In view of the increasing number of Covid 19 cases, 80 international experts have published an open letter. In it, they describe which measures are suitable from a scientific point of view to contain the pandemic and to protect human life and the economy. They strongly warn against herd immunity approaches that rely on allowing large sections of the population to become infected and hoping that natural immunity will end the pandemic.
The Sars-CoV-2 coronavirus is highly infectious and since it is a new virus against which there is not yet sufficient basic immunity, it is spreading rapidly. To curb the transmission, many countries have adopted far-reaching restrictions on public and private life. Some see so-called herd immunity approaches as an alternative to such measures. The idea behind it: If the virus spreads across large parts of the population and only risk groups are protected from infection, many people would become immune to the virus within a short period of time. The herd immunity prevents the virus from spreading further, which would also protect non-immune risk groups, proponents argue.
Warning of uncontrolled spread
“This is a dangerous fallacy that is not supported by the scientific evidence,” warn 80 international experts in an open letter that they published in the specialist magazine The Lancet and on a website specially set up for this purpose. The authors have expertise in areas such as epidemiology, virology, infection medicine, psychology, sociology, health policy and mathematical modeling. They refer to their statement as the John Snow Memorandum, in honor of the British medical doctor John Snow (1813-1858), a pioneer in epidemiology. The authors acknowledge that the ongoing restrictions have understandably led to widespread demoralization and declining public confidence, and therefore increasing interest in herd immunity approaches.
“An uncontrolled spread of the virus among young people, however, carries the risk of a significantly increased disease burden and mortality in the entire population,” warn the scientists. Evidence from various countries shows that it is practically impossible to limit uncontrolled outbreaks to certain population groups. Apart from that, it is highly unethical to isolate the risk groups and thus large parts of society – the authors assume around one in three – over a long period of time. Existing inequalities would be exacerbated even more than the pandemic is already the case. In addition, the health systems would be overloaded, which would both be at the expense of the employees and would jeopardize the acute and routine care of other sick people.
Repeated outbreaks possible due to decreased immunity
In addition, it has not yet been clarified how effective and how long a recovered Covid 19 disease protects against a new infection. If the immunity decreases again over time, new outbreaks can occur over and over again for years. The pandemic would not be over and risk groups in particular would be exposed to considerable danger for an indefinite period of time. “Special efforts to protect the most vulnerable are important, but they have to go hand in hand with strategies that start at the population level,” the researchers say.
They counter the argument that lockdown measures would damage the economy by stating that the economy would be all the more affected if a large number of workers suddenly fell ill and there was no planning security. From an economic point of view, a herd immunity approach would therefore only be a sham solution. “Protecting our economies is inextricably linked to controlling Covid-19. We have to protect our workforce and avoid long-term uncertainties, ”the publication said.
Return to an “almost normal life”
It is crucial to act decisively and quickly. “Effective measures that suppress and control transmission need to be fully implemented and backed by financial and social programs that stimulate societal responses and address the inequalities exacerbated by the pandemic,” said the researchers. In order to lower the transfer rates and prevent future lockdowns, they believe that short-term restrictions will be necessary. Comprehensive testing and tracking systems are designed to enable rapid responses to local outbreaks. If this succeeds, life could go on almost normally without the need for general restrictions. Countries like New Zealand, Japan and Vietnam have shown how this is possible.
In conclusion, the researchers conclude: “The evidence is very clear: Keeping the spread of Covid-19 under control is the best way to protect our societies and economies until safe and effective vaccines and therapeutics are available in the months ahead . We cannot afford distractions that undermine an effective response; it is important that we act as quickly as possible based on the evidence. “
Source: John Snow Memorandum, The Lancet, doi: 10.1016 / S0140-6736 (20) 32153-X