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September 3rd,2020


It is the first week in September and many of you are gearing up for opening next week.  There have been a few developments you may have heard about, that are summarized here for you.


PCR tests, which are the standard nasal swab tests we have been using since the start of the pandemic. have come under fire recently. These tests search for the presence of genetic materials for the SARS-CoV-2 virus that causes COVID-19. The tests go through multiple “cycles” with each patient sample. Each cycle provides another opportunity for the test to detect any virus present. The more “cycles” you run, the better the test detects lower concentrations of virus. That means that someone with very little virus present in their nose, would still test positive given enough “cycles”.  The number of “cycles” is something that is not published with a test result. However, recently physicians have been arguing that this piece of information would be helpful to ascertain how contagious someone might be. The theory goes that anyone requiring more than the typical 30-35 cycles to detect a virus, might have such little virus present as to be considered “not contagious”.  However, we don’t know what the most accurate number of cycles would be since there are no published studies on this measure. Additionally, a single test with a low concentration of virus doesn’t inform us if the patient is at the beginning of an infection and expected to have increasing virus levels (viral load), or at the end of their infection and clearing the virus. So, although some will find this discussion interesting, it remains something potentially helpful to researchers and epidemiologists and not something that will effect daily use of the test, yet.

Additionally, because of the criticism of PCR tests, others have suggested that antigen tests should be utilized more often. The US government recently invested in a large quantity of these tests. These are typically less accurate, about 80%-89%, and are sold as “rapid” tests taking 15-30 minutes to give a result. Newer products approved by the FDA in this category, like the Abbot BinaxNow, claim to be more accurate with a false positive rate of 1.5% and a false negative rate of 2.9%. In the past, we have recommended against use of these tests for students because of their inaccuracy. There is a role for them when testing large numbers of people regularly. A single person is unlikely to have a false negative test multiple times in a row. In that scenario, these tests are more useful. However, for our purposes, a single sick student who is going to get only one test, should get the most reliable and accurate test. Until now, that has been the PCR. This is still the test we recommend. However, as new data is released about new products, like the Abbot BinaxNow, other options may become acceptable.

CDC COVID data release

The CDC publishes provisional death counts and statistics obtained from death certificates. The report is updated daily and provides an abundance of information. Recently attention has been drawn to the statistic showing only 6% of certificates have COVID-19 listed as the primary cause of death, and 94% have other conditions listed. Some have interpreted this to mean that the 171,000 deaths attributed to COVID-19 to date are inaccurate and that COVID -19 is less lethal than we are being told. This is incorrect. It is common and expected for death certificates to list all co-morbid conditions, that is those that may have played any role in the death. Chronic illnesses are commonly listed, such as hypertension and diabetes. In addition, conditions caused by COVID-19, such as sepsis, stroke, and renal failure, are also listed individually. This information becomes a valuable repository of conditions that increase the risk of death from COVID-19. It should not be interpreted as a false claim of death by COVID-19 when other conditions are present.

CDC Prepares States for Vaccine

The CDC recently sent guidance to states regarding the distribution of a COVID-19 vaccine. The guidance includes two different vaccines, which reporters are stating, bare striking resemblance to the vaccines currently in testing by Pfizer and Moderna. In addition, the CDC and National Institute of Health sponsored a publication from the National Academies of Science, Engineering, and Medicine. This report details an “equitable” distribution method for a vaccine. At the heart of all this information is the notion that the vaccine(s) should be distributed first to those who need it most. There is discussion of providing it first to the elderly, those in nursing homes, healthcare workers, and essential workers. You will recall that a week ago teachers were added to the list of essential workers. That means teachers would be included in the early distribution of the vaccine, if they choose to take it. Much is still unknown and these steps are necessary in order to develop a process of distribution before the vaccine is available. Drug manufacturers and Dr. Fauci have been quoted as saying a vaccine may be ready by October, November, and “the end of 2020”.  Russia and China have both granted vaccine makers approval without completing phase 3 trials. This is unusual and something that the FDA has spoken out against. However, if preliminary data from phase 3 trials is truly overwhelmingly positive (yet to be determined), a similar approval may occur in the US. Currently, it is too early to speculate.

Sewage and COVID-19

We have talked about the limited data from studies on toilets and the aerosol generated by flushing. Most have recommended simply closing the toilet lid and perhaps redesigning toilets to reduce this unfortunate effect. More studies are being published about sewage testing and COVID-19. These newer studies have a different focus. They are utilizing sewage testing to follow virus levels in a large population, like a metropolitan area. In hopes of detecting improvements or spikes in viral activity sooner, some sewage plants are experimenting with testing of samples and quantifying virus presence as an early warning system that infections are on the rise. Though this does not have to do with toilets and aerosols, it does prove that the virus is detectable in sewage.

NYC Testing Teachers and Students

The NY City mayor announced this week that the city will be testing 10 percent of all teachers and students for COVID-19 on a monthly basis. They plan on obtaining nasal swabs from students and faculty for the tests. According to the NYTimes, the costs range from $70-90 per test, costing the city up to $10 million a month. Coupled with this plan was a delay to re-open public schools as details of the testing are arranged.

Website Updates

The Admin EM website has a new look to the Q&A section (login required). Hopefully you find this easier to read. The search box at the top of the page is the best way to search the titles and content of the 44+ questions posted there. New questions are added regularly. Additionally, a new page for video tutorials (login required) has also been added. Clips from training videos will be placed here. Currently included are videos on: use of gloves, use of masks, and how to drink form a water bottle with a mask on.

That’s a lot of information. Thanks for reading all the way through. Next week will bring new challenges and we look forward to helping you through them.


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