Controlling the pandemic without vaccines: the Covid-0 strategy

Logistical problems in the distribution of vaccines have shown that the control of such a complex pandemic cannot be relied on vaccine prophylaxis alone. What is the best way to manage the crisis, then? Several voices in the scientific community have long advocated a strategy of control and maximum suppression of transmission known as Covid-0. Unlike the strategy of achieving herd immunity through progressive infection, or the strategy of containment or mitigation to avoid health collapse (the famous flattening of the curve followed in much of the Western world), the Covid-0 approach aims to keep infections at the lowest levels and even reduce them to zero in some specific areas.

Written like this, and given the experience of our environment, this strategy seems too good to be true. But it is. Countries like South Korea, Taiwan, Singapore, Vietnam and New Zealand have demonstrated it. It can even be achieved in places where there has been high community transmission, such as in the Chinese city of Wuhan or the Australian state of Victoria. Some of the keys to success are the increased ability to detect and trace the chains of transmission of the virus and the management of outbreaks through economic and welfare support to ensure the isolation of cases and contacts. As published in a review article in the British Medical Journal by public health professor Michael Baker, from the University of Otago in New Zealand, and other researchers, this strategy reduces the number of deaths and people with sequelae, as well as mitigating the consequences of the lack of social equity that the pandemic has revealed in many countries. On the other hand, the economic effects of the preventive actions involved, such as localized and short-term lockdowns at the beginning of outbreaks, are offset in the medium term because if the circulation of the virus is reduced significantly, the economy can recover more easily than with other strategies. According to the authors, the fact that countries that have implemented it have suffered fewer deaths and less economic recession supports this approach.

A possible strategy?

In a more informative text, the same author argues in the newspaper The Guardian that the strategy works with more infectious variants of the virus and, at the same time, helps to ensure that not so many new variants appear.

In an article on this same approach published by the Institute of Global Health in Barcelona, it is argued that "preventive and early action to maintain control of transmission not only avoids the collapse of health care at all levels, also by pathologies that are not covid-19, but also allows to preserve the physical and emotional health of citizens and health professionals, in addition to maintaining social and economic life".

According to the first author of the article, Anna Llupià, of the preventive medicine and epidemiology service of the Hospital Clínic in Barcelona, "the Covid-0 strategy is the one that most cares for both the life and the way of life of people". One of the problems with the current approach to mitigation is that "measures to avoid the health emergency are not only a solution, but create other problems in the economic and social sphere". Therefore, "we should try to keep them short and use them sparingly", Llupià concludes.

Now, would it be possible to apply the Covid-0 strategy to the Catalan or Spanish sphere? "Now we are in a situation of minimizing damage", says Professor of Pharmacoepidemiology at the University of Oxford Daniel Prieto-Alhambra, "but we could have done it last summer". "With the data we have today, this strategy is the best", he adds. According to the researcher, "we have to look beyond the short term and talk more about this approach". According to him, "after the current restrictions and with the effect of the vaccines, there will be another opportunity to do it next summer". "We have to prepare public opinion for it", he remarks.