Wits experts suggest healthy people under 50 be allowed out of lockdown

With the country on the brink of an adjusted lockdown, two local experts have proposed a model in which healthy people below 50 would basically come out of lockdown, while those above 50 would remain at home.

It is a “hybrid” approach that falls somewhere between the hard lockdown we have seen so far, and the “herd immunity” approach adopted in the early days of the pandemic by the UK.

Fifty is the cut-off age between lower and higher mortality rates from infection, with the rates increasing with each decade of life above 50.

Wits University pulmonologist Prof Ismail Kalla and emergency medicine specialist Prof Abdullah Laher recently published a paper proposing this hybrid model in the Wits Journal of Clinical Medicine. It is entitled ‘Covid-19: The Concept of Herd Immunity — Is it a Strategy for SA?’

Britain’s “herd immunity” approach was announced by Boris Johnson in the early days of the global Covid-19 pandemic. It caused an outrage and was abandoned not long after.

Herd immunity happens when so many people in a community become immune to an infectious disease that it stops the disease from spreading.

The rationale behind the UK's herd immunity strategy, say Kall and Laher, was that by allowing “enough citizens who are going to get mild illness to become immune”, a national disaster may be averted.

The strategy proved disastrous, however. The failure was due to “high complication rates”, as well as the “short incubation period and lethality of Covid-19”.

“The initial UK strategy led to high rates of hospitalisation and intensive care unit admissions, thereby straining their current health service capacity beyond breaking point,” they said.

The country then went into lockdown. So far almost 26,000 Brits have died from Covid-19.

What’s missing from the approach is a vaccine.

“The concept of herd immunity was introduced with the widespread use of vaccines to protect against common but severely debilitating illnesses, such as smallpox and polio, which are spread by human contact,” said Kalla and Laher.

The idea is that some portion of the population will be immune, either to a vaccine or from previous infection.

But right now there is no vaccine for Covid-19 — and it’s still not clear whether infection causes immunity thereafter.

If the herd immunity attempt was a flop in the UK, in SA it could be even more disastrous.

“The crowding together of human beings, coupled with poor socioeconomic conditions, potentially places the African continent at particular risk for Covid-19,” said Kalla and Laher.

The health-care sector on the continent is also “overburdened ... due to infectious diseases such as tuberculosis (TB) and human immunodeficiency virus (HIV).”

In sharp contrast to the UK, SA went for one of the most extreme lockdowns in the world, with the military and police at hand to enforce it. While this has helped to curb the spread to some degree, it “may not be potentially sustainable in a South African economy nearing collapse”.

That’s why Kalla and Laher are scrutinising a hybrid model, saying that data on age groups and the virus provide a key to SA’s solution.

The burden of illness with Covid-19 “lies predominantly in the patient age groups above the fifth decade of life.”

The median age of the South African population is 27.6 years, with an average life expectancy of 64.8 years. This means “we have a much younger population compared to countries such as Spain, Italy and England, who have reported large numbers of Covid-19 related mortality”.

“In SA, a hybrid model could be considered, wherein young children, adolescents and adults under the age of 50 years, without any significant comorbidities, are allowed to return to schools or universities, and for employed adults to return to their places of employment,” said Kalla and Laher,

Those under 50 have had the mildest forms of the infection, the lowest mortality rate and, as the most economically productive, could help our “fragile economy” recover.

There are conditions, however. The model should be implemented only if all precautionary measures are in place, including “testing, surveillance, quarantine of infected individuals, social distancing, hygiene and very close support of the elderly at-risk population”. 

They say the phased approach could also help prevent a re-emergence.

They do not claim it is a perfect solution, however. One “potential limitation” is the unknown effect of Covid-19 on people living with HIV and TB.