- Previous outbreaks of monkeypox have been associated with a mild flu-like illness accompanied by a rash on the face, feet and hands
- In the current outbreak, painful anal, genital and throat lesions are commonly being reported
- Men who have sex with men who develop an unexpected rash or lesions should seek prompt medical attention
Background on monkeypox
Monkeypox is an illness caused by a germ called monkeypox virus. This virus is related to another virus that causes smallpox. Historically, even up to the first half of the 20th century, smallpox was a relatively common disease. However, a successful vaccination campaign led by the World Health Organization (WHO) resulted in the disappearance of smallpox, and by 1980 the WHO declared smallpox eradicated. As smallpox no longer was an issue, routine vaccination against this disease ceased. Some scientists think that as smallpox vaccination programs ended, immunity to the related virus that causes monkeypox decreased.
Monkeypox was first reported in children in parts of the Democratic Republic of the Congo in the 1970s and subsequently Nigeria. In these countries it became endemic because it can infect some animals (squirrels, mice, rats and monkeys) that live there. These infected animals act as a reservoir for the virus. When infected animals in these countries come into contact with people, they can spread the virus to them. Since the 1970s, the age at which monkeypox could occur gradually increased and eventually adults began to be affected.
In the past two decades, sporadic cases of monkeypox occurred in Europe and the U.S., but these were associated with people who had travelled to regions that had a history of monkeypox outbreaks. In such cases, there was limited spread from one person to another.
However, in May 2022, doctors in England and subsequently in Western Europe recognized the first cases of what would eventually be a large outbreak of monkeypox. Cases then quickly emerged in Canada, the U.S. and other countries. Unlike previous outbreaks, the people affected by the present outbreak are overwhelmingly gay, bisexual and other men who have sex with men (MSM). Reports from around the world suggest that the vast majority of people who are diagnosed with monkeypox in the current outbreak will recover after several weeks. Recent reports have also indicated that some affected people can experience severe and debilitating symptoms of monkeypox.
Severe symptoms of monkeypox in some people
Historically, prior outbreaks of monkeypox were usually associated with a relatively mild illness—usually general symptoms of a viral infection (fever, fatigue, muscle aches and pain, swollen lymph nodes) followed by a rash on the face, soles of the feet and palms of the hand. However, recent reports from high-income countries indicate that men with monkeypox can also experience ulcers in or on the genitals, around or in the anus and rectum, and in the throat. These ulcers can be extremely painful and, in some cases, require opioids to help manage the pain.
What’s more, the course of illness associated with monkeypox now seems different than in past reports from places where monkeypox has typically occurred. In the current outbreak, some people have developed oral or anal and genital ulcers before experiencing fever and other symptoms usually associated with viral infections (and monkeypox). In some cases, the lesions became infected with bacteria and required antibiotics in order to prevent serious complications.
Monkeypox is a new disease in Canada and other high-income countries. As a result, it is not well understood by doctors and scientists. Over time, as more cases are documented and studied, overall knowledge will increase. Research is underway and limited supplies of a vaccine (Imvamune) are available. This vaccine is being deployed by public health authorities to people at high risk of becoming infected with monkeypox virus. Contact your local public health authority to find out more about the availability and criteria for vaccination in your region.
For the latest information about monkeypox in Canada, including prevention, see this link.
Spread of monkeypox
In the current outbreak, monkeypox virus is spread mainly in the following ways in Canada and other high-income countries:
- from person to person
- through direct contact with contaminated objects
Person-to-person transmission
The Public Health Agency of Canada (PHAC) has made the following statement about person-to-person spread of the virus:
“Monkeypox virus can spread from person to person through contact with an infected person’s lesions or scabs that may be found on the skin or mucosal surfaces (such as eyes, mouth, throat, genitalia, anus, or rectum).”
