The goal of the coronavirus vaccine is to slow the spread of COVID-19 so that we can all get back to everyday life. However, to stop transmission of the disease and establish herd immunity, 60-70% of us must be immune.
The vaccines promise not only to protect people from infection but also to prevent those infected from becoming extremely ill. Still, there are some remaining questions that will take time to answer.
The Coronavirus Vaccine Pipeline
The coronavirus vaccine aims to stimulate a protective immune response in the body that will prevent or reduce infection from the SARS-CoV-2 virus. Vaccines for the flu, measles, mumps, rubella, tetanus, and polio include the dead virus, viral proteins, or live-attenuated or weakened viruses that don’t cause infections. But the Coronavirus vaccine that is furthest along with consist of RNA or DNA, and that’s new.
The companies Pfizer/BioNTech and Moderna vaccines use a technology not previously approved for humans. Both consist of coronavirus genetic material, called mRNA which enters a person’s cells and produces copies of a SARS-CoV-2 viral protein. These proteins stimulate the immune system and prepare it to attack if you encounter the infectious virus.
Whatever the strategy, the step just before a vaccine becomes generally available is a phase III trial, which tests its efficacy in thousands of volunteers. Right now, there are 13 vaccines in such clinical trials, which you can follow at The New York Times vaccine tracker site.
Promising Interim Results
So far, several companies have reported promising interim results, with Pfizer/BioNTech and Moderna announcing that two doses of their RNA vaccines given 3-4 weeks apart are over 90% effective at preventing COVID-19.
AstraZeneca, together with Oxford University, took a different strategy, using a modified non-infectious cold virus that carries a coronavirus protein that stimulates an immune response and has been 70% effective in a combined phase 2 and 3 trial. Similarly, Johnson & Johnson have developed a modified human cold virus with promising results.
Due to the urgency of the pandemic, regulators are making rapid decisions about authorizing emergency use of the vaccines based on the interim results – lightning speed. compared to the normal two-year minimum to test a vaccine.
Efficacy and Effectiveness
There are two measures of a new vaccine: “Efficacy” measures how well a vaccine prevents disease in a clinical trial, and “effectiveness” how it works in the population as a whole. Generally, Phase III trials include healthy volunteers without serious health conditions and exclude children, the elderly and pregnant and breastfeeding women. Also, studies may not adequately represent racial and ethnic differences. In other words, a Phase III trial does not reflect the public at large.
It’s also possible that a vaccine is only effective in multiple doses or when combined with an adjuvant, i.e. an additive that boosts the immune system. For each vaccine, this additional clarity will take time.
So far, there are no serious side effects. The vaccines may induce fever, chills, fatigue, muscle aches, and headaches and seem to be worse than the flu vaccine. There were reports of one death and one participant with a severe neurological problem, but both appeared to be unrelated to the vaccine.
Availability will depend on the process in each country for approval without the final Phase III trial data and peer-review. After that comes production capacity and the public health vaccination strategy, which will likely prioritize the most vulnerable populations – in most countries, this means health care workers, older care home residents and staff and people over a set age – either 60, 70, or 80.
The More the Better
There is no doubt that the more people who get vaccinated against COVID-19, the better it is for everyone.
Most adults should do so both to protect themselves and our society as a whole. A vaccine combined with hygiene measures – mask-wearing, social distancing, handwashing and isolation after contact or a positive test result – will allow us to open up all businesses, schools, and public venues.
Vaccinations may become mandatory in certain situations, in your workplace if you’re a health care worker or staff at an elder residence, or if you’re travelling. In recent news, Qantas stated that only COVID-19 vaccinated passengers would be allowed to fly.
And if you’re in a high-risk group, it could save your life.
And If You’ve Had COVID-19?
We don’t know the answer to that yet. The phase III trials didn’t test previously infected people, and it’s not clear who has protective immunity, either after natural infection or after having the vaccine. That means that you still need to wear a mask and take other safety precautions even after getting vaccinated or recovering from COVID-19.
Once we know whether the vaccine prevents infections or reduces the likelihood of SARS-CoV-2 infection from becoming COVID-19, we can figure out whether vaccines will stop the spread of the virus. Until then, we must continue to protect ourselves and others – despite vaccination – and keep improving the methods for diagnosing and treating COVID-19.
Understandably, you might want to wait before getting a vaccine because it’s too early to be sure that they are effective and safe. You might want to wait for a more traditional vaccine that we have more experience with.
The best advice is to keep up-to-date with the information on vaccines from the World Health Organization to make an informed decision.
Even with new vaccines on the way, as of today, the best way to stay safe is still social distancing, wearing a mask and washing your hands.