None of the COVID-19 vaccines currently being used for immunisation offer sterilising immunity, which completely prevents infection. Administering a booster dose will surely increase the level of neutralising antibodies but even that does not guarantee full protection from infection. Nearly a year after India rolled out the COVID-19 vaccination programme, administering a ‘precaution dose’, scientifically … Continue reading Booster doses only mitigate disease severity, do not fully prevent infection
Booster shots
Are there clinical trial data to support a homologous vaccine booster?
While data from a homologous booster clinical trial has now become available for Covaxin, there is no supporting data from India for Covishield. Yet, Covishield makes for up to 90% of vaccines administered to adults so far in India. On January 5, five days before the roll-out of the ‘protection dose’, scientifically called a third … Continue reading Are there clinical trial data to support a homologous vaccine booster?
India widens the vaccine safety net by immunising teenagers above 15 years
Covaxin was found to be safe and immunogenic in teenagers during a phase-2/3 clinical trial; only 175 adolescents aged 12 to 18 years were studied. The data of the trial, which is yet to be peer-reviewed, were posted on a preprint server on December 29. Nearly a year after the rollout of COVID-19 vaccines for … Continue reading India widens the vaccine safety net by immunising teenagers above 15 years
The basis on which India approves precaution dose remains unclear
On November 22, 2021, Dr. Balram Bhargava said there is no scientific evidence so far to support the need for a booster vaccine dose against COVID-19. The priority was on administering the second dose to all adults. No new evidence from India has become available to support an additional dose after Dr. Bhargava's assertion. There … Continue reading The basis on which India approves precaution dose remains unclear
How the idea of vaccine protection changed in one year
As the virus evolved, our perception of protection conferred by vaccines changed dramatically. From the popular notions of herd immunity and vaccinating our way out of the pandemic, the discussion is now centred around booster doses and the eventuality of living with the virus. As the virus evolved, our perception of protection conferred by vaccines … Continue reading How the idea of vaccine protection changed in one year
Does the Omicron variant make a case for booster doses?
What is the major objective of a booster dose -- to protect from infection or protect from severe disease and death, who should get it first whenever it is approved, is there enough evidence recommending for their use, and should we give boosters when primary immunisation is not complete? Dr. Chandrakant Lahariya, physician epidemiologist and … Continue reading Does the Omicron variant make a case for booster doses?
Groping in the dark on booster doses
Though over 1.26 billion doses have been administered as on December 4 with nearly 85% receiving one dose but only over 50% being fully vaccinated. Over 8% of health-care workers, 30% of those above 60 years and over 33% of people aged 45-59 years are yet to be fully vaccinated. And there is no scientific … Continue reading Groping in the dark on booster doses
Virus rages in Europe as epicentre shifts
While most of the new daily cases reported are among the unvaccinated, breakthrough infections and hospitalisations are being reported in the fully vaccinated too. However, the deaths have predominantly been among the unvaccinated. With the staggering increase in the number of daily fresh coronavirus cases and deaths in many countries in Europe, the continent has … Continue reading Virus rages in Europe as epicentre shifts
‘Pandemic far from over’ even as global death toll crosses five million
The global death toll from COVID-19 crossed five million on November 1 and yet the the global number of reported cases and deaths from COVID-19 is now increasing for the first time in two months. The first million deaths were recorded on September 8, 2020, nearly nine months after the first death occurred, while the two-million mark was breached three and a … Continue reading ‘Pandemic far from over’ even as global death toll crosses five million
mRNA vaccine manufacturers loathe to share know-how
Moderna, which was funded $1 billion for research by the U.S. government, said in October 2020 that it will not enforce COVID-19-related patents against those making vaccines intended to combat the pandemic. But the company has refused to transfer technology to the South African hub to manufacture its mRNA vaccines for distribution to the African … Continue reading mRNA vaccine manufacturers loathe to share know-how