The study entitled "Covid-19: molecular and serological profile of Moroccan patients after clinical recovery", conducted between March 25 and April 9, 2020 by the Hassan II University and the Mohamed VI University of Health Sciences of Casablanca showed that typical antibody response is induced during the SARS-CoV-2 infection, while the serology testing provides important complementation to RNA test for pathogenic specific diagnosis and helpful information to evaluate the adapted immunity status of patient.

The study, which focused on the molecular and serological profile of patients admitted to Sheikh Khalifa International University Hospital in Casablanca, involved people discharged from hospital after completion of 10 days treatment, normalization of biological tests, clinical recovery and either two consecutive negative RT-PCR, or after 24 days of hospitalization.

The document revealed that 18% of the recruited patients were asymptomatic while the remaining 82% presented one or more of the following symptoms: fever, cough, dyspnea, myalgia, chest pain, headache, sore throat, diarrhea and/or vomiting.

According to the study, comparison between the serological and virological results showed that there is no correlation between the results of SARS-CoV-2 RT-PCR test after clinical recovery, and the detection of SARS-CoV-2 IgG and IgM antibodies.

This way, serological testing appears to be an interesting method that could be used to declare biological recovery for patients in whom the N gene persists in the RT-PCR, it added, saying that serological testing appears to be the most reliable diagnostic method in surveillance, comparing to RT-PCR because of its inability to detect past infection.