Should Germany be testing more vaccinated people in the Covid fourth wave?
Germany's Covid testing strategy is aimed at unvaccinated people. But there are calls for everyone - regardless of vaccination status - to get tested regularly as the fourth wave takes hold.
A research group based in Berlin has called for a far-reaching testing strategy that also targets vaccinated and Covid-recovered people - as well as tougher restrictions - in view of the accelerated pace of infections and rising hospital admissions.
"An effective testing strategy for autumn 2021 must include the vaccinated/people who have recovered (from Covid) because, even if they rarely show severe courses (of the illness), they are nevertheless involved in the transmission of the virus," the group's new report to the German Federal Ministry of Education and Research states.
The scientific team, led by mobility researcher Kai Nagel from the Technical University (TU) Berlin, includes mathematician Christof Schütte and computer scientist Tim Conrad from the Zuse Institute Berlin (ZIB), reported regional newspaper the Tagesspiegel on Monday.
Based on earlier modelling predicting a fourth wave for autumn and rapidly increasing hospital numbers, the group simulated various test strategies. The aim was to identify measures that could significantly slow down infection dynamics and avert a "critical situation" where hospitals become overloaded.
In the report, the group acknowledges that predictions from the previous model happened earlier than expected because of the more transmissible Delta variant. Due in part to people travelling in and out from abroad, the mutation became dominant in Germany by the end of June, the group said - adding that "exponential growth" clearly started early.
At the beginning of September, the total number of Covid infections in Germany since the pandemic started rose above the four million mark.
On Monday Germany recorded 4,749 new infections within 24 hours and eight deaths. The 7-day incidence rose to 84.3 infections per 100,000 people. A week ago the incidence stood at 75.8.
Which measures are researchers calling for?
Overall, the group names three measures that they believe could help in the pandemic fight.
They say masks should remain mandatory on public transport and in shops - a rule already in force.
Secondly, the group calls for the '2G rule' indoors where there are lots of people. This means that vaccinated (geimpft) and people who've recovered from Covid (genesen) would only be allowed into many public indoor spaces - not unvaccinated people who've been tested for Covid (getestet).
Thirdly, they call for regular Covid testing for all - including the vaccinated and those who've recovered. PCR lab tests are preferred - but rapid antigen tests could also be used.
Tell me more about this testing idea...
The third point is the core element of the study. The modellers explain that an effective testing strategy would target the 2G group "because the vaccinated/recovered are also involved in the transmission of the virus".
They say that this can push up the number of infections overall and lead to higher hospital admissions usually in the non-vaccinated group.
This scenario assumes "that under certain adverse circumstances, hospital crowding will again occur despite vaccinations". The researchers acknowledge, however, that this is speculative. To prevent this kind of situation at an early stage, they recommend "consistently monitoring hospital incidence in particular, as well as their occupancy rates, and - if necessary - taking prompt action".
According to the latest RKI data released on Friday, the number of Covid patients admitted to hospitals per 100,000 people within seven days stands at 1.83 (previous day: 1.74) in Germany. Around three weeks ago, the incidence was about 1.19.
A nationwide threshold for when the situation should be considered critical is not provided for hospitalisation incidence, in part because of large regional differences.
The research group also slammed the government's decision to get rid of free antigen tests from October 11th.
Instead, the experts advocate maintaining the current testing strategy and encouraging vaccinated and recovered individuals to test before high-density indoor activities. Finally, they would "optimally even like to see the more accurate PCR tests added to the catalogue of those tests that can be used free of charge".
Currently PCR tests are only free of charge to people with Covid symptoms.