Human COVID-19 (SARS-CoV-2) IgA ELISA kit is designed for analysing quantitative concentrations of human IgA class antibodies directed against SARS-CoV-2 (COVID-19 IgA) present is samples of plasma (heparin and citrate) and serum. It allows the direct detection of the pathogen, where a positive results corresponds to a 98.26% specificity.


Coronavirus disease 19 (COVID-19) is a novel respiratory disease that is caused by the causative agent which is known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This belongs to family of coronaviruses, specifically to the genus Betacoronavirus and it is also closed related to SARS coronavirus (SARS-CoV). The human coronaviruses include: HKU1, NL63, OC43 and 229E, these are found to be widespread throughout the winter season. Over 80% of the adult population already contain antibodies against human coronaviruses, since they are responsible for one third of all acute respiratory diseases. The zoonotic reservoir of this virus is found to be from bats.

Coronaviruses are made up from many proteins which usually includes the spike, nucleocapsid, envelope and membrane. There is evidence to indicate that the spike protein has the ability to enter cells via a mechanism which is similar to the angiotensin converting enzyme 2 (ACE2). Some of the common respiratory symptoms of the infection include: fatigue, coughing, breathing difficulty, shortness of breath and fever. In more severe cases this can lead to pneumonia, kidney failure, SARS (severe acute respiratory syndrome) and death. Human to human transmission of SARS-CoV-2 is mainly through droplet infection either by sneezing, coughing or even close contact with patients that are infected. At present, there is no specific vaccine or treatment that is available against SARS-CoV-2 infection.


All reagents supplied need to be stored at 2 °C – 8 °C, unopened reagents will retain reactivity until expiration date. Do not use reagents beyond this date.

  • SARS-CoV-2 Antigens Coated Microtiter Strips (IgA).
  • Sample Dilution Buffer.
  • Stop Solution.
  • Washing Buffer (20x Conc.).
  • Enzyme Conjugate (IgA).
  • TMB Substrate Solution.
  • Negative Control.
  • Cut-Off Standard.
  • Positive Control.


The minimum detection sensitivity level of human IgA antibodies against SARS-CoV-2 (COVID-19-IgA) using this COVID-19 IgA ELISA kit was to a specific cut-off point and a positive result was indicated by a 98.26% specificity.




– Equivocal: 9 – 11 U
– Negative: < 9 U
– Cut-Off: 10 U
– Positive: > 11 U
– Diagnostic Specificity: 98.26 %
– Cross Reactivity: No significant evidence of false-positive results due to cross-reactions. However, cross reactions with antibodies to influenza virus and adenovirus cannot be excluded.


  1. Distinct features of SARS-CoV-2-specific IgAresponse in COVID-19patients. Eur Respir J. (2020) 56 (2): 2001526. Yu H.Q., et al.
  2. A cross-reactive human IgA monoclonal antibody blocks SARS-CoV-2 spike-ACE2 interaction. Nat Commun. (2020) 11 (1): 4198. Ejemel M., et al.
  3. The role of IgA in COVID-19. Brain Behav Immun. (2020) 87:182-183. Chao Y.X., et al.
  4. IgA-Ab response to spike glycoprotein of SARS-CoV-2 in patients with COVID-19: A longitudinal study. Clin Chim Acta. (2020) 507:164-166. Padoan A., et al.


  • Full Name: COVID-19 (SARS-CoV-2) IgA ELISA Kit
  • Reactivity: Human
  • Sample Type: Serum, Plasma
  • Sensitivity: Cut-Off Point



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