Tag Archives: Los Angeles study of coronavirus antibodies

The very good news from New York

Today’s news from New York is very good indeed.   But first a joke

If one man tells you that you look like a horse

Ignore him.

If a second man tells you that you look like a horse

Pause and consider

If a third man tells you that you look like a horse

Buy a collar


The very good news from New York is that nearly 1 in 7 New Yorkers has antibodies to the new coronavirus.

For those not sure what having an antibody to the virus means as opposed to having the virus itself — see the explanation after the **** at the end of the post.

The New York study is the third one this week.

Study #1 was from Santa Clara County California, by people from Stanford which is located there.  Briefly, the authors advertised for people to be tested for antibodies (hardly a random sample).  They projected that about 4% of the people in a 2 million population county having antibodies to the new coronavirus.

To say the study was not universally loved is an understatement — https://statmodeling.stat.columbia.edu/2020/04/19/fatal-flaws-in-stanford-study-of-coronavirus-prevalence/


The Stanford one will likely have to be retracted as it’s been widely reported that there were severe methodological errors and even some basic math errors in the analysis. Also, the current antibody tests are essentially worthless given the high false positive rate (I believe the CEO of Roche made that exact claim today).

The joke tells us to Ignore him.  

Study #2 was from LA and also found that about 4% of the study group had antibodies to the virus  Unlike the Stanford (SF) study — The LA study was composed differently in that its 863 adults were selected through a market research firm to represent the makeup of the county.

A friend  sent me the following “Last week I attended (virtually) a Princeton talk by Prof. Edward Felton dealing with COVID-19 pandemic issues.  Prof. Felton mentioned in his talk that the SARS-CoV-2 antibody tests have about a 5% false positive rate (and likewise, about a 5% false negative rate.  If this is true than the 4% antibody prevalence measured in the California tests is meaningless, right?”

The joke tells us to pause and consider

Study #3 Today’s study is from New York State—- here’s a link –https://www.cnbc.com/2020/04/23/new-york-antibody-study-estimates-13point9percent-of-residents-have-had-the-coronavirus-cuomo-says.html.

The State randomly tested 3,000 people at grocery stores and shopping locations across 19 counties in 40 localities to see if they had the antibodies to fight the coronavirus, indicating they have had the virus and recovered from it. With more than 19.4 million people residents, according to U.S. Census data, the preliminary results imply that at least 2.7 million New Yorkers have been infected with Covid-19.

Buy a collar

All 3 studies are saying the same thing — most people aren’t terribly bothered by the virus.  In another context the following was said “It’s hard to argue with data. We’re scientists. We pay attention to data, we don’t try to un-explain them.”

How can I say that the news is good?  After all,Governor Cuomo is right; the numbers are horrible — 19,453 fatalities and 263,754 cases in the state. But the numbers also mean that the overall mortality is under 1% of those who have been infected with the virus.

This means that we are far closer than we thought to relaxing the restrictions on personal and economic activity than we thought, and that most people are naturally immune to severe complications of the virus.

Addendum 24 April — Today’s Science has critiques of study #1 and study #2 and several more (but not including the NY study) — here’s the link https://science.sciencemag.org/content/368/6489/350 — Not mentioned in the article is the fact that all the studies point the same way — at least a 10 fold increase in the percentage of antibodies vs. the percentage of patients in whom the viral genome can be found.


The 263,754 ‘cases’ in New York State, were determined by finding the actual genome (RNA in this case) of the virus in a person.  It’s like seeing a real bear which can do you some damage.  Antibodies to the virus are made by an individual who has been infected by the virus.  Antibodies (proteins) and genomes (RNA) are completely different chemically.      Antibodies are like seeing the tracks of the bear without the bear itself.