The All India Institute of Medical Science (AIIMS), New Delhi, has conducted a study on individuals who tested Covid-19 positive after vaccination and revealed that there was no fatality. The study was conducted during April-May when the second wave of the pandemic was at its peak.
Out of the 63 individuals — 41 male, 22 female —enrolled in the study, 10 individuals were administered Covishield, while 53 received Covaxin. 36 people were administered two doses, and 27 individuals received at least one dose of either Covid-19 vaccine. The patients were aged between 21 and 92 and had no comorbidities.
Viral load, the measure of the total number of viral particles in a particular volume of fluid, was high at the time of diagnosis even in vaccinated patients and they also reported high temperature persisting for 5-7 days, similar to symptoms of unvaccinated patients.
“Viral load at the time of diagnosis was high in all the patients irrespective of vaccination status or type of vaccine received and the initial course of disease with high-grade non-remitting fever lasted for five to seven days in the vaccinated group, similar to the clinical presentation in unvaccinated patients,” the report said.
The study found that in case of breakthrough infection, which is when someone contracts Covid-19 in spite of being fully or partly vaccinated, the Covid-variants of B.1.617.2 and B.1.1.7 were the two variants of concern.
“While antibody levels for a subset of patients were available, they became infected nevertheless and presented to the emergency just like other patients, putting in doubt the protection offered and or clinical relevance of total immunoglobulin G (IgG) as a surrogate of COVID-19 immunity,” the report added.
Cases of infection in vaccinated individuals have also been reported in the US. The US Centers for Disease Control and Prevention (CDC) said that a total of 9,000 individuals had been infected after being vaccinated at the end of April.