1. Covid antibody test are for academic interest (research use) Doctors do not make any decisions based on antibody tests as the co-relation of antibody levels to immunity levels is yet to be established. 2. IgM tells about recent infection. Ig G about old ( more than 3 - 6 months) infection. 3. As it does not help in decision making, we do not advice antibody tests. They are only done at present for people who say they had symptoms of covid in the past, but never tested with rtpcr. 4 . Antibodies are present in the body forever after infection ( immune -memory). They are proteins. Depending upon the nutrition of the body,the level of these proteins change. If patient has poor nutrition then the titre( significant quantity)of antibodies won't be adequate. Since, the internal adequacy of antibodies, is variable,we can get covid again. If we have good nutrition, high protein (antibodies) will be protective and this second infection would be a mild disease.

After about a month , you can check for IgG levels - which is the long term antibody that may be seen. It’s a cheap test in most places, but at this time it is only of academic interest. We do not make any medical decisions based on it. Normally it’s reported to be present for about 6 months after infection. Reinfection is less likely for the next 3-6 months. But there are several factors such as antibody titre levels and presence of neutralising antibodies that many labs may not be able to detect. The presence / absence of anotbody is not always certain. If you have had Covid - been diagnosed and recovered ; regardless of antibody levels - it is less likely you will get it in the next 3-6 months