Blog #38: Immunology’s role in pandemics, infectious disease, and COVID-19 (Part 4: Therapy)

Care for coronavirus patients is supportive in nature and may include rest, supplemental oxygen, fluid administration, and, for critically ill patients, being managed in intensive care units and receiving rescue therapies such as extracorporeal membrane oxygenation (pulmonary ventilation). Stringent infection control is critical to prevent transmission to caretakers, healthcare workers, and other patients. Personal protective equipment (PPE) including surgical or procedure masks, gown, gloves, and face shields) are indicated during the treatment of all coronavirus patients, and such protocols for droplet-spread respiratory viruses that are part of hospital infection control practices. Masks as preventive care for all persons are indicated, but public (and even political) resistance has proven to be an obstacle in this simple, but most valuable protective measure.

General measures

• Test all populations, especially those suspected of infection (tests listed below);

• All positives should be isolated and “contact traced” (“if possible”) to identify “patient 0” and/or persons who may have come into contact with the infected person. They too should then be tested;

• Shelter-in-place or “self-isolation” (remain in your home with only absolutely necessary outdoor activities);

• Social distancing (separation of > 6 to 10 feet between people);

• Avoid gatherings of more than 5 to 10 people;

• Wash your hands copiously and frequently;

• Face masks (at first CDC and surgeon general suggest for use only if infected, now it’s strongly recommended for full-time use - N90 masks preferable);

• If symptoms occur (fever, cough, chills, aches, and pains), get tested and if positive, self-quarantine for a minimum of 14 days and retest 2X before resuming normal activities;

• If symptoms advance over 2 to 3 days, seek medical attention;

• Mitigation: process includes procedures and policies to reduce risks of infectious spread;

• Modeling

  • Study the mechanisms by which disease is spreading (i.e., investigative epidemiologic and public health analysis);

  • Monitor (graphically) through testing positive case volumes, death rates, and other vital statistics;

  • Hospital admissions;

  • Intensive care admittance;

  • Extracorporeal membrane oxygenation (pulmonary ventilation)

Treatments

It appears that SARS-CoV-2 infection has two phases. The early phase includes the infectious stage (approximately 3 to 9 days) where the virus is replicating followed by the later stage (7 to 21 days) where the disease is driven by an exaggerated immune/inflammatory response to the virus. This is the phase that leads to tissue damage, organ failures, and oftentimes, post-COVID syndrome or long haulers syndrome. Based on this understanding, and as has been shown in clinical outcomes, antiviral therapies would have the greatest effect early in the course of time and are unlikely to be more beneficial in the later stages (beyond 5 to 7 days) of the disease.

If I may, I would like to ask you over the coming week to do a quick review of Blogs #20 through 23, 25, 26, 31, 32, and 34, all of which provide the basic science and applications of the immunotherapeutic drugs and procedures. Almost all of them are being used in the treatment of COVID-19 (and many other infectious diseases).

Discussion Questions:

1. Among preventive public health measures in the control of COVID-19, what is the simplest, yet too often neglected, procedure?

2. It appears that SARS-CoV-2 infection has two clinical phases. Can you identify the more significant immunopathology in each phase?