FAQs about Covid-19 vaccines

How long does the vaccine “last”?

It is too early to tell as the vaccines have become available only within the past year or so.

Recent evidence is that the J&J vaccine has a persistent robust immune response (antibodies and cellular immunity) for at least eight months. It is also more effective against the Delta variant (which is now becoming the dominant variant in SA) than its effectiveness against the Beta variant. The J&J immune response has been increasing over the study period of eight months.

For Pfizer, at least six months based on the length of time it has been studied, maybe two-three years, based on other similar vaccines.

Concern about blood clots and inflammation of the heart (myocarditis)

Very rare cases of unusual types of thrombosis associated with thrombocytopenia (low platelet count) have been reported following vaccination with the J&J vaccine and the Astra Zeneca vaccine.

In the USA, 15 cases in approximately eight million individuals were vaccinated.

The Pfizer vaccine has not been associated with the blood clot condition.

A blood clot that develops after vaccination is called a vaccine-induced thrombosis. The most serious of these clots tend to occur in large veins in the brain and abdomen while the platelets (that would normally be part of the clotting process) drop dangerously low as well. This is called vaccine-induced thrombotic thrombocytopenia. It is an extremely rare condition, but local experts and treatments are available.

The chances of developing this condition are extremely rare and the South African Health Products Regulatory Authority confirmed that no major safety concerns were identified in the healthcare workers who partook in the Sisonke vaccine trial.

To put this into perspective, the risk of a blood clot in someone who has active Covid-19 infection is about 4.5-20 per 100 000 cases. Whereas with the vaccine it is approximately 0.08 per 100 000 vaccines, which is significantly less.

A previous history of blood clotting is not a contraindication to vaccination. You should continue your routine medication on the day of vaccination. If you have any concerns, consult your treating clinician.

With the Pfizer vaccine, there have been reports of inflammation of the heart in 12 to 39 years old. Most reported cases have occurred in men within a week of vaccination, more commonly after the second dose. The vast majority of cases were mild and responded well to medical treatment with rapid symptom improvement. The benefits of the mRNA vaccines outweigh this potential risk.

Based on analysis of data from an active surveillance system in the United States, the estimated rate of myocarditis/pericarditis among individuals 12 to 39 years old following the second dose of an mRNA vaccine was 12.6 to 32 cases per million.

Symptoms after taking the vaccine

Common symptoms after vaccination include pain, swelling and redness on the injection site, mild fever, headache, tiredness and other flu-like symptoms. These symptoms usually last one to two days, at most a week. Most of these side effects are caused by the desired immune response in the body.

Contact your doctor or healthcare provider if:

• The redness or tenderness at the injection site worsens after 24 hours

• The side-effects are worrying and have not cleared after a few days

Any side effects that occur more than 24-42 hours after you have had your vaccine need to be reported via the MedSafety app

An individual can report via the app themselves or get their healthcare practitioner to report on their behalf.
The vaccine was created so quickly. Was it tested sufficiently? There is suspicion that there may be issues with the vaccine.

Before Covid-19 vaccines can be administrated:

• The vaccine must be proven safe and effective in large clinical trials.

• A series of independent clinical reviews of the efficacy and safety of the vaccine is required.

• This evidence must also be reviewed for policy recommendations on how the vaccine should be used.

• An external panel of experts convened by the WHO called the Strategic Advisory Group of Experts on immunisation analysed the results from clinical trials.

• The panel then recommends whether and how the vaccines should be used.

• Officials in individual countries decide whether to approve the vaccine for national use and develop policies for how to use it in their country based on the WHO recommendations.

What was the process in developing the vaccine and was it hurried?

The development of these vaccines started long before 2020. SARS-CoV-2 is a member of the coronavirus family of viruses. These viruses have been known to cause diseases in humans and animals for many years.

Following the outbreaks of SARS in 2002 and MERS in 2017/2018 (both caused by coronaviruses), scientists had already started work on vaccines that could be effective against these pathogens. The vaccines being tested now are an extension of this research.

One of the greatest limitations on vaccine development is funding. This time, the whole world has had an interest in developing a vaccine, leading to the funding of this very important work.

Companies have seen the value in investing, alongside philanthropists who have also been willing to contribute, as well as many countries having pooled their resources to fast-track the development of these vaccines. This has made the process much faster than usual.