PHAC states that “it may also be possible for it to spread through contact with an infected person’s body fluids such as blood, saliva and semen. This can occur in the following cases”:
- during sexual contact, including oral and non-penetrative contact
- when providing care
- when living in the same household
The U.S. Centers for Disease Control and Prevention (CDC) notes that additional contact that can spread monkeypox virus includes “hugging, massage and kissing” an infected person.
PHAC warns that “an infected pregnant person may also pass on the virus to their developing fetus through the placenta.”
Scientists do not yet know if an infected person without symptoms can spread the virus to others.
Contaminated objects
PHAC has stated that coming into contact with certain objects, such as those below, that were touched by a person with monkeypox virus could lead to infection:
- clothing
- bedding
- towels
PHAC also notes that monkeypox virus could spread if the following objects are shared with someone who has the illness:
- razors
- utensils
- needles
- sex toys
- toothbrushes
In addition, PHAC states that “the virus may spread through respiratory particles, such as from talking, breathing, coughing or sneezing, during close contact.” However, public health scientists are still collecting data on this mode of transmission.
The current outbreak
In a recent report, doctors in England noticed that in many cases where monkeypox was extensively investigated, affected men first developed lesions on the genitals/anus or inside the anus and throat. The doctors suspect that lesions first occurred in these tissues because they were likely the first point of contact with the virus. The population overwhelmingly affected has been MSM, most of whom reported recent sexual contact, according to the English doctors. All of this information suggests that in many cases among MSM monkeypox virus is spread during skin-to-skin contact that occurs during sex and/or due to exposure to infected body fluids.
MSM who develop unexpected rash, skin lesions (including on the genitals) or internal lesions (in the throat and anus) should immediately contact a doctor to be assessed.
Although in the current outbreak monkeypox is affecting mostly MSM, reports suggest that small numbers of women and children have also been infected. In some cases, this has occurred in households where a family member has monkeypox.
A study in England
A team of researchers at Guy and St. Thomas NHS Foundation Trust (a network of hospitals and community health centres in London, England) reviewed health information collected from 197 men who were ultimately diagnosed with monkeypox using PCR (polymerase chain reaction). In total, 196 were MSM, and their average age was 38 years (ranging between 21 and 67 years). Seventy of the men (36%) also had HIV. Although some of the men had serious symptoms and required hospitalization, none of them died.
Information from these cases was analysed by the research team after the men had initially been treated by doctors who suspected causes other than monkeypox. These cases occurred as the ongoing monkeypox outbreak was unfolding. Since monkeypox is largely a new disease in high-income countries, doctors were understandably initially confused about the cause of the illness their patients had.
As monkeypox is a new and poorly understood illness, it can be very scary for people who experience it, particularly if they have severe symptoms. However, it is important to bear in mind that the vast majority of people with monkeypox in the current outbreak will recover or have already done so. Furthermore, most people with monkeypox have not required hospitalization and can recover at home with medical advice.
Researchers in many countries are racing to report their findings about the emerging outbreak of monkeypox in the hope that the information can help improve the care of patients. As is typical of the initial months of any emerging outbreak, some details may not have been captured in reports. Over time, as data from thousands of cases of monkeypox in high-income countries are analysed, doctors and scientists will have a better idea of the range of symptoms and complications that can occur in people.
In this report, we focus on clusters of symptoms and issues noted by the English researchers to highlight differences with past outbreaks of monkeypox.
Rash and lesions
Historically, the rash associated with monkeypox first appeared as small flat red areas on the skin, usually affecting the face, hands and legs—rarely the anus and genitals. Subsequently, these areas would simultaneously become raised and a few days later they would form lesions. Eventually the lesions would become softer and ooze fluid. After this latter stage, they would harden and form scabs. Several days later the scabs would fall off, leaving a scar, and the person would be considered recovered from monkeypox.
The English researchers noted that in the present outbreak not all areas affected by rash would form lesions. Also, not all the lesions evolved at the same rate in affected patients.
