Monkeypox;  Case reference number US-BN-2023-000784 is a literature case report, title as stated above, identified on 25-Apr-2023 and concerns an adult male patient, 12th out of 15 (median age 29-35.5 years).  The aim of the article was to describe an investigation of monkeypox outbreak after a lesbian gay bisexual transgender queer (LGBTQ) event in 2022. The Department of Public Health (DPH) investigated monkeypox outbreak associated with festival. The patients that attended the festival on an unspecified date in August, reported as 6-7, were defined as persons with positive monkeypox or orthopoxvirus test results and had symptoms within 21 days before or after attendance (from 16-Jul-2022 to 28-Aug-2022). The patients were categorized by vaccination status at the time of festival. Forty event-associated patients from and other jurisdictions who attended festival were identified and had symptom onset occurring before festival. Most of the patients were (45 percent), male at birth (98 percent) and most of them reported having sex with men (70 percent). Two patients, of which one was living with human immunodeficiency virus (HIV), were hospitalized due to monkeypox.   On an unspecified date, reported as before festival, 15 (38 percent) case patients were vaccinated with a dose of Jynneos vaccine (batch number: unknown), at an unknown dose, route and site of administration, for an unknown indication.   None of the patients received two doses or were due for their second dose before festival and eight were vaccinated in less than 14 days before symptom onset. Median time from vaccination to symptom onset was 13 days.   More than one third of case-patients reported one vaccine dose before festival. Symptoms developed within 14 days after the first dose for eight patients (53 percent), who were partially vaccinated before festival.  Most of the patients (80 percent) had sexual activity during the probable exposure period of 21 days before symptom onset and some included sexual activity during festival, including three with symptom onset before festival. The patients that reported sexual activity during festival had a median of 3.5 partners and more had anonymous sex partners (50 percent) than casual or main partners (29 percent). More patients who received a dose of Jynneos vaccine before festival had sex with an anonymous partner during festival (27 percent) than did unvaccinated case-patients (12 percent). Among all patients, more patients unvaccinated before festival abstained from sex during festival (28 percent) than did vaccinated patients (13 percent). Seven (78 percent) of nine patients who abstained from sex during festival reported having sex during the probable exposure period. More than 50 percent of patients reported sex related to the event. Although equal proportions of vaccinated and unvaccinated patients reported sex during festival, vaccinated patients reported taking fewer precautions, such as abstaining from sex or avoiding anonymous sex.  The reporter did not provide the seriousness or causality assessment of the event 'monkeypox'. Additionally, the event of 'monkeypox' was assessed as serious due to medical significance.  No further information provided.  This case is linked to cases US-BN-2023-000744, US-BN-2023-000774, US-BN-2023-000775, US-BN-2023-000776, US-BN-2023-000777, US-BN-2023-000778, US-BN-2023-000779, US-BN-2023-000780, US-BN-2023-000781, US-BN-2023-000782, US-BN-2023-000783, US-BN-2023-000785, US-BN-2023-000786 and US-BN-2023-000787 (same reporter).; Reporter's Comments: This literature case report concerns an adult male patient, (12th out of 15) who experienced monkeypox, unknown time after he was vaccinated with a dose of Jynneos vaccine, at unknown dose, route and site of administration, for unknown indication. Monkeypox is unlisted and unexpected according to insert for Jynneos. The outcome was unknown. Medical history and concomitantly used medications for this particular patient were unknown. Considering that Jynneos is a non-replicating vaccine which does not contain the monkeypox, the event is assessed as not related to Jynneos. According to the insert for MVA-BN, vaccination with the product may not result in protection in all cases (as with any other vaccine). The case is serious due to its medical significance.; Sender's Comments: This literature case report concerns an adult male patient, (12th out of 15) who experienced monkeypox, unknown time after he was vaccinated with a dose of Jynneos vaccine, at unknown dose, route and site of administration, for unknown indication. Monkeypox is unlisted and unexpected according to insert for Jynneos. The outcome was unknown. Medical history and concomitantly used medications for this particular patient were unknown. Considering that Jynneos is a non-replicating vaccine which does not contain the monkeypox, the event is assessed as not related to Jynneos. According to the insert for MVA-BN, vaccination with the product may not result in protection in all cases (as with any other vaccine). The case is serious due to its medical significance.