europe,” said Morris.
“The short answer is, we don’t know. As a continent we really need to understand this better,” said Morris.
“There are some hypotheses. The younger population in SA and in Africa in general is certainly one potential factor.
“In terms of the global pandemic, Africa is behind the wave and we’ve had the opportunity to implement some of the clinical interventions or improvements, including dexamethasone, and this may have played a role.”
These and other hypotheses need to be investigated to find answers, Morris said.
“It is important for us to understand (the fatality rate) so that when Covid takes off in other parts of the country we can plan correctly,” said Morris.
Many predictions and models based on global numbers and trends have so far proved unreliable.
“The focus should be on trying to keep these low death rates,” said Morris, thanking health-care workers on the front line for the role they play in saving lives.
We have always said we have a delayed epidemic and we must be careful not to interpret the low numbers to mean the continent has been spared.Dr John Nkengasong
As a continent, Africa is only about six months into the pandemic and Nkengasong said everyone was still learning about it.
“We have always said we have a delayed epidemic and we must be careful not to interpret the low numbers to mean the continent has been spared,” he said. “(Coronavirus) has seeded into the communities and is spreading rapidly.”
Nkengasong said new cases had risen 23% from last week to Thursday, with about 119,000 new cases. That’s an average of about 17,000 new cases a day, compared with 14,000 a day last week.
The increase in testing — up 11% from the previous week — increases the detection of new cases. About 6.5 million coronavirus tests have been conducted on the continent to date.
“SA has done more than 2.2 million tests, in the private and public sectors, and this has contributed a lot to the tracking and tracing system in some provinces,” said Morris.
SA has nearly half (48%) of the total number of cases on the continent – 644,205 by Thursday.
Morris said: “We only have behavioural interventions to try to limit the spread (of the virus) and what we really need is a preventive vaccine to get on top of this epidemic.”
She said the high rate of enrolment in SA’s first clinical Covid-19 vaccine trial (the international Ox1Cov-19 vaccine VIDA-trial) means scientists could get the results of the Phase I safety trial earlier than expected.
More than 30 Covid-19 vaccines are now being tested in clinical trials, out of about 150 in development.
An HIV vaccine specialist and virologist, Morris said this Covid-19 vaccine development was still in the early stages and there was “not any solid data yet” about efficacy, despite optimism about it.
“Vaccines have a high rate of failure ... we do not yet have a vaccine against HIV. We are optimistic that coronavirus is genetically stable, unlike HIV, which changes all the time,” said Morris.
We are optimistic that coronavirus is genetically stable, unlike HIV, which changes all the time.Prof Lynn Morris
The vaccine candidates being tested have “induced the right kind of immune response, but we need evidence and data to know where this is headed”, she added.
Meanwhile, the Africa CDC head said: “We are calling on all countries in Africa to have a policy of universal masking — to all wear masks in public places. There is plenty of evidence to show this decreases transmission.”
He urged member states to follow the example of countries such as Japan, Singapore, New Zealand and Mauritius, which successfully implemented measures, including masking, sanitising, testing and contact tracing, to fight the virus and win this round of the battle.
“If these measures are not implemented, we are in for a very, very long haul,” said Nkengasong.