In light of recent data showing that only 40% of eligible Londoners have received their Covid boosters, NHS England is urging people to do so before June 30.
Prof. Danny Altmann, a specialist at Imperial College London, said he thought people had grown numb to the disease's dangers.
According to the vaccination expert, the virus was still "causing misery.".
The spring booster vaccination will be discontinued from the NHS seasonal program after the June deadline.
The vaccination program's rollout started in England on April 3, with older care facility residents, people over 75, and children over five who are extremely clinically vulnerable being eligible for vaccinations.
Nevertheless, only 266,000 of the potential 670,000 Londoners have received vaccinations to date, according to NHS data.
Vaccinated individuals can contract Covid-19, but they are much less likely to develop a serious illness or pass away as a result of the virus.
Prof. Altmann stated that he thought the low uptake was a result of people becoming "complacent" about the disease because it was "still there all around you" in a mistaken way.
We're still in the rough, he continued.
We live in a nation with a high prevalence of chronic illness; businesses, like the NHS, have staffing gaps; people frequently miss work or school due to illness; and 3 percent of the population has long-term COVID. ".
Our nation has "taken our foot off the gas" in combating the virus, he claimed.
According to NHS England, more than half of all eligible individuals—3.6 million people—have already received a spring booster.
More than 240 sites in London and 2,500 sites throughout England, according to the statement, offer booster shots.
The low attendance for vaccinations at Dr. Rosemary Leonard's Dulwich office surprised her, according to the south-east London doctor.
According to her, recently, staff members had trouble filling vaccine appointments. When scheduled patients did not arrive, she was also forced to discard vaccine supplies.
She stated, "I believe there is a perception that Covid has vanished.
"People don't see it as a risk, and they also think that because they've had so many booster shots, they must already be immune.
"People are Covid-vaccinated out," she claimed.
She did note that the vaccine's protective effects start to wear off after five to six months.
"A cohort of older individuals who are more susceptible to serious illnesses from Covid will emerge.".
The World Health Organization (WHO) declared Covid-19 to no longer be a "global health emergency" last month.
But according to the WHO director, the pandemic claimed at least seven million lives.