Like its close relative the smallpox virus, mpox (formerly known as monkeypox) is a pathogen in the Orthopoxvirus family.
It is transmitted through contaminated body fluids or close contact with infected humans and other animals, and can cause mild to severe illness – and in some cases, death.
What are the symptoms of mpox?
Approximately a week or two following infection, the virus gives rise to a fever, headaches, muscle aches, swollen lymph nodes, and exhaustion. Several days later a rash might appear, usually on or around the face, which can progress into blistery pustules that scab before healing in the following weeks.
Although in many ways similar in presentation to smallpox, mpox is fortunately regarded as self-limiting, making it far less severe.
Nonetheless, mpox is still seen as a serious illness that carries a risk of ongoing complications, from the effects of sepsis and encephalitis to blindness from eye infections. Without medical treatment or vaccination, nearly one in ten people infected are at risk of fatal complications, especially among young children.
Compared with the horrors of smallpox, which at its peak claimed nearly one out of every three infected, mpox might not seem that bad. But if we've learned anything from the COVID-19 pandemic, it's better to be safe than sorry when it comes to potentially deadly viruses.
How does mpox spread?
Mpox is spread between humans through close contact with someone who has the mpox rash. This could be face-to-face, skin-to-skin, mouth-to-mouth, or mouth-to-skin contact. The virus can be spread through droplets or short-range aerosols if someone has ulcers or sores in their mouth, according to the World Health Organization (WHO).
People are considered infectious until all of their lesions have crusted over, although scientists still have a lot to learn about the latest outbreaks.
Can you catch mpox from a surface?
An infectious person can transfer the mpox virus to a surface, such as clothing, mobile phones, toilet seats, and bedding. Someone else who handles these objects could then become infected.
According to the WHO, the virus can also spread to the fetus during gestation.
It's not clear as yet whether the virus can be spread between people by asymptomatic carriers.
Should we be worried about a mpox pandemic?
On 23 July, 2022, the WHO made an official announcement declaring the outbreak of mpox to be a global health emergency of international concern. At the time of the announcement more than 16,000 cases across 74 countries had been reported.
With the organization's experts unable to come to a consensus on whether this highest level of caution was warranted, it fell to the WHO chief Tedros Adhanom to make the final decision.
In the past, outbreaks have been limited to a handful of infected people, with little to no human-to-human transmission. Spread has therefore previously been restricted. What's more, unlike SARS-CoV-2, mpox can't spread through the air. With the smallpox vaccine effective against the virus, authorities are already well armed should concerns continue to escalate.
What the virus's apparent spread does represent is the ease with which viruses move with increased travel and relaxed hygiene. As seen with the AIDS epidemic in the 1980s, strong association with risk-taking behaviors and minority demographics can promote stigma that makes communication on the infections more challenging.
As well-positioned as we are as a society to prevent the spread of viruses, COVID-19 has shown how quickly populations can become complacent, mistrustful, and fatigued over communal and even personal healthcare.
Why was it called monkeypox?
The former name of monkeypox dates back to 1958, following an outbreak of the virus among laboratory test monkeys at a Copenhagen research facility. Don't let the name fool you though – while monkeys can catch and transmit the virus, it's more often caught through popular sources of so-called bushmeat like dormice and African squirrels.
It wouldn't be until 1970 that the first human case would be identified, as the WHO focused their efforts on eradicating smallpox in the Democratic Republic of the Congo. Today, the majority of infections are still found in this central African nation, though outbreaks have been reported in a number of neighboring countries.
Why is mpox spreading around the world now?
While the 2022 mpox outbreaks made headlines, it's not the first time the virus was found outside of African populations.
In mid-2003, 71 cases of the illness were reported to the CDC across six US states, with 35 confirmed through laboratory tests to be caused by the mpox virus. All of these confirmed cases were traced back to infected prairie dogs purchased from an animal distributor in Illinois, which in turn had been infected by Gambian giant rats and dormice imported from Ghana.
Three cases were also reported in the UK in 2018. Surprisingly, one of the cases was not directly related to the other two. All had recently been in Nigeria, where mpox is known to circulate.
On the face of it, the numerous concurrent outbreaks occurring mid-2022 might have the appearance of a potential pandemic, especially with the recent emergence of the devastating SARS-CoV-2. Numerous suspected and confirmed cases around the globe, including the US, UK, Spain, Portugal, Italy, and Australia, hint at unseen, widespread transmission.
Most of those infected appear to be the result of close intimate contact (primarily between men), who have been diagnosed following reporting to health clinics. There have been no reported deaths at the time of writing this article.
With no indication of a mutation that could be responsible for increasing the microbe's virulence, it's likely a sudden surge in travel with an easing of COVID restrictions could be contributing to the outbreaks.
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