MILWAUKEE — Wisconsin’s vaccine rollout is in full swing.

What You Need To Know

  • Some flu-like symptoms are normal after the vaccine, but talk to your doctor if you have severe or long-lasting reactions

  • You're considered "fully vaccinated" two weeks after your last shot, since your immune system needs time to build up a response

  • Gathering in small groups is OK, but stick with other vaccinated or low-risk people 

  • Even though vaccines are working well, cases are still rising in Wisconsin

As of earlier this month, everyone over 16 is eligible to sign up for an appointment. And each week, hundreds of thousands of people across the state are getting their shots — in pharmacies and doctor’s offices, football stadiums and churches. 

Here, we break down some of the key information to know after you’re vaccinated.


How will I feel after my shot?

For a lot of people, the days after getting a vaccine are filled with excitement and relief — as well as some discomfort. The vaccines can prompt a few common side effects, which are generally a normal sign that your immune system is kicking into gear. 

The arm where you got the shot may be sore, red or swollen, according to the Centers for Disease Control and Prevention. And you may feel some flu-like symptoms, like fatigue, nausea, fever, chills, headache or muscle pain.

Reports so far have shown that these effects tend to show up more strongly in women, young people and those who have already recovered from COVID-19. And if you’re getting the Moderna or Pfizer vaccine, the second dose may kick off a stronger reaction, since your immune system is already primed to attack after the first shot.

These effects should go away within a few days, and some simple steps — like drinking lots of fluids, getting plenty of sleep and moving your arm around — can help you feel better. You can also take over-the-counter pain relievers after the shot, though you shouldn’t take them before your vaccine, doctors recommend.

Health officials are still keeping a close eye out for any other adverse reactions linked with the vaccines. 

On April 13, the CDC and FDA recommended a pause on giving out the Johnson & Johnson vaccine after several reports of blood clots in women who had gotten the shot. The conditions were very rare — six cases out of more than 6.8 million doses administered — but concerning. The Wisconsin Department of Health Services told all providers in the state to stop administering the J&J vaccine to wait for further review, out of what Secretary-designee Karen Timberlake called “an abundance of caution.”

For most people, the effects from the COVID-19 vaccine should go away within a few days. If you have an especially severe or long-lasting reaction after your shot, you should reach out to your doctor.


How soon will I be protected?

The CDC considers you to be “fully vaccinated” once you’ve waited two weeks after your last dose in the vaccine series. 

If you’re getting the Pfizer or Moderna vaccine, that means two weeks after your second shot. And if you’re getting the Johnson & Johnson vaccine, that’s two weeks after your one-and-done shot.

The limbo period is important because your body takes some time to build up its full immune response after getting the shot. 

Remember, the stuff that’s injected in the shot is not what actually protects you from the coronavirus, so you are not immune right after getting that jab. Your body uses the material from the shot to get its defense system ready and learn to recognize the virus.

As Katherine Wu describes it in The Atlantic, “the shot simply delivers a package of study materials to the body” — but the immune system needs time to cram before it’s ready to ace the final exam of fighting off a real virus.

You’ll still have some protection before you reach that two-week mark. A “real world” study of the Pfizer and Moderna vaccines found that infection rates dropped by around 80% in the waiting period between the two doses.

Still, to take advantage of the vaccines’ full protection — and avoid letting “cheat days” add fire to the virus’s continuing spread — a little more patience goes a long way.


What’s safe to do when I am fully vaccinated?

Once you have reached the fully vaccinated mark, the CDC says you’re OK to get back to some activities. But you still should be careful: No vaccine can offer perfect protection, and while research so far has been promising, we’re still learning about whether vaccinated people can transmit the virus to others.

Small, indoor gatherings are fine, even without wearing masks, as long as everyone in the group is fully vaccinated, according to CDC guidance. And you can also get together with one other household of unvaccinated people, as long as no one is at high risk of severe COVID-19 symptoms. 

When figuring out how risky an activity might be, it’s important to think about who you’re with, said Dr. Matt Anderson of UW Health. 

“Once you’re vaccinated, the things that you’re doing are by and large about protecting other people, or being respectful of other people around you,” Anderson said.

So, for example, the CDC says vaccinated grandparents can hang out with their unvaccinated grandkids, because both groups are at pretty low risk for a really bad COVID-19 case. But if a family member is still unvaccinated and has, say, a chronic condition, you may still want to keep your distance. 

