Scientists who studied the COVID-19 outbreak in Massachusetts concluded that vaccinated people carry about the same coronavirus load as those who did not get the vaccine.
US health officials released a detailed list on Friday, 30 July, which was key in this week's decision by the Centers for Disease Control and Prevention to recommend that vaccinated people return to wearing masks indoors in parts of the US where the delta variant is fueling infection surges.
Experts have also suggested to the CDC that the mask guidance should be expanded to include the entire country, even outside the hotspots.
Can people who are fully-vaccinated spread COVID-19? Are the symptoms less severe in fully vaccinated individuals? Here’s everything you should know.
Can people who are fully-vaccinated get COVID-19?
The existing vaccines were developed with respect to the original SARS-COV-2 virus. The new variants are said to have the ability to escape the vaccine-induced immunity, making even the fully vaccinated susceptible to infections, studies point out.
If a person contracts COVID-19 after receiving both doses of the vaccine, a breakthrough infection occurs. The person either remains asymptomatic or develops mild to moderate symptoms.
The Centre for Disease Control and Prevention (CDC) has said that even though there have been instances of breakthrough infections, it is rare and infected people are less likely to be sick, The Times of India reported.
What are the symptoms of coronavirus infection in vaccinated people?
According to the study, among those fully vaccinated, about 80 percent experienced common symptoms such as cough, headache, sore throat, muscle aches and fever.
Are the symptoms less severe in fully vaccinated individuals?
According to CDC, the chance of fully vaccinated individuals to experience severe symptoms from COVID-19 is rare. However, it also clarified that fully vaccinated people can still experience severe infections, enough to require hospitalisation and can also result in fatalities.
Are vaccinated people less likely to spread the virus?
A team of researchers conducted a study at China's Guangdong Provincial Center of Disease Control and Prevention claimed that the transmission of the SARS-COV-2 virus depends on the amount of viral load a person has in his or her system.
The vaccines can lower the level of viral load in a person, it is less likely that vaccinated individuals can become silent carriers, the Chinese study said.
However, a study in the United States' Massachusetts, after all COVID-19 restrictions were lifted, showed the contrary.
What does the US-based study say about transmission of virus by fully vaccinated people?
Provincetown, a seaside tourist spot on Cape Cod in the county with Massachusetts has so far reported more than 900 cases (until July). Three-quarters of cases reported were people who were fully vaccinated.
Of this, 470 Covid-19 cases linked to the Provincetown festivities – which included densely packed indoor and outdoor holiday events at bars, restaurants, guest houses and rental homes, the study said.
According to Dr Angela Rasmussen, a virologist at the University of Saskatchewan, the measure researchers used to assess how much virus an infected person is carrying does not indicate whether they are actually transmitting the virus to other people.
The study is ongoing and more data is expected to come over this.
What measures should vaccinated people should continue take?
People who are not yet vaccinated need to be more careful. Fully vaccinated individuals should continue taking all the precautionary measures such as maintaining social distancing and wearing masks.
They are currently tracking breakthrough cases as part of much larger studies that involve following tens of thousands of people who are vaccinated and the ones who are not across the country over time, India Today reported. Watch this space for more.
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