Goal should be to keep new infections relatively low

Of the options, right, the third one – allowing infections to rise to achieve herd immunity – is ill-advised, at least for now.

To achieve herd immunity over a period of just two years, assuming that only 60% of the population would need to have achieved immunity, would require roughly 51 000 new infections per day.

At these levels it can be expected that more than 2 500 people will require hospitalisation each day and that approximately 500 will require intensive care, most of whom would die.

This option can also be rejected on rational grounds. If it is possible to maintain the rate at about one over an extended period using public health interventions without undue economic hardship, it makes sense to manage a lower rather than a higher and more risky level of infections.

This leaves options 1 and 2. The choice comes down to what is achievable with South Africa’s public health and economic capacities and capabilities. Both options, however, must be compatible with the maintenance of a functioning economy.

A generalised lockdown is unlikely to succeed as a preventive option in the South African context.

As a result, much depends on whether more focused public health measures – such as testing and contact tracing, social distancing, employer health protocols, generalised requirements to wear masks and border management – are sufficient to hold the rate at one or below one.

If these interventions can’t be relied on, the outlook for SA would be bleak, as a runaway epidemic would be more, rather than less, probable. The de facto consequence would be option 3.

But it’s plausible that a strategy that is able to maintain a low level of daily new infections over a two-year period could hold out the opportunity for disease elimination if public health prevention improves over time.

For instance, while significant constraints exist to scale up testing in the short term, these can reasonably be expected to lift progressively over a 12-month period.

Similarly, it is not unreasonable to expect the specificity and speed of contact tracing and quarantining to improve over time. It is also common sense for testing priority to be given to communities where transmission risks are highest – such as townships and informal settlements.

The direct costs of many of these interventions may appear large. But when compared to the indiscriminate impact of a general lockdown, the additional resources required pale into insignificance.

Conclusion

The current best option is for government to pursue option 2 – keep new infections relatively low, but accept that the epidemic will continue until a vaccine or some other treatment becomes available to allow for societal immunity. With a continuous expansion of key public health interventions, such as testing, tracing and quarantining, this approach also offers some hope of achieving option 1.