After the first outbreak of the COVID-19 pandemic, Morocco launched a comprehensive vaccination campaign against the SARS-CoV-2 virus, to immunize the Moroccan population and reduce transmission of the virus. A recent study carried out by Moroccan scientists examined the effectiveness of its vaccination program, identifying the humoral response (i.e., the level of adaptive immunity) associated with several COVID-19 vaccines delivered in the kingdom, specifically in the Casablanca-Settat-Region.
The study was published last Wednesday, in the British scientific journal Nature.
The results found that a whopping 96% of vaccinated individuals in the sample showed signs indicating an effective immune response against the virus.
Entitled “Seroepidemiological assessment of SARS-CoV-2 vaccine responsiveness and associated factors in the vaccinated community of the Casablanca-Settat Region, Morocco,” the study revealed differences in seroprevalence rates, i.e., the number of persons in a population who test positive for a specific disease, among individuals vaccinated with different COVID-19 vaccines.
While the scientists found that all examined vaccines demonstrated effectiveness, the BNT162b2 vaccine also called Pfizer-BioNTech, commonly known as the Pfizer vaccine, demonstrated a particularly intense immune response.
Pfizer had a notably higher seroconversion rate than the other three vaccines that had been used in Morocco. Seroconversion, meaning the period over which antibodies develop, measures the transition from the moment of viral infection to when antibodies to the virus are present in the blood.
The research study also confirmed the impact of various demographic factors on antibody levels. Participants over the age of 65, for example, those with co-morbid chronic diseases, and women all showed an increased humoral response, indicating that these groups are most likely to have received an enhanced level of immunity.
The authors of the study highlighted its significance as the first of its kind in the region to evaluate the post-vaccination levels of immunity against SARS-CoV-2 generated by the four main types of vaccines implemented by the Ministry of Health in Morocco.
The study included 10,669 participants, aged 14 and older, in 16 provinces in the Casablanca-Settat region, who received various vaccines during the period of February to June, 2022.