Professor Shingo Iwami of Nagoya University Graduate School has developed simulation software to verify the timing of the end of quarantine for people infected with the new coronavirus through antigen tests in joint research with assistant professor Keisuke Ejima of Indiana University in the United States.This allows for a flexible and safe isolation strategy that allows early termination of isolation after a predetermined number of negative antigen tests.
People infected with the new coronavirus are quarantined for a certain period of time (5 to 10 days) after being confirmed positive, but depending on the person, they may have lost their infectivity before the end of the quarantine, or they may retain it even after the end of the quarantine.If the loss of infectivity can be confirmed by antigen testing, it will be possible to individually set the isolation period for infected people, and to reduce the risk of infection and return to society early.However, the required number of negative confirmations and test intervals have not been verified so far.
In the study, computer simulations were conducted to determine the probability (risk) of an infected person who retains infectivity at the end of isolation and the loss of infectivity when antigen tests are performed under various conditions (test interval and number of negative confirmations). We calculated the period of isolation (burden).As a result, it was found that the burden can be reduced while suppressing the risk by well designing the conditions for ending the isolation.In addition, if the detection limit value of the antigen test exceeds the infectious limit value (the amount of virus that an infected person is considered to be infectious), it is necessary to confirm negatives many times. I know it can be shortened.
Currently, different countries adopt different isolation standards based on clinical and epidemiological data and empirical rules. It is said that it can contribute to the establishment of flexible isolation guidelines.
Paper information:[Nature Communications] Designing isolation guidelines for COVID-19 patients with rapid antigen tests