Strict lockdown measures must continue to stem the rise of more dangerous COVID-19 variants

While COVID-19 vaccine deployment is now underway, a threat to vaccine effectiveness comes from the emergence of new strains, both existing - such as the UK, South Africa and Brazil variants - and those yet to come. 

In an editorial for the journal Virulence, Professors Neil Hall, Cock van Oosterhout, Hinh Ly, and its editor-in-chief Prof Kevin Tyler, say: “continuing public health efforts to encourage vaccination as well as continued use of proper personal protective equipment (PPE), such as proper masking and maintaining safe social interactions, is of utmost importance. 

“Humanity is faced with a new reality. The faster we adapt, the better our long-term prospects. We must stop the evolution and spread of more virulent virus strains now. We, therefore, support public health policies with strict control measures in order to protect our public health system, our individual wellbeing, and our future.” 

The researchers look back at what has happened and how best to respond now, highlighting that the roll-out of economic stimulus packages and easing of restrictions in many countries appears to have fuelled the rate of person-to-person transmission.

As a result, they say at the start of winter the population number of the virus continued from a much higher base than would otherwise have been the case, adding: “By not absolutely minimising the ‘R number’ when we had the chance, we extended the pathogen transmission chains, providing more opportunity for it to mutate and evolve into more virulent variants.”

Additionally, the authors highlight that an increased virulence - or higher R value - can also result from the virus evolving the ability to infect people for longer. They go on to warn that continued virus evolution in animal hosts, such as cats and mink, followed by transmission into susceptible human hosts, poses a significant long-term risk to public health; suggesting that the vaccination of certain domesticated animals might be important to halt further virus evolution and ‘spillback’ events.

Pictured above: Prof. Neil Hall, Director of the Earlham Institute (EI) in Norwich. 

“To give vaccines the best chance of controlling the virus we need to prioritise reducing cases through more rigorous transmission control,” comments Director of the Earlham Institute (EI) Prof Neil Hall. “Otherwise, we’re at risk of virus variants appearing that escape the vaccine-induced immunity, and this pandemic will linger on for years.

 “A major issue is our current high transmission rate; although the coronavirus has a low mutation rate, every transmission of this virus creates an opportunity for adaptation. Therefore, there is always a chance of new variants of the virus emerging that are vaccine-resistant. 

“These potential variants could also be transmissible in domestic animals, which is why my colleagues and I make a case for the continued use of strict control measures to give the vaccine the best chance of long-term efficacy, as well as considering a programme of vaccination for pets in the future.”

The editorial goes on to say: “Vaccination against a viral pathogen with such high prevalence globally is without precedent and we, therefore, have found ourselves in uncharted waters. However, what we can be certain about is that, as long as the vaccine stays effective, a higher uptake of the vaccines will reduce the number of COVID-19-related deaths, stem the spread of the transmissible strain of the virus, and reduce risk of the evolution of other, even more, virulent strains. 

“Furthermore, it is not unthinkable that vaccination of some domesticated animal species might also be necessary to curb the spread of the infection.”

The editorial is freely available online: ‘COVID-19 evolution during the pandemic – Implications of new SARS-CoV-2 variants on disease control and public health policies’, authored by Cock van Oosterhout, Neil Hall, Hinh Ly, and Kevin M Tyler, and published in Virulence on 25 January , 2021.