Infection possible despite inoculation, experts warn

A 64-year-old woman from Bengaluru, who had received the first dose of the Covid vaccine in the first week of March, developed typical symptoms of the disease a week ago.

Refusing to believe it could be Covid since she had received the vaccine, the family members ignored the symptoms. That was until she developed breathlessness on Thursday and had to be rushed to hospital. Tests confirmed she has Covid. Her oxygen saturation level had dropped to 70% (normal 95%) and she is currently on oxygen support in ICU at Vagus hospital.

Doctors treating her say there is a lack of awareness among the public on how the vaccine works, and people erroneously believe that one shot of the vaccine would protect them from infection.

“Immunogenicity develops only a fortnight after the second dose,” said Dr Chetan Kumar NG, pulmonologist, Vagus hospital, who is treating the woman. “Even then, the vaccine may not provide protection against newer strains of the virus. However, the vaccine will prevent a person from getting a severe form of disease. Getting infected is still possible and no one should ignore symptoms or wait until they worsen.”

There are instances of healthcare workers, including doctors, who have taken two doses of the vaccine who have still tested positive. For example, an ENT surgeon in a private hospital tested positive even after taking the second dose. While the doctor had a mild infection and was in home isolation, his wife who was not vaccinated, developed moderate disease and is still being treated in a hospital.

In another private hospital, a community medicine specialist, who was fully inoculated, tested positive and is now in home isolation.

Dr MK Sudarshan, chairperson, Covid-19 technical advisory committee, said the vaccine prevents the disease and its progression to severe form, but not the infection itself. He said the Covid-19 vaccine provides protection against a severe form of the disease only 15 days after the second dose.

“The virus can infect a vaccinated person too,” Dr Sudarshan said. “Infected people may be asymptomatic or have mild infection but can still transmit the virus to others. The vaccine does not liberate anyone. Wearing a mask protects a person from outside and a vaccine protects one from inside by preventing the disease.” He said people who have received the vaccine must not refuse testing.

“In most of the cases, the vaccinated person, if infected, will not require hospitalisation. It is essential to strictly follow Covid-appropriate behaviour even after taking the doses. People must wear masks, ensure hand hygiene and avoid crowds. Vaccine does not provide complete freedom from Covid,” he said.