At present we are testing for the Covid-19 virus. Swabs of the upper respiratory track are taken and a test is done which involves multiplying up the RNA in the sample. There are many false negatives since the virus tends to reside deeper down in the lungs so you may have the virus without it being detected. If the virus is detected, you and your contacts can be isolated, reducing the chance of transmission to others. But that is another story.
Here I want to examine the implications of testing for the antibodies to Covid-19. These are the substances that the body creates to neutralize any further incursions of the virus into your body. In other words, you are immune to at least this strain of C19 and possibly have some partial immunity to other closely related strains which may be produced by mutation of the virus. The tests for the Antibodies are being rolled out and hopefully they will soon be widespread and affordable. At present it is not known how long immunity will last in people who have contracted the disease. Contracting some diseases give you immunity for life, some for a lesser period.
So what is the value of being able to test for antibodies for this disease. In no particular order:
1. We will now be able to get a good estimate of how many people have had the virus but were a-symptomatic. Some present estimates are 4 to 5 a-symptomatic people for every one who gets sick. This will allow us to determine:
a) The true death rate from this disease
b) Why some people are a-symptomatic. Is it genetic, related to gut bacteria, connected with age, race, previous or present disease profile and so forth.
c) What the true rate of immunity in in the population.
d) At what rate of immunity does herd immunity become effective.
e) Who to give the vaccine to when it is available. No use wasting it on people who have had the disease (symptomatically or a-symptomatically) and hence are already immune to it.
2. Which people can now go back to work, look after people with the disease, be out and about rather than in lock down, shop in the super markets and so forth with no danger to themselves or to others. Here I would make a suggestion.
Give anyone who has tested positive for antibodies a photo ID card that they can show to the police or 'to whom it may concern' stating that they are immune.
These people can still transmit the disease just as any surface can but they are not factories spewing out massive numbers of viruses into their environment. They can start to get us up and running as early as possible. Even before the test for antibodies becomes readily available, people that have had the disease and are not OK can be issued such a photo ID card.
3. When a vaccine is rolled out, over time we will be able to see the relative effectiveness of having had the vaccine or having had the disease. For some diseases a better, longer lasting immunity comes from having had the disease.
Sadly the countries that have been slackest in controlling the spread of the virus will be the countries that can get up and running first. They will develop herd immunity earlier and the virus will die out in their countries. On the negative side, the cost of their poor response to the virus will be the death of many of their citizens who didn't have to die.
Here I want to examine the implications of testing for the antibodies to Covid-19. These are the substances that the body creates to neutralize any further incursions of the virus into your body. In other words, you are immune to at least this strain of C19 and possibly have some partial immunity to other closely related strains which may be produced by mutation of the virus. The tests for the Antibodies are being rolled out and hopefully they will soon be widespread and affordable. At present it is not known how long immunity will last in people who have contracted the disease. Contracting some diseases give you immunity for life, some for a lesser period.
So what is the value of being able to test for antibodies for this disease. In no particular order:
1. We will now be able to get a good estimate of how many people have had the virus but were a-symptomatic. Some present estimates are 4 to 5 a-symptomatic people for every one who gets sick. This will allow us to determine:
a) The true death rate from this disease
b) Why some people are a-symptomatic. Is it genetic, related to gut bacteria, connected with age, race, previous or present disease profile and so forth.
c) What the true rate of immunity in in the population.
d) At what rate of immunity does herd immunity become effective.
e) Who to give the vaccine to when it is available. No use wasting it on people who have had the disease (symptomatically or a-symptomatically) and hence are already immune to it.
2. Which people can now go back to work, look after people with the disease, be out and about rather than in lock down, shop in the super markets and so forth with no danger to themselves or to others. Here I would make a suggestion.
Give anyone who has tested positive for antibodies a photo ID card that they can show to the police or 'to whom it may concern' stating that they are immune.
These people can still transmit the disease just as any surface can but they are not factories spewing out massive numbers of viruses into their environment. They can start to get us up and running as early as possible. Even before the test for antibodies becomes readily available, people that have had the disease and are not OK can be issued such a photo ID card.
3. When a vaccine is rolled out, over time we will be able to see the relative effectiveness of having had the vaccine or having had the disease. For some diseases a better, longer lasting immunity comes from having had the disease.
Sadly the countries that have been slackest in controlling the spread of the virus will be the countries that can get up and running first. They will develop herd immunity earlier and the virus will die out in their countries. On the negative side, the cost of their poor response to the virus will be the death of many of their citizens who didn't have to die.
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