Almost all cases in this outbreak were among gay, bisexual and other men who have sex with men, and most transmission has been associated with sexual activity. However, experts fear that if it is not managed promptly through testing, vaccination and treatment, the virus could spread beyond this group and could become endemic in more countries.
“We have shown that current international case definitions need to be expanded to add symptoms that are not currently included, such as ulcers in the mouth, anal mucosa and single ulcers,” said study lead author Professor Chloe Orkin from Queen Mary University. from London. “Expanding the definition of the condition will help clinicians identify the infection more easily and thus prevent people from transmitting it.”
As previously reported by aidsmap, the UK Health Security Agency (UKHSA) reported the first case of monkeypox in the current outbreak on May 7. As of 18 July, the UKHSA had identified 2,137 confirmed cases in the UK. The European Center for Disease Prevention and Control reported 10,604 cases across the European region as of July 19, while the US Centers for Disease Control and Prevention collected a total of 15,848 cases worldwide, including 15,605 in countries that historically did not report a disease. Monkey pox.
Orkin and a long list of colleagues formed an international collaborative group of clinicians (the SHARE-net Clinical Group) who contributed data on monkeypox cases in 10 European countries, the United States, Canada, Mexico, Australia, Argentina, and Israel.
Together, they collected information on 528 cases diagnosed with a positive test for monkeypox virus by PCR between April 27 and June 24. Most were diagnosed in HIV clinics, sexual health clinics, or emergency departments.
All but one of the subjects with monkeypox were men, and the remaining person was identified as transgender or non-binary. There were no women in this case series, although dozens of women with monkeypox were reported by individual countries. Almost all of them said they were gay (96%), 2% were bisexual and 2% were heterosexual.
The median age was 39 years. Fifty-six subjects were over 50 years of age, and 9% had previously received the smallpox vaccine, which indicates that the previous vaccination is not completely protective. The authors did not say if any of them were under 18, but countries have reported a small number of cases among children. Three-quarters of them were white, 12% Hispanic, 5% black and 4% of mixed race.
Given their HIV status, 41% were HIV positive. Of these, most (96%) were on antiretroviral therapy, and the majority (61%) were taking reductase inhibitors. Most had well-controlled HIV, with 95% having an undetectable viral load (<50); The average CD4 cell count was high, 680. Of the 59% of people who had HIV or had an unknown condition, more than half were receiving pre-exposure prophylaxis (PrEP). Hepatitis B (1%) and hepatitis C (2%) were uncommon. "While people with HIV account for more than 40% of cases to date, it is reassuring that HIV status has not been associated with monkeypox severity," said Laura Waters, president of the British HIV Association.
According to the study authors, “transmission through sexual activity is suspected” in 95% of people with monkeypox in this case series.
The monkeypox virus is transmitted through close physical contact, which can include skin-to-skin contact, exchange of body fluids, and transmission through respiratory droplets at close range, although it does not spread through the air for longer distances. The virus can also be spread through clothing, bed linen, or surfaces that have come into contact with liquids from pests, although this appears to be less common. It is not yet known whether the virus is transmitted through semen or vaginal fluid. Prior to the current outbreak, monkeypox was not thought to be easily transmitted from person to person, but MSM sexual networks provided a favorable environment for rapid transmission.
In fact, this group had several sexual risk factors. Among those screened for sexually transmitted infections (STI), 29% had positive test results, with syphilis (9%), gonorrhea (8%) and chlamydia (5%) being the most common. Among those with a known sexual history, the average number of sexual partners was five in the previous three months. One in five reported “chemsex” (the use of recreational drugs during sex) and 32% reported having attended sex venues during the previous months. Just over a quarter reported traveling abroad in the month before diagnosis, mostly to European countries.
‘Close sexual contact’ was by far the most common suspected mode of transmission (95%). About a quarter (26%) had contact with someone known to have monkeypox. Close non-sexual contact and domestic contact were suspected in 1% of cases, while 3% had an unknown transmission route.
“It is important to stress that monkeypox is not a sexually transmitted infection in the traditional sense; it can be acquired through any type of close physical contact,” said Dr John Thornhill, lead study author from Barts NHS Health Trust and Queen Mary University of London. “However, our work indicates that most transmissions to date have been related to sexual activity—primarily, but not exclusively, among men who have sex with men. This research study increases our understanding of the ways it spreads and the groups in which it spreads, which will aid in the rapid identification of new cases and allow us to offer preventive strategies, such as vaccinations, to individuals at greater risk. ”
Symptoms and treatment
Only 23 people diagnosed with monkeypox had an exposure history clear enough to determine the incubation time, which ranges from three to 20 days. Most (97%) had positive anogenital skin or lesions smears and 26% had positive nasal or throat swabs. In addition, some had positive PCR tests for blood (7%), urine (3%) and semen samples (5%).
However, “This may be accidental because we don’t know it [the virus] It is present at high enough levels to facilitate sexual transmission,” Thornhill said. “More work is needed to better understand this.”
Almost everyone with monkeypox (95%) had a rash or lesions, including 73% with lesions of the anus or genitals, 55% with lesions on the trunk or extremities, 41% with lesions of the mucosa (mostly anal, throat, or both ), 25% with lesions on the face and 10% with lesions on the palms or soles of the feet. However, 28 subjects (5%) did not develop lesions. Seventy-five subjects (14%) reported proctitis or proctitis. Other common symptoms are fever (62%), swollen lymph nodes (56%), fatigue (41%), muscle aches (31%), headache (27%), and sore throat (21%).
Some of the people included in the case series presented with symptoms not recognized in current medical definitions of monkeypox, including single genital lesions and sores on or inside the mouth or anus. In some cases, these symptoms are similar to those of common STDs, which can lead to misdiagnosis, and some people have contracted monkeypox and STDs. The study authors stressed the importance of educating healthcare providers on how to identify and manage these new clinical symptoms.
Seventy subjects (13%) were hospitalized, mostly for treatment of severe rectal pain (21 subjects), soft tissue infection (18 subjects) or sore throat that resulted in difficulty swallowing (5 subjects); 13 of them were in hospital for quarantine. Two people each had eye lesions, acute kidney injury, and myocarditis (inflammation of the heart muscle). Many men who shared their stories in the press or On social media She described severe pain in the anus or throat.
A small number of subjects (5%) were given antiviral treatment, which was in short supply and difficult to obtain. two each received tekovirimat (Tpoxxcidofovir (Vested) and one received xenia immunoglobulin (antibody therapy).
No deaths were reported in this case series. So far, there have been five deaths from monkeypox this year, all in African countries.
According to a press release about the report, “The results of this study, including identification of those most at risk of infection, will aid in the global response to the virus.” Public health interventions targeting this high-risk group can help detect the virus and slow its spread. Identification of the disease, tracing of contacts and advising people to isolate will be key components of the public health response.”
The study authors stressed that public health measures should be developed and implemented in collaboration with at-risk groups to ensure they are appropriate and harmless and to avoid messages that could lead to underground outbreaks.
“This international case series contributes to growing evidence about how monkeypox is transmitted, and in what populations,” said Dr. Will Nutland, co-founder of PrEPster. “The research should serve as another call to appropriately resource our responses to monkeypox, including scaling up testing, treatment, and vaccination programmes, to the key populations most affected by the virus.”