Vaccine mix
Ever since the worldwide devastation caused by the COVID-19 pandemic, the heterologous prime-boost concept of vaccination has been in the purview of scientific research, discussion and debates. Preliminary small clinical trials using a mixed regimen of Pfizer –BioNTech and Oxford-AstraZeneca vaccines in the U.K. (Com-COV), Spain (CombivacS), and Germany (Charite and Saarland studies), have all shown a boost to the immune response,with none or minor side effects, when compared to those who got both jabs of the same vaccine (Page 1, “Covishield-Covaxin mix gives better protection, says ICMR”, August 9). Safety, reactogenicity, efficacy and immunogenicity of these combinations are the fundamentals for their use on a large scale. Until long-term follow-up studies are conducted and the data peer-reviewed and substantiated, the use of such combinations of vaccines remains in the realms of speculation. The results of the study in the Philippines, combining the inactivated vaccine CoronaVac, with six other approved vaccines, and the CMC Vellore mixed vaccine trial of Covaxin and Covishield will shed more light on the mix-and-match benefits of COVID vaccines.
Dr. Biju C. Mathew,
Thiruvananthapuram
Vaccine trial volunteers
I would like to draw attention to the challenges being faced by a particular group, namely, the volunteers of the Covishield vaccine trial of 2020.
I am a doctor, 64, and volunteered at my alma mater, KEM hospital, Parel, Mumbai, for the ICMR/Serum Institute sponsored phase 2/3 double blind CoviShield vaccine safety and effectivity trial. I received my two doses in September and October 2020. On my request in early 2021, the randomisation was unblinded, and I was informed in February 2021 that I had received the vaccine and not the placebo.
We, vaccine trial volunteers, face the following challenges: the ICMR/Serum Institute have not yet issued us a proper vaccination certificate.
The KEM authorities have issued us a letter, which may not be valid nationally or internationally for our travel. We vaccinated volunteers do not appear as COVID-19 vaccinated on the Co-WIN App or government records, linked to our Aadhaar number. New variants of the virus have since been detected and we are exposed to them constantly, during the course of our work. A year has passed since our vaccination and despite reminders, there have been no efforts made by the ICMR/Serum Institute to check our antibody levels or guide us regarding a booster dose of the vaccine.
We volunteered in good faith, to be of help to others in this pandemic, especially at a time when all sorts of negative messages were floating around. I urge the ICMR/Serum Institute/Government to understand our challenges and evolve appropriate measures.
Dr. Suresh Sundar,
Mumbai
Game changer
The Olympics gold medal in javelin by Neeraj Chopra is a game changer and is sure to inspire a new generation of Indians, who could then go on to dominate in the international sporting arena. I am confident many youngsters will now be interested in javelin throwing as well as the other track and field events such as hammer throw, discus and shot put. Cricket may have some competition now. There could be a quantum jump from the spade work done by earlier stalwarts.
A.V. Narayanan,
Tiruchi, Tamil Nadu
