If you have taken a Pfizer Covid-19 vaccine – here’s what you should know about a third ‘booster’ shot
Pharmaceutical companies Pfizer and BioNTech have submitted data to the US Food and Drug Administration (FDA) to support the evaluation for a third dose of the Covid-19 vaccine.
The companies said in a statement that people who received a third jab of the mRNA vaccine showed “a favourable safety profile and robust immune responses.”
This data also will be submitted to the European Medicines Agency (EMA) and other regulatory authorities in the coming weeks.
“Vaccination is our most effective means of preventing Covid-19 infection – especially severe disease and hospitalization – and its profound impact on protecting lives is indisputable,” said Albert Bourla, chairman and chief executive officer of Pfizer.
“Still, with the continuing threat of the delta variant and possible emergence of other variants in the future, we must remain vigilant against this highly contagious virus.”
Bourla said the data suggests a third dose of Pfizer’s vaccine elicits antibody levels that significantly exceed those seen after the two-dose primary schedule.
“This initial data indicate that we may preserve and even exceed the high levels of protection against the wild-type virus and relevant variants using a third dose of our vaccine,” said Ugur Sahin, chief executive and co-founder of BioNTech.
“A booster vaccine could help reduce infection and disease rates in people who have previously been vaccinated and better control the spread of virus variants during the coming season.”
Pfizer noted reports of adverse events following the use of its vaccine, which suggests increased risks of myocarditis and pericarditis, particularly following the second dose.
In clinical studies, adverse reactions in participants 16 years of age and older include:
- Pain at the injection site (84.1%);
- Fatigue (62.9%);
- Headache (55.1%);
- muscle pain (38.3%);
- Chills (31.9%);
- Joint pain (23.6%);
- Fever (14.2%);
- Injection site swelling (10.5%);
- Injection site redness (9.5%);
- Nausea (1.1%);
- Malaise (0.5%);
- Lymphadenopathy (0.3%).
In a clinical study, adverse reactions in adolescents 12 through 15 years of age include:
- Pain at the injection site (90.5%);
- Fatigue (77.5%);
- Headache (75.5%);
- Chills (49.2%);
- Muscle pain (42.2%);
- Fever (24.3%);
- Joint pain (20.2%);
- Injection site swelling (9.2%);
- Injection site redness (8.6%);
- Lymphadenopathy (0.8%);
- Nausea (0.4%).
Debate is also accelerating in the US and Europe over whether booster shots will be needed, and if so, when and in which subgroups of patients, Bloomberg reported.
Pfizer has cited data suggesting the efficacy of its vaccine against mild cases may start to fade after around six months, even though protection against severe cases remains strong. Meanwhile, Moderna Inc has said trial results show that its vaccine held up well over six months. But executives from both companies have argued that people will eventually need booster shots.
Earlier this month, a preliminary study conducted by Israel’s largest health maintenance organisation found that most people who received a booster shot of the Pfizer Inc-BioNTech SE Covid-19 vaccine had similar or fewer side effects than they did after the second dose.
Of the 4,500 respondents to the survey, 88% reported “a similar or better feeling” than their reaction to the previous dose, with 31% saying they had localized effects like pain or swelling in the area of injection, according to a statement from Clalit Health Services earlier in August.
Approximately 15% of people had other symptoms like tiredness, muscle aches or fever. Less than 1% reported difficulty breathing or chest pains, Bloomberg reported.
Israel became the first country in the world to disseminate booster shots widely in a bid to quell a surge in new cases.
Vaccines in South Africa
As of Monday (16 August), the total number of vaccines administered in South Africa is 9,557,542.
The vast majority of these vaccines are from Pfizer (7,431,606), with 5,360,100 people receiving their first shot and 2,071,506 receiving their second shot to date.
By comparison, 2,125,936 single-dose Johnson & Johnson vaccines have been administered, according to the National Institute for Communicable Diseases (NICD), a division of the National Health Laboratory Service.
The institute reported 7,983 new Covid-19 cases in South Africa, representing a 21.1% positivity rate. As per the National Department of Health, a further 299 Covid-19 related deaths have been reported, taking total fatalities to 77,440 to date.
The total number of vaccines administered in the past 24 hours is 158,103.
Health minister Dr Joe Phaahla said that the government plans to open Covid-19 vaccines to all adults in South Africa weeks earlier than expected.
The country is officially set to open vaccinations to people between 18-35 from 1 September. However, Phaahla said his department is in consultations to move this date up to the end of this week – 20 August.
“We are in further consultations with our leadership in cabinet, (and) we will probably before the end of this week open for all adults above 18,” he told 702. “If not this week, then not later than next Monday (23 August) for all adults.”
Booster shots may be necessary
Data published this week shows that Moderna’s vaccine may be the best option against the Delta variant of Covid-19 – and that a booster shot may be necessary if you have taken any of the other available vaccines.
In a study of more than 50,000 patients in the Mayo Clinic Health System, researchers found the effectiveness of Moderna’s vaccine against infection had dropped to 76% in July when the delta variant was predominant.
This was down from 86% in early 2021, Reuters reported.
Over the same period, the effectiveness of the Pfizer/BioNTech vaccine had fallen to 42% from 76%, the researchers said.
While both vaccines remain effective at preventing hospitalisation, a Moderna booster shot may soon be necessary for anyone who got the Pfizer or Moderna vaccines earlier this year, said Dr Venky Soundararajan of Massachusetts data analytics company conference, who led the Mayo study.
A separate Ontario study corroborated the findings that found that the Moderna vaccine produced stronger immune responses than the Pfizer vaccine.
“We continue to believe a third dose booster may be needed within 6 to 12 months after full vaccination to maintain the highest levels of protection,” a Pfizer spokesperson told Reuters.
Read: South Africa to open Covid-19 vaccines to all adults in the next week: health minister
Loading ...
