Thammasat invented a ‘Covid-19 Rapid Antibody Test IgG/IgM Prototype Kit’ to detect 'Covid-19 antibodies' in the blood, help screening for asymptomatic Covid-19 infections.

Monday 23 February 2022 

     Asst. Prof. Dr. Jeeraphong Thanongsaksrikul, Assistant Dean for Administration, Faculty of Allied Health Sciences, Thammasat University as head of the Laboratory of Molecular Diagnostics Center revealed that they have now developed “Covid-19 Rapid Antibody Test IgG/IgM Prototype Kit” under funding support from the National Research Council of Thailand (NRCT), which is expected to be fully developed within 1-2 years. The current cost is not over than 100 baht per kit.

     Covid-19 Rapid Antibody Test IgG/IgM Kit will support the work of RT-PCR and Antigen Test Kit (ATK), but the difference with the Covid-19 Rapid Antibody Test IgG/IgM Kit is that it is able to detect the Covid-19 asymptomatic infections.

     Asst. Prof. Dr. Jeeraphong added that the Covid-19 antibodies can only be found in those who have already been infected with Covid-19, both in those with and without symptoms, and will not be found in the components of the Covid-19 vaccine currently in use. For viral antibody testing, it is necessary to wait up to 3 to 7 days after infection in order for the immune system of the infected person to produce antibodies to a level that is high enough to be detectable, which is most effective in the second week of infection.

     “It must be understood that RT-PCR is a genetic test while ATK is used to detect viral proteins by which both of these methods are accurate in the first week of infection. The Covid-19 Rapid Antibody Test IgG/IgM Kit will be used to detect immunity which gave the second week accuracy. We then look forward to the future to use this test kit to track community infections. Especially as Covid-19 has become endemic and most of those who have received the Covid-19 vaccine, when infected, there will be very few or no symptoms. Today we tend to check only those who have symptoms, while for those without symptoms, we will not check. Therefore, in the future, random testing with ATK or RT-PCR may not be appropriate. We then designed this test kit to detect antibodies in the blood which is found only in those who are infected,” Asst. Prof. Dr. Jeeraphong said.

     Currently, the most popular antibody testing methods are ELISA and Lateral Flow Immunochromatography to detect immunity to the protein spike (S) or nucleocapsid (N) of COVID-19, which can be found through infection and by vaccination with the COVID-19 vaccine. Therefore, currently available antibody test kits cannot be used to differentiate immunity between infection and COVID-19 vaccine.

     Therefore led to a research project on “2019 novel coronavirus antigen selection and production of antibody immunoassay kit by studying the serological response of Covid-19 recovered individuals” that the Faculty of Allied Health Sciences, Thammasat University progress currently.