Outbreaks with a novel coronavirus disease COVID-19 is caused by the SARS-CoV-2 virus. The virus has shown to be very contagious and has caused a worldwide pandemic in the Spring of 2020. The SARS-CoV-2 (COVID-19) virus is a single strand RNA virus with glycoprotein spikes on its surface. The spike protein (S) contains the receptor-binding domain (RBD) which has affinity to the angiotensin-converting enzyme 2 (ACE2). The interaction between RBD and ACE2 mediates the fusion of the viral and cellular membranes starting the infection process. The S protein has two subunits, S1 and S2. S1 contains the RBD region and the S2 is associated with the membrane of the virus. The nucleoprotein (N) is an abundant protein associated with virus structure and replication. ELISA assays have been developed using the S proteins and nucleoprotein of SARS-CoV-2 to detect antibodies to SARS-CoV-2.