June 27 Good Science News #18. Vaccination: What have we learned?
Updated: Jul 8, 2021
According to a recent article published in the international journal, Nature, on December 8, 2020, a 90 year old British woman received the first Covid-19 vaccine shot. Since that time, over 1.7 billion shots have been administered.
So what is the take home message from vaccination?
First of all, vaccinations work. Israel, for example, has seen the vaccine prevent Covid-19 infection in patients over 70 years of age about 95% of the time. A study from the UK showed a lower rate of protection, 80%, which is still a pretty good rate of return. For children, clinical trials involving the Pfizer or Moderna vaccines prevention rates were greater than 90% in both cases.
The Covid-19 virus continues to evolve and churn out new variants even as we get vaccinated against it.
Here is more good news.
Where it has been tested, the Pfizer vaccine appears to remain effective against virus variants, as vaccinated individuals were 75% less likely to develop Covid-19 from infection with the variant B.1.351, and almost completely protected from developing a serious illness. Unfortunately, the Oxford-AstraZeneca vaccine did not fare as well, particularly in Africa with the B.1.351 variant of Covid-19 is dominant.
Some questions remain to be answered. For one, it has been suggested that boosters will have to be given to keep the virus and its variants in check, but the first round of vaccinations was given too recently to be certain that this is the case. In addition, it is currently unclear how infectious vaccinated people will be, should they contract the virus and not express any adverse side effects. It is unclear whether or not these individuals will be able to transfer the virus to other, non-vaccinated individuals.
Then there is the question of side effects, the most notable being the blood clots that occur in some individuals that are vaccinated with the Oxford-AstraZeneca and the Johnson & Johnson vaccines. While these blood clots are serious and can be fatal, the risk posed by COVID-19 is greater than the risk of these side effects. It remains prudent to take the vaccine even with the small possibility of side effects.
The shining light is that fact that the use of the vaccine has saved over 13,000 individuals in the United Kingdom alone.
The situation is less rosy when one looks at countries that are less affluent. In fact, the recent surge in of Covid-19 cases and deaths in India was due to low vaccination rates, highly aggressive virus variants and widespread social interaction.
We are not out of the woods yet, and herd immunity, the point when enough immunity exists in the human population that the spread of the disease stalls, is at least a year away if not further.
The good news though is that the vaccines work and that, even though we need to maintain a constant vigil, it does appear to be the beginning of the end of the pandemic.