Global COVID-19 cases exceed 1.7 million confirmed cases, and a staggering daily growth rate.
Patrick Ivan Borgen, MD, Chairman, Department of Surgery Maimonides Medical Center Brooklyn, New York
Global COVID-19 cases exceed 1.7 million confirmed cases, and a staggering daily growth rate. In the short amount of time between the first and second installment of this series, the number of American deaths from COVID-19 has doubled.
Reflecting this in our neighborhood of Borough Park in Brooklyn, New York, we now have more than 400 COVID-19—positive patients, nearly 200 critically ill patients on ventilators. Dozens of our healthcare workers at Maimonides Medical Center in Brooklyn have contracted the virus and many more are expected to. The actual risk of dying from a COVID-19 infection is difficult to calculate, as the denominator in this time of restricted testing is unknown. However, best estimates put the number between 0.8% and 3.5%, with some wide variations among subgroups.
NYC Health reported, as of April 3, 2020, that the median age at diagnosis is 49 years old.1 Only 2% of cases occur in individuals younger than 17 years old, and 10% of cases occur in adults over the age of 75. Males have a somewhat higher incidence than females (55% vs 45%). One New York resident who is younger than 17 years old has died of COVID-19. There are twice as many deaths in the ≥75-year-old group (n = 853) than either those who are 65 to 75 years old (n = 461) or those who are 45 to 65 years old (n = 442). Males with underlying medical conditions have the highest risk of death from this virus.
Moreover, on April 3, 2020, New York reported 562 deaths in 24 hours with 14,810 patients hospitalized; this was an increase of 1427 deaths in 24 hours. Of the hospitalized patients, 3731 were in intensive care units, which was an increase of 335 patients in 24 hours.
What Do We Know About the Biology of COVID-19?
COVID-19 is a large, positive-stranded RNA virus in the coronavirus class. Its name is derived from the fact that, under an electron microscope, it has a crown-like appearance that is created by the presence of spike-shaped glycoproteins on the envelope. It is the seventh coronavirus to circle the globe—the earliest of which dates back to the 1960s. COVID-19 is a Baltimore Classified IV virus that can produce message in a positive direction. When put into context, viruses such as HIV or AIDS, which are Baltimore Classified VI, require reverse transcriptase to message in a negative direction back to complementary DNA before producing signal.
Genomic characterization has shown that it is most likely that rodents and bats are the gene sources of COVID-19. The virus contains open reading frames (ORF) that serve as templates for the production of sub-genomic mRNAs. Some ORFs code for structural proteins, and a frame shift in ORFs can guide the production of several papain-like proteases for creating non-structural proteins (NSPs). One group of NSPs is able to block the host’s innate immune response.
Included in the COVID-19 structure is a fusion peptide moiety with a transmembrane and cytoplasmic domain that is highly conserved making it an attractive target for antiviral—anti-S2—compounds.2
There are 4 major classes of these viruses and COVID-19 belongs to the beta-CoVs category. Its form is primarily round or elliptic, and often demonstrates a somewhat pleomorphic form with a greatest diameter of approximately 60 nm to 140 nm. This virus is sensitive to ultraviolet rays and heat, although it is unknown what impact the change of season will have on rates of transmission.
Moreover, these viruses can be effectively inactivated by lipid solvents including ether (75%), ethanol, chlorine-containing disinfectant, peroxyacetic acid, and chloroform, but the data for chlorhexidine are not consistent. Until this is resolved it is safest to use products that contain chlorhexidine with alcohol. The virus does not aerosolize, but it is easily transmitted in droplet form. The use of protective face masks is intended to be droplet protection first and foremost, rather than purifying 100 nm particles as their primary role. Ironically, against a complex, highly virulent and complex microbe, handwashing with soap and mechanical cleansing is an effective prophylaxis against droplets containing the active COVID-19 virus.
Editor’s Note: This column is the second in a series by Patrick I. Borgen, MD, on the COVID-19 pandemic and how it is impacting the healthcare system.