Provider Update for Saturday March 21, 2020
Saturday, March 21, 2020
JoAnn Wood MD, MHA, CMO- Baptist DeSoto
Lillian Ogari, Ph.D., MPH., Associate Professor of Microbiology BCHS
Amanda Comer DNP, RN
Stephen Threlkeld MD. Medical Director Infectious Disease Baptist Memorial Health Care
Coronaviruses are a large family of lipid-enveloped RNA viruses. These viruses are commonly occurring in Humans and many different species of animals, including camels, cattle, cats, and bats. Rarely, animal coronaviruses can mutate to infect humans and then spread between people such as with MERS-CoV, SARS-CoV, and now with this new virus (named SARS-CoV-2) COVID-19. The evidence on MERS-CoV and SARS-CoV demonstrated that those pathogens were more difficult to transmit than common influenza but were much more clinically dangerous than the flu. COVID-19 is a novel virus; hence, there is precious little scientific data available about the infections it has now caused in humans. There is also precious little herd immunity among humans to COVID-19. These infections were first discovered in China in late November –early December 2019 in and around Wuhan City in Hubei Province, China. The COVID-19 virus was able to efficiently infect thousands of Wuhan City residents in a matter of weeks leading to an epidemic. The CDC has substantiated that COVID-19 causes SARS-CoV-2, and that an individual infection can quickly lead to community spread. This epidemiologic pattern has been particularly observed in China, Italy, Iran, Spain and now in the U.S. The virus has now spread around the world and meets the WHO classification as a pandemic.
The SARS-CoV-2 virus is a betacoronavirus, like MERS-CoV and SARS-CoV. All three of these viruses have their origins in bats. The RNA sequences from COVID-19 infections in U.S. patients demonstrate a similar RNA sequence when compared to the sequence that researchers from China initially posted. This information strongly suggests a likely single, recent emergence of the novel virus arising from an animal reservoir. Early on, many of the patients at the epicenter of the outbreak in Wuhan City had some link to a large seafood and live animal market, suggesting animal-to-person spread. Later, a growing number of patients reportedly did not have exposure to animal markets, indicating community transmission via person-to-person spread. Within a matter of weeks from the first reported cluster of cases arising from the market-exposed patients, massive community transmission was reported.
Testing for the COVID-19 Virus
Current tests for COVID-19 consist largely of RT-PCR (Reverse Transcription Polymerase Chain Reaction) techniques. RT-PCR requires minute amounts of the RNA from a COVID-19 sample (i.e. nasal swab from a patient) to be amplified to allow adequate detection of the viral type and sequence. This, in essence, allows identification of the viral type even if there are relatively small amounts of RNA within the collected sample. The sensitivity and specificity of RT-PCR is extremely high with low risk of false positives or false negatives. Other test are available or are under development, but RT-PCR is the gold standard as of 3-21-20.
Early Virology Understanding of COVID-19
Like other coronaviruses, COVID-19 can be spread by contact with droplets by direct inhalation or by contact with a contaminated surface. Aerosol transmission is also possible. In a recent paper in the NEJM, researchers from Princeton found that the COVID-19 virus remained active at 3 hours in aerosol suspension and remained active for days on multiple types of contact surfaces including metals, plastics, cardboard and paper (reference). The virus can be inactivated with alcohol based and chlorine based cleansing agents and most cleaning agents approved for the healthcare setting are sufficient for use in decontaminating surfaces.
Preventing COVID-19 infections
Currently there are no approved vaccines to prevent a COVID-19 infection. A worldwide effort is underway to develop a vaccine. However, it is realistic to assume that widespread immunization could not begin until the earliest late 2020 or early-mid 2021. The COVID-19 virus has been shown to use Angiotensin converting enzyme 2 (ACE 2) receptors as a point of entry into the human cell facilitated by type transmembrane serine proteases (TMPRSS2). There are several drugs currently being tested which would target this pathway to prevent viral entry and possibly prevent overt infection.
The best preventive steps for avoiding COVID-19 infection is to limit one’s exposure to the pathogen. The most dangerous exposure is via direct transmission from an infected person via aerosol, droplet or surface contact. Avoiding large groups of people in close contact is imperative in preventing community spread of COVID-19. Avoiding close physical contact with others in the form of hugging, shaking hands, and kissing is also protective. In the healthcare environment every effort should be made to mask potentially infected patients, and for health care providers (HCP’s) to use proper application of the proper personal protective equipment (PPE). Careful hand hygiene using approved products and with soap and water can prevent transmission. Please see below.
Current Condition: 3-21-20
PREVALENCE IN USA AND OUR REGION
USA as of 3-19-2020:
COVID-19: U.S. at a Glance (CDC)
- Total cases: 15,219
- Total deaths: 201
- States reporting cases: 50
- US Territories reporting cases: 4
Cases of COVID-19 Reported in US, by Source of Exposure (CDC)
- Travel Related: 337
- Close contact: 321
- Under Investigation: 14,561
- Total cases: 263
- Total deaths: 0*
* According to Tennessee Department of Health (TDH) and Shelby County Health Department (SCHD), the highest number of cases have been reported in Davison County (101) and Williamson County (35) and Shelby County (30)
- Total cases: 80
- Total deaths: 1
- Total cases: 96
- Total deaths: 0
The USA, like countries across the world, has been quickly impacted largely due to mass transit of people around the globe who harbored the virus in an asymptomatic state of in an early symptomatic state. From what is understood at this time, there is little to no natural immunity to COVID-19 as it is a new variant of other coronaviruses. The population currently reported to be positive with the disease is likely to be a gross underestimation.
