On this special coronavirus episode of The Nurse Keith Show nursing career podcast, Keith discusses insights gleaned from conversations with a top scientist regarding current COVID-19 research; the challenges of testing; and other topics salient to the ongoing pandemic that continues to disrupt lives and economies worldwide.
A great deal of effort is being undertaken by pharmaceutical companies, the biotech industry, and academic researchers to determine if previously approved drugs can be repurposed as anti-coronavirus treatments for the current pandemic. Thousands of drugs are being tested for efficacy, an example of which is hydroxychloroquine, a drug previously approved for the treatment of malaria. Hydroxychloroquine appears to have some activity against CoV2, but we don’t yet know how well it can actually work.
A few highlights:
- Previously approved drugs are first placed in human cell cultures to see if they inhibit the ability of CoV2 to bind to human cells or create more copies of themselves
- If any promise is shown, the research then moves to animal models (ferrets are being used because the SAR-CoV2 virus replicates well in ferrets (and cats)
- If they do well in animals, the next step is testing for efficacy and safety in humans
- Some drugs are chosen because they’re known antivirals, such as the influenza drug, favipiravir
- Some drugs are chosen because they have a molecular similarity to chloroquine or chloroquine-like compound
- Other drugs are identified since they work in the host human cell and prevent the host from destroying itself
- Preventing an inflammatory cytokine storm is also a path of current research
- An NIH article on cytokine storm
- Molecular modeling (e.g. digital simulation of drugs binding to proteins) are another path of inquiry
- The “holy grail” would be identifying an anti-coronavirus drug that can prevent viral infection regardless of the strain of the coronavirus (e.g. SARS-CoV1, SARS-COV2, MERS-COV) or even in the presence of spontaneous mutation
- The virus that causes COVID19 is a coronavirus, and belongs to a subset of coronaviruses that cause sudden acute respiratory syndrome (SARS), a dangerous respiratory condition that can lead to dramatic and sudden pulmonary failure
- Official names have been announced for the virus responsible for COVID-19 (previously known as “2019 novel coronavirus”) and the disease it causes. The official name for the disease is coronavirus disease or COVID-19; the virus itself is called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)
- There is active vaccine development going on against CoV2 and there are several vaccines in clinical trials; we should not expect a vaccine any time soon as a successful vaccine may not be able to be tested, approved, and then manufactured in massive numbers for at least 18 months
- We need to know who has the virus, whether symptomatic or not. The only way we can isolate the virus is to know who has it and then isolate them and do contact tracing. This would result in what may be called precision social distancing. If people are walking around unwittingly spreading the virus, everyone has to social distance. I and many others have been saying for many weeks that we need to not just test those who have bad symptoms – we need to test everyone but here in 21st-century America. But we started with tests from the CDC that were faulty after the US rejected the German tests offered by the WHO and we’ve been behind ever since.
- Can we trust positive tests? While a false positive can lead to quarantine of one individual who is perhaps actually negative, it’s a better scenario than having to quarantine everyone because we don’t know who’s a carrier or not.
- False negatives are more problematic and dangerous, and the % of false positives is said to be fairly high.
- In a New York Times op-ed, Harlan M. Krumholz, director of the Yale-New Haven Hospital Center for Outcomes Research and Evaluation, wrote, “Some of my colleagues, experts in laboratory medicine, express concerns the false-negative rate in this country could be even higher.”
- Patients have received suspicious results suggesting they don’t have the coronavirus infection despite having symptoms that are consistent with what we know about the virus, including high temperatures and a cough.
- The most notable example of a false negative is Li Wenliang, an ophthalmologist in Wuhan, China, who brought COVID-19 to international attention. Li died of the virus, but only after he repeatedly tested negative for the disease. No test is perfect. The latest rapid influenza test, for example, has a false-negative rate of around 20 percent.
Sensitivity measures how often a test correctly generates a positive result for people who have the condition that’s being tested for (also known as the “true positive” rate). A test that’s highly sensitive will flag almost everyone who has the disease and not generate many false-negative results. (Example: a test with 90% sensitivity will correctly return a positive result for 90% of people who have the disease, but will return a negative result — a false-negative — for 10% of the people who have the disease and should have tested positive.)
Specificity measures a test’s ability to correctly generate a negative result for people who don’t have the condition that’s being tested for (also known as the “true negative” rate). A high-specificity test will correctly rule out almost everyone who doesn’t have the disease and won’t generate many false-positive results. (Example: a test with 90% specificity will correctly return a negative result for 90% of people who don’t have the disease, but will return a positive result — a false-positive — for 10% of the people who don’t have the disease and should have tested negative.)
Serologic tests look for antibodies, proteins in your blood that show us that you’ve had the virus at some point in the past and may still have it or not. This can also have false +’s and –‘s.
DISCLAIMER: In these episodes regarding COVID-19, I reference the most up-to-date information I can, as well as adding personal opinions and reflections from me and my guests. Please note that the situation is changing by the moment, and any information shared in the course of any episode may not apply once new data or evidence emerges. Please also note that nothing shared in the course of any Nurse Keith Coaching COVID-19 podcast is intended for diagnosis or treatment; please consult your healthcare provider, your local Department of Health, the CDC, the WHO, or other reputable evidence-based sources.
If you hear or read something I have shared that appears to be erroneous, if you can, please send an email me directly at firstname.lastname@example.org. Thank you for understanding, stay safe, and keep informed.