Fourth Vaccine Shot Less Effective Against Omicron
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According to research from an Israeli hospital, a fourth dose of COVID-19 increases antibody levels, but doesn’t provide sufficient protection against Omicron variant infections.
USA Today – The preliminary results were released Monday and challenge the notion that a booster dose is required to stop the spread of coronavirus.
“Despite increased antibody levels, the fourth vaccine only offers a partial defense against the virus” Gili Regev-Yochay MD, director of the hospital’s infection prevention and control units, told reporters.
“The vaccines are more effective against earlier variants, offer less protection versus Omicron,” she said.
In a study 274 medical personnel at Sheba Medical Center near Tel Aviv received a fourth vaccine dose in December — 150 received the Pfizer vaccine and 120 got the Moderna vaccine, after having previously received three Pfizer shots.
Regev-Yochay noted that both groups received an increase in antibodies that was “slightly more” than following the third shot. However, Omicron spread was not prevented when the fourth dose was given to an uncontrolled group.
“We see many infected with Omicron, who received the fourth dose,” Regev-Yochay said. “Granted little less than the control group however, there’s still a lot of infections.”
Some health officials in Israel claim that the push for fourth doses is worth it, according to The Times of Israel. Regev-Yochay said that the vaccine remains effective against the Alpha and Delta variants. He advised that older adults and those at higher risk of severe COVID-19 get a fourth dose.
Sheba Medical Center issued a statement just hours after releasing the preliminary results. It called for “continuing vaccination campaigns for high-risk groups even though the vaccine may not offer the optimal protection against infection with this particular variant.” The Times of Israel reported that the hospital was compelled to release the statement due to the Israeli Health Ministry didn’t like the release of early study results.
The third booster “returns the level of antibodies to what it was prior to the start of the third booster” Nachman Ash, MD, director of Israel’s Health Ministry, told Channel 13 TV in Israel according to The Associated Press.
He added, “This is of great importance, particularly for people who are older.”
According to the AP More than 500,000 Israelis received their fourth doses of the drug since it was first made available to doctors, patients with immune-compromised, and people who are 60 and over. The country is also facing an outbreak of coronavirus that has seen record numbers of infections and increased hospitalizations.
On Tuesday the Israeli government said it would reduce the mandatory quarantine period from 7 days to just 5 days, the AP reported.
“This decision will enable us to ensure public health on one hand and keep the economy going at this time on the other hand, even though it is difficult to navigate this storm with confidence,” Prime Minister Naftali Bennett said.
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