Mpox Virus Information and Resources

There is currently an outbreak of mpox (a viral infection caused by the monkeypox virus) in countries where spread of this virus is atypical. While mpox case numbers have decreased in both New York State and New York City, the Student Health Center continues to monitor the situation closely.

Need Testing? 

MPV Vaccine (JYNNEOS) can be accessed at Mount Sinai Hospital or via the NYC Department of Health and Mental Health.

For answers to frequently cited concerns surrounding mpox, including in-depth information on symptoms, transmission, and treatment, please refer to the Medical School’s Mpox FAQs (updated December 2022).

The most common symptom is a rash or sores that can look like pimples or blisters.  Sores can spread over the whole body OR localize to certain areas (e.g., the face, hands, or feet, or around or inside the mouth, genitals, or anus). The rash can be itchy or painful.

Some people also have flu-like symptoms (such as fever, swollen lymph nodes, headache, and fatigue).  These may start either before, at the onset of, or after the rash appears.

Symptoms typically start 3 to 17 days after exposure.  People are contagious when they have active sores, and remain contagious until all sores have healed and a new layer of skin has formed. Generally, this takes two to four weeks.

Mpox is primarily transmitted via direct contact with the lesions or body fluids of an infected person. Most transmission occurs through intimate contact including:

  • Oral, anal, or vaginal sex or touching of the genitals or anus of a person with mpox
  • Hugging, massaging, or kissing
  • Prolonged face-to-face contact
  • Contact with fabrics or objects that were used by a person with mpox and have not been disinfected (e.g., bedding, towels, fetish gear, sex toys)

The current mpox outbreak has affected some populations more than others.  In addition, the risk of getting mpox is higher among people who engage in certain activities or have certain health conditions.  The best forms of treatment are prevention and vaccination. The NYC DOHMH is promoting these risk mitigation strategies.

At this time the following people are prioritized for vaccination:

  • People who know or suspect that they may have been exposed to mpox in the past 14 days
  • People who have or may have multiple or anonymous sex partners, or participate or may participate in group sex
  • People whose sex partners are eligible for vaccine
  • Anyone else who considers themselves to be at risk for mpox through sex or other intimate contact

Patients who have had mpox likely have some protection and are currently not eligible to get a dose of the vaccine.

You can find more information about vaccine eligibility and recommendations on the NYC DOHMH website. This site is updated regularly.

The vaccine for mpox and smallpox is called JYNNEOS. Per current guidelines, all JYNNEOS vaccines are given intradermally unless an individual has a contraindication (e.g., age <18 or history of keloid scarring).

For eligible individuals:

Please contact Student Health Services if you are eligible for a vaccine and are having difficulty finding an appointment.

You can get the JYNNEOS vaccine at the same time as most vaccines including the flu, human papilloma virus (HPV), hepatitis A, hepatitis B, meningococcal, and herpes zoster (shingles) vaccines. 

You can also get the JYNNEOS vaccine before, after, or at the same time as the COVID-19 vaccine. However, people at increased risk of myocarditis (inflammation of the heart), particularly males ages 12 to 39, should consider waiting four weeks between getting the JYNNEOS and COVID-19 vaccines. This is because there is a rare risk of developing myocarditis after COVID-19 vaccination. JYNNEOS clinical trials did not show an increased risk of myocarditis following vaccination.

If you know you were exposed to mpox, you should not delay getting the JYNNEOS vaccine, even if you recently got a COVID-19 vaccine.

For others, in deciding whether to delay getting either vaccine, consider your risk of exposure and risk of severe illness from COVID-19 and mpox. Talk to your health care provider if you have questions about timing of vaccination.

Are There Side Effects of the Vaccine?
Common side effects of the JYNNEOS vaccine include:

  • Fatigue
  • Headache
  • Muscle pain
  • Redness, swelling, soreness, and itchiness at the site of injection.

Generally, the injection-site side effects from an intradermal injection are worse and last longer than those from a subcutaneous injection. Intradermal injections can result in long-term or permanent scarring, discoloration and thinning of the skin at the injection site. The risk for these types of reactions is higher for people with darker skin. People will be asked at the vaccination site whether they have a history of keloid scars, and those who do will be offered subcutaneous administration.