What is monkeypox and where does it spread?

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What is monkeypox and where does it spread?

Monkeypox virus illustration

An illustration of a smallpox virus. These viruses, which include chickenpox, monkeypox, and smallpox, are oval-shaped and have double-stranded DNA.
illustration: SCIENTIFIC PHOTO LIBRARY (AP)

New outbreaks of a rare disease called monkeypox have health experts on edge. Several countries including the US have recently reported cases of the virus infection. No deaths have been reported so far and the risk to the general public appears to be low for now. But it’s possible that something has changed about the virus or its relationship with humans, making it more transmissible.

Countries with reported cases of monkeypox

The first US case involved a Massachusetts resident who had recently traveled from Canada, where there were 13 suspected cases. Late Thursday afternoon, New York City Health Authorities reported a suspected monkeypox case currently being treated at Bellevue Hospital.

At least 11 countries including UK, Canada, Spain, Portugal, Italy, Sweden, and the US have documented cases of monkeypox. In the UK is the first reported case believed having contracted it in Nigeria. Australia reported his first case on Thursday in someone who had recently arrived from the UK. Germany, France and Belgium reported their first cases on Friday morning, and there are believed to be around 100 reported cases worldwide.

Also this morning the World Health Organization announced It will hold an emergency meeting on monkeypox where experts will advise on whether to declare the outbreaks a Public Health Emergency of International Concern (PHEIC). The last major and sustained outbreak of this type to receive PHEIC status is the Covid-19 pandemic.

monkey pox was first documented in Africa in the 1970s and has been occasionally sighted on the continent since. But it’s a zoonotic disease, meaning infections are usually transmitted from animals to humans (rodents are considered the primary vector, despite the name), rather than between humans. According to Andrew Pavia, an infectious disease physician at the University of Utah, these multiple outbreaks in several countries, with evidence of local transmission in some, are very different from what we’ve seen before. But there’s still no clear answer as to why this is happening, he adds.

“Historically there has been human-to-human spread, but it has been quite limited. We don’t know yet that it spreads more easily from person to person. That’s a possible explanation, but I’m not yet aware of any evidence to support this idea,” Pavia Gizmodo said in an email.

What is the monkeypox virus?

Monkeypox is caused by the eponymous virus, a member of the smallpox family. It is a close relative of the smallpox virus, the only human germ that has been completely eradicated. Like smallpox, monkeypox infection causes distinct, bumpy skin rashes that usually start on the face and spread throughout the body, along with flu-like symptoms.

It takes one to three weeks after exposure for symptoms to start, and people are usually sick for about two weeks. Up to 10% of victims can die from it, although the cases documented in the UK appear to be caused by a lineage of the virus known to be less virulent, with a mortality rate of almost 1%.

There are monkeypox remedies available that we could use if these outbreaks become more of a threat. Smallpox vaccines should continue to protect against monkeypox and can be given post-contact to prevent disease, so they can be used as part of a “ring vaccination” strategy against short-circuit outbreaks. There are approved antivirals that are also effective against smallpox virus infections.

Why is monkeypox spreading now?

It is plausible that the virus evolved in some way to make it inherently more contagious between humans. However, some scientists like Jo Walker, an epidemiologist and infectious disease modeler at the Yale School of Public Health, have done so speculated that this seemingly increased spread may actually be related to our victory over smallpox decades ago.

Smallpox was declared eradicated in 1980 through the efforts of a global mass immunization program that created a wide web of popular immunity. Smallpox viruses are known to cause cross-immunity with other related viruses (in fact, the weakened virus in the classic smallpox vaccine isn’t even smallpox). And this buffer of smallpox immunity may also have impeded the spread of monkeypox to humans. However, over time our collective protections have weakened for various reasons, which may have allowed monkeypox to finally spread further without having to change in any significant way.

A patient with monkeypox lesions.

A patient with monkeypox lesions.
picture: CDC (Getty Images)

“This ‘decreasing immunity’ is less due to waning immunity at the individual level and more to do with people dying with immunity and people being born without immunity and then not remaining immune,” Walker Gizmodo said in a Twitter message.

Walker notes that some researchers have done so long warned about monkeypox or similar viruses that will one day fill the niche left by smallpox, and some have argued that this is a major factor in why the germ made a reemergence in Nigeria as of 2017, after four decades with no reported cases.

Another possibility Pavia addresses is that a mysterious animal played an outsized role in seeding these outbreaks. In 2003, he points out, the largest known but still small outbreak of monkeypox was in the United States (47 total cases). traced back only to be brought into contact with infected prairie dogs – an unknown vector at the time.

