MRSA in the Mouth: Signs, Causes, and Treatment

MRSA in the Mouth: Signs, Causes, and Treatment
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MRSA in the Mouth: Signs, Causes, and TreatmentClinical Content Reviewed by Dr. Jay Khorsandi, DDS
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Table of Contents

  1. Symptoms
  2. Complications
  3. Causes
  4. Is MRSA Contagious?
  5. Transmission
  6. Risk Factors
  7. Treatment
  8. Prevention
  9. Frequently Asked Questions
  10. References

MRSA, or methicillin-resistant Staphylococcus aureus, is an infection caused by a staph bacteria that is resistant to most antibiotics. It is typically found in people who have spent time in a hospital or some other healthcare facility.

Recent reports are showing higher numbers of MRSA rates in the mouth. There is no concrete reason for why, but it could be because of a wide usage of antibiotic prophylaxis in at-risk dental procedures.

The mouth holds a large number of micro-organisms, that can be part of a repository of antibiotic-resistant factors. In the mouth, bacteria form an enclosed community in a self-produced pattern. This pattern makes it easier for antibiotic resistance genes to accomplish horizontal gene transfer.

Symptoms of MRSA

Typically, a staph infection is easily treated, but if it spreads to deeper tissue or blood, it can be life-threatening. The symptoms of an oral staph infection, MRSA include:

  • Inflammation at both or one of the corners of the mouth
  • Burning or painful sensation in the mouth
  • Swelling or redness inside the mouth

The MRSA has also been reported to develop around a tooth. If this occurs, the symptoms will include:

  • Fever
  • Sensitivity to pressure or temperature
  • Swelling, redness, or pain around the affected tooth
  • Bad smell or taste in the mouth
  • Swelling in the face or cheeks

Complications of Staph in Your Mouth

Doctors and hospitals can easily treat several types of staph infections, but at times serious complications can occur.

In these cases, staph bacteria spread from the site where the infection started into the bloodstream.

This condition is serious and known as bacteremia. Symptoms of bacteremia include:

  • Low blood pressure
  • Fever

Left untreated, bacteremia can develop into septic shock, or sepsis. Septic shock occurs when your body reacts strongly to an infection. The reaction creates drastic changes in your body and can be potentially life-threatening. Sepsis is mainly caused by bacterial infections, but any infection can cause this condition if left untreated.

Because MRSA infections are so resistant to antibiotics, they are difficult to treat. Because of this difficulty, the infection can spread and affect your:

  • Joints
  • Bloodstream
  • Bones
  • Lungs
  • Heart

Causes of MRSA in the Mouth

Staph infections are usually found in your nose or on your skin. Bacteria are typically harmless unless it enters your body through a wound or cut.

Even if they enter through a skin breakage, they are typically only a minor skin problem if you are healthy.

MRSA in the mouth is considered to be the result of unnecessary antibiotic use. Antibiotics have been getting prescribed for viral infections, cases of flu and colds that will not respond to them.

When antibiotics are not used correctly, they contribute to the increase of drug-resistance bacteria. Bacteria live on a fast track, and if germs survive treatments with one antibiotic, they will soon learn how to resist others.

Is MRSA Contagious?

MRSA spreads through contact, so you can contract it by touching someone who has it. You can also contract MRSA by touching objects that have bacteria on them.

MRSA in your mouth will also affect your saliva. There are plenty of means of transmitting certain illnesses through your saliva. These are a few of the illnesses that can work their way from your saliva into your nose, lungs, throat and spread to others:

  • Strep bacteria
  • Colds
  • Mono
  • Cold sores
  • Flu virus
  • Hepatitis C and B
  • Cytomegalovirus

Anyone with MRSA in their mouth can spread the infection to others by talking or coughing. It can also be transmitted through a contaminated surface, object or by touching your mouth or face.

How Can MRSA be Transmitted in a Dental Setting?

