Mpox (monkeypox): symptoms, transmission and vaccination

What is mpox?

Mpox (formerly “monkeypox”) is a viral disease related to smallpox, usually less severe. In 2022 a global outbreak mainly affected networks of men who have sex with men: in France, 4,975 cases were reported in 2022, over 95% of them among MSM (Santé publique France). The virus still circulates, and WHO is also monitoring a variant (clade Ib) that emerged in Central Africa.

What are the symptoms?

According to WHO they usually appear within a week, but 1 to 21 days after exposure:

• a rash of spots or lesions going through several stages (flat spots, blisters, pustules, scabs), on the genitals, anus, mouth, face, hands;
• fever, headache, muscle aches, back pain, extreme tiredness;
• swollen glands;
• sometimes sore throat, proctitis (intense anal pain), burning when peeing.

Lesions last 2 to 4 weeks. They can be very painful, especially in the anus or throat.

How is it transmitted?

WHO lists:

• close skin-to-skin or mouth-to-skin contact, including sex;
• respiratory droplets during prolonged face-to-face contact;
• contaminated objects: sheets, towels, clothes, sex toys.

Condoms aren’t enough, since lesions can be anywhere on the skin.

What should I do if I think I have it?

1. See a doctor (GP, sexual health clinic), calling ahead: a swab of a lesion confirms the diagnosis.
2. Self-isolate until lesions have fully healed (scabs fallen off), don’t pop blisters, cover lesions, wear a mask around others.
3. No sex while ill; WHO advises condoms for 12 weeks after recovery.
4. Tell your partners: quick vaccination after contact can limit the disease.

Vaccination

According to Sexosafe (Santé publique France):

• who: men who have sex with men and trans people with several partners, sex workers, people working in sex-on-premises venues, and their household members;
• no proof of anything is required;
• schedule: 2 doses 28 days apart if you were never vaccinated against smallpox, then a booster after at least 2 years; 1 dose if you had a smallpox vaccine before 1980; 3 doses if you are immunocompromised;
• no vaccine needed if you’ve had mpox since 2022;
• it is a live non-replicating vaccine, with no mRNA;
• estimated effectiveness of 66 to 90% after two doses. Protection is not immediate.

In France, vaccination sites are listed on sante.fr, and many CeGIDD clinics vaccinate.

In short

A rash, painful anal lesions or fever after a hookup: see a doctor and avoid contact. And if you have several partners, get your two doses: it’s free.