The U.S. went from having no tests available for Covid-19 diagnostic to develop mutliple different tests within a few weeks. These tests have been important to globally fight the pandemic. With the current spread of the virus, we all hope that a Covid-19 test will be as simple to perform as a pregnancy test.
Since the beginning of January, the FDA – the U.S. Food and Drug Administration – has worked with more than 230 test developers who have or are expected to submit requests for FDA emergency authorization of their tests; to date, 20 authorizations have been granted. In addition, more than 110 laboratories have notified the FDA that they have begun using their own tests. Having this number of tests available in such a short time period is impressive. However, for several weeks public and private labs have raced to boost their testing capacity, but media reports from several areas across the country that it is still difficult to get tested.
Opening up America
President Trump has unveiled guidelines for opening up America Again, a three-phased approach based on the advice of public health experts. These steps will help state and local officials when reopening their economies, getting people back to work, and continuing to protect American lives. One of the most crucial part is then how to scale testing and contact tracing.
So many different tests
The U.S. works with increasing the number of available tests as well as the pace in which these tests are distributed. The U.S. Centers for Disease Control and Prevention (CDC) have had great difficulties when they, in a joint effort with FDA, are trying to get test kits out. The number of tests increase but has not reached the same level as, for example, in China or South Korea at the same time after their first confirmed case.
The current coronavirus testing has so far had mixed success around the world. The Certified Public Health Laboratories have played an important role in the U.S. fight against Covid-19. Until March 13th, these laboratories were the only ones except the CDC’s own facilities that had permission to perform tests. Despite early challenges, Public Health Laboratories in all 50 states as well as District of Columbia, Puerto Rico and Guam are now able to test for Covid-19. Overall, there are 97 approved laboratories all over the U.S. The number of performed tests is increasing as more laboratories are getting certified to do them.
CDC has also developed a new laboratory test kit for use when testing patient specimens. The test kit is called ”Centers for Disease Control and Prevention 2019-Novel Coronavirus (2019-nCoV) Real-Time Reverse Transcriptase (RT) – PCR Diagnostic Panel”. The test is intended for use with upper and lower respiratory specimens. It is intended for use by qualified laboratories that are certified under the Clinical Laboratory Improvement Amendments (CLIA) to perform high complexity tests.
March 21st FDA issued the first permission for a new Covid-19-diagnostic, the Cepheid Xpert Xpress SARS-CoV-2-test. The result is done within a few hours, instead of the several days that the present tests can take. The test performs PCR (Polymerase Chain Reaction) in real-time to extract RNA from the sample and by that detect SARS-CoV-2 with a high sensitivity.
Abbot is the company that was the most recent to get approved by the FDA to perform fast tests (27th of March), something they do with an adaptation of their analysis system ID Now. The unit should be able to leave a positive response within five minutes, and a negative result within 13. The company is expecting to be able to perform 50.000 tests daily.
On April 1, the FDA issued the first approval of a test to measure antibodies in the blood that detect if a person has been exposed to Covid-19. This type of anti-body test does not diagnose if a person has an ongoing infection. However, the method aims at identifying proteins (anti-bodies) in the blood. The presence of these proteins indicates that you’ve been exposed to the virus and probably have some sort of immunity. It is still uncertain how strong this immunity is and how long it will last. CDC is also working towards the development of a new laboratory test through serological diagnostics.
The prediction is that, within a few weeks, several anti-body tests will be available on the market. The FDA has adopted a new policy that makes it possible for companies to sell tests if the FDA has information about the product. The FDA has currently knowledge about 70 companies that will produce test kits. Since these test kits will not be formally tested by the FDA, many are sceptical about the quality.
Several companies have also developed products for home testing, but none has yet been approved by the FDA.
The test has to be reliable and affordable
It seems as if the rapid tests are the easiest to use and administer, but they are by far the most unreliable. The World Health Organization recommends against their use and warns about their quality.
Another important question is the affordability of the tests performed in the U.S. A potential hurdle to ensuring scaled testing is the cost of a diagnosis for individuals. If the cost is high, people may not come in to tests themselves.
In addition, some countries are considering issuing ‘immunity ceritificates’. If individuals test positive to the antibodies to the virus, it would allow them to leave their homes and lockdowns earlier that the rest of the population – known as the so-called heard immunity. The rapid test would be important for people working in the health care system or elderly homes etc, and would allow them to be exempted from restrictions at their work.
Finally, the new Covid-19 testing methods spark caution and optimism for the different states in the U.S. as well as other countries, to slowly open up.
Earlier blog posts on Covid-19 from the OSI-office in Washington DC:
A link to all the blog posts related to Covid-19 from the OSI-offices in Brazil, China, India, Japan, Republic of Korea and the U.S.
Henric Johnson & Nora Myrne Widfors