Common locations of skin lesions in the English patients were as follows:
- genitals
- area around the anus and inside the anus
These ano-genital lesions occurred in 88% of patients.
Monkeypox skin lesions are usually itchy and can later become painful.
At the point that the men sought care, they all had symptoms of rash and lesions on or inside the anus or throat. On average, initially the men had five lesions.
Twenty-two men had just one lesion at the time they sought care. In 17 of these men, these solitary lesions were in the ano-genital region.
General symptoms
Many viral illnesses are initially associated with generalized or systemic symptoms as the immune system recognizes that it is under attack and mounts defensive measures. In the English study, 170 men reported a systemic illness with the following common symptoms:
- fever
- persistently swollen lymph nodes
- muscle soreness and pain
Historically, these generalized symptoms occurred before the appearance of monkeypox skin lesions. However, in the current outbreak, researchers found that nearly 40% of men first developed skin lesions/ulcers before they developed general symptoms of a viral infection. In 14% of men, the lesions were in the anus or throat prior to the occurrence of general symptoms.
Just one initial lesion
The researchers stated that 22 of the men initially developed one small lesion on their skin. For some men, this was the only lesion that they developed. However, in some other men, this single lesion could lead to complications, as outlined in the case below.
A 53-year-old man with HIV and a suppressed viral load sought care because of a small lesion on his right thigh. The lesion subsequently grew larger and caused swelling and redness in the surrounding tissue. His family doctor prescribed the antibiotic flucloxacillin, but the lesion kept growing and reached a size of 4x2 centimetres. Due to this increase in size, the man went to the hospital.
On examination, doctors found swollen lymph nodes in his groin. Ultrasound scans revealed extensive inflammation in his thigh and another lesion. He tested negative for common sexually transmitted infections (STIs). Doctors prescribed a combination of antibiotics—amoxicillin + clavulanic acid (sold as Augmentin or co-amoxiclav). Like all men in this report, he subsequently tested positive for monkeypox virus and eventually recovered. Doctors noted that his case puzzled them because he did not have known recent sexual contact or other exposure to the virus.
Lesions at different stages
Historically, monkeypox lesions appeared on a person’s skin at the same time and evolved at the same pace. However, the researchers found that more than 33% of patients had skin lesions “at different stages of evolution.” The following example underscores the complexity of the evolution of lesions in some people.
A 48-year-old man first developed a single lesion on his scrotum. Subsequently, additional lesions appeared on the base of his penis and on his foreskin. Three days after the first lesions appeared, additional lesions oozing fluid appeared on his arms, behind his knees, below one ear and on his face. The lesions on his genitals then developed into ulcers. He was treated with flucloxacillin. Five days after his first lesion appeared, he developed fever, muscle pain, back pain, headache and lack of energy.
Seventeen days after his first lesion appeared, the genital lesions had formed crusts, suggesting that they were healing, but new lesions on his hands appeared at that time. The lesions on his hands began oozing fluid.
On the 24th day after symptoms first appeared, lesions on his hands, legs and face had subsided and crusted. However, the genital lesions which had previously become crusted then became ulcerated. Doctors suspected that these new ulcers formed because of bacterial infection (with bacteria unrelated to STIs). This was confirmed with analysis of swabs taken from the lesions. He was treated with Augmentin and recovered.
Mouth and throat complications
A total of 27 men reported mouth and/or throat problems, including the following inside the throat:
- severe swelling
- blisters
- abscesses
The case that follows underscores complications that can arise from oral manifestations of monkeypox.
A 25-year-old man developed pain in the right side of his throat. Subsequently, he developed fever and swelling under his right jaw, together with pain and fatigue. The swelling worsened and he had difficulty swallowing and breathing. He was referred to a clinic specializing in ear, nose and throat issues. At that clinic, doctors noticed that he had one skin lesion on his arm. A swab of the lesion was positive for monkeypox and he was hospitalized. Subsequently, more lesions appeared on his body. Doctors tested the man for an extensive array of common viral infections, but all tests were negative.
