Earth Essences.Com

Pfizer fourth booster vaccine: Three side effects to expect from fourth dose - new trial

The coronavirus vaccine has positively altered the course of the pandemic, slashing hospitalisation and death rates across the nation. But waning protection has presented the latest hurdle in the vaccination drive. In a bid to tackle dwindling immunity, thousands of vulnerable individuals will be called forward for a top-up this week. Data obtained from an Israeli study earlier this year has outlined some side effects to expect.

Preliminary data released in January revealed that side effects from a fourth dose of the Pfizer BioNTech vaccine are mild.

The findings were obtained during the Sheba Medical Centre trial in January, which administered the second booster jab to its staff amid a nationwide surge in Omicron infections.

A fourth dose of the Pfizer and BioNTech vaccine was administered to 150 medical personnel whose antibody levels had significantly dropped since receiving their third dose between four to five months prior.

Researchers did not pick up on any marked differences between the side effects of the fourth and third doses of the vaccine.

Side effects of Pfizer's

The Medical Centre did however note that side effects included pain, fever and headaches, reported Reuters.

The Israeli study, conducted by the Sheba Medical Centre in January, also revealed that the fourth booster dose increased antibody count fivefold within a week of receiving the dose.

To date, the most common side effects to follow the third dose have been body aches, headaches and fatigue, with some individuals complaining of chills and swollen lymph nodes.

Scientists have stressed that such after-effects are an indication of the immune system responding to the shots.

Israeli Prime Minister Naftali Bennet told reporters in January: "A week into the fourth dose, we know to a higher degree of certainty that the fourth dose is safe.

"The second piece of news [is] we know that a week after administration of a fourth dose, we see a fivefold increase in the number of antibodies in the vaccinated person.

"This most likely means a significant increase against infection and hospitalisation and severe symptoms."

Earlier this month the medical centre published a report in the New England Journal of Medicine, outlining the efficacy of a fourth dose.

The findings confirmed that the fourth dose "did not lead to substantial adverse events despite triggering mild systemic and local symptoms in the majority of recipients".

However, the study authors said that adding the fourth dose for people inoculated and boostered with the Pfizer-BioNTech shot may only have "marginal benefits".

They added: "Our cohort was too small to allow for accurate determination of vaccine efficacy.

"However, within the wide confidence intervals of our estimates, vaccine efficacy against symptomatic disease was 65 percent at most."

It comes as coronavirus cases have surged across the country, with infections among over-70s reaching record heights.

Second Booster

What's more, survey data released earlier this month showed almost five percent of the population had Covid.

However, health secretary Sajid Javid has said he remains confident the "vaccine wall of defence" will keep the situation stable.

The recent surge has been put down to the lifting of restrictions across the country, which has led to increased social mixing.

The health secretary told BBC1's programme earlier this week: "Our levels of concern haven't changed. Although the case numbers are rising, infections are rising, and indeed hospital numbers are rising, they are still way below their peak." 

Reference: Daily Express: Solen Le Net