If you wake up feeling sick on the day of your vaccine appointment, you may need to cancel—even if you think it’s just a cold. Amesh A. Adalja, MD, an infectious disease expert and senior scholar at the Johns Hopkins Center for Health Security, told Prevention that upper respiratory symptoms are particularly concerning because while they may seem like a cold, it could actually be the coronavirus instead. “There aren’t very many colds circulating right now,” he explained. According to the Healthline, both COVID and the common cold can produce upper respiratory symptoms such as stuffy nose and sore throat. And for more advice on getting vaccinated, discover The Only Medication You Should Take Before Your COVID Vaccine, Experts Say. The Centers for Disease Control and Prevention (CDC) recommends that you do not get vaccinated if you are infected with COVID. “People with COVID-19 who have symptoms should wait to be vaccinated until they have recovered from their illness and have met the criteria for discontinuing isolation,” the CDC says. The agency adds that this guidance applies to those who get COVID before their first vaccine appointment and those who get the virus between doses. Per the CDC, you can discontinue isolation if it has been at least 10 days since the onset of your symptoms, at least 24 hours since your fever stopped without the use of fever-reducing medications, and your other symptoms have improved. And for more CDC guidelines you need to know, The CDC Says Don’t Do This Until 4 Weeks After Getting Vaccinated. Even if you don’t have COVID and really just do have a cold, there may be another reason you’ll want to postpone your appointment. As many vaccine recipients have already found out, post-shot side effects can be somewhat unpleasant. The CDC says people can experience a variety of vaccine reactions from the COVID shot, including fatigue, headache, muscle pain, chills, fever, and nausea. People who are already feeling sick could just end up exacerbating their symptoms by getting vaccinated. “If you have a stuffy nose and are feeling crummy, the vaccine could make you feel even crummier,” William Schaffner, MD, an infectious disease specialist and professor at the Vanderbilt University School of Medicine, told Prevention. And for more useful information delivered straight to your inbox, sign up for our daily newsletter. Postponing your appointment does not you should forgo vaccination altogether—whether you’re getting the first or second dose. If you’ve only had your first shot and get sick before your second, you can delay your appointment and still get it in accordance with CDC guidelines. According to the agency, your second dose may be given up to six weeks or 42 days after the first dose, if necessary. If you do not get your second dose for a two-dose vaccine process, you are not considered fully vaccinated, per the CDC. “We often say that a dose deferred is a dose never received,” Schaffner told Prevention. “Don’t let that happen to you.” And for more on life after vaccination, The CDC Says People Who Get COVID After Vaccination Have This in Common.ae0fcc31ae342fd3a1346ebb1f342fcb