An ulcer appeared on his throat and oozed yellow-green pus. Lymph nodes on the right side of his neck were swollen. A swab of the tonsils was positive for monkeypox. There were no anal or genital lesions.
The man was treated with two antibiotics, benzyl penicillin and metronidazole, to treat presumed bacterial complications. During his stay at the hospital, he gradually improved.
Lesions that merged
One 40-year-old man with HIV who had a suppressed viral load and more than 500 CD4+ cells sought medical help after lesions appeared at the base of his penis. He attributed the lesions to infected cuts during shaving.
He next developed further symptoms, such as:
- fever
- swollen lymph nodes in his neck
- headache
- lack of energy
- loss of appetite
Subsequently, lesions began to appear on other parts of his body (face, hands, torso, thighs and further along his penis). There was redness and swelling around the lesions. A doctor prescribed the antibiotic flucloxacillin.
Several days later his genital lesions formed scabs, suggesting that they were healing. However, the genital lesions then did something unexpected—they merged and formed large ulcers, exuding a yellow pus. He sought hospital care for severe pain, wound cleaning and treatment of his genital ulcers. Doctors suspected that his genital lesions had become infected with bacteria and analysis of swabs of the lesions confirmed this.
Swabs of his throat, anus and the opening of his penis tested negative for common STIs. He was given intravenous antibiotics (Augmentin), an antibiotic cream (Fucidin) and a skin wash (Octenisan). His lesions gradually resolved. He was given oral antibiotics upon leaving the hospital five days after being admitted.
HIV and monkeypox
In the English study, a total of 70 men (36%) with monkeypox also had HIV (in most cases HIV infection was a longstanding condition). Sixty-four of these men (91%) were taking HIV treatment (ART) and fifty-five of them (79%) had a suppressed viral load. The average CD4+ count of the men with HIV was 664 cells/mm3.
Other sexually transmitted infections
Among the men who were tested for STIs, commonly found infections were as follows:
- gonorrhoea
- chlamydia
- herpes
- syphilis
Altogether, researchers found that 31% of men in the study had an STI. This underscores the importance of screening men with a monkeypox diagnosis for STIs and offering treatment when necessary.
Hospitalization and monkeypox
A total of 25 men were hospitalized. In five cases, men were hospitalized because they were unable to isolate themselves at home.
The main clinical reasons for hospitalization were as follows:
- severe anal or rectal pain
- fluid buildup in the penis
Less common reasons for hospitalization included the following:
- abscess in the tonsils
- abscess in the groin or anal area
- eye care because of swelling and redness (monkeypox can cause eye complications including blindness)
- inability to urinate (this can happen due to severe swelling of the penis)
Rectal pain
The way that monkeypox evolved in the man detailed below underscores how some men in the current outbreak can have a different presentation of symptoms and complications than in previous outbreaks.
The man was 46 years old with HIV and a suppressed viral load. He had a CD4+ count of 1,200 cells/mm3.
His initial symptoms were:
- fever
- sore throat
- lack of energy
He then developed rectal pain. Doctors initially treated him for a suspected bacterial infection of the rectum and prescribed the antibiotic doxycycline. Subsequently, a rash spread over his arms and torso. One week after his initial symptoms appeared, he developed such severe rectal pain that he required hospitalization (and prescription pain relievers). Screening for common STIs yielded negative results. Due to persistent symptoms, including oral ulcers, he was given the antiviral drug tecovirimat (Tpoxx) at a dose of 600 mg twice daily for two consecutive weeks.
A magnetic resonance imaging (MRI) scan taken 12 days after the man first sought care revealed a damaged rectum and inflammation. Doctors suspected a bacterial infection of his rectum. To treat this infection and help prevent further complications, he was given intravenous antibiotics—ceftriaxone and metronidazole.
