This is the best way to prevent the introduction and spread of the coronavirus.
A close-knit test program using RT-LAMP or PCR tests would be the best way to prevent the introduction and spread of the SARS-CoV-2 virus in old people’s and nursing homes. According to a study by several Viennese research institutions and Caritas of the Archdiocese of Vienna, the fast and yet very precise LAMP method in particular has great potential. If you test the staff with it twice a week, it prevents the spread very effectively.
The spread of Covid 19 infections in retirement and care facilities has proven to be a major problem in the course of the corona pandemic. In nearly all countries with major outbreaks in this area, the death toll went up. After this scenario fortunately did not occur in Austria in the spring, it has become apparent in the past few days that the second corona wave is developing significantly more force in Austrian nursing and old people’s homes.
Sound test strategy
Now it is high time to find, with “not populist, but scientifically sound, good test strategies, how we can find the balance between freedom, quality of life and good protection together,” said the medical director of Caritas ED Vienna, Thomas Wochele-Thoma, in conversation with the APA. Since nursing homes are lived in and cannot be closed like schools or other facilities to break chains of infection, this is doubly important. “The residents deserve to get the best possible strategies” and to do so as quickly as possible, “because the number of infections will not go down so easily,” said Wochele-Thoma.
“If the virus is inside a facility, it spreads very quickly,” including the worse disease progression, which unfortunately is often threatened in old age. That was shown by the first wave of illness. For this reason, the Caritas and scientists from the Complexity Science Hub (CSH) Vienna, the Medical University of Vienna and other research institutions started a detailed analysis of the processes and infection chains in the houses in the summer. “We tried to understand what the moments are when it spreads,” said Wochele-Thoma.
Then researchers around Jana Lasser and Peter Klimek from the CSH and the Meduni developed an agent-based simulation model in which virtual residents and employees in the nursing homes move realistically. In addition, there was the expertise of scientists around Johannes Zuber from the Research Institute for Molecular Pathology (IMP) and the “Vienna COVID-19 Diagnostics Initiative” (VCDI) on test methods such as PCR tests, rapid antigen tests or the new RT developed by Viennese researchers -LAMP method, and their respective advantages and disadvantages.
According to Klimek, the latter approach proved to be particularly effective in the “very precise simulation”, in which the genetic make-up of the virus is detected more easily and more quickly than with the very precise PCR test. The unrivaled accuracy of the PCR test is offset by the fact that it takes three to four hours to get the result – not counting the logistics from sampling to feedback. The antigen tests in turn produce results in around 15 minutes, but are usually only really accurate when a person is already relatively infected with the virus.
“The study showed that the most important thing is the time from the test to the receipt of the result and the frequency of the tests,” Klimek told the APA. The second question was who should be tested best. Since the virus often gets into the houses through the staff, “we have shown that it is not absolutely necessary to test residents and staff”. If only employees undergo a LAMP test twice a week, which, in contrast to many antigen tests, usually also reliably detects asymptomatic virus carriers, one has “less than one subsequent case” with an infected person in the staff, the scientist explained. Even if it is possible to provide feedback within a day for PCR tests, the effect is like that. If you find someone infected with such a highly sensitive procedure, then all residents in their area of use must be tested. In this way, possible chains of infection are quickly identified and interrupted.
In the case of antigen tests, Klimek and Wochele-Thoma emphasized due to the limitations in accuracy that a negative rapid test result is a snapshot. These tests offer a certain insight into what is happening, but you shouldn’t lull yourself into a false sense of security and perhaps let other preventive measures – wearing a mask, ventilating and keeping conversations short – dragged. The LAMP method also offers the advantage that gargle solutions can be analyzed, which saves the elderly residents from having to take unpleasant samples.
In eight Caritas ED Vienna houses, the findings from the study are implemented with PCR tests, which are quickly analyzed in the VCDI’s test infrastructure, said Wochele-Thoma. 25 employees in the early stages of infection have already been identified. “The first experiences are promising and we know that we were able to end the chain of infection relatively early.” One company is already gaining experience with the new, faster LAMP test.