Do You Need The Booster Jab?

The USA, the UK and Israel are all already offering booster doses of COVID-19 vaccines. The FDA has recently allowed the use of a booster dose in certain populations, no matter which vaccine  you have taken previously. These additional vaccinations are important for continued protection against COVID-19 infection because immunity wanes with the passing of time.

South Africa only has 33.82% of the adult population fully vaccinated and 40.1% of adults partially vaccinated. The most vulnerable of us, the elderly over 60yrs, have not all vaccinated, and that remains a concern. It is more important to get our senior citizens vaccinated, than for the rest of us to get booster shots.  

Frequently asked question regarding Booster Vaccinations:

Many people are asking whether they need a booster dose, so here is an attempt to accurately answer the most common questions.

I Had My Two Pfizer Doses From June Onwards, Do I Need Another Dose Now?

  •  2 doses of Pfizer gives excellent protection against being infected and against severe illness for at least six months. Most people in SA will not be more than 6 months past their second dose until next year, and thus no boosters are available at this stage.
  • Remember that SA had 6 weeks (42 days) between first and second Pfizer doses – thus it is expected that immunity will be longer lasting, and it may be possible to delay the booster dose.
  • The timing of boosters, and which groups will be eligible (such as elderly patients or those with comorbidities) is still to be determined and is yet to be evaluated by SAHPRA and the Ministerial Advisory Committee.
  • At this point in time, there is no clarity on when boosters will be available following two Pfizer vaccines and whether the booster will be another Pfizer or a different vaccine.
  • For travel to countries that require booster doses, the two doses of Pfizer are valid if travel is within six months of the second dose, which it should still be for most South Africans.

I had one J&J vaccine from July onwards, do I need another dose?

  • No, not unless it is more than six months since you had your J&J jab.
  • From the Ensemble study, we know that J&J remains effective for at least 8 months. After this time immunity starts to wane and may require a boost.
  • At the moment, the booster J&J dose is only being offered to Healthcare workers who participated in the original SISONKE trial and received their first dose between February and May 2021.
  • Teachers, policemen and others who received J&J after the SISONKE trial are not yet eligible for boosters.

I had one J&J vaccine between February and May as part of Sisonke trial, do I need another dose?

  • Yes, it is now between 6 and 9 months after receiving your first J&J dose, and it is expected that your immunity is starting to wane.
  • A booster dose now will elevate antibodies as well as cellular immunity, giving much needed protection to Healthcare workers ahead of the expected 4th wave.


I had J&J as part of Sisonke, should I continue on the trial and get another J&J now, or should I rather wait to have a Pfizer?

Pros of having J&J now:

  •  As the Department of Health and SAHPRA have not yet approved booster doses, the only way of getting a booster at the moment, is by participating in the SISONKE trial.
  •  The 4th wave is anticipated from mid December and it would mean having enough time to mount a boosted immune response before this. This is especially relevant for healthcare workers in high risk settings, who received their first dose 6 to 8 months ago.
  • The booster J&J dose can be officially registered on EVDS and on a vaccine passport, which may be necessary for overseas travel.
  • Data from the Ensemble 2 trial shows excellent levels of protection from two doses of J&J given 56 days apart. The global trial in 31300 participants found 100% protection against severe-critical COVID-19 and 75% protection against symptomatic (moderate-severe) COVID-19. No new safety concerns were identified.
  • A booster dose of J&J given six months after the first dose caused antibodies to increase 9-fold one week after the booster and continued to rise to 12-fold higher four weeks after the booster.
  • Participating in this study will help contribute to much needed “real world data” and could help the government to make decisions about the type and timing of booster shots in 2022.

Cons of having J&J Booster now:

  •  The booster is administered as part of a trial, so you have to sign a consent form to be part of the study. However, everyone on the study receives a “real” vaccine (there are no placebos) and there is no active follow up involved – Sisonke asks consent to access medical records should you have any side effects or become infected with COVID-19.
  • Immunogenicity data shows that Antibody responses mounted after a J&J booster are not as good as those mounted after an mRNA (Pfizer or Moderna) booster. It is still unknown whether this translates into inferior efficacy, as the effects have not been measured, and may show equivalent and durable long term protection. The real world Sisonke trial is a way of getting answers to this.

