Herd Immunity and Epidemiology


My husband’s birthday is on April 1st. I let my relatives
know that his birthday was coming.

So, everybody called him to say for” Happy Birthday!”
on April Fool Day.

One of the callers was my husband’s cousin who is in
his late 70s. But he is still working at one of
the medical schools in Philadelphia as a half time
researcher in the field of radiation biology.

Since they have not seen each other in more than fifteen years,
they talked and talked for almost three hours. We always laughed
that the family has diarrhea of the mouth.

One of the topics they talked about was Coronavirus. Since
his cousin is a retired medical school professor,
he talked about herd immunity and coronavirus.

My husband found a study on herd immunity and coronavirus
in a MIT Technology Review after their long conversation on his
birthday. One of the topics they talked about their three hours

The article is written by Antonio Regalado and the title is
“What is herd immunity and can it stop the coronavirus?”

I will summarize this article:

• Corona virus could end up infecting about 60%
of the world’s population.
• The UK government was pushing the idea of
building up group immunity.
• The coronavirus is new, so it doesn’t appear
that anyone is immune to it: that’s why it spreads.
• The coronavirus most similar to the virus causing
COVID-19 is the one that causes SARS.
• The herd immunity multiple in a given population
goes like 1,2,4,8,16 …
• If half the population are immune, half of those
infections won’t happen again.

The conclusion of this story is that social isolation does not build up
herd immunity.

But, now, Boris Johnson, Prime Minister of
the United Kingdom got a coronavirus and he was
hospitalized and his pregnant
fiancé got a coronavirus, too. So, I don’t know
this theory of herd immunity.
But, closing down a whole world means that
no one is making money and consequently,
it’s really bad for our economy.

I will just continue to do my physical exercises including
housecleaning, laundry and walk.

Cooking everyday. Go to the grocery stores once or
twice a week. Checking money more carefully.
Definitely, my lifestyle has changed.

I heard that the airline companies slowly start to fly into
other countries to start the business. Ventilations are
coming from China by air. But, remember very slowly.
Wait and see.

My husband’s birthday made us think about Coronavirus from
a different angle from a different source.



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