Covid-19 vaccines have hit SA: We answer three FAQs about the jabs
Will we need two doses? What are the side-effects? We answer these questions and more
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Image: Alaister Russell/The Sunday Times
In the words of President Cyril Ramaphosa, the arrival of the first batch of Covid-19 vaccines on SA soil marked “a major milestone in our fight against the coronavirus pandemic”.
One million doses of the AstraZeneca vaccine produced by the Serum Institute of India (SII) landed at OR Tambo International Airport in Johannesburg on Monday.
“This batch will benefit our health-care workers who have been at the forefront of keeping us all safe,” said Ramaphosa, alluding to the first phase of the country's vaccination rollout plan.
WATCH | First one million Covid-19 vaccinations hit SA shores.
As the possibility of getting a Covid-19 jab will soon become a reality for some, questions have been raised about how the vaccine works.
We asked researchers David Manheim, Merrick Pierson Smela and Ginny Schmit from 1DaySooner, an international non-profit organisation that advocates on behalf of Covid-19 trial volunteers, for answers.
AstraZeneca is a two-dose vaccine. Will all the vaccines we’ll be getting be two-dose vaccines? If so, why do we need two doses?
All approved vaccines (Moderna, Pfizer/BioNTech, Oxford/AstraZeneca, SinoVac, Sinopharm) are two-dose vaccines. Johnson & Johnson is developing a one-dose vaccine, but it has not yet finished clinical trials.
The reason most vaccines are given as two doses is because this leads to a stronger immune response. After the first dose, the body starts to produce some immune cells that recognise Sars-CoV-2. The second dose triggers these cells to proliferate and reinforces the immune response. Therefore, two doses provide improved protection compared to one dose.
Given the current limitations of supply, there have been proposals to vaccinate people using only one dose instead of two. This would have the advantage of vaccinating twice as many people.
However, this is controversial because it is unknown if the weaker immunity provided by one dose will last more than a few weeks.
What are some of the most common side-effects of the Covid-19 vaccines?
The US Centers for Disease Control and Prevention (CDC) provides a list of expected, common side-effects after receiving the Covid-19 vaccines. These side-effects are a result of your body’s immune response and are expected with just about all vaccines, whether for flu, shingles, Covid-19 or others.
These include pain or swelling at the site of the injection, and you may experience fever, chill, fatigue or headache for the a day or two after receiving a vaccine.
Will I have to wear a mask and social distance once I’ve had the vaccine?
It is not completely clear if the vaccine fully prevents infections or only eliminates symptoms, making it possible for people who were vaccinated to infect others.
Because the vaccine does not begin working immediately, people who were vaccinated should certainly wear masks at least until the vaccine is effective.
The timeline until this occurs is unclear, but seems likely to be at least two weeks.
It is also not completely clear if the vaccine fully prevents infections or only eliminates symptoms, making it possible for people who were vaccinated to infect others.
Above and beyond that, countries should generally not end mask mandates until the vast majority of people are vaccinated and the virus is nearly or completely eliminated.
• This article is adapted from one originally published on Sunday Times Daily. To read the full article, and for answers to more frequently asked questions about Covid-19 vaccines, click here.
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Just R20 for the first month. Support independent journalism by subscribing to our digital news package.