Pros of having the Pfizer Booster:

  •  Immunogenicity data shows better antibody response using Pfizer as a booster compared to J&J (following primary vaccination with J&J). Antibodies were demonstrated to increase 32-fold in people who received a Pfizer booster following primary vaccination with J&J. It is not yet sure what the difference in efficacy will be.
  •  No new safety concerns have been identified in the small studies done using this regime.

Cons of having the Pfizer Booster:

  • SA Department of Health is not yet offering a Pfizer booster. It can thus only be done “illegally” – using another passport or having an unrecorded dose. There is no way of registering this on EVDS, thus there is a risk of not appearing fully vaccinated on an official vaccine passport.
  • It is unknown when Pfizer boosters will officially be rolled out by DOH – waiting for it may mean that Healthcare workers have waning immunity and are vulnerable when the 4th wave arrives.
  • SAHPRA has still not approved a Pfizer boost as they have not received sufficient safety and efficacy data.

I had a J&J earlier in the year, and managed to get an unauthorized Pfizer booster, should I have another J&J now as part of Sisonke 2 trial?

  • The recommendation is to definitely NOT have a J&J if you have already had an undocumented Pfizer booster.
  •  There is no safety data on this regime and the Sisonke consent specifically excludes anyone who has already received a booster.

I had a J&J and an unauthorised Pfizer booster, can I get it registered?

  • There is no way of registering unauthorised booster doses on EVDS.
  • This may be a problem for SA vaccine certificates going forward.

booster for healthworkers

I have had a J&J followed by a Pfizer, should I get another Pfizer dose once this is offered?

  • There is no data on this as yet.
  • If Pfizer boosters are offered by DOH at some stage, this may be a way of getting full certification, but once again, safety data does not exist.

I had covid-19 after my first J&J – should I still get a second dose?

  • According to information from Sisonke, “You will still get extra benefit from a booster vaccination if you had COVID-19 after your first dose. If you have tested positive for COVID-19 in the past 30 to 35 days, we recommend that you wait for at least 30 days after you tested positive. If you required admission because of COVID-19, we recommend that you discuss the timing of boosting with your health provider.”

I had severe side effects after my first J&J – is it safe to get another dose?

  •  Most people experienced mild side effects after the first J&J dose (pain at injection site, headache, fever, nausea, dizziness) and can probably expect similar after the booster dose. These usually resolve in 1 to 3 days.
  • Side effects are reportedly LESS severe after the second J&J dose (in contrast to the second Pfizer dose, which usually causes a worse reaction).
  • A very rare side effect after J&J is TTS/ thrombocytopenia (low platelets) and anybody who experienced this should not have a second dose. Other very rare but serious side effects following J&J are anaphylaxis and Guillain Barre Syndrome.
  • Anybody who has a history of clotting following the first vaccine or a clotting disorder in general needs to be evaluated on an individual basis by their own doctor and should contact the Sisonke safety team before accepting a second dose. SISONKE Desk can be contacted on 0800 014 956 or here.

Conclusions regarding Booster Vaccinations

Most vaccines, including Polio, Tetanus, Measles, Hepatitis and Influenza vaccines, require booster doses to ensure sustained and long-lasting immunity. COVID-19 vaccines are no different and South Africa will follow other countries in the rollout of boosters.

At the moment, the only available booster in South Africa is J&J for Healthcare workers who participated in Sisonke ahead of the expected 4th wave. Going forward it is likely that heterologous boosters will also be offered. However protection from the primary vaccination remains reasonably effective at six months, and most South Africans will have to wait for boosters until next year.

In the meantime it remains crucial for as many people as possible, and particularly vulnerable groups, to have a first vaccine, to reduce the impact of potential new variants that may arrive.

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Dr Sheri Fanaroff

Dr Sheri Fanaroff

Dr Sheri Fanaroff MBBCh FCFP MFamMed, a Family Physician, practicing in Melrose, Johannesburg. Fanaroff is a member of GGPC (Gauteng General Practitioners Collaboration) which has created a platform for doctors to share resources during Covid-19. Look for #voicesthatcare on the GGPC Facebook page.

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