COVID-19 vaccine
COVID-19 vaccineiStock

While Israel hailed the arrival this week of the first doses of the coronavirus vaccine developed by Pfizer and BioNTech, the vaccine’s ability to return life to normal may be limited, an expert has warned.

Michal Tal, an immunologist at Stanford University, hinted that some of the optimism regarding the impact of the new vaccines developed by Pfizer and Moderna may be overblown, according to a report by The New York Times.

Tal noted that the high efficacy rates reported by Pfizer and Moderna for their vaccines – both rated at over 90% effectiveness – relate only to the ability of the vaccine to prevent vaccinated individuals from developing symptomatic cases of the virus.

Vaccinated, asymptomatic people may still be able to spread the virus to others, Tal warned, including to people in high-risk groups.

Tal cautioned that until the effect of the vaccines is better understood, even those immunized with the vaccines must continue to wear masks in public.

“A lot of people are thinking that once they get vaccinated, they’re not going to have to wear masks anymore. It’s really going to be critical for them to know if they have to keep wearing masks, because they could still be contagious.”

While the vaccines are injected into arm muscles, prompting the body to produce antibodies, the coronavirus spreads primarily via mucous from the nose, where the virus tends to build up the most.

It remains unclear how many antibodies created following vaccination circulate to the nasal mucosa, leaving the vaccines’ effectiveness in preventing the vaccinated from spreading the virus an open question.

On Wednesday, Israeli Prime Minister Binyamin Netanyahu announced that Israel is slated to begin vaccinating its citizens with the Pfizer/BioNTech vaccine on December 27th, and is aiming to provide 60,000 doses per day.

"The first vaccines will be given on December 27. We are prepared to provide 60,000 vaccines a day. I wanted to set an example and be the first person to be vaccinated in Israel," Netanyahu said.