Usually, a lot of scientific development is private and shared in scientific journal publications that are not accessible to everybody. Something truly remarkable about this pandemic is the way so much research has been published “open source”, where anyone who desires can access it.

The publishing of the genetic code for the SARS-CoV-2 virus spike protein on January 11, 2020, was a huge milestone and making it available to all researchers helped to get the process moving faster.

All the vaccines that have been approved for use have followed the three required trial stages: phase one (safety/dosage), phase two (human safety) and phase three (human efficacy).

The vaccines were trialled on more patients than most previously approved vaccines. They have been shown to effectively prevent a large percentage of those who received them from developing severe Covid-19 or dying from it.

The side effects experienced by patients in the clinical trials were very mild. As the vaccines are rolled out to the public, they will move into the next phase of surveillance, where their effectiveness and any new, rarer side effects will be observed, reported and monitored.

Can the Covid-19 vaccine cause infertility?

No.

What percentage of people does the company want to be vaccinated?

Everybody except those who for specific medical reasons should not be vaccinated, so effectively 99%.

How does herd immunity work?

When a lot of people in a community are vaccinated, the virus cannot circulate easily, because most of the people it encounters are immune. If most people are vaccinated, those who are not protected by vaccines are less likely to contract or be exposed to the harmful virus. This is called herd immunity.

No single vaccine provides 100% protection, and herd immunity does not provide full protection to those who cannot safely be vaccinated. But, with herd immunity, these people will have substantial protection, thanks to those around them being vaccinated. Vaccinating not only protects you but also protects those in the community who are unable to be vaccinated.

Why are Covid-vaccinated persons still getting Covid?

No vaccine is 100% effective.

There are two ‘scenarios’ when a person could get Covid-19 after receiving a vaccine.

A person may have been exposed to Covid-19 within 10-14 days before receiving the vaccine. When the vaccine is given, they are in the ‘incubation period’ (similar to a ‘window’ period). At the time that the vaccine is given, the person does not have symptoms, but symptoms such as cough, fever, headache and body aches and pains develop within 7-10 days of receiving the vaccine.

If Covid-like symptoms occur, and persist during the 7-10 days after getting the vaccine, a person should see a medical practitioner immediately.

A person may develop a ‘breakthrough infection’ at any time (weeks, months or years) after the vaccine. The vaccine trials have shown us that there are ‘breakthrough’ infections after all types of vaccinations against SARS-CoV-2.

But breakthrough infections occur much less frequently in persons who have been vaccinated, (10 times less) and that these infections are usually mild-moderate and don’t require admission.

Feeling of uneasiness that one person is vaccinated and not their loved ones.

Understandably, one wants their entire family to be protected. However, the limited supply of vaccines means that their use must be prioritised. The government prioritised the health sector and the most vulnerable (over 60 yrs).

To protect the healthcare workforce, healthcare workers were made the first priority to keep them available to treat patients. The decision was made to vaccinate according to age brackets (starting with over 60s and moving downwards) because the Covid-19 data in South Africa has shown that age was the biggest risk factor for severe disease.

Every person who is vaccinated reduces spread to other people, especially their family members. With the highly transmissible Delta variant, many households are becoming infected so it is crucial that every person gets their vaccine as soon as they are eligible to reduce the spread within the household.

How does getting the vaccine create a safer work environment?

It is correct that people who are vaccinated can still pass on the virus if they become infected. That is why the measures of masking, frequent hand-washing and social distancing remain as important as ever. However, people who are vaccinated and get infected do not spread the virus as much as people who are not vaccinated. This makes our homes and the workplace safer.

Is there a choice on which vaccine we will get?

There is not a choice as to which vaccine to get. We have to use what is available at the time and get vaccinated as soon as possible. At present, we only have the two-dose Pfizer vaccine available. As of the middle of July, we have no line of sight of the J&J vaccine pipeline. Although Sinovac has received conditional approval for use in SA, it is not known when supplies will arrive.

Short- and long-term effects of vaccination

The vaccines take a few weeks to become effective. After about 14 days, there is some protection, which increases over time. In the two-dose vaccines (like Pfizer) one is considered fully vaccinated two weeks after the second dose.

After a few months’ immunity begins to wane, booster doses are likely to become necessary if the SARS-CoV-2 continues to mutate to new variants as it has been doing. This is similar to influenza.

