We have seen how devastating the coronavirus can be for children, especially if they are obese. It can leave kids needing heart and lung transplants. We don’t want them to catch it, or to pass it on to others. But what is really known about transmission? Backing up a step, what is actually known about the identification and diagnosis of this potentially deadly disease?
Currently, there is a lot of discussion about how COVID-19 is transmitted, and to make any sense of it, knowing something about the two kinds of testing is helpful. One kind determines if the person has an active case, and another seeks to learn whether they ever had it.
William F. Marshall, III, M.D., of the prestigious Mayo Clinic points out, significantly, that no test is 100% accurate. For instance, there is such a thing as a false-negative result, which means a person tests negative when actually they are infected with COVID-19.
Two tests define whether a person is in active disease mode. The familiar swab up the nose uses the PCR (polymerase chain reaction) technique to detect the genetic material of the virus. Dr. Marshall says,
Molecular tests are considered very accurate when properly performed by a health care professional, but the rapid test appears to miss some cases.
The antigen test uses a nasal or throat swab and detects proteins that belong to the virus. It is more practical than PCR for mass testing, but not as dependable. Dr. Marshall says, “A positive antigen test result is considered very accurate, but there’s an increased chance of false negative results.”
From the army base at Fort Benning, GA, comes a disheartening anecdote about testing. Out of a batch of 640 new recruits who arrived for basic training, 636 tested negative. The four individuals with positive results were removed. Just over a week later, 142 of the previously negative troops now tested positive.
Did the patient ever have COVID-19?
Antibody testing uses blood to learn if a person had developed antibodies against the disease, and it comes with a couple of huge caveats:
If you have testing too early in the course of infection, when the immune response is still building up in your body, the test may not detect antibodies… [T]he World Health Organization cautions that there’s a lack of evidence on whether having antibodies means you’re protected against reinfection… The level of immunity and how long immunity lasts are not yet known.
Even if a person indubitably had coronavirus, and is full of antibodies, there is no consensus on whether the antibodies will stick around and prove useful.
A big surprise
We thought we knew that children are not very susceptible to COVID-19. As it turns out, that conclusion might need to be re-examined, in the light of deaths that were treated as routine, or at least as not justifiably troubling, in the days before Americans heard of the disease. There is new information every day about every aspect of it, and a very disturbing article was published just two days ago.
February 6, 2020, was when a death was first identified as being caused by the coronavirus. California’s Governor Gavin Newsom asked for a retrospective look at deaths in the weeks previous to that date, and things became interesting.
(To be continued…)
Your responses and feedback are welcome!
Source: “How do COVID-19 antibody tests differ from diagnostic tests?,” MayoClinic.org, undated
Source: “8 days after quarantine and testing negative, 142 Fort Benning soldiers test positive for COVID-19,” ConnectingVets.radio.com, 06/01/20
Source: “Mysterious deaths of infants, children raise questions about how early coronavirus hit California,” LATimes.com, 06/21/20
Image by Megan Mason/CC BY 2.0