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Infectious Diseases

01 October 2020

‘Our choices will determine what’s to come’, says SA medical expert on potential second wave

South African epidemiologist Professor Alex Welte warns that there is still a chance of SA experiencing a ‘second wave’, but that the right behaviour change can avert it.

  • A second wave of Covid-19 infections in SA is still possible, experts warn
  • Certain countries in Europe are already experiencing a fresh spike in cases
  • An SA epidemiologist explains that our behaviour and implementing NPIs can greatly help to avoid another wave 

Despite South Africa moving to alert Level 1 lockdown in September, and being the country with the 10th highest recovery rate (90%) in the world, experts are warning that there is still the potential of a second wave of Covid-19 infections – but that a behaviour change can avert it from happening.

Speaking at a virtual webinar by MTN South Africa on 30 September, Professor Alex Welte, an epidemiologist at the South African Centre for Epidemiological Modelling and Analysis, University of Stellenbosch, shed light on where we are, and what needs to be done going forward.

Still many unanswered questions

When we look at what’s actually happening in the Covid-19 epidemic and what processes are available to us, there are a number of things to consider, explained Welte, including that the virus mainly spreads via respiratory droplets, although the jury is still out on other ways of transmission, such as aerosol transmission.

“Where exactly Covid-19 is on the spectrum is still controversial, but we have to be careful. We can’t have the final answer on what the correct restrictive measures are to impose, but beneath all this complexity, there are sensible questions we can all engage with,” said Welte. 

What we know and where we are right now

“We do know that having the virus once gives you immunity for a good period of time. If that were not the case, there would have been a lot of people who had it multiple times,” commented Welte, adding that having contracted the virus twice is by far the exception and not the norm, although scientists are still trying to determine how long the immunity lasts.

In terms of where we are at now, Welte explained that we’ve got to look at the bigger picture.

“What we do know is that we’ve had major waves of death and infection from July stretching into August. And we are over the worst of that. If you ask ‘what’s coming?’ – more of the same is coming, I’m sorry to say. And hopefully there is long-term immunity, but we don’t know that yet.”

A second wave is difficult to predict, said Welte, and we can’t tell whether it might arrive in November this year or in February next year, nor can we determine whether it’s going to be a bigger or smaller wave than the first one.

“I would hope for a smaller one as it’s easier to control. And that would be because we have some pre-existing immunity.

“But the precedent is not brilliant. If we look at Europe (and although they’re not exactly like us as there are some important differences), they’re all having trouble now with second waves – and third waves, in some cases – so immunity doesn’t last forever… That should be a sobering lesson to us,” he added.

Getting back to ‘normal life’ during the epidemic 

While the first wave has passed in SA and things are slowly returning to normal, it does increase the basic risk of a second wave as there is greater opportunity for people to come into contact with droplets that infected people are spewing into the air, said Welte.

“We cannot hope that somehow it’s magically going to go away. We’re becoming more relaxed every day because we’re tired of sitting at home, or whatever the case may be... and that’s understandable, but that brings risks.

“The virus doesn’t get tired; it’s an utterly remorseless set of chemicals, and we don’t get a break. So I do worry that more is coming, and just how much is coming is under our control, to some extent.”

‘The future really is in our hands’

This is where our choices really matter, said Welte, “... where mask-wearing, avoiding the hand-shaking and parties really makes the difference.

“The future is really in our hands; how sensible we are and how disciplined we can be. I’m not saying it’s easy, but our choices will determine what’s to come. It’s not something to analyse and predict – it’s more about actions to take and to influence that in a positive way.”

This all plays into what we can do, and it’s all the basics of non-pharmaceutical interventions (NPIs), he added, including maintaining physical distancing and good hand hygiene; wearing face masks; increasing ventilation; and avoiding crowding, among other things. 

We must accept a resurgence could happen in SA

That a Covid-19 resurgence could happen is not some sort of theoretical statement, said Welte: “It’s already happening in a lot of places, and in places that were on a similar trajectory to us: they had some outbreaks; they stayed at home; they started wearing masks, and those peaks came and went – the ICU’s emptied out – and now it’s all happening again. And that’s evidence.

“There are people panicking in many countries because they thought they were over it and they’re not. We should not believe that we are the magical rainbow nation that will have it better than everybody else. We have to accept that we are pretty normal.”

And while many people still express doubt about these countermeasures implemented to control the spread of the virus, it really does make a huge difference, Welte said.

“The virus obeys the laws of physics; it doesn’t have any willpower, but we have a lot of agency. The rules are the rules: the droplets are there. We have to believe the science.”