Coronavirus: Scientists question Government policy on herd immunity

A former director at the World Health Organisation (WHO) has attacked the Government’s policy of using “herd immunity” as part of its strategy for tackling coronavirus.

Anthony Costello, professor of international child health and director of the University College London Institute for Global Health, questioned the tactics and argued they looked like they were against the policy set down by the World Health Organisation (WHO).

It comes after Sir Patrick Vallance, England’s chief scientific adviser, said the Government’s decision not to introduce tougher measures could have the benefit of creating “herd immunity” across the population as people become infected.

On Twitter, Prof Costello said: “Doesn’t this herd immunity strategy conflict with WHO policy? After the announcement of this being a pandemic, Dr Tedros, Director General WHO, said ‘The idea that countries should shift from containment to mitigation is wrong and dangerous’.”

Prof Costello said the Government was arguing that allowing a proportion of the population to catch the virus and gain immunity “will block a second peak in several months’ time”.

But he tweeted a series of questions showing scepticism for the policy, including: “Will it impair efforts to restrict the immediate epidemic, and cause more infections and deaths in the near term? Evidence suggests people shed virus early, and those without symptoms may cause substantial spread…”

He also questioned whether “coronavirus cause strong herd immunity or is it like flu where new strains emerge each year needing repeat vaccines? We have much to learn about Co-V immune responses.”

He said there was also an argument to see what happened in China, where the epidemic there has been contained “after 7 weeks of intense national effort”.

He added: “Without an all-out national mobilisation plan for social distancing, are the UK government behavioural and nudge strategies really evidence-based to flatten the peak? Or simply based on models?”

Prof Costello suggested that “shouldn’t we go all-out to snuff this UK epidemic out, with national mobilisation at all levels, using all possible preventive measures (whether evidence is strong, uncertain or weak) and worry about herd immunity when we have more evidence?”

He continued: “Vaccines are a safer way to develop herd immunity, without the risks associated with the disease itself. Is it ethical to adopt a policy that threatens immediate casualties on the basis of an uncertain future benefit?”

In a separate tweet, Devi Sridhar, professor of global public health at Edinburgh University, said: “Part of my job is speaking truth to power. And the UK govt is (in my view) getting it wrong.

“Other countries have shown speed is crucial. There is a middle path between complete shutdown & carrying on as normal.”

Jeremy Rossman, honorary senior lecturer in virology at the University of Kent, added: “A delay strategy when combined with surveillance and containment, as recommended by the WHO, could be very effective in combating the spread of COVID-19.

“Yet if we slow the spread of the virus but are relying on herd immunity to protect the most vulnerable people, we would still need 47 million people to be infected.”

However, Martin Hibberd, professor of emerging infectious disease at the London School of Hygiene and Tropical Medicine, said it was unclear how the UK policies will work compared to other European policies “but I suspect they will be similar”.

He added: “The Government plan assumes that herd immunity will eventually happen, and from my reading hopes that this occurs before the winter season when the disease might be expected to become more prevalent.

“However, I do worry that making plans that assume such a large proportion of the population will become infected (and hopefully recovered and immune) may not be the very best that we can do.

“Another strategy might be to try to contain longer and perhaps long enough for a therapy to emerge that might allow some kind of treatment.”