Ebola: detection strips instead of lab tests

Interview with Dr. Peter Miethe, CEO, fzmb GmbH, Research Center of Medical Technology and Biotechnology



Photo: Blood vial with the label "Ebola test"

Blood tests, that look for example for the Ebola virus, are often expensive and can only be conducted by trained staff; ©panthermedia.net/ federicofoto

In this interview with MEDICA-tradefair.com, Dr. Peter Miethe talks about a test strip that detects the presence of the Ebola virus, the trial phase in Guinea and the requirements for point-of-care diagnostics for use in remote settings.

Dr. Miethe, last year the fzmb has developed a point-of-care test to detect the Ebola virus. What is the background for this?

Dr. Peter Miethe: Against the backdrop of the Ebola outbreak last year, we made and validated a marketable lateral flow test together with the Senova Company from Weimar. This is a rapid Ebola virus VP40 antigen test. The antigen is expressed in the viral capsid.

We have had a very long lead time on this subject. I have personally been focusing on this since 1999 and the fzmb since 2007. The development was completed in 2011.

Do you need special equipment for this test?

Miethe: No, it works like a pregnancy test. You place a blood or saliva sample into a cartridge. This sample passes through a porous membrane. A sample that tests positive subsequently shows a bar in the results window and no bar if it tests negative. It also displays a control line that shows whether the test was performed correctly. A test kit for approximately 76 Euros lets you conduct 20 tests.

You have tried the test last year during the Ebola outbreak in Guinea. What was the work like there?

Miethe: We worked closely with the Donka Hospital in Conakry to validate the test. We assembled a serum panel with the laboratory there. The panel consisted of approximately one hundred positive and several hundred negative samples. We conducted nucleic acid detection for the Ebola virus using the PCR method (polymerase chain reaction) as a reference.
Photo: Patient's hand with a single blood drop

Test strips can be an alternative to expensive, elaborate lab analysis. They often only require a small amount of blood and no further equipment. Thus, they are ideally suited for use in remote areas; ©panthermedia.net/ vverve

How reliable has the VP40 antigen test turned out to be?

Miethe: VP40 shows up later than nucleic acid in the patient’s blood and also does not exhibit an increased sensitivity. Simply put: you can conduct nucleic acid testing two to four days after infection and conduct the VP40 antigen test another two to four days after that. However, both have different applications.

The nucleic acid test is relatively expensive and can only be conducted in the lab. It costs about twenty times as much and can only be performed by trained staff. There are also efforts to implement this in a test cartridge, but the nucleic acid test is complex and expensive.

The rapid test is actually meant for testing out in the field. It can be easily transported and brought to remote areas. It is almost ideal for this. It is not necessarily the best means to detect an infection early, but it can be used to detect the Ebola virus in dead persons.

What requirements do point-of-care tests generally need to meet for use in the field?

Miethe: Ideally, they should be as specific and sensitive as a laboratory test while they should be produced at low cost and stored indefinitely at room temperature at the same time.

However, tradeoffs often need to be made to meet these requirements. The VP40 antigen test can definitely be produced at low cost, is easy to transport and store. In turn, it is not as accurate and sensitive as a laboratory test.

In your personal assessment, has the previous outbreak changed attitudes about Ebola in the diagnostics sector? Is it taking this disease seriously?

Miethe: No, I do not think so. However, this is also because Ebola can be managed well with good hygiene habits. The fact that things have gotten this far also had to do with the basic conditions in the respective countries.

What other development are you planning in terms of the Ebola tests?

Miethe: Our general goal is to develop decentralized diagnostic systems. We have now started a new project based on the experiences in Guinea: we want to create small, mobile analytic systems that are more specific and sensitive than a simple test strip but not necessarily much more expensive. The idea here is to print them in 3D so they can also be built and repaired on site.
Photo: Timo Roth; Copyright: B. Frommann

© B. Frommann
