COVID-19 vaccines are effective tools to stop the spread of the virus, as proven by multiple studies conducted before they were released to the public. However, no vaccines are 100% effective and promise at preventing illness as there will be a small percentage of the vaccinated population who will get sick or hospitalized from COVID-19. These cases are called breakthrough infections.

The Delta variant has recently caused increased numbers of infections, prompting health agencies to remind the public of the health protocols to prevent more cases.

Due to some breakthrough infections, many people have started asking how effective vaccines truly are and whether they could also transmit the virus to other people.

(Photo: Getty Images)
Pedestrians walk past a sign asking members of the public to social distance due to Covid-19, in central London on June 7, 2021. - The Delta variant of the coronavirus, first discovered in India, is estimated to be 40 percent more transmissible than the Alpha variant that caused the last wave of infections in the UK, Britain's health minister said Sunday. (Photo by Niklas HALLE'N / AFP) (Photo by NIKLAS HALLE'N/AFP via Getty Images)

What Should Fully-Vaccinated People Do When Exposed to Infected Patients?

For fully vaccinated people exposed to COVID-19 patients and who developed symptoms like cough, congestion, or loss of taste and smell, they should get tested.

According to Business Insider, symptomatic fully vaccinated people should start with rapid tests, about 72% effective at identifying COVID-19 infections in symptomatic people. A rapid test at home is also accepted.

But a more accurate test is the PCR test that looks for other viruses, like rhinovirus or seasonal coronavirus. Amesh Adalja, the senior scholar at Johns Hopkins Center for Health Security, told Insider that many viruses with flu-like symptoms had come back as people began socially interacting again.

However, for fully vaccinated people exposed to COVID-19 patients but did not experience any symptoms, experts said that they are probably in the clear. The Centers for Disease Control & Prevention (CDC) only recommends vaccinated people to get tested or quarantine if they have symptoms of COVID-19.

Paul Offit, director of the Vaccine Education Center at Children's Hospital of Philadelphia, said that if vaccinated people do not experience symptoms after a week of being exposed to a patient, they could be free from the virus.

But some experts still recommend getting tested even if asymptomatic to not risk missing a more dangerous "escape variant."

ALSO READ: Johnson & Johnson COVID-19 Vaccine Less Effective Against Delta Variant With Only 33% Efficacy Rate

Why Are There Breakthrough Infections?

COVID-19 vaccines are effective, but some fully vaccinated people could still catch the virus, the CDC said. These breakthrough infections are a small percentage of fully vaccinated people who might experience symptoms or not.

Large-scale studies found that vaccines prevented most people from COVID-19. There has been some evidence as well that mRNA COVId-19 vaccines offer similar protection in real-world conditions. But none of the vaccines available today could 100% prevent the illness. This means that for any vaccine, breakthrough infections are possible.

Moreover, the health agency said that fully vaccinated people could be infected before or just after vaccination. It takes about two weeks for the body to build protection against the virus, so they can get sick if the vaccine did not get enough tie to provide protection, especially against the new variants.

Most of those who get infected despite being vaccinated experience less severe symptoms, although some may still be hospitalized and die. But experts said that vaccines are still effective protection against the deadly virus. The CDC is now investigating a pattern in breakthrough infections in the country.

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