Herd immunity is possible – but can we achieve it? The Robert Koch Institute has examined how the coronavirus can be brought under control in Germany. Three points are therefore crucial.
The delta variant of the corona virus is also on the advance in Germany. It now accounts for almost half of all the findings examined in the laboratories, and the trend is rising. The mutant B.1.617 is considered to be significantly more contagious than the wild type of the coronavirus; the World Health Organization assumes that it will become the dominant variant worldwide.
This has consequences, also for the German vaccination campaign. On this Wednesday morning, according to figures from the Federal Ministry of Health, a good 47 million people in this country were vaccinated once, a good 32 million enjoy full protection – still too little to assume so-called herd immunity. She means the effect of vaccinations through which there is a lower risk of infection even for unvaccinated people. But how many people have to be vaccinated in order to be able to control the Covid-19 pandemic in Germany in this way and thus also to prevent heavy occupancy of the intensive care beds in autumn and winter?
Robert Koch Institute gives target vaccination rates
The Robert Koch Institute (RKI) has modeled a number of scenarios in order to find an answer to this question. It is a look into the future and a calculation with many unknowns: How high will the basic reproduction rate of the virus be? How many contacts will people have with each other? How long will the vaccination protection last? The Berlin disease fighters included these and other parameters in their calculations. An exact forecast is not possible, but a well-founded estimate is possible.
The result: At least 85 percent of the twelve to 59 year olds and 90 percent of the over 60 year olds in Germany must be vaccinated. “If this vaccination quota is reached in time, a pronounced fourth wave in the coming autumn / winter seems unlikely”, “provided that the population continues to adhere to the basic hygiene measures in addition to vaccination and, if the number of infections increases again, reduces contacts to a certain extent.”
85 or 90 percent vaccinated for herd immunity, which is significantly more than previously assumed. The RKI still considers it possible to achieve these necessary target vaccination rates, at least in theory. The summer should “be used urgently” for this. However, there are doubts that it will succeed. The immunologist Carsten Watzl recently showed himself in stern-Interview pessimistic about this. He assumes a necessary vaccination quota of 83 percent in the total population: “We would have to vaccinate almost 100 percent of the adult population to get this 83 percent. We will not achieve this value,” said the scientist. “Herd immunity can hardly be achieved with the Delta variant.” But: “Every vaccination counts.” With the vaccinations you can get through a fourth wave more easily and without lockdown.
Around 84 percent of people over 60 in Germany are currently vaccinated at least once. The determined willingness to vaccinate in this age group of almost 95 percent suggests that the goal of 90 percent can be achieved here.
There is still room for improvement with coronavirus vaccinations
In the younger age group, on the other hand, only 51.1 percent received at least one vaccine dose; almost 20 percent are fully vaccinated. Overall, the determined willingness to vaccinate is only around 84 percent, i.e. below the target rate. People between the ages of twelve and 18 were not interviewed. The RKI therefore continues to see a need for education, especially among young adults, in order to increase willingness to vaccinate. “Information and education on the safety and effectiveness of the vaccination are still relevant.”
In view of the increasing spread of the delta variant, the RKI is making three decisive recommendations:
- Motivate the still unvaccinated population to take advantage of the vaccination offer in summer in order to achieve the necessary vaccination rates as soon as possible.
- Provide sufficient capacity to administer the proposed quantities of vaccine.
- Continue to implement basic hygiene measures, including a slight reduction in contacts.
However: Even if the target vaccination rates in Germany should be reached before autumn – according to the RKI, the coronavirus cannot be eradicated by this alone. “For an elimination, it would also be necessary that the vaccination activities are also globally successful, so that viruses are not continuously imported and, depending on the vaccination rate, spreads again or lead to local outbreaks,” said the scientists. “Likewise, the development of a permanent animal reservoir would be an obstacle to elimination.” Whether all of these can be achieved or prevented is “doubtful”.
“The goal of achieving broad basic immunity in the population, through which the occurrence of severe illnesses is significantly reduced at the individual level and the virus circulation is significantly reduced at the population level, is realistic, however,” writes the RKI. In other words: herd immunity in Germany (and thus control over the virus) is feasible – despite the delta variant this year. The path leads through rapid vaccination, only through rapid vaccination.