At the same time, there is evidence of human-to-human transmission in at least some of these cases. In the UK and Spain, most cases have been found in young gay and bisexual men, raising the possibility that these infections were sexually transmitted. Other research has shown that monkeypox can theoretically survive in the environment in aerosol particles intact enough to be considered airborne.

Getting to the bottom of this monkeypox mystery requires classic medical detective work, Pavia said. Epidemiological investigations will attempt to identify the type of contact that led to people’s infections and the number of infections that appear to emerge from each index case. In the laboratory, the scientists will look for potentially relevant genetic changes in virus samples from patients or test whether these infections behave differently in model animals.

“Based on what we know today, there’s no reason to panic or for most people to worry, but it’s early days so that may change,” Pavia said.

This article was updated on May 20 with the latest case numbers.

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What is monkeypox and where does it spread?

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What is monkeypox and where does it spread?

AP – European and American health officials have identified a number of cases of monkeypox in recent days, mostly in young men. It’s a surprise outbreak of a disease rare outside of Africa.

Health officials around the world are on the lookout for more cases as the disease appears to be spreading for the first time among people who have not traveled to Africa. However, they emphasize that the risk to the general population is low.

What is monkeypox?

Monkeypox is a virus that originates from wild animals such as rodents and primates and occasionally spreads to humans. Most human cases have occurred in central and western Africa, where the disease is endemic.

The disease was first identified by scientists in 1958 when there were two outbreaks of a “smallpox-like” disease in research monkeys – hence the name monkeypox. The first known human infection occurred in 1970 in a 9-year-old boy in a remote part of Congo.

What are the symptoms and how is it treated?

Monkeypox belongs to the same virus family as smallpox but causes milder symptoms.

Most patients suffer only from fever, body aches, chills and fatigue. People with more severe illnesses can develop a rash and lesions on the face and hands, which can spread to other parts of the body.

The incubation period is about five days to three weeks. Most people recover in about two to four weeks without requiring hospitalization.

Monkeypox can kill up to 1 in 10 people and is thought to be more serious in children.

Individuals exposed to the virus are often given one of several smallpox vaccines that have been shown to be effective against monkeypox. Antiviral drugs are also being developed.

On Thursday, the European Center for Disease Prevention and Control recommended that all suspected cases be isolated and that high-risk contacts be offered the smallpox vaccine.

This 2003 electron micrograph, provided by the Centers for Disease Control and Prevention, shows mature, oval-shaped monkeypox virions (left) and spherical immature virions (right) obtained from a human skin sample. (Cynthia S. Goldsmith, Russell Regner/CDC via AP)

How many cases of monkeypox are there usually?

The World Health Organization estimates that there are thousands of monkeypox infections in about a dozen African countries each year. Most are in Congo, which reports about 6,000 cases annually, and Nigeria, with about 3,000 cases annually.

Incomplete health surveillance systems mean many infected people are likely to be missed, experts say.

Isolated cases of monkeypox are seen outside of Africa, including in the US and UK. Cases are typically related to travel to Africa or contact with animals from areas where the disease is more prevalent.

In 2003, 47 people in six US states had confirmed or probable cases. They caught the virus from prairie dogs kept near small mammals imported from Ghana.

What is different about these cases?

It’s the first time monkeypox seems to be spreading among people who haven’t traveled to Africa. In most cases, these are men who have had sex with men.

In Europe, infections have been reported in the UK, Italy, Portugal, Spain and Sweden.

Britain’s Health Security Agency said its cases were not all linked, suggesting multiple chains of transmission are taking place. The infections in Portugal were discovered at a sexual health clinic where the men were seeking help for lesions on their genitals.

On Wednesday, US officials reported a case of monkeypox in a man who recently traveled to Canada, where authorities are investigating suspected infections in the Montreal area.

Is monkeypox transmitted through sex?

It’s possible, but it’s unclear at the moment.

Monkeypox has not been documented as being spread through sex, but it can be spread through close contact with infected people, their bodily fluids, and their clothing or bedding.

Michael Skinner, a virologist at Imperial College London, said it was too early to determine how the UK’s men became infected.

“Sexual activity inherently involves intimate contact, which one would expect to increase the likelihood of transmission, regardless of a person’s sexual orientation and regardless of the mode of transmission,” Skinner said.

Francois Balloux, of University College London, said monkeypox qualifies sex as the type of close contact needed to transmit the disease.

The UK cases “do not necessarily imply a recent change in the transmission route of the virus,” Balloux said.

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