CLOSE-CONTACT VIRAL INFECTION / CARE & TRANSMISSION
Monkeypox virus (MPXV)
Mpox can spread through close skin or mucosal contact, including sex, and through contaminated materials. Condoms do not cover all relevant contact. Vaccination, and having a new rash checked early, are the most useful steps. [51][52][53]
Transmission risk
Risk by type of contact
Bottom line. Mpox spreads through intimate skin and mucosal contact, including kissing, so condoms cannot cover every route. Sexual-contact attack rates and vaccine effectiveness are useful evidence, but neither supplies a single per-act risk.
General
Oral
Vaginal
Anal
Kissing
What changes the risk (3)
- JYNNEOS vaccination: retain study differences. MEDIUM per study: two-dose adjusted effectiveness was 85.9% (95% CI 73.8-92.4) in Dalton 2023 and 66.0% (47.4-78.1) in Deputy 2023. One-dose estimates were 75.2% (61.2-84.2) and 35.8% (22.1-47.1), respectively. Different populations/designs; not per-act effects. Sources 5, 6
- Clade developments since 2023. LOW for a numeric adjustment: clade Ib has spread internationally and through sexual networks. The small clade Ib contact series is not proof of a fixed increase over clade IIb; vaccine/route estimates cannot automatically be transferred unchanged. Sources 7, 2
- Lesions, other close contact and illness. LOW for exact modifiers: uncovered skin, oral lesions and shared contaminated materials can maintain exposure despite a condom. No validated ejaculation or menstruation multiplier. Sources 3
Condoms and dental dams
No validated mpox-specific condom/dam efficacy percentage. A 2024 case-control association for condomless receptive anal sex compares heterogeneous contact patterns, not randomized or otherwise clean protected versus unprotected anal acts. Evidence: Low Sources 4, 3
Sources for this risk profile (7)
- El-Saed A et al. BMC Infectious Diseases, 2026. Secondary attack rates after mpox exposure in multiple settings during the 2022-2024 pandemic: a systematic review. DOI: 10.1186/s12879-026-13410-7. link.springer.com
- Laurenson-Schafer H et al. Emerging Infectious Diseases, 2026. Characteristics and Transmission Dynamics of Global Travel-Related Mpox Cases Caused by Clade Ib Monkeypox Virus. DOI: 10.3201/eid3202.251530. wwwnc.cdc.gov
- WHO WHO, 2024. Mpox: questions and answers. who.int
- CDC MMWR, 2024. Risk of Clade II Mpox Associated with Intimate and Nonintimate Close Contact Among Men Who Have Sex with Men and Transgender Adults - United States, August 2022-July 2023. DOI: 10.15585/mmwr.mm7340a2. cdc.gov
- Dalton AF et al.; CDC MMWR, 2023. Estimated Effectiveness of JYNNEOS Vaccine in Preventing Mpox: A Multijurisdictional Case-Control Study - United States, August 19, 2022-March 31, 2023. DOI: 10.15585/mmwr.mm7220a3. cdc.gov
- Deputy NP et al. New England Journal of Medicine, 2023. Vaccine Effectiveness of JYNNEOS against Mpox Disease in the United States. DOI: 10.1056/NEJMoa2215201. pubmed.ncbi.nlm.nih.gov
- WHO Disease Outbreak News, 2025. Mpox: multi-country external developments. who.int
* How to read these figures. Each is a published estimate under the conditions shown beside it, usually an untreated partner and a single act or partnership. It is not a prediction of your personal risk.
- Evidence: High
- Several prospective studies or a systematic review broadly agree.
- Evidence: Medium
- One or two studies, wide uncertainty, or a model.
- Evidence: Low
- Guideline judgment, case reports, or extrapolation.
Where no risk level is shown, the evidence cannot rank it. That is not the same as low.
Evidence reviewed through 2026-10-27. For reference only; not medical advice.
When to test after a possible exposure
Sample a suspicious rash/lesion when present; there is no validated routine asymptomatic post-exposure clearance test.
When to be seen sooner. Known close exposure or new compatible lesions warrant timely clinical/public-health contact rather than waiting for an arbitrary swab date.
-
MPXV / orthopoxvirus PCR
Testing is triggered by compatible clinical findings, not a fixed post-contact day.
If sores or other symptoms appear, get them checked; people with a known exposure can ask separately about vaccination.
Specimens: Lesion-surface material, exudate or crust; other specimens only when clinically indicated
Sources 1, 2
Early negatives, after treatment, and screening limits
An early negative result. A negative test from an unsuitable specimen or without an appropriate clinical target is not an all-clear result for the exposure.
After treatment. A repeat PCR is not automatically a test of infectiousness; clinical and public-health criteria govern follow-up.
Screening limits. CDC public guidance recommends testing for a compatible rash. The laboratory turnaround time is not an infection detection window.
Kissing and body sites. After kissing, oral or skin lesions can need assessment. A standard STI urine/blood panel does not test for mpox.
Treatment
Pain control, hydration and lesion care are important. Severe illness or major immune suppression needs specialist assessment. Randomized trial evidence has not shown faster clinical recovery with tecovirimat in uncomplicated study populations, so it should not be presented as a routine proven cure for everyone. [55][67]
Actions
1. Act on a recent exposure. Discuss vaccination as soon as possible, ideally within four days; administration through day 14 may still help. A standard JYNNEOS series has two doses 28 days apart, with strongest protection about two weeks after dose two. [53]
2. Test sores, not a routine panel. A new unexplained rash, rectal pain or other compatible symptoms are reasons to be seen; testing usually uses material from a sore. Until then, avoid close contact. Eye symptoms, severe pain or major immune suppression call for prompt care. [56][67]
3. Tell contacts and watch for symptoms. Public health can help tell recent sexual and close contacts, including people in contact before symptoms began. After an exposure, watch for symptoms for 21 days. With infection, avoid intimate contact until all sores have healed and new skin has formed. [52][56]
SCIENCE & CONTEXT
Mpox / the evidence
History
The virus was first identified in research monkeys in 1958, and the first recognized human case was reported in 1970. These dates do not establish the animal reservoir or evolutionary origin. The large multinational outbreak in 2022 expanded attention to sexual-contact transmission and to vaccination outside previously endemic settings. [51]
Impact
Mpox is an orthopoxvirus infection. It can cause fever, swollen glands, skin or mucosal sores, and sometimes marked genital or rectal pain; a few sores can still be mpox. Most cases resolve on their own. Severe illness is uncommon and more likely with major immune suppression, and eye involvement needs prompt care to protect vision. [56][67]
The amount of circulating infection changes with place, outbreak phase and vaccination. A fixed global prevalence assigned to all party attendees would become misleading quickly. Vaccine effectiveness estimates also vary across studies and populations; two doses provide better protection than one. [53][54]
Probability at a glance
| Vaccine status | Effectiveness | 95% confidence interval |
|---|---|---|
One dose | 75.2% | 61.2-84.2% |
Two doses | 85.9% | 73.8-92.4% |
Adjusted effectiveness against diagnosed mpox in one 12-jurisdiction US case-control study, 2022-2023. These are relative reductions versus unvaccinated participants, not absolute acquisition probabilities. [54]
In short: vaccination and local outbreak advice help most. Even with an intact condom, a new sore or a known close contact is worth having checked.