This article by Michael Head, University of Southampton originally appeared in The Conversation and is posted here with permission.
Four new cases of monkeypox were reported in the UK, bringing the total number of confirmed cases to seven. The UK Health Security Agency (UKHSA) is urgently searching for the source of the outbreak.
The first case in the current outbreak was confirmed on 6 May. But this is not the first time that monkeypox has been reported in the UK. Three cases were also reported in 2021 and one in 2018. However, these infections are rarely seen in the UK and are largely associated with international travel from endemic areas, including parts of West and Central Africa.
On May 18, five cases of monkeypox were reported in Portugal, with investigations underway into another 20 suspected cases. On the same day, Spanish health authorities reported eight suspected cases of men who had sex with men.
This is the largest outbreak of monkeypox ever in Europe. It is not known if the cases are related.
Monkeypox, as the name implies, was first found in laboratory monkeys in the late 1950s. However, scientists are not sure if monkeys are the main animal reservoir (carriers of the virus), so the name may be somewhat of a misnomer. The last thought is that the main tank is probably smaller animals, such as rodents.
Unlike COVID, monkeypox is not easily transmitted from human to human. It usually requires interaction with animals that carry the virus, close contact with infected people, or contact with “tolerants” (such as contaminated clothing, towels, or furniture). Also unlike COVID, monkeypox is not known to spread asymptomatically. However, the evidence for monkeypox is weak, and the current outbreak will provide new knowledge about its impact and transmission.
Monkeypox belongs to the same family of viruses as smallpox, but is less transmissible. People who get it usually develop a fever, a characteristic rash, and blisters. The disease is usually self-recovering, with symptoms disappearing after a few weeks. However, monkeypox can cause severe disease, with outbreaks typically showing a case fatality rate (the proportion of people with the disease who die from it) between 1% and 15%, with the potential for severe illness and death in children.
The UK Health and Human Services Authority (UKHSA) says some cases in the May 2022 outbreak cannot be explained by recent international travel, suggesting there may have been some “community transmission”. Four of the seven cases involved gay, bisexual, or other men who have sex with men. The UKHSA epidemiologist tweeted that this was “strongly suggestive of spread in sexual networks”. Cases in Spain may also be the subject of a similar study.
So the transmission here may be somewhat unusual compared to previous outbreaks. While there is much we don’t know about monkeypox, we do know that the virus can be transmitted through close contact, for example, including prolonged skin-to-skin contact.
There is no evidence that it is a sexually transmitted infection such as HIV or chlamydia. What’s more, in the UK outbreak, close contact during sexual or intimate activity may be a major factor during transmission.
This may be the first time that monkeypox transmission through sexual contact or intimate activity has been documented. But the implications are not so great that we know that close contact is required for transmission. The social dynamics around infectious disease transmission mean that this finding could be very useful for public health teams involved in “contact tracing” – to find other people who may have been exposed to the virus.
Extremely low risk for the general public
The risk of monkeypox to the general public in the UK is very low, and the NHS has specialist units focused on treating these types of tropical infections. Fortunately, there are ways to beat the virus.
The U.S. Centers for Disease Control and Prevention highlights how the smallpox vaccine, cidofovir (an antiviral drug), and Cassia immune globulin are used to control an outbreak of monkeypox.
However, unlike the smallpox vaccine, there is no specific vaccine to protect against monkeypox. Some experts have suggested that stopping widespread smallpox vaccination may reduce a population’s immunity to monkeypox, making cases and outbreaks more likely.
A 2019 meeting at Chatham House in London suggested that the unintended consequence of smallpox eradication could be “emerging or re-emerging human monkeypox that may fill the epidemiological niche vacated by smallpox”.
However, cases of imported monkeypox and other tropical infections (such as Ebola, malaria, and Lassa fever) indicate a broader burden of disease elsewhere in the world, usually in low-income countries with limited access to health care. It may be that in a post-pandemic environment, we should pay more attention to understanding the local and global impacts of Lhasa, monkeypox, Ebola and other rare and dangerous pathogens.
Michael Head, Senior Research Fellow in Global Health, University of Southampton
This article has been republished from The Conversation under a Creative Commons license. Read the original article.