EXPPLAINER: What is monkeypox and where is it spreading?
European and US health authorities have identified a number of cases of smallpox in recent days, mostly in young men. It is a surprising outbreak of a disease that is rarely seen outside Africa.
Health officials around the world are keeping an eye out for more cases because, for the first time, the disease appears to be spreading among people who have not traveled to Africa. They emphasize, however, that the risk to the general population is low.
WHAT IS MONKEYPOX?
Monkeypox is a virus that originates in wildlife such as rodents and primates, and sometimes exceeds humans. Most human cases have been 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 “smallpox-like” disease in research monkeys – hence the name monkeypox. The first known human infection was in 1970, in a 9-year-old boy in a remote part of the Congo.
WHAT ARE THE SYMPTOMS AND HOW IS IT TREATED?
Monkeypox belongs to the same family as the smallpox virus but causes mild symptoms.
Most patients experience only fever, body aches, chills and fatigue. People with more serious illnesses can develop rashes and sores on the face and hands that can spread to other parts of the body.
The incubation period is from about five days to three weeks. Most people recover within two to four weeks without having to be hospitalized.
Smallpox can be fatal in up to 10 people and is thought to be more severe in children.
People exposed to the virus are often given one of several smallpox vaccines, which 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 for the smallpox vaccine.
HOW MANY CASES OF MONKEYPOX TYPICALLY?
The World Health Organization estimates that there are thousands of monkeypox infections in about a dozen African countries each year. Most are in the Congo, which reports about 6,000 cases a year, and Nigeria, with about 3,000 cases a year.
Irregular health monitoring systems mean that many infected people are likely to be lost, experts say.
Isolated cases of monkeypox are sometimes spotted outside Africa, including in the United States and Britain. The cases are typically associated with travel to Africa or contact with animals from areas where the disease is more common.
In 2003, 47 people in six U.S. states had confirmed or probable cases. They caught the virus from prairie domestic dogs that were kept near small mammals imported from Ghana.
WHAT IS DIFFERENT ABOUT THESE CASES?
It is the first time that monkeypox seems to be spreading among people who have not traveled to Africa. Most cases involve men who have had sex with men.
In Europe, infections have been reported in Britain, Italy, Portugal, Spain and Sweden.
The UK Health Security Agency has said not all of its cases are connected, suggesting several chains of transmission are taking place. Infections in Portugal were detected at a sexual health clinic, where men sought help for wounds on their genitals.
On Wednesday, U.S. officials reported a case of smallpox in a man who had recently traveled to Canada. The Public Health Agency of Canada also confirmed two cases related to that positive test. Health officials in Quebec earlier said they had suspected 17 cases in the Montreal area.
IS MONKEYPOX MISSED BY