BREAKING NEWS: Hyde County announced today its first confirmed case of COVID-19, according to OBX Today. Hyde County, which includes Ocracoke Island, has not identified where the infected person is located. It has only said that he or she is in isolation, and that the county is tracing all close contacts the person has had.
JUST A FEW SCIENTIFIC FACTS . . .
As you all know by now, a coronavirus is a category of virus that is so named because it is covered with crown-like spikes, like the U.S. Centers for Disease Control and Prevention’s ubiquitous illustration above.
The new coronavirus that has caused the COVID-19 pandemic is severe acute respiratory syndrome coronavirus 2, or SARS-CoV-2, for short. COVID-19 is the respiratory illness that SARS-CoV-2 causes.
SARS-CoV-1, which emerged in China in 2002, is the human coronavirus most closely related to SARS-CoV-2.
SARS-CoV-1 infected over 8,000 people in 2002 and 2003, but it was contained before reaching anything approaching the spread of SARS-CoV-2. It was known simply as SARS. Eventually, its origin was confirmed to be zoonotic (animal to human)—traced to a family of bats commonly known as horseshoe bats.
You may have heard about Middle East respiratory syndrome, called “MERS,” which is caused by a betacoronavirus, which is a genus of the coronavirus.
MERS-CoV emerged in Saudi Arabia in 2012, and it, too, derives from bats. Camels are believed to be involved in the spread of MERS-CoV to humans, but it is not clear how.
Unlike SARS-CoV-2, MERS-CoV is not readily transmitted from human-to-human. MERS transmission typically occurs only after close contact with severely ill people. There have been outbreaks of MERS on the Arabian Peninsula and in South Korea since 2012, but they have been contained.
The Spanish flu pandemic of 1918-19, which you may be reading about these days, was caused by a subtype of the influenza A virus, known as H1N1 influenza virus. A new strain of swine-origin H1N1 virus caused the swine flu outbreak of 2009.
The Spanish flu—apparently so-named because Spain was reporting news of the outbreak, when other nations were not—was an unusually severe and deadly strain of avian (bird) influenza.
Other facts that have been reported in the medical literature include:
CELL ENTRY: The new coronavirus binds to target human cells through the angiotensin-converting enzyme 2 receptor.
A receptor is a protein molecule in a cell or on a cell that functions as a lock or gateway. The S protein of SARS-CoV-2 acts as a key to unlock the receptor and enter the cell. (And that is as far as I will go with protein biochemistry.)
Receptors bind with substances such as hormones, neurotransmitters, drugs, and antigens (toxic substances), including viruses.
SARS-CoV-1 also entered the cell through the same receptor.
Some of you may recognize the angiotensin-converting enzyme (“ACE”) because you take an ACE-inhibitor for high blood pressure and/or other heart-related conditions. This enzyme is part of your body’s renin-angiotensin system, which regulates blood pressure and otherwise acts to maintain homeostasis, which you may think of as an equilibrium in your physiological processes.
According to The New England Journal of Medicine’s (NEJM) “Journal Watch” of medical news about SARS-CoV-1:
“High risk for severe COVID-19 disease has been assumed to be driven largely by waning innate immunity that comes with advanced age, but younger patients with cardiovascular disease or hypertension may have unappreciated risk.”
INCUBATION TIME: The mean incubation time for COVID-19 is about five to six days, according to a study published March 10 in The Annals of Internal Medicine.
The authors studied the case records of 181 patients who had visited Wuhan, China, or been in contact with an infected person before becoming symptomatic and testing positive for COVID-19 between Jan. 4 and Feb. 24, 2020. Fewer than 2.5 percent of these patients experienced COVID-19 symptoms within 2.2 days of exposure to the new coronavirus. Within 11.5 days of exposure, 97.5 percent of them were symptomatic.
These findings confirm the CDC’s current guidelines for quarantine.
According to the authors, the virus is “highly contagious” and is “primarily spread by droplets.” It is now well-known that asymptomatic or mildly symptomatic people can transmit the infection.
COMMUNITY TRANSMISSION: A community transmission of the virus is said to occur when the source of the infection is not known. The N.C. Dept. of Health and Human Services announced last week the first case in North Carolina of a community transmission of COVID-19. The person lives in Wilson, N.C., and is in isolation.
Community transmissions make the containment of the viral infection much more difficult. These are people diagnosed with the virus who are not in a high-risk area and have not been known to have any contact with other confirmed cases.
DR. ANTHONY FAUCI, director of the National Institute of Allergy and Infectious Diseases, remains The Beacon’s source for reliable information and trustworthy advice during this viral outbreak. (In my earlier life as a medical book author, I had the pleasure of communicating with Dr. Fauci, a brilliant physician-scientist and a kind and personable man.)
But Dr. Emily Landon, an infectious disease specialist at the University of Chicago medical school, made quite a splash yesterday at a news conference with her straightforward, clear, and urgent appeal to people to stay home. You may read about Dr. Landon’s address and hear some of it here:
Illinois is one of three states that have imposed stay-at-home orders on their populations. The others are New York and California. (Update 3/22/20: Connecticut and New Jersey also have imposed such orders.)
Ann G. Sjoerdsma, 3/21/20