Japan to start virus antibody tests on 10,000 people in June

Please beware of reliability issue on antibody tests. The level of accuracy varies depending on test kits. For a survey, tests should also be randomized.

"We will confirm how much immunity the entire community has acquired and utilize the data to prevent the virus spreading in the future," Kato said at a press conference.

There is no evidence yet that the presence of antibodies to SARS-CoV-2 confers immunity to subsequent infection.

There are two types of antibodies, lgM and lgG.

lgM usually confers only a short term immunity (measured in days to weeks), and lgG may confer a longer immunity if lgM are also present (measured in months or years).

These are two separate tests. But again, we do not know if any immunity is conferred at all, but some may be likely if both are present.

This is such elementary biology that I'm shocked to read the quote above. I can only think that the message is either meant to give people a false sense of security, or Kato (an economics major) has no one competent giving the minister epidemiology advice.

One more fact is that there is no evidence that corona viruses are seasonal. Influenza is not a corona virus.

There is other US false reporting that states in the US that reopened early have lower rates of infection than states who have no yet opened, based on a report by JP Morgan, who are only concerned about the financial impact to themselves. Infection rates are low from less testing and people living in the states that reopened early have not ventured out much.

Retail stores and restaurants are not busy at all because the majority of people are smart enough to understand that they are still at risk and have chosen to socially distance, travel less and wear masks.

Local authorities will conduct the tests and send blood samples to the central government for analysis.

I can already foresee what the outome of the analysis is.

Wuhan intends to do pcr testing of the entire 14M population in 10 days and LA also will test everyone that is 4M people to get a grasp of the rate of infection. I guess the above 2 cities have never heard of Antibody test.

According to a recent study, it does appear that reinfection is unlikely:

https://m.youtube.com/watchv=uatmbgk__tg

Many people are immune to it already and don't even know it. I think testing for antibodies is an excellent idea, I hope they make it part of the yearly medical.

And this study:

https://www.sciencedirect.com/science/article/pii/S1074761320301813

Testing 14 recovered people for antibodies, only one person did not have significant long term IgG antibodies; hopefully, they'll figure out why he/she couldn't produce them. All of the other 13 had these neutralizing antibodies.

There is no evidence yet that the presence of antibodies to SARS-CoV-2 confers immunity to subsequent infection.

Yes there is. What we don't know is for how long. Recovering patients are not reinfected even in wards full of acute patients, that is enough to conclude immunity is being developed. It being related or not to antibodies is irrelevant for this.

lgM usually confers only a short term immunity (measured in days to weeks), and lgG may confer a longer immunity if lgM are also present (measured in months or years).

That is mistaken, both immunoglobulins can be protective as long as they are present, IgM is produced for short times, IgG is more long lasting, but people with only levels of IgG can be immune even long after IgM disappeared.

These are two separate tests. But again, we do not know if any immunity is conferred at all, but some may be likely if both are present.

Or only one, or even if none are present, adaptive immunity is not 100% dependent on antibodies, and for some viruses perfect protection is achieved even without any immunoglobulins.

This is such elementary biology that I'm shocked to read the quote above

Putting aside that your knowledge is flawed the real problem is that you have assumed too much from the quote, statistically it is very important to know how many people have been exposed to the infection and how many developed symptoms, this information can only be reached by analyzing the antibodies (since the virus is not longer present), the protection conferred by those antibodies is a completely different matter.

One more fact is that there is no evidence that corona viruses are seasonal. Influenza is not a corona virus

This is also irrelevant for the purpose of the testing, It can be or not seasonal and still the information is necessary.

In reality is would be a completely different situation if 90% of the people positive in the tests had symptoms than if less than 1%, After getting this data next will be necessary to assess neutralization with those antibodies and take several samples over weeks and months from the same convalescent people to see how the levels change.

Saying that testing is not useful because we still don't know much about the disease immunity is nonsense, precisely because testing is one of the things that need to be done to understand it better.

The probability is that mass testing will show that a mage portion of the population was infected but with little affect. Why did Japan not see a spike in deaths? There was no change in the death rate from from all cause from past years (actually a slight decrease). So what did Japan do differently from other developed countries? Well nothing, it is becoming clear the whole western model and WHO model were flawed. The WHO model/predictions were based on everyone/every place being equal (population health, hygiene, etc..) the western predictions are based on a model of the health, hygiene if the west. But as info comes out the risk factors for developed countries are flawed because of political correctness, a single factor is common in over 70% of all serious illnesses this based on 3 UK studies and that is obesity/overweight most of the other medical factors are the result of being obese. 70% of the UK, USA, Canada, etc.. are seriously overweight with over 30% being obese. In Japan that is 5% heart disease is not a major factor in Japan so healthy active elderly and generally highly healthy population. The average North American over 45 in taking 4 to 5 daily prescription meds. Yes the test will show a very large number in Japan had covid and that will maybe make people in the west ask why Japan did not see mass deaths. Note that Japan's ICUs were full that is true but at 126 million Japan had fewer ICU beds than Canada at 37 million because it rarely needed them other than post operation and a few other cases as opposed to western countries where ICUs are filled with coronary disease related sick.

I didn't say testing was not useful. I specifically talked about the assumption that antibody presence confers (inferred) immunity. There is not enough information to state unequivocally that antibody presence confers immunity to everyone. Even the small study linked above found that not all recovered patients developed adaptive immunity. If you know why this is, please explain.

Local authorities will conduct the tests and send blood samples to the central government for analysis. The state will leave it up to the municipalities whether to inform the examinees of the results.

Surely the benefit of having blood drawn would be to reassure the patient as to whether contagion has occurred or

However, the government certainly does not see it that way, it seems...

Im so happy that the Japanese Government knows what they are doing! Because the rest of us have other views and opinions but the Japanese Government is doing things the best way I guess! Sometimes I feel that we are all living in Disney and life is so happy because decisions are being made by the J Government that are true and honest. Life is good.

I didn't say testing was not useful. I specifically talked about the assumption that antibody presence confers (inferred) immunity. There is not enough information to state unequivocally that antibody presence confers immunity to everyone. Even the small study linked above found that not all recovered patients developed adaptive immunity. If you know why this is, please explain.

That is an assumption not made in the article, which talks about testing for immunoglobulins and not about neutralizing antibodies, which are a very different thing.

In reality the test is for reactive antibodies, so they are looking for evidence of exposure, and no, the study is not concluding that some patients did not develop adaptive immunity, only that they did not detected it, which can have many different explanations, from very low levels being enough to protect the people to immunity based on other mechanisms different from antibody.

The patients recovered, that is proof they developed immunity (without it there is no recovery possible) to be able to correctly measure it first it is necessary to understand it well, which is not possible at this stage.

Forced selection ?

according to the article it says :

The blood tests, which look for specific proteins made by the immune system in response to infection, will be conducted on roughly 3,000 adults randomly selected in each of the three regions who consent to take part.

So what about the other 7,000 ?

Or are we now talking about the annual Medical Health checkup finally acknowledged as being used for... other purposes ? An acknowledgement from the Government, that they've been using our (well your) blood tests for other purposes all along?

So what about the other 7,000 ?

will be conducted on roughly 3,000 adults randomly selected in each of the three regions who consent to take part