COVID-19 TEST PROCEDURENew Coronavirus Gargling Test Introduced at the University

Press Release No. 14/2021
17 February 2021

Heidelberg researchers develop test procedure that is being used for on-campus examinations and classes

For approved on-campus events such as laboratory practicals or on-campus examinations which are strictly necessary for continuing or completing a degree course, Heidelberg University is offering an additional measure besides the required hygiene routines and mandatory distancing arrangements. In the context of a study, a corona gargling test is available, which was developed at the Center for Molecular Biology of Heidelberg University (ZMBH). It supports measures to prevent the virus and possible mutations from spreading, by detecting asymptomatic carriers of the virus as well as those who have not yet developed symptoms. The aim is to interrupt possible infection chains at an early stage. Teachers can order test kits for the students. The intention is for university staff, too, to be offered the opportunity of a test.

Prof. Dr Michael Knop and Dr Simon Anders led the development of the test procedure at the ZMBH in cooperation with the junior research group of Dr Viet Loan Dao Thi and the Center for Integrative Infectious Disease Research (CIID) of the University Hospital Heidelberg. It is based on a saline gargle sample and detection of viral SARS-CoV-2 RNA by means of an isothermal enzymatic reaction. The samples can be analysed within approximately eight hours with the aid of a robotic platform in the experimental test station that the Center for Molecular Biology of Heidelberg University has set up with the virology division. The test procedure has been approved for research purposes but has not been certified yet and is therefore not available commercially.

With the test, individuals can be identified as early as two or three days after they have been infected. Furthermore, the virus can be detected for some time after the infection, making this an efficient way of uncovering infection chains. The test was developed in spring 2020, during the first wave of the pandemic, and presented in peer-reviewed journals. “In summer we again considerably improved our test procedure,” says Prof. Knop. According to the scientist, the sensitivity of the Heidelberg test procedure is now significantly higher than that of commercial antigen rapid tests.

An appropriate number of test kits will be made available to those taking part in approved on-campus examinations or classes. As an additional measure besides hygiene rules and distancing arrangements on site the corona gargling test is primarily intended to minimise the risk of spreading the virus that may arise through increased mobility – e.g. when students travel to Heidelberg in the examination phase. The university is covering the costs for the tests from internal funds.

Participation in the test is voluntary. Those who want to be tested must register their kit online using the enclosed access code. Their contact details will be encrypted so that the test is carried out pseudonymously. The gargle sample can be taken at home. The samples are collected and taken to the test station for evaluation. The results will be available that very evening or the next day. The test persons can then access their result online with the aid of their code.

Positive test results will be validated using a diagnostic PCR test and, as required by law, the health authority of the Rhine-Neckar District will be informed so that it can take up contact tracing. Positively tested individuals may approach the university’s central team for COVID-19 reporting by mail. There they will receive confidential advice and support. “Even though to date our test laboratory has only been approved for research purposes we can make an important contribution to reducing the risk of infection with our rapid test procedure. Our study will show how well such voluntary tests are received,” says Prof. Knop.

As far as the test station capacities allow, the test procedure can also be made available to staff at the university.


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