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October 9th, 2020


This week brings a closer look at Abbott testing and the experience at the White House, in addition to our updates on the CDC, FDA, and the latest in scientific research on COVID-19. As always, if you were forwarded this newsletter or you are viewing it online, you may join the subscriber list for free by completing the form here.

1) Airborne Transmission and the CDC

On OCT 5th, the CDC updated its webpage “How COVID-19 Spreads” to include airborne transmission. This classification is simply an acknowledgement by the CDC that there have been cases where the infection seems to have spread by “small droplets and particles that can linger in the air for minutes to hours” and infect people who are “further than 6 feet away from the person who is infected or after that person has left the space.” They also note “available data indicate that it is much more common for the virus that causes COVID-19 to spread through close contact with a person who has COVID-19 than through airborne transmission.” Though the CDC just published this information this week, the World Health Organization published it sometime ago after pressure from the scientific community to acknowledge the existence of airborne transmission of COVID-19. It is important to know that our recommendations have assumed this transmission for sometime, and have not changed. Vigilant use of masks, distancing, and ventilation remains critical in fighting the spread.

2) FDA Vaccine Requirements

This week the FDA released revised guidelines for Emergency Use Authorization for Vaccines to Prevent COVID-19. The document details the submission requirements for manufacturers submitting an application for emergency authorization of a vaccine. The key updates include the requirements around safety which now include: a minimum of two months of follow up after the last dose of vaccine is given to a volunteer for side effect surveillance, and subjects “numbering well over 3,000 vaccine recipients” in order to allow for sufficient side effect detection. The requirement for two months of surveillance is likely to delay the application for vaccination for several manufacturers according to this review. The FDA has also asked manufacturers to consider delaying their application until they have sufficient doses manufactured to begin administration on a large scale.

3) Abbott Rapid Tests

Abbott has manufactured several tests for COVID-19 that have received emergency authorization. Two specific tests have received a lot of media attention recently, the Abbott ID Now and the Abbott Binax Now. Both of these are “rapid” tests that return a result within 15 minutes and are made to be administered at the point of testing, immediately after obtaining a swab from a patient. The Abbott ID Now is a “molecular” test, which detects the RNA presence of the virus. These tests have been the standard relied upon for most of the pandemic, and typically take hours to days to deliver a result. The ability to perform one in minutes was a tremendous breakthrough. Though the initial testing from Abbott showed great promise, multiple follow up studies (see list below) have shown that it can miss up to 25% of positive cases or more, and deliver a small number of false positives, making it far less reliable than its counterparts with longer turnaround times.

The Abbott Binax Now test is an “antigen” test, detecting a protein from the virus instead of DNA. This is the same technology that delivers rapid strep and flu tests at most clinics, and one that Abbott has used in the past for the RSV and Malaria testing. Though these tests return results in about 15 minutes, they are known to be much less sensitive, meaning they miss positive results. Studies of the non-COVID Binax versions have shown variable rates of accuracy with the testing missing 15-80% of cases. Results from Abbott testing of the COVID-19 version show promise quoting accuracy of 97% or more (based on approximately 100 samples), but real world data is still pending.

So, if these tests are not as accurate, why use them? In August, the U.S. Department of Health and Human Services awarded a $760 million contract to Abbott to deliver 150 million rapid Abbott Binax Now COVID-19 tests. These tests are now being delivered to states, and Governor DeSantis of Florida can be seen demonstrating one here. As detailed in this New England Journal of Medicine article in September, the point of rapid testing is to capture infectious people earlier in their illness and intervene before others are infected. Less accurate tests are used to screen larger populations, more rapidly, multiple times and the reduced sensitivity of the test is made up for by repeated testing. So for populations like nursing homes, filled with high risk patients, repeated testing of employees and residents allows for earlier capture of infectious people and hopefully less disease spread.

It is important to note that these tests received emergency authorization based on testing in people who were symptomatic and that use of these tests for screening large groups of asymptomatic people, though supported by the government and scientific community, is not what the initial product testing and FDA approval was based upon.  So, much like rapid strep and rapid flu testing, these tests are useful but they are known to be less accurate. When accuracy matters, a follow up standard PCR test is still recommended.

Abbott ID NOW evidence:

  1. Coronavirus (COVID-19) Update: FDA Informs Public About Possible Accuracy Concerns with Abbott ID NOW Point-of-Care Test
  2. Performance of Abbott ID Now COVID-19 Rapid Nucleic Acid Amplification Test Using Nasopharyngeal Swabs Transported in Viral Transport Media and Dry Nasal Swabs in a New York City Academic Institution – PubMed
  3. Comparison of Cepheid Xpert Xpress and Abbott ID Now to Roche cobas for the Rapid Detection of SARS-CoV-2 – PubMed
  4. Comparison of Abbott ID Now and Abbott m2000 Methods for the Detection of SARS-CoV-2 from Nasopharyngeal and Nasal Swabs from Symptomatic Patients | Journal of Clinical Microbiology
  5. Comparison of Abbott ID Now, DiaSorin Simplexa, and CDC FDA Emergency Use Authorization Methods for the Detection of SARS-CoV-2 from Nasopharyngeal and Nasal Swabs from Individuals Diagnosed with COVID-19 | Journal of Clinical Microbiology
  6. Clinical Evaluation of Three Sample-to-Answer Platforms for Detection of SARS-CoV-2 – PubMed
  7. Evaluation of the COVID19 ID NOW EUA assay – PubMed
  8. How many are we missing with ID NOW COVID-19 assay using direct nasopharyngeal swabs? Findings from a mid-sized academic hospital clinical microbiology laboratory – PubMed

4) The White House Experience

The White House has been in the news due to a COVID-19 outbreak. Investigations of the White House testing protocol have revealed a heavy reliance on rapid Abbott tests and a lack of other protective measures. This particular outbreak brings several important lessons that are helpful examples to schools and businesses.