Although a biopsy was not done (due to severe pain), it is possible that the man first developed a rectal ulcer due to monkeypox virus and the ulcer then became infected with bacteria.
Fluid accumulation in the penis
A total of 31 men had fluid buildup in the tissues of their penis, causing parts of it to become swollen. This likely arose because of inflammation caused by monkeypox lesions in or on the penis. Although very painful, this swelling of parts of the penis did not cause destruction of the penile tissue, and urologists advised the use of cold compresses, massage and pain medicine (ibuprofen or morphine), along with anesthetic creams or gels as needed.
Control of pain and inflammation
Some patients with mild to moderate pain were given over-the-counter remedies— acetaminophen and ibuprofen. Other patients with more severe pain were given opioids. In some cases, doctors prescribed creams containing the anesthetic lidocaine that could be applied to painful parts of the skin. One man had such severe rectal pain that doctors gave him control over the frequency of his dosing of fentanyl. As opioids can cause constipation, some men also received laxatives.
Doctors also prescribed suppositories of emollients to help ease the passage of stools. In some cases, they also prescribed suppositories of the drug mesalamine, as it has anti-inflammatory effects. In other cases, they prescribed corticosteroids for the same reason.
Commenting on the use of medicines for pain and inflammation in men with monkeypox, the doctors stated that “to date, no adverse events associated with these treatments have been observed.”
On average, participants were hospitalized for eight days.
Bear in mind
The present report from England underscores the sometimes painful and complex course of illness associated with the current outbreak of monkeypox. Issues such as fluid buildup in the penis, anal lesions and severe rectal or throat pain were relatively common. Additionally, some men’s lesions became infected with bacteria and developed complications requiring antibiotics.
It is important to note that this report from patients seen at hospitals in England would have collected information from severely ill patients. This report is not representative of all people who become ill with monkeypox.
The researchers stated that there was no connection between the number of lesions a person had and the severity of their illness.
The researchers made the following statement: “The predilection of lesions to genital, perianal, and perioral or tonsillar areas, and the history of recent sexual contact in 96% of our cohort suggests lesions may initially form at the site of inoculation, followed by the development of systemic symptoms and subsequent dissemination of lesions.” This statement suggests that the tissues in the genitals, anus and mouth/throat were the point of first contact of monkeypox virus with the body. This observation by the researchers supports the sexual spread of the virus.
The researchers noted that “lesions appearing at different stages and timepoints could be a consequence of [people transferring monkeypox virus after touching a lesion to another point on their body].” This is understandable, as monkeypox lesions can be itchy. This underscores the need to keep lesions covered and for frequent handwashing by people with monkeypox so that they do not spread the virus around their body.
The researchers also found that some patients had widespread rash that did not ultimately transform into lesions.
Anecdotal reports suggest that in addition to pain some people with monkeypox can develop severe fatigue.
As more research is conducted into monkeypox, more information will become available on its symptoms and complications and how best to manage them. Research on the range of symptoms associated with monkeypox and the proportion of people who develop serious symptoms is particularly needed.
—Sean R. Hosein
Resources
Monkeypox: How it spreads, prevention and risks – Government of Canada
What you need to know about monkeypox in Montreal – Santé Montreal
Monkeypox – B.C. Centre for Disease Control (BCCDC)
Monkeypox – U.S. Centers for Disease Control and Prevention (CDC)
REFERENCES:
- Patel A, Bilinska J, Tam JCH, et al. Clinical features and novel presentations of human monkeypox in a central London centre during the 2022 outbreak: descriptive case series. BMJ. 2022 Jul 28;378:e072410.
- Sukhdeo SS, Aldhaheri K, Lam PW, et al. A case of human monkeypox in Canada. CMAJ. 2022 Aug 2;194(29):E1031-E1035.
- Thornhill JP, Barkati S, Walmsley S, et al. Monkeypox virus infection in humans across 16 countries – April-June 2022. New England Journal of Medicine. 2022; in press.