Strep throat circulates every year in the United States, and cases reliably spike between December and April. If it feels like strep is everywhere right now, that tracks with the bacteria’s normal seasonal pattern. Preliminary 2023 data from the CDC showed serious strep infections hit a 20-year high, and since 2022 the seasonal cycle of Group A Strep activity has returned to its pre-pandemic rhythm, meaning winter and spring surges are very much in play.
When Strep Season Peaks
Group A Streptococcus bacteria circulate year-round, but winter and spring are the high season. A large multicenter study covering 2010 through 2019 found that strep throat incidence in children peaked in winter at roughly 4 cases per 1,000 patients and stayed elevated through spring at about 3.4 per 1,000. In summer, that number dropped to 1.8 per 1,000 before climbing again in fall. Adults followed the same curve at lower rates, peaking around 0.32 per 1,000 in winter.
The practical takeaway: if you’re reading this between December and April, strep is almost certainly circulating in your area. Kids in school and daycare settings drive much of the spread, so parents tend to notice waves of cases moving through classrooms during these months.
How Strep Spreads
Strep passes from person to person through respiratory droplets, the tiny particles released when someone coughs, sneezes, or talks. It can also spread by sharing cups, utensils, or food with an infected person. After exposure, symptoms typically appear within two to five days.
A person with untreated strep throat is contagious the entire time they have symptoms. Once antibiotics are started, that window closes quickly. You’re generally no longer contagious within 12 hours of your first dose, which is why schools and daycares typically require kids to stay home until they’ve been on antibiotics for at least 12 hours.
How to Tell Strep From a Regular Sore Throat
Most sore throats are caused by viruses, not bacteria, so not every scratchy throat during cold season is strep. Doctors look for a specific cluster of signs to decide whether testing is warranted. The key features that point toward strep rather than a virus are:
- Fever of 100.4°F (38°C) or higher
- No cough (cough suggests a viral cause)
- Swollen, tender lymph nodes in the front of the neck
- White patches or swelling on the tonsils
The more of these you have, the more likely strep becomes. But even with all four, a rapid strep test or throat culture is needed to confirm the diagnosis. The absence of cough is one of the most useful clues: if you’re coughing, sneezing, and have a runny nose, a virus is the far more likely culprit.
What Treatment Looks Like
Strep throat is treated with antibiotics, typically for 10 days. Amoxicillin and penicillin are the standard first choices because they’re effective, inexpensive, and cause fewer side effects than broader alternatives. If you have a penicillin allergy, your doctor will choose from several other options, some of which run for 10 days and one that takes just 5 days.
Most people start feeling better within a day or two of starting antibiotics, but finishing the full course matters. Stopping early can leave bacteria behind, increasing the chance of complications like rheumatic fever or kidney inflammation. These complications are rare when strep is properly treated, but they’re the main reason antibiotics are recommended rather than just waiting it out.
Keeping It From Spreading at Home
When someone in your household has strep, a few straightforward steps reduce the odds of it jumping to everyone else. Wash hands frequently with soap and water, especially after contact with the sick person. Don’t share cups, utensils, water bottles, or bites of food. Any dishes or linens used by the infected person are safe for others once they’ve been washed normally, so no special sanitizing is needed.
Have the sick person cover coughs and sneezes, and keep some distance during the first 12 hours of antibiotic treatment, when they’re still contagious. Young children in particular can reinfect each other quickly in close quarters, so keeping siblings separated during that initial window helps.
Why Recent Years Have Seen More Cases
The post-pandemic years brought a noticeable rebound in strep activity. During 2020 and 2021, social distancing and masking suppressed transmission of many respiratory pathogens, including Group A Strep. When those measures lifted, many children had less accumulated immunity than usual, and cases surged. By 2023, preliminary CDC data showed serious invasive strep infections reaching levels not seen in two decades. The seasonal pattern has since stabilized, but the overall number of infections remains elevated compared to pre-2020 baselines.
This doesn’t mean strep has become more dangerous on a case-by-case basis. The vast majority of infections are still straightforward sore throats that resolve completely with antibiotics. The rise in severe cases reflects higher overall circulation of the bacteria rather than a new, more virulent strain.