How long is infectious mononucleosis (mono) contagious?

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From the Research

Mono is typically contagious for about 4-6 weeks after symptoms appear, but the virus can be shed in saliva for up to 18 months after infection. The most contagious period is usually during the acute phase when symptoms like fever, sore throat, and fatigue are present. Mono, caused by the Epstein-Barr virus (EBV), spreads primarily through saliva exchange, earning its nickname "the kissing disease" 1. There is no specific medication to shorten the contagious period, as antiviral drugs are not effective against EBV. To prevent spreading mono, avoid kissing, sharing drinks or utensils, and maintain good hygiene practices like handwashing. Even after symptoms resolve, remember that you may still be contagious, so continue these precautions for several weeks. The virus remains dormant in your body after recovery but rarely causes symptoms again, though you may occasionally shed the virus in your saliva throughout your life.

Some key points to consider:

  • The virus can be shed in saliva for an extended period, even after symptoms have resolved 2
  • Corticosteroids may be used in certain cases, such as impending airway obstruction, but their use is not recommended for common symptoms of mono 3
  • Good hygiene practices, such as handwashing, can help prevent the spread of mono
  • The virus can remain dormant in the body after recovery, but rarely causes symptoms again 1

It's essential to note that the contagious period can vary from person to person, and the risk of transmission is highest during the acute phase of the illness. By taking precautions and maintaining good hygiene practices, you can reduce the risk of spreading mono to others. Additionally, while corticosteroids may be used in certain cases, their use is not recommended for common symptoms of mono, and antiviral drugs are not effective against EBV 4, 5.

References

Research

Infectious Mononucleosis.

Current topics in microbiology and immunology, 2015

Research

Corticosteroids for infectious mononucleosis.

Canadian family physician Medecin de famille canadien, 2023

Research

Steroids for symptom control in infectious mononucleosis.

The Cochrane database of systematic reviews, 2015

Research

Infectious mononucleosis and corticosteroids: management practices and outcomes.

Archives of otolaryngology--head & neck surgery, 2005

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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