Some beachgoers continue to wear masks in San Diego. Photo by Chris Stone

Each day, there seems to be a lot of news — both negative and positive — related to the COVID-19 pandemic. Lately, the bad news is that the more contagious delta variant is causing a surge of new cases and hospitalizations, especially among people who have not yet received a COVID-19 vaccine. The good news is that more people are getting vaccinated on a daily basis — though not nearly enough to end the pandemic.

While those who are fully vaccinated — at least 2 weeks have passed since receiving their second dose of either the Pfizer or Moderna vaccine, or single dose of the Johnson & Johnson vaccine — are largely avoiding infection, there is a small risk of “breakthrough infections.” And not all vaccinated people will have the same experience if they are exposed to the coronavirus.

Everyone reacts differently when exposed to a virus. Some people will experience infection, some won’t. Some will experience symptoms that others don’t, or will experience them at a lesser or greater severity than others. The important thing to remember is that vaccination is highly effective at protecting you against serious illness, hospitalization and death. Any breakthrough cases will likely result in no symptoms or very mild symptoms.

What Do the Numbers Tell Us?

While case numbers are increasing — predominantly among the unvaccinated, but also among a very small number of people who have been fully vaccinated — a recent report showed that the rate of cases in vaccinated individuals is below 1% in all states that are tracking breakthrough cases.

Additionally, in states cross the U.S., roughly 90% to 99% of people hospitalized with COVID-19 are unvaccinated. Of the small percentage of hospitalized people who have been vaccinated, many of them have other risk factors, such as advanced age, chronic illness or a compromised immune system.

Are the Vaccines Still Working?

With this slight increase in breakthrough infections, many have wondered if the protection initially provided by the vaccines has decreased over time. While vaccines remain extremely effective at preventing severe illness and death, they may not be as effective at preventing infection or transmission as they were before the emergence of the delta variant.

However, experts agree the effectiveness of the vaccines is still considered impressive, even against the delta variant. According to a recent U.K. study, the vaccines are currently 79% effective against COVID-19 infection and 88% effective against symptomatic COVID-19.

It is more likely that the unique characteristics of the delta variant are causing the increase in cases, both in the unvaccinated and vaccinated. Unlike the original coronavirus that causes COVID-19 or its other variants, studies show the delta variant:

  • Is more contagious for both adults and children
  • Is associated with a higher viral load of infection and a longer phase of transmissibility (can be spread more widely and rapidly)
  • May lead to infections in vaccinated people that spread as easily as infections among unvaccinated people
  • May cause more severe illness

These differences have led the Centers for Disease Control and Prevention to acknowledge that “the war has changed.” The focus, they say, must now be on vaccinating as many people as possible, but also on encouraging people to identify their own personal risk — and the risk of loved ones — for severe illness, and taking steps to decrease that risk.

This means that everyone — vaccinated or not — should consider the transmission rate of COVID-19 in their community and vaccination rate of the people surrounding them, and act accordingly. The CDC now recommends that fully vaccinated people wear a mask in public indoor spaces, which is especially crucial if people are at increased risk for severe illness from COVID-19 or if they have someone in their household who is at increased risk of severe illness or is not fully vaccinated. This includes children under age 12, who are not yet eligible to receive a COVID-19 vaccine.

Additionally, vaccinated individuals should get tested if experiencing symptoms of COVID-19 — including headache, sore throat, runny nose and fever. The vaccinated should also be tested 3 to 5 days after a known exposure to someone with suspected or confirmed COVID-19 and wear a mask in public indoor settings and around others for 14 days or until they receive a negative test result.

Do Vaccinated People Need a Booster?

While the Food and Drug Administration amended the emergency use authorization (EUA) for the Pfizer and Moderna COVID-19 vaccines to allow fully vaccinated people with compromised immune systems to receive a third dose, and the CDC recently recommended that people who received the Pfizer mRNA vaccine and are age 65 or older, live in a long-term care facility, or are at increased risk for severe illness receive a booster shot, officials say they will continue to review the data before granting approval for an additional dose of the vaccines for all fully vaccinated populations.

There is no denying that community spread, along with increased hospitalizations and deaths, is occurring primarily among people who are unvaccinated. So, our first priority is to get these individuals their first and second doses while we wait for further guidance on the need for a booster for all those already vaccinated.

Vaccinating as many people as possible within communities will not only save lives, but also slow the spread of COVID-19, prevent the development of further variants, and allow us to more quickly return to normalcy. If you haven’t already, please get vaccinated.

Jyotu Sandhu, MD, is a family medicine doctor with Sharp Rees-Stealy Medical Group.

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