Monkeypox virus infection in humans in 16 countries: April-June 2022

people with infection

Table 1. Table 1. Demographic and Clinical Characteristics of People with Monkeypox.

This series includes a total of 528 confirmed cases of monkeypox in humans from five continents, 16 countries and 43 clinical centers (Figure 1). The demographic and clinical characteristics of people with infection are summarized in Table 1.

Table 2. Table 2. Demographic and clinical characteristics of people with HIV infection in the case series.

Overall, 98% of those infected were gay or bisexual men, and 75% were white. The median age was 38 years. A total of 41% of people were living with HIV infection, and in the vast majority of these people, HIV infection was well controlled; 96% of people with HIV infection were taking ART, and 95% had HIV viral load less than 50 copies per milliliter (Table 2). Pre-exposure prophylaxis had been used in the month before presentation in 57% of people not known to have HIV infection.

clinical findings

Table 3. Table 3. Diagnosis and clinical characteristics of monkeypox in the case series. Figure 2. Figure 2. Lesions in people with confirmed human monkeypox virus infection.

Panel A shows the course of skin lesions in a person with monkeypox; images a1 and a2 show facial lesions, images b1 to b3 show a lesion on the penis, and images c1 and c2 show a lesion on the forehead. Polymerase chain reaction (PCR) status is indicated if available. IM denotes intramuscular and MSM men who have sex with men. Panel B shows oral and perioral lesions (image a, perioral umbilicated lesions; image b, perioral vesicular lesion on day 8, PCR positive; image c, left commissure ulcer on day 7, PCR positive; image d, tongue ulcer; image e, tongue lesion on day 5, positive PCR, and images f, g and h, pharyngeal lesions on days 0, 3 and 21, respectively, positive PCR on days 0 and 3 and negative on day 21). Panel C shows perianal, anal, and rectal lesions (image a, anal and perianal lesions on day 6, PCR positive; images b and c, rectal and anal lesions in a single person, PCR positive; image d, perianal ulcers, PCR positive) ; image e, anal lesions; image f, umbilicated perianal lesion on day 3, positive PCR; image g, umbilicated perianal lesions on day 3, positive PCR; and image h, perianal ulcer on day 2, PCR positive).

The features of monkeypox in this case series are summarized in Table 3. Skin lesions were seen in 95% of people (Figure 2). The most common anatomical sites were the anogenital area (73%); the trunk, arms or legs (55%); the face (25%); and palms and soles (10%). A wide spectrum of skin lesions were described (see clinical image web library), including macular, pustular, vesicular, and crusted lesions, and lesions in multiple phases were present simultaneously. Among those with skin lesions, 58% had lesions that were described as vesiculopustular. The number of injuries varied widely, with most people having fewer than 10 injuries. A total of 54 people had a single genital ulcer, highlighting the possibility of misdiagnosis as a different STI. Mucosal lesions were reported in 41% of people. Anorectal mucosal involvement was reported as a presenting symptom in 61 people; this involvement was associated with anorectal pain, proctitis, tenesmus, or diarrhea (or a combination of these symptoms). Oropharyngeal symptoms were reported as initial symptoms in 26 people; these symptoms included pharyngitis, odynophagia, epiglottitis, and oral or tonsillar lesions. In 3 people, conjunctival mucosal lesions were among the presenting symptoms. Common systemic features during the course of the disease included fever (in 62%), lethargy (41%), myalgia (31%), and headache (27%), symptoms that often preceded a generalized rash; lymphadenopathy was also common (56%).

The initial presenting feature and the sequence of subsequent cutaneous and systemic features (captured as free text) showed considerable variation. The most common presentation was an initial skin lesion(s), mainly in the anogenital area, the body (trunk or extremities), or the face (or a combination of these locations), with the number of lesions increasing over time and with or without features. systemic. (see the timeline series in the clinical imaging web library). Due to the observational nature of this case series, variability in time to presentation, and reliance on clinical records, a clear timeline of potential exposure and symptoms was only available for 30 individuals. Of these 30 people, 23 had a clearly defined exposure event, with a median time from exposure to symptom development of 7 days (range, 3 to 20). Prodrome injuries occurred in 17 of the 30 people; however, isolated anogenital or oral lesions were also observed (13 individuals). The median time from the onset of symptoms to the first positive PCR result was 5 days (range, 2 to 20), and the median time from the development of the first skin lesion to the development of additional skin lesions was 5 days (range, 2 to 20). 2 to 11) (see web library of clinical images). In people for whom follow-up PCR data were available, the last time a lesion remained positive was 21 days after symptom onset.

The clinical presentation was similar between people with HIV infection and those without HIV infection. The clinical characteristics of people with HIV infection are shown in Table 2. Concomitant STIs were reported in 109 of 377 people (29%) tested, with gonorrhea, chlamydia, and syphilis found in 8%, 5%, and 9%, respectively, of those tested .


The suspected means of transmission of monkeypox virus as reported by the physician was close sexual contact in 95% of people. Sexual transmission could not be confirmed. A sexual history was recorded in 406 of 528 people; among these 406 individuals, the median number of sexual partners in the previous 3 months was 5 partners, 147 (28%) reported traveling abroad in the month prior to diagnosis, and 103 (20%) had attended large gatherings ( >30 people), such as Pride events. Overall, 169 (32%) were known to have visited sex venues on the site in the past month, and 106 (20%) reported engaging in “chemsex” (meaning sex associated with drugs such as mephedrone and methamphetamine crystalline) in the same period.

A total of 70 people (13%) were admitted to a hospital. The most common reasons for admission were pain management (21 people), mainly due to severe anorectal pain, and treatment of soft tissue superinfection (18). Other reasons included severe pharyngitis limiting oral intake (5 people), treatment of eye injuries (2), acute kidney injury (2), myocarditis (2), and infection control purposes (13). There was no difference in the frequency of admission according to serological status. Three new cases of HIV infection were identified.

Two types of serious complications were reported: one case of epiglottitis and two cases of myocarditis. Epiglottitis occurred in a person with HIV infection who had a CD4 cell count of less than 200 cells per cubic millimeter; the person was treated with tecovirimat and fully recovered. Cases of myocarditis were self-limited (<7 days) and resolved without antiviral therapy. One occurred in a person with HIV infection who had a CD4 cell count of 780 cells per cubic millimeter, and one occurred in a person without HIV infection. No deaths were reported.

In total, 5% of the 528 people received specific treatment against monkeypox. Drugs given included intravenous or topical cidofovir (in 2% of people), tecovirimat (2%), and vaccinia immunoglobulin (<1%).


Table 4. Table 4. Characteristics of 32 people with monkeypox according to the presence or absence of viral DNA in seminal fluid in PCR.

The health setting at initial presentation reflected referral patterns and included sexual health or HIV clinics, emergency departments and dermatology clinics, and, less frequently, primary care. A positive PCR result was most often obtained from skin or anogenital lesions (97%); other sites were sampled less frequently. Reported percentages of positive PCR results were 26% for nasopharyngeal samples, 3% for urine samples, and 7% for blood samples. Semen was analyzed in 32 people from five clinical centers and was PCR positive in 29 people (4 of these cases were previously reported19) (Table 4).