Lockdown necessary but more testing crucial

It is easy to throw stones at idiosyncratic bits of South Africa’s COVID-19 lockdown programme, but it was the right move, said the University of Cape Town’s Professor Robin Wood, at a MedicalBrief webinar. Wood repeatedly stressed the need for more testing.

The webinar on Tuesday 7 April, titled “COVID-19 transmission: Aerobiology research implications for hospitals, medical practices and everyday life”, screened an interview with Wood by MedicalBrief Managing Editor William Saunderson-Meyer, followed by questions. 

Wood spoke, among other things, about the pandemic in South Africa, government actions, and whether high HIV and TB prevalence might make the country particularly vulnerable to COVID-19, or whether – as some have suggested – people on antiretrovirals might be less vulnerable.

Coronavirus and South Africa

Asked how COVID-19 might play out in South Africa, and whether there are things that should be being done but are not, Wood’s main concern was that not enough testing is being done. There are good reasons and nobody to point fingers at, but testing is an urgent need, he says.

There are two components to COVID-19 action advice. “One is separating people and decreasing the number of people you meet, which is obviously social distancing. The other is the efficiency of transmission – trying to decrease that using the other methods.”

“My highest priority is to protect the elderly.”

In principle, the government has done the right thing by implementing a lockdown. Even though some things have not been properly thought through, such as the secondary consequences of laying people off and the pre-lockdown wave of possibly infected young people returning to rural areas.

This reminded Wood of the 1918 Spanish flu pandemic: “We had double the mortality rate that happened anywhere else because we disseminated the virus very rapidly. I think we should have protected rural areas from the epidemic in the cities.”

On the positive side, South Africa has a young population, which “might reduce the impact of the virus, along with other factors”. But Wood is concerned about the effectiveness of distancing strategies for people living in very poor conditions. This should be a focus.

“My highest priority is to protect the elderly.” Older people in rural areas should have been given supplies and support, along with help for people in old age homes.

The COVID-19 death rate rises above the age of 60 to the 80s, “where it really takes off. The death rate is related to age factors and also to the availability of health care and the overwhelming of health care systems,” says Wood.

“We have to protect our health care system, because it is going to be stretched. We are a middle-income country, so we have to preserve our resources and our medical staff are a particularly important resource.” 

One reason why distancing strategies are being used, Wood continues, is lack of understanding of COVID-19. “We can’t identify the sick and the transmitters, so therefore we take the whole population and try to apply something that seems like the intuitively right thing to do.”

While there have been difficult unforeseen circumstances, “having seen the explosion of the epidemic in other countries, it is not unreasonable for our leaders and politicians to do the fastest and easiest thing”. Retrospectively, it is also possible to argue what the smartest strategy would have been.

“The other thing is we are coming in to the flu season, in the next two or three months.”

With its relatively low number of infections and deaths, South Africa will only see in the coming weeks whether it will follow the trajectory of countries in the northern hemisphere.

But it would have been wrong not take action against the virus in the hope, for instance, that a hot climate would make a difference – although time will tell, says Wood. Scientists are looking at climate but the feeling is that COVID-19 is probably less impacted by environmental conditions than seasonal flu. “The other thing is we are coming in to the flu season, in the next two or three months.”

And while South Africa’s low death rate is good news, “experience of other countries would suggest we don’t take too much encouragement from that”. It is also likely there will be COVID deaths that are not counted. “We are not testing. Testing ability also changes that.”

A crucial need for more testing

Given the difficulty in identifying COVID-19 and its rapid unfolding, Wood continues, “we have to put major effort into testing”. A problem has been starting with very few tests, although there have been efforts to increase the number.

“Biotech companies around the world are also increasing the spectrum of tests.”

New research and information needs to be accessed quickly and applied straight away. “We’ve got a moving target and we’re trying to measure aspects of that moving target.”

“So this is a rapidly changing field and we need to get an idea of which tests are likely to be most successful, and then they need to be scaled up.

There are various means of testing via respiratory sampling, such as a throat or nasal swab or sputum. Testing is “changing by the minute”. There is a reasonably affordable serological test coming available from Abbot, looking for antibodies in the blood, “which is a totally different way of diagnosing the disease as opposed to respiratory samples”. There are probably also blood tests coming. “They’re all racing like mad to get these things out.”

The so-called PCR respiratory sampling test Wood’s research uses amplifies the RNA – the genetic code of the virus. The results take a long time, whereas blood and other tests may be able to provide answers in minutes, or at least an hour or two.

“So this is a rapidly changing field and we need to get an idea of which tests are likely to be most successful, and then they need to be scaled up.

“Because essentially we’ve got two ways of tackling this epidemic. One is social distancing and decreasing the efficiency of transmission between people, and the other is actually finding out who has got the disease – who is transmitting it, and targeting those people. That would probably be a combination of respiratory sampling and blood sampling,” Wood says.

COVID-19, TB and HIV

There have been conflicting arguments over whether COVID-19 makes South Africa, with its high HIV and TB prevalence, more or perhaps even less vulnerable. 

In Europe researchers did not find the presence of HIV to be a major factor in the pandemic, and there is not enough data to suggest antiretrovirals might be protective. “The feeling is that HIV individuals on appropriate antiretrovirals are not particularly at excessive risk compared to the rest of the population. Obviously, age is probably more important as your risk,” says Wood.

He is concerned about a possible link between COVID-19 and TB. “There was one bit of preliminary data from China to say that there may be some link between the two epidemics. Certainly I think it is an interesting area of research.”

Wood pointed out that TB and COVID present with almost identical symptoms. “There is fever, shortness of breath and body aches”. There is a need for tests appropriate for TB and appropriate for COVID-19. “People may have either-or, or both.”

It is important, Wood stresses, to see early on if there is a link between TB and COVID-19, because South Africa has the highest TB rates in the world. Importantly, the country is also in a good position to find answers.

Listen to a podcast of the MedicalBrief webinar question-and-answer session.