Can You Get Mono and Strep at the Same Time?

When kids get sick, pediatricians usually like to diagnose them with one single thing, so they usually wouldn't diagnose strep and mono at the same time.

A doctor checking a child's throat
Tom Merton / Getty Images 

Both strep throat and mono do have similar symptoms, including a sore throat, fever, and swollen glands.

In most cases, though, mono is suspected in a child who tests negative for strep but has persistent symptoms.

Strep vs. Mono Tests

Tests can be done to evaluate a child for each infection, including:

Strep Test
Mono Test

  • A heterophil antibody test (monospot) and Epstein-Barr virus (EBV) titer levels for mononucleosis

They aren't usually all done at the same time, though, especially at the first sign that a child has a sore throat and fever.

Instead, a child who has already had a negative strep test returns to their pediatrician four or five days later because he isn't getting better, and is then tested for mono.

Or a child who tested positive for strep is put on an antibiotic, such as amoxicillin, and develops a bad rash a few days later, which is characteristic of mono. But even if a child with strep doesn't get a rash, he may just not get better, and still, get tested for mono.

So it is possible to have strep and mono at the same time, although one doesn't necessarily cause the other. The more common scenario is that a child got infected with both by chance. The incubation period is four to seven weeks for mono and two to five days for strep, so your child would have had to be around someone with mono and strep at the right times, got infected, and then show symptoms of both infections at the same time.

Or it is possible that one or both of the tests were a false positive. A CDC investigation of a higher than normal number of strep throat cases at a clinic in Wyoming recently found that incorrect technique likely caused many strep throat tests to be falsely positive (they waited too long to read the tests).

Still, some experts do believe that you can have both strep and mono at the same time because these infections have a 'synergistic effect' on a child's inflamed throat and tonsils, for example, making it more likely that you could become infected with mono while having strep. But while older studies found that 30 percent of patients with mono also had strep, some newer studies have found rates that were much lower, at only three or four percent.

Although it is sometimes hard to tell if a child has mono and strep when both tests are positive, or if he has mono and is a strep carrier, if he tests positive for strep, he will need antibiotics to prevent getting rheumatic fever. And since he has mono, this is one of the few situations in which it is important that your pediatrician carefully chooses which antibiotic to prescribe to your child. This is because amoxicillin or Amoxil, the antibiotic that is often used to treat kids with strep, can cause a bad rash if you take it when you have mono.​

Strep Carriers

A more likely scenario is that a child with mono and strep is just a strep carrier. These are kids who had a strep throat infection and even though they are better and have no strep symptoms, the strep bacteria continue to live in the back of their throat.

Strep carriers are not thought to be contagious and they can test positive for strep for months or years, even when they have a sore throat that is being caused by a virus.

5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Mononucleosis. TeensHealth from Nemours.

  2. Infection Exposure Questions. Schmitt Pediatric Guidelines LLC. in Seattle Children’s.

  3. Notes from the Field: Group A Streptococcal Pharyngitis Misdiagnoses at a Rural Urgent-Care Clinic — Wyoming, March 2015. Morbidity and Mortality Weekly Report (MMWR) Centers for Disease Control and Prevention. MMWR. 64(50);1383-5

  4. Highlights Of Prescribing Information. US Food & Drug Administration.

  5. Demuri GP, Wald ER. The Group A Streptococcal Carrier State Reviewed: Still an Enigma. J Pediatric Infect Dis Soc. 2014;3(4):336-42.  doi:10.1093/jpids/piu030

Additional Reading

By Vincent Iannelli, MD
 Vincent Iannelli, MD, is a board-certified pediatrician and fellow of the American Academy of Pediatrics. Dr. Iannelli has cared for children for more than 20 years.