Long term, the immune system will have a “memory” to react to the virus as soon as the body encounters it again and responds to neutralise the virus; how long the memory will last is not yet known – too early to tell.

Does the vaccine affect pregnancy?

Like all medicines, we are careful not to give them in the early stages of pregnancy while the baby is developing. Therefore, vaccination should not be given within the first 14 weeks of pregnancy.

Based on what we know about these vaccines, there is no specific reason to believe there will be risks that would outweigh the benefits of vaccination for pregnant women. While pregnancy puts women at higher risk of severe Covid-19, very little data are available to assess vaccine safety in pregnancy.

For this reason, it is advised that vaccines are offered to all pregnant and breastfeeding women who are eligible (e.g. healthcare workers) and who have completed 14 weeks of gestation.

It is not yet clear whether Covid-19 vaccines can be excreted through breastfeeding. To determine the best course of action, the developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for vaccination against Covid-19. The WHO does not recommend discontinuing breastfeeding after vaccination.

How long do you have to wait if you were Covid-positive to take the jab?

You must wait a minimum of 30 days after recovery from Covid-19 before being vaccinated. If you have had a first Pfizer vaccine and then become Covid-19 positive you must wait for 30 days after you have recovered from that infection for your second dose.

How can I safely receive the Covid-19 vaccine if I had allergic reactions to other vaccines?

A person who has had a severe allergic reaction to the first dose of an mRNA vaccine (such as. Pfizer) should not have a second dose. A person who has a known allergy to a component of the Covid-19 vaccine should not receive the vaccine.

There are no other medical reasons (‘contra-indications’) why a person should not take a Covid-19 vaccine.

All vaccines contain additional substances to stabilise and preserve the vaccine proteins, RNA or fatty acids. Persons who have allergic reactions to these substances or the vaccine material may develop allergic responses.

Therefore, a person who has experienced allergic reactions to any kind of vaccine in the past should inform the vaccinator when receiving a Covid-19 vaccine. If a person has a mild allergic reaction to the first dose of an mRNA vaccine (such as. Pfizer), they may still receive the second dose, but they should inform the vaccinator.

Allergic reactions to any kind of medicine are usually ‘specific’ to that kind of medicine. In other words, an allergy to one kind of medicine does not mean that a person will be allergic to all medicines, or all vaccines. So, if a person is allergic to penicillin, for example, they can still receive a Covid-19 vaccine without fear of an allergic reaction.

Mild allergic reactions to Covid-19 vaccines, for example, itchiness at the injection site happen to one in 1000 people. If this symptom continues, it can be treated with a cream such as a topical prednisone.

Mild allergic reactions may be more common after the second mRNA vaccine. Stress-related reactions to vaccines are not uncommon and include fainting or hyperventilation immediately after the vaccine. These reactions may be managed by resting and giving sugar water or tea.

The most severe allergic reaction to any vaccine is called ‘anaphylaxis’.

This is extremely rare. Preliminary data for the Pfizer vaccine suggests that anaphylaxis may occur at a rate of 11 cases per million doses. If anaphylaxis occurs it will happen within 30 minutes after vaccination.

Anaphylaxis leads to low blood pressure, dizziness, difficulty breathing and collapse, with or without a skin rash. Anaphylaxis requires immediate treatment including resuscitation with fluid, adrenaline and steroids, and may require treatment in an intensive-care unit.

All vaccination centres have equipment and protocols on-site to deal with this reaction.

Are mRNA vaccines safe?

The Covid-19 mRNA vaccine technology has been rigorously assessed for safety and clinical trials have shown that mRNA vaccines provide a long-lasting immune response.

mRNA vaccine technology has been studied for several decades, including for Zika, rabies and influenza vaccines. mRNA vaccines are not live virus vaccines and do not interfere with human DNA.

The mRNA in the vaccine teaches your cells how to make copies of the spike protein. If you are exposed to the real virus later, your body will recognise it and know how to fight it off. After the mRNA delivers the message to make the proteins, the body degrades the mRNA.

Can my children be vaccinated?

Children are not eligible for vaccination at this stage in South Africa. Most of the vaccines have been tested and approved for adult use, with some now being approved for use in children over 12 years in other parts of the world.