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Could You Have Already Been Infected with COVID-19?

Dr. Don Colbert – A few new studies are shaking up the COVID-19 infection numbers and causing quite a stir among analysts. These surveys, which were performed on the opposite ends of the country, suggest that many more people have already been infected with COVID-19. Many of the infected participants were either asymptomatic or very mildly symptomatic and did not know they had it (1). The numbers may suggest that our population immunity is growing, and the death rate is much smaller than previously thought. Could you be one of the ones who have already been infected with COVID-19?

Here are the details of the preliminary surveys, the critiques of the science behind them, and what they suggest as more and more evidence mounts to help us understand COVID-19.

3 Studies to Estimate How Many Have Already Been Infected with COVID-19

In Santa Clara County, which has a population of 1.9 million, researchers studied the blood serum of 3300 participants (2718 adults and 612 children) to detect COVID-19 antibodies. These antibodies are detected if a person has been infected with COVID-19, whether the virus is currently active or not.

Based on the positive antibody tests, 2.49% and 4.1% of this population have been infected.

And, this makes some sense. Since tests have been in very short supply, and the vast majority of those tested have been high-risk or had moderate to severe symptoms, it’s quite possible that many people with a much milder or no symptoms have had it without being counted.

California Study #2. The University of Southern California (USC)

In Los Angeles County, which has a population of 10 million, researchers found that 2.8% to 5.6% of those tested were positive for COVID-19 antibodies. This was 28-55 times more than the incidence that has been calculated from positive tests by health officials.

New York Study

Three thousand people were also tested at random in New York to estimate the actual infection rate. Public health officials found that 21% from New York City tested positive, 17% on Long Island, 12% in Wescheckter and Rockland Countries, and less than 4% in the rest of the state.

The participants were found at grocery stores and big-box stores. The blood samples were tested over 2 days, using tests the state felt confident in as reliable.

If these numbers are extrapolated throughout the state, as many as 2.7 million may have already had COVID-19 without knowing it.

Critiques and Shortcomings of the Studies

Of course, there’s a gold-standard for studies, with double-blind controls, calculations to adjust for variables, and comparisons to previous studies.

All of this is difficult in real-time science, with a deadly novel virus on the loose.

These studies definitely have serious shortcomings. They include:
  • Motivated participants. The Santa Clara participants were recruited with Facebook ads. They were motivated to get out and get tested, which may mean they suspected they had had the disease. On the other hand, the New York participants were out shopping, which may mean they were not fearful of being infected and spreading the disease.
  • Population Control. The population of participants in the Stanford study was not controlled for age or race. The USC study used a firm to recruit participants, and it did represent the ethnicity of the population well. The New York study gathered participants at random, and not based on population age or ethnicity.
  • These studies have not been published or peer-reviewed. The Stanford study is considered a pre-review, and the USC results were simply stated in a press release.
  • The tests themselves have not been FDA-approved, and may not be as sensitive to the antibodies as needed for a reliable conclusion. However, the officials and researchers using them were confident in their results.
  • Small sample sizes. Great studies typically have very large sample sizes. These studies and surveys only represented a few thousand people.
  • Inconclusive. It’s difficult to derive conclusions from these studies based on small sample size and the difficult-to-reach herd immunity numbers likely needed. It’s been estimated that 67% of the population is needed for herd immunity of COVID-19(2).

These shortcomings are serious and need to be noted when looking at these studies. However, in a time when quick science and decision-making are warranted, even less-than-optimal studies can shed light.

Could You Have Already Been Infected with COVID-19?

Could you have already been infected with COVID-19? Maybe. It’s possible that 3%-21% of the population in different areas has been infected.

However, it’s very difficult to say based on symptoms. During the first few months of the year, many people experience respiratory symptoms from colds, cases of flu, other respiratory infections, allergens, and more.

The most common COVID-19 symptoms continue to be respiratory-related, along with headaches, muscle aches, fatigue, possible digestive issues, and recently reported discoloration of fingers and toes in children.

But, since the majority of cases may be asymptomatic, these symptoms are not necessary to indicate possible infection. It is possible that you have already been infected with COVID-19. Until widespread testing is available, we can only speculate and continue to gather data.

Bottom Line

We are getting new information daily on the novel virus COVID-19. While these studies are not fool-proof, they are mounting. They may give us enough data to make smart decisions as we move forward as a country, especially as many head back to work. Or, they may give us the wrong information. Time will tell. They are interesting nevertheless and may offer some hope that immunity is growing and the risk of death is lower than first believed.

To read the original article click here.

For more articles from Dr. Colbert click here.

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