An active MRSA infection typically involves patients who are not healthy or have a medical condition making them weak. MRSA occupies those who remain asymptomatic and are carriers of the infection. Healthy, young people and dental personnel typically become passive MRSA carriers.

The most common transfer of the infection can occur if the dental personnel carry MRSA from one patient to another on their unchanged gloves, hands, under their fingernails, or hands.

The least common or secondary transmission of the infection is through environmental objects. Indirect contact by contaminated equipment in the treatment area, such as the dental chair, the floor beneath the chair, towel dispenser, sink, and other surfaces in the dental office are also sources of transmitting the infection.

An unfortunate factor surrounding MRSA is that it can survive on object surfaces and instruments for two to three days and the personnel's hands for up to three hours.

Risk Factors of MRSA

Risk factors of MRSA include significant mortality and morbidity for patients who are elderly or have compromised immune systems. It is much less serious and seldom fatal in younger patients.

Researchers recommend health care workers who carry the MRSA organisms limit or eliminate direct contact with patients until they are cleared of the organisms. Exposure risks and medical concerns for contracting MRSA infections include:

  • Having a history of MRSA infection
  • Having a history in the past year of healthcare contact
  • Frequent or recent antibiotic use
  • Close contact with an infected person who has MRSA
  • Injection drug use
  • Recurrent skin disease
  • Living in crowded conditions
  • Incarceration
  • Being involved in sports with skin-to-skin contact

Treatment for MRSA

If you develop redness, swelling, or pain in your mouth that becomes a concern, you should see your doctor. It is important to learn what the cause of your symptoms is so an appropriate course of treatment can begin.

Some staph infections will respond to antibiotic treatments and other treatments that are more resistant to antibiotics may need a stronger regime. Some infections will require treatment through an IV. Your doctor will determine the type of your infection, so the proper treatment is started as early as possible.

Prevention of MRSA

In a hospital setting, people with MRSA are often isolated as a means to prevent the spread of the infection. Health care workers and visitors of those in isolation may be required to wear protective garments.

Healthcare workers need to follow strict hand hygiene procedures. Healthcare and dental workers can help prevent MRSA by washing their hands or using hand sanitizer before and after each appointment.

Frequently Asked Questions

Can you get MRSA in your mouth?
Yes, MRSA in the mouth is enhanced with the wide use of antibiotic prophylaxis during at-risk dental procedures. This infection can also be a threat to your mouth if dental care workers do not properly clean their equipment, hands, or surface areas in the office.
What are the first signs of MRSA?

Symptoms of MRSA include:

  • Inflammation at both or one of the corners of the mouth
  • Burning or painful sensation in the mouth
  • Swelling or redness inside the mouth
Can dental abscesses be MRSA?
MRSA can cause a boil or abscess. It will begin as a small bump that looks much like a pimple, and quickly turns painful, hard, filled with pus or a cluster of blisters. Not all abscesses or boils are MRSA bacteria, there are reasons for these culprits.


MRSA infection. (1998-2022) Mayo Clinic – Patient Care & Health Information.

Methicillin-Resistant Staphylococcus aureus in the Oral Cavity: Implications for Antibiotic Prophylaxis and Surveillance. (December 2020). Eric S Donkor and Fleischer CN Kotey, U.S. National Library of Medicine-National Institutes of Health.

What Does an Oral Staph Infection Look Like, and How Do I Treat It? (September 2019). Healthline.

Septic Shock. (October 2021). Healthline.

Understanding MRSA Infection—the basics. (April 2021). WebMD.

Does Saliva Have Health Risks? 3 Ways Germs Can Spread. (April 2020). Cleveland Clinic.

Management of MRSA patients on the dental chair (August 5, 2017). International Journal of Research in Medical Sciences-Case Report.

Disclaimer: This article is intended to promote understanding of and knowledge about general oral health topics. It is not intended to serve as dental or other professional health advice and is not intended to be used for diagnosis or treatment of any condition or symptom. You should consult a dentist or other qualified healthcare provider with any questions you may have regarding a medical condition or treatment.