You did everything you could to stay safe. You socially distanced. You wore a mask. You avoided large gatherings and unsafe indoor environments. When the coronavirus vaccine became available, you got in line and got your shots. Now that eight months have passed, you're getting ready to get a booster.
And now, you think, finally, it's time to throw caution to the wind and return to the life you lived pre-pandemic.
I wish I could tell you that was the case. But for your safety and the safety of those around you -- including kids who are about to start getting their vaccinations -- it's time to take a deep breath, tap the brakes, continue using your mask indoors, and not re-engage with large crowds just yet.
Here are five reasons why.
1. Your body needs time to build immunity to COVID-19.
The three authorized COVID-19 vaccines remain incredibly effective at preventing even mild infections. When first authorized, Pfizer and Moderna's vaccines proved 95% and 94% effective, and Johnson & Johnson's single-shot vaccine proved 75% effective.
Nevertheless, studies have shown that all three vaccines lose some ability to protect against infections over time. For that reason, experts recommend that people in high-risk groups -- such as older adults and people with weakened immune systems -- get booster shots.
Like the initial vaccines, booster shots have been shown to be extremely effective at preventing serious illness. In fact, new research shows that people who received booster shots were at a 93% lower risk of being hospitalized and an 81% lower risk of death from COVID-19 compared to people who had only received their initial two shots.
The booster builds on the immunity protection you have developed through your primary vaccination series. But the added protection from a booster doesn't happen overnight.
"The booster doesn't work right away; it takes a week or so to have full effect," says Dr. Megan Ranney, an associate professor of emergency medicine at Brown University. "I frequently see people who take risks before the vaccines have had a chance to protect them."
Instead, said Ranney, people should continue to take common-sense precautions. "Wash your hands, maintain a little distance and, if you are in an area with high COVID prevalence, wear a mask when you are in crowded public indoor locations," she said. The guidance about masking indoors doesn't change, regardless of whether someone has had two doses or three doses of vaccine.
How will you know your immune system is building a response to COVID? You'll likely feel some side effects. These could include pain at the injection site, fatigue, headache, muscle aches, joint pain and fever.
You can predict what type of side effects you might develop based on which ones you experienced with your previous shots. If your arm hurt for a couple of days last spring, it will likely hurt for a couple of days after you get a booster.
Remember that these side effects are generally mild and temporary, and the vaccines can provide long-lasting protection against COVID-19. Whatever you may experience, it's crucial to understand that side effects are generally a good sign. They mean your body is responding to the vaccine and building immunity to COVID-19 infection.
2. COVID-19 is still a risk.
Getting a booster shot doesn't guarantee you won't be infected with the coronavirus. But it can help your immune system build protection against severe disease or hospitalization -- including from the delta variant.
So in order to protect yourself and those around you from infection, continue to follow public health guidance and regulations in your local area regarding masking and social distancing. Both of those, as well as washing your hands regularly with soap and warm water, will provide you with maximum protection against the coronavirus and other viruses circulating this fall and winter as more people are out and about.
3. It's flu season.
We've spent so much time talking about COVID-19 that we may lose sight of the health effects posed by the very common influenza virus, which usually pops up in early autumn and can lead to serious illness.
During the 2019-2020 flu season, 38 million people became sick with flu, resulting in more than 400,000 hospitalizations and 22,000 deaths. Studies have shown that levels of flu last year were at their lowest since 1997, the first year for which data is available. That's likely because people wore masks, used hand hygiene often, and socially distanced, in order to suppress the spread of COVID-19. Those actions also had the effect of suppressing the flu.
Unfortunately, last year's mild flu season might lead to a more severe flu season this year, the Centers for Disease Control (CDC) has warned. That's because people weren't exposed to flu last year, so they didn't build up an immunity to the virus.
The good news is that flu vaccines are widely available. In fact, the CDC says it's perfectly safe to get the COVID and flu vaccines during the same visit. So whether or not you get a booster shot, "we should always prepare for the flu season by planning to get vaccinated," Dr. David Hirschwerk, an infectious disease specialist at Northwell Health in New York, told ABC News.
In the meantime, masks, hand-washing and all of the other measures that you used to protect against COVID-19 will generally also protect you against flu.
4. Other viruses are out there.
No, they're nothing to panic about -- but just as with flu, the CDC warns that there's likely to be a resurgence of other non-COVID-19 respiratory viruses this year. These include adenovirus and respiratory syncytial virus (RSV), which are frequent causes of the common cold during the winter months.
COVID-19 shutdowns and other precautions kept RSV from spreading during the winter of 2020-21. But when the shutdowns ended in the spring, RSV numbers started to rise. In fact, the CDC warns it has "observed an increase in RSV detections reported to the National Respiratory and Enteric Virus Surveillance System (NREVSS), a nationwide passive, laboratory-based surveillance network."
With a resurgence of these viruses, you want to be careful that you don't increase your risk of exposure to them while you're reinforcing your COVID-19 protection. Though you won't be more susceptible to these other viruses the week after you take the booster, it will make it difficult to determine whether any symptoms you exhibit are side effects from a booster shot or actual symptoms of illness. I would suggest waiting a week after your booster before participating in any medium- or large-sized gatherings, and using an elbow or fist bump rather than shaking hands.
Dr. Sachin Jain, a doctor of internal medicine who serves as president and CEO of SCAN Health Plan, also cautions people against spreading common cold viruses because they can have outsized effects on older adults. "Some older adults, especially those with chronic illness, can be more susceptible to viruses like RSV," said Jain. "For that reason, it's best to keep practicing behaviors that will protect the health of older adults in our communities."
These viruses might pose an even greater threat to those with long-term COVID-19 symptoms, known as long COVID. "Those with long COVID may be at higher risk for other infections such as flu and RSV, based on their immune status and history of pre-existing conditions," said Dr. Sritha Rajupet, primary care lead for the Post-COVID Clinic at Stony Brook Medicine in New York. "Preventive measures such as vaccination against flu, shingles and pneumonia, to name a few, are essential."
5. Community transmission matters.
Even though you may have gotten your vaccinations, the COVID-19 virus is still prevalent in many communities. And the best way to protect yourself and others is through what ABC News contributor Dr. John Brownstein calls "layers of protection."
"For many, boosters provide additional protection for those that have underlying concerns of severe disease or increased risk of exposure," said Brownstein, an epidemiologist and chief innovation officer at Boston Children's Hospital.
Nevertheless, Brownstein said, "If community transmission continues to be high, it's important to follow public health guidance regardless of your number of shots."
So yes, if you're an older adult or your body is immuno-compromised, it's a good idea to get a booster shot. But that doesn't mean it's time to brush aside those public health measures that keep us, our loved ones, and our communities safe.
Dr. Jay Bhatt, an ABC News contributor, is an internal medicine physician and an instructor at the University of Illinois School of Public Health.