  • Rapid tests are not 100% accurate, as we discussed above. In addition, these tests were validated in symptomatic people early on in their infection and not tested for accuracy as screening methods for asymptomatic people. So we do not know the actual performance of these tests in the asymptomatic general public.
  • Rapid tests do not take the place of quarantine when someone is exposed. The CDC guidelines clearly state that people who are exposed can not end quarantine early by testing negative for COVID-19. They are to be quarantined and monitored for symptom development for a full 14 days. A negative test can be inaccurate or levels of circulating virus can be low at the time of testing, leading to false reassurance that someone is not contagious.
  • COVID-19 has airborne transmission. The White House outdoor ceremony in the Rose garden is thought to be the source of the outbreak. Attendees were spaced less than 6 feet apart and were not wearing masks. Despite everyone testing negative, an outbreak occurred. This proves the need for utilizing all of our mitigation strategies including mask use and distancing, even when outdoors. Outdoor air remains safer than indoor air because of the constant ventilation, but it is not safe enough to remain unmasked less than 6 feet away from people.

5) COVID-19 Treatments

President Trump’s COVID-19 treatment also brings to the media forefront the multiple treatments currently under investigation. We have discussed most of these in previous newsletters, but here is a quick summary of what we know he received.

  • Regeneron’s Antibody Treatment: This is a treatment consisting of a single cloned antibody found in the blood of people who have recovered from COVID-19. This antibody, found to be neutralizing against SARS-CoV-2, was cloned and is given as an infusion to people at risk for bad outcomes from COVID-19. To date, the company has performed limited phase 2 trials showing promise. The testing groups are very small (less than 300) but the limited release of data from the company suggests the treatment has reduced hospitalizations and death. Eli Lilly is also developing a similar drug and has applied for emergency use authorization based on limited phase 2 data. Both of these drugs show promise in preventing bad outcomes for those at the highest risk. Further study and data is pending.
  • Dexamethasone: This steroid has been in use for decades and is used for a multitude of medical reasons. A study published in the New England Journal of Medicine in July showed the drug reduced death and complications in patients requiring oxygen, while in the hospital. Since then, it has been adopted by the National Health Service in the U.K. and is routinely given to patients requiring hospitalization due to COVID-19 in the U.S.
  • Remdesivir: This antiviral drug also received emergency authorization from the FDA for use in hospitalized patients with COVID-19. However, it has been around for some time as an experimental therapy and was used to treat patients with Ebola, and was tested in the lab against SARS and MERS. The drug is not yet widely available and patients may be candidates to receive it as part of a clinical trial. A more recent multi-national study published this week in the New England Journal of Medicine found the drug to be beneficial because it reduced illness from 15 days to about 10 days, and reduced deaths by about 4%. The drug is taken as a 10 day course.

All of these therapies and others currently under investigation, bring hope that we will soon have multiple ways to treat patients with COVID-19, in addition to vaccines for prevention.

6) Flu Vaccines

It is that time of year and the seasonal influenza (flu) vaccine is available. We strongly recommend everyone who does not have a contraindication get the vaccine. There are multiple varieties so consult with your physician to decide which one is best for you. A recent article published by NPR suggests that there may be benefit from obtaining the live attenuated nasal flu vaccine. It is an interesting theory that speculates that live virus vaccines essentially “prime” the immune system for readiness and therefore may reduce symptoms and severity when infected with COVID-19. We have heard similar theories suggesting this is the reason why younger children do not display symptoms as often as adults, because they have been receiving multiple vaccinations more frequently. It is still theoretical. However, obtaining the flu vaccination is known to reduce symptoms, severity of illness, and hospitalizations form influenza. During a pandemic, all of these are good things.

7) Pandemic Fatigue

The World Health Organization released a statement this week discussing pandemic fatigue and methods to combat the problem. They theorize this may play a part in the case resurgence across the globe. It brings to light the tole of a pandemic on our daily lives and the cost of becoming fatigued or even numb to the continued pleas to be vigilant. It is certainly exhausting. We hope our efforts to monitor the “chatter” and focus the recommendations are helpful. It is very difficult to maintain the level of caution necessary to protect oneself against COVID-19 for such an extended period of time. Incorporating those strategies into everyday routines and teaching our children to do so as well, helps to prevent slip ups and provides a normalcy to these measures. This is surely something our children will look back upon decades from now with memories of masks, sanitizers, and distancing. We hope to be there with you, reminiscing about days gone, and remembering loved ones lost.

8) New York Cases Increasing

New York State has seen an increase in COVID-19 cases in specific regions. 20 zip codes were selected by Governor Cuomo as “hot spots” and increased restrictions have been put in place in those areas. If you have staff living in those areas, or students and parents commuting from those areas, a reminder about exposure is helpful. Use of public transportation, though unavoidable for some, increases exposure risk. That risk increases even more when there is a higher disease burden present in the community. Mask use, hand sanitizing, and distance are critically important. Reducing activities that may result in exposure, like eating in restaurants or even dining with friends, can also be helpful until control of the outbreaks in those areas is achieved.

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