Test, test, test – that’s the key advice that the WHO is giving when it comes to curbing the COVID-19 pandemic. However, several countries – including The Netherlands and the United States – are still very reluctant to conduct testing. Why is this and what solutions are under development?
Testing in The Netherlands is predominantly carried out on Roche equipment. These are generic laboratory machines that are able to detect specific RNA and DNA structures in samples. The machines can be used for a wide range of purposes, from forensic research to medical applications. It is possible to determine whether someone is infected by taking mucus samples from people and checking whether the 2019-nCoV (novel corona virus) RNA is present.
Genetic code is now known
The equipment is already available in Dutch laboratories. This type of testing is now possible as the genetic code of the coronavirus is known. Testing does require other materials from Roche, the supplier of these machines. Except that availability of these materials is limited due to the enormous increase in demand. It is this factor in particular that is limiting testing capacity in The Netherlands.
This system also tests for the presence of the virus. Someone who was infected and has since recovered, no longer has the virus. Unfortunately, it is not possible to determine whether someone has been sick and is now resistant to corona using this method. This information is important in order to determine how far the epidemic has progressed. But also to find people who are now no longer a danger to vulnerable groups and are therefore able to be mobilized for certain care tasks.
New test methods
Nevertheless, as in any crisis, developments are fast-paced and new testing methods are rapidly emerging:
1. Chai Open qPCR
Originally started as a Kickstarter project, the Chai Open qPCR is an affordable DNA analysis device. ‘Affordable‘ means US$4,500 each. Its developers have now also devised a COVID-19 test system. However, this has not yet been certified for medical tests, although it can be used in research. For instance, it can verify if the virus is actually on door handles or other surfaces.
2. COVID-19 Ag Respi-Strip
Meanwhile in Belgium, Coris BioConcept has developed the COVID-19 Ag Respi-Strip. Similar to litmus paper, this is a strip which is inserted into a test tube. This test tube contains the test sample together with a buffer. The test produces results within 15 minutes. Which means the test is very fast. One disadvantage is that it is not extremely accurate. The test only gives a positive result in 70% of all infections. The manufacturer recommends the test as a quick step in the triage process. Nevertheless, it does not guarantee a conclusive result.
3. VivaDiag™ SARS-CoV-2 IgM/IgG Rapid Test
This test doesn’t test for the virus but for antibodies instead. This also makes the test suitable for research into who may have been infected. The test has only recently been approved as a matter of urgency by the American authorities. The test works with a few drops of blood and also resembles a pregnancy test – a plastic case with two openings. A few drops of blood and a smidgen of special fluid go into one opening. After a 15-minute wait, stripes appear in the other opening that indicate whether the test is positive or negative.