This month, the CDC added that fully vaccinated people can travel in the U.S. without having to quarantine or get a coronavirus test. International travel is a bit more complicated: Fully vaccinated people should still test negative before returning to the U.S., and other requirements will depend on the country. 

Even when fully vaccinated, you should keep wearing a mask in public and avoid getting together in large groups, the CDC recommends.

It can be complicated to figure out the rules in a partially-vaccinated world. In the end, Anderson said, it’s all about figuring out that risk-benefit analysis, keeping in mind that your decisions also affect those around you.

“There’s, one: ‘What can I do if I’m protected?’” Anderson said. “And there’s, ‘What should I be doing as part of protecting other people, and helping to reduce spread in the areas where I’m at and the community where I’m at so we can get back to normal?’”


What do those efficacy rates actually mean?

For the vaccines rolling out in the U.S., the overall takeaway from the efficacy data is that these shots are very protective against COVID-19. The specific numbers are a bit more complicated.

Take the Pfizer vaccine, for example. In clinical trials, researchers found this vaccine to have an efficacy rate of around 95% — a really high level of protection.

Let’s start with what that number does NOT mean. It doesn’t mean that 95% of people who get the vaccine will be immune to COVID-19, while the other 5% will be left vulnerable. And it doesn’t mean that 95% of the time you bump into an infected person, you’ll be fine, but 5% of the time you’ll get sick. 

The efficacy rate can be tough to understand because it’s all relative, Anderson said. It measures the difference in case counts between the two groups in a clinical trial: The ones who got the real vaccine, and the ones who received a placebo shot. 

In the case of the Pfizer trials, there were 162 cases of COVID-19 in the placebo group, but only eight cases in the vaccinated group. So, the number of cases in the vaccinated group was 95% lower than the number of cases in the placebo group. Only around 0.04% of vaccinated volunteers actually had a case of COVID-19.

The measures of “effectiveness” that we are getting more details on now use the same kind of math — but they compare vaccinated people with unvaccinated people in the real world, as the shots move beyond the trial phase.

So what does that mean for you? Well, your own risk will be relative, too. It depends on how many infections are circulating in your community. It also depends on your own behavior and your own immune system.

But, specific numbers aside, the efficacy rates mean the vaccines do a great job at reducing infections, Anderson said. So-called “breakthrough cases,” where people still get infected after they are fully vaccinated, are quite rare and tend to be less severe.

“You have a really significantly reduced risk of getting COVID-19,” Anderson said. “And you have an even-more-than-that reduced risk of being hospitalized.”

And, as more and more people get vaccinated, we make it harder and harder for the virus to spread at all. So just as your vaccination shrinks your personal COVID-19 risk to an extremely low level, it also chips away at the risk for the whole community.


Why are cases still going up if more people are vaccinated?

Though the vaccines offer a lot of hope for the end of the pandemic, they aren’t a silver bullet. And Wisconsin, along with other parts of the world, has actually seen its COVID-19 infections rise in recent weeks, even with more than 3.5 million shots in arms across the state.

“It seems counterintuitive. At a time when vaccinations are available and everyone is aware of safe practices, we should see COVID-19 infection rates declining. That is not the case,” Milwaukee Health Commissioner Kirsten Johnson said in a statement as the city rolled back capacity limits last week.

The rising numbers don’t mean that our vaccines are not working. Actually, Anderson pointed out, infections among older Wisconsinites — who were the first to get their shots — have stayed “extremely low.” The latest cases in the Badger State have been concentrated among younger age groups, who still have lower rates of vaccination.

Coronavirus variants may be part of the explanation. Wisconsin has identified hundreds of cases of highly contagious variants, which have made up a growing share of sequenced samples in recent weeks, state epidemiologist Dr. Ryan Westergaard said at a briefing.

And plain old COVID fatigue may also be playing a role. After more than a year of precautions, and with vaccinations offering a welcome bit of optimism, it may be tempting to give ourselves a bit of a break.

But even as more than 35% of Wisconsinites have gotten at least one shot, that means the majority of residents have not. 

With a lot of people still vulnerable to COVID-19, and a lot of virus still making its way through the community, now is not the time to let down our guard, experts say — especially when we are on our way to the finish line.

“I so badly want to be done. I know you all so badly want to be done,” CDC Director Rochelle Walensky said at a press conference. “We are just almost there, but not quite yet. And so, I am asking you to just hold on a little bit longer, to get vaccinated when you can, so that all the people that we all love will still be here when this pandemic ends.”