The Ro (This is a mathematical term that indicates how infectious a disease is. It is also referred to as the reproduction number telling you the average number of people who will catch a disease from only one contagious person.) is 2-4 which is similar to influenza. The Case Fatality Rate is reported to be 3.4%. (See comments below.)
So why all the hype? The main reason for immediate concern is that the virus has been able to spread very quickly and effectively suchthat there is a sharp spike in the numbers of individuals requiring admission and than others such that those who need hospital care are overwhelming hospitals – particularly with those who require ventilation. It’s about ensuring every person who needs care in the community will be able to receive it while we also are positioned to still provide care others in the community need. It is about ensuring that there is adequate supply by slowing demand through preventing community spread. We need all physicians to share these data.
This is a lesson we need to learn and prevent for COVID-19 patients and we can do this by following the CDC’s recommendations on Personal Protective Equipment. (See below)
Healthcare workers seem to have an increased risk of acquiring this virus and needing hospitalization. We believe one reason for this has been inadequate use of PPE. Studies have shown that when monitored, healthcare workers properly don and doff PPE only about 40% of the time. A second reason in this epidemic has been that hospitals have run out of PPE. Baptist is constantly working to ensure adequate supplies and will be updating you with modified plans when/if they are needed. The last reason may be that healthcare workers are exposed to a higher amount of virus particles because of what we do. Therefore, all of our hospitals and medical staff have been working to reduce touches and time with patients while also balancing the importance of providing excellent care.
The virus spreads without any symptoms (which is why it’s so effective at spreading quickly) and it is more contagious than most other viruses we have contacted. There is a metric known as the reproductive number (R0) used to measure how contagious an infectious disease is including viruses . The COVID-19 virus has an R0 number of 2.2 as compared to seasonal flu, which has an R0 number of 1.3. This means that a person infected with COVID-19 will infect 2.2 other people (Ying et al 2020).
Healthcare personnel caring for patients with confirmed or possible COVID-19 should adhere to CDC recommendation for infection prevention and control (IPC):
- Assess and triage patients with acute respiratory symptoms and risk factors for COVID-19 to minimize chances of exposure, including placing a facemask on the patient and placing them in an examination room with the door closed in an Airborne infection Isolation Room (AIIR) if available.
- Use standard precautions, contact precautions, and airborne precaution when caring for patients with confirmed or possible COVID-19.
- Perform hand hygiene with alcohol-based hand rub before and after all patient contact, contact with potential infectious material, and before putting on and upon removal of PPE, including gloves.
- Use soap and water if hand are visible soiled.
- Practice how to properly don, use and doff PPE in a manner to prevent self-contamination
- Perform aerosol-generating procedures, in AIIR, while following appropriate IPC practices, including use of appropriate PPE.
There are a variety of reports on the frequency of these symptoms so only the symptoms are listed:
- Upper respiratory symptoms (congestion, runny nose, etc.)
It is important to note that some patients present with gastrointestinal symptoms such as diarrhea, hematemesis and abdominal pain.
- Mildly elevated AST, ALT, LDH and TBili
- Low procalcitonin (May be elevated if a bacterial superinfection present)
- Elevated Ferritin
- Elevated IL-6
- Elevated CRP
CXR: Hazy, bilateral peripheral opacities.
POCUS: Numerous B Lines; pleural lining thickening; consolidations with air bronchograms.
CT: Ground Glass Opacities (Crazy paving) bilaterally, most commonly
There are no proven effective treatment regimens. However, there are reports of efficacy with a number of medications including plaquenil, remdesevir, camostat mesylate and ECMO as examples. Our infectious disease physicians and our pharmacists at Baptist are vigorously reading these reports and determining what we can supply for patients who present to one of our hospitals.
Corticosteroids are not recommended for use in these patients. Ibuprofen should be avoided according to the CDC.
WHAT CAN PHYSICIANS DO?
- Properly don and doff PPE.
- Protect your families by wearing your own scrubs to the hospital and taking them off and carrying them back home in a plastic bag which is immediately thrown into your washing machine.
- Wipe down your work surfaces with appropriate cleaning materials regularly.
- Knowledge is power. Check this website for evidence based reports. Up-to-Date has a terrific page which is regularly being refreshed.
- If you identify a concern, address it with leadership, as opposed to with a frontline employee in order to best correct the problem and to reduce anxiety of frontline personnel. You are a leader because you are a physician.
- If you interact with a patient who eventually tests positive for the virus, it is reasonable for you to check your temperature twice daily and to contact employee health if your temperature is above 100.4 degrees Fahrenheit. Otherwise, you should continue to work. If you were not wearing proper PPE, please contact employee health for instructions.
- If sick, please stay at home.
Liu Y, Gayle AA, Wilder-Smith A, Rocklöv J. The reproductive number of COVID-19 is higher compared to SARS coronavirus. J Travel Med. 2020;27(2):taaa021. doi:10.1093/jtm/taaa021
Cynthia Liu, Qiongqiong Zhou, Yingzhu Li, Linda V. Garner, Steve P. Watkins, Linda J. Carter, Jeffrey Smoot, Anne C. Gregg, Angela D. Daniels, Susan Jervey, Dana Albaiu. Research and Development on Therapeutic Agents and Vaccines for COVID-19 and Related Human Coronavirus Diseases. ACS Central Science, 2020; DOI: 10.1021/acscentsci.0c00272