Leading South African doctors advising the Government's Covid-19 response have called for quarantine and contact tracing to be stopped immediately, saying the measures are of "negligible public health benefit".
The Ministerial Advisory Committee (MAC) on Covid-19, co-chaired by Professors Koleka Mlisana and Marian Jacobs, wrote to South African Health Minister Joe Phaahla on Thursday to argue that existing quarantine and contact tracing protocols were "outdated" and no longer effective containment measures.
The MAC pointed out that only a very small proportion of Covid-19 cases were detected through testing, as up to 84 per cent of cases were estimated to be asymptomatic.
"It stands to reason that if the vast majority of cases are not diagnosed, then the vast majority of case contacts are also not diagnosed," Mlisana and Jacobs wrote.
"This means that quarantining and contact tracing are of negligible public health benefit in the South African setting."
South Africa introduced a 14-day quarantine period for "high risk" contacts of Covid-19 patients in early 2020. This was later reduced to 10 days.
"Since then, several changes to the Covid-19 situation have occurred," they wrote.
"The proportion of people with immunity to Covid-19 (from infection and/or vaccination) has risen substantially, exceeding 60-80 per cent in several serosurveys.
"We have learned more about the manner in which Covid-19 is spread, and also now have to contend with variants of concern whose epidemiology differs from that of the ancestral strains of Sars-Cov-2.
"Crucially, it appears that efforts to eliminate and/or contain the virus are not likely to be successful. Therefore, it is critical that the role of containment efforts like quarantine and contact tracing is re-evaluated."
The MAC also said the definition of "high risk" contact – those who "had face-to-face contact or [were] in a closed space with a Covid-19 case for at least 15 minutes" – was "based on an outdated understanding of the transmission dynamics" of the virus.
"The definition concentrates on droplet spread while ignoring aerosol spread, which can occur over distances greater than 1-1.5 metres, and also does not require as close a temporal association with the index case," they wrote.
"In addition, it ignores the increased intrinsic transmissibility of subsequent variants of concern compared to the ancestral strain, as well as the fact that pre-existing immunity (from vaccination and/or natural infection) further changes the transmission dynamics."
The experts said quarantining was not feasible in many social settings, and had a "substantial economic and social burden".
Those include "significantly depleting" staffing levels at healthcare facilities and other frontline roles such as police, and "significantly reducing economic and governmental activities due to high levels of staff absenteeism".
"We propose that quarantining be discontinued with immediate effect for contacts of cases of Covid-19," they wrote.
"This applies equally to vaccinated and non-vaccinated contacts. No testing for Covid-19 is required irrespective of the exposure risk, unless the contact becomes symptomatic.
"We further propose that contact tracing be stopped.
"Since quarantining of contacts of cases no longer serves a public health role, identifying contacts of Covid-19 cases equally serves very little role. In addition, contact tracing is impractical once the Covid-19 caseload rises, and is extremely burdensome in its use of human and financial resources."
The letter came as Phaahla announced that South Africa would remain under modified "level one" lockdown restrictions over Christmas, amid concerns over the spread of the Omicron variant, News24 reported.
Last month, the South African doctor who first raised the alarm about Omicron expressed surprise at the "extreme response" by world governments including the UK.
Dr Angelique Coetzee, a GP and chairwoman of the South African Medical Association, stressed that "nothing I have seen about this new variant warrants the extreme action the UK government has taken in response to it".
"In South Africa, we've retained a sense of perspective," she wrote in an opinion piece for the Daily Mail on November 30.