Epidemiologists are worriers. We like to think of ourselves as warriors, of course, but if you spend your professional time counting illness and deaths you worry a lot about diseases like Covid-19. Many of us knew another pandemic was likely. We tracked the outbreaks of diseases like Ebola, SARS and MERS, anxiously wondering if this was The One. Facing the reality of a worldwide pandemic brings into sharp focus everything we don’t know about this disease and how the pandemic will evolve over the next 6-12 months. 

If 20% of SA's adult population gets infected, and 1-5% of these require ventilation, we could need over 180 000 ICU beds [Image: crowf/Freepik]


For example, how many people are actually being infected, how long will immunity to the virus last, how many people need to be immune to slow down the spread, will it show a seasonal pattern, will we find an effective vaccine? The list could go on.

It is for those reasons that I was worried about the lockdown in South Africa. Mainly, was it too early? What if the virus spreads more easily in winter, still a few months away? So what if we lockdown for three weeks now, slow the spread of the virus, only to be overwhelmed in June and July.

But, although we are only at the beginning of the lockdown, I now see it as inevitable. We had to slow down this epidemic. Not stop it, no, just buy ourselves some time. After all, South Africa has a population of 57 million people. If 20% of the adult population gets infected, and 1-5% of these require ventilation (depending on age), we could still need over 180,000 ICU beds for all the people who might need them. South Africa has just over 7,000 ICU beds in both the public and private sectors, as described here.

But this lockdown will be an effective strategy only if we use this time to put in place the key features of an effective response. This would significantly reduce the number of people who could require ICU care over the next six months. I have listed below the six key features of an effective response, gathered from our best current understanding.

1.    Testing (and more testing)

There is no alternative to finding and isolating all infectious people. This has been the real lesson from all the countries that have managed to control this epidemic, like China and South Korea.  After all, we have no vaccine and no specific anti-viral treatment, so we need to reduce contact between infected and uninfected people. The lockdowns buy you time and this time needs to be used to make sure we can test all symptomatic people and prepare to isolate people who test positive for the virus. If they cannot isolate themselves – as many will be unable to do in South Africa and also many in poor countries – we need to have places for people to be housed while they recover, if they do not require hospital care. It is fortunate for South Africa that a variety of simpler, quicker tests are coming onto the market and hopefully these will be available soon.

2.    Contact Tracing

To contain this epidemic we need to trace, isolate and test all the contacts of people who are infected. By now most people have seen the simulations of how a virus spreads in a population, based on its R0, which is the average number that an infected person will go on to infect. We don’t know the exact R0 of SARS-CoV-2, the virus that causes Covid-19. But we think it is between 2 and 2.5, which means each infected person will infect two to three other people. This could be an underestimate in crowded cities and informal settlements.  The only way to slow down the spread of this virus is to identify all the contacts of cases and get them into isolation for 14 days, or until they are not infectious themselves. This has been done successfully in places like South Korea and China by using sophisticated technology, including mobile identification to track people and their movements in the days before their diagnosis.

3.    Protect Health Workers

Health workers are alarmingly susceptible to this disease and over the last three months, we have heard devastating stories of doctors, nurses and other health workers becoming ill and dying from Covid-19. In Italy, as of writing, 51 doctors have died. Besides the obvious tragedy of losing precious lives, along with all the other victims of this illness, this damages the very services we need in place to treat people who become severely ill from this virus. Priority has to be given to securing the appropriate protective equipment to protect health workers, ensure they are trained in its use and that this personal protective equipment (PPE) is available for use wherever health and other service workers will be working with people with this disease.

4.    Prepare Health Services

In places like Wuhan, Lombardy and, increasingly, other cities around the world, health services are rapidly being stretched to breaking point. This is particularly the case of intensive care units (ICU) where patients are ventilated. As the name suggests, these are parts of the health system that often require the highest level of resourcing and where patient care is most intense. We don’t yet know what percentage of infected people require such intensive care and ventilation, but real-life experience is showing us that it is well beyond current capacity in almost all countries. This will be grossly exacerbated in developing countries, where ICU capacity is far more limited. In these countries, there is a real possibility that we will see much higher mortality, and among younger people, as the virus spreads. In South Africa, where we have over seven million people living with HIV, we have to prepare for the worst. All countries need to use this lockdown time to prepare their health services for this potential tsunami of patients in severe respiratory distress. Special wards need to be prepared and staffing needs to be organised. Health workers will need psychological support and counselling.

5.    Set Targets – 2 90s and a 100

This epidemic has come at us so quickly that most countries are just scrambling to catch up. Setting ambitious targets has increasingly helped to mobilise people and resources for other epidemics, like HIV and TB. I would suggest the following targets for Covid-19:

·      90% of symptomatic people get tested and know their results

·      90% of their contacts are identified and isolated

·      100% of health workers have access to the PPE which they need

6.    Protect Human Rights

There is a real threat that our pandemic response can infringe on people’s individual rights. This can include rights to privacy, autonomy, freedom of movement, and others. While restrictions can be necessary during a disaster, which Covid-19 definitely is, the risk is that governments leave these measures in place for their own purposes after this crisis has passed. We should use this time to put in place oversight mechanisms and ensure that all the emergency measures we use that infringe on individual rights are used only to fight this disease and are removed as early as possible.

Humanity has repeatedly faced epidemic diseases, the causes of which are complex and deserve great scrutiny. But for now, let’s use the breathing space we have bought ourselves at great cost to make sure we are suitably prepared for the next phases of this fight.

Thanks to the public health experts, many of whose ideas I have borrowed from. To name just a few – Devi Sridhar, Anthony Costello, Marc Lipsitch and many more. And please continue to follow the WHO, CDC and other reliable sources of news about this epidemic.


– Saul Johnson is Head of Health Practice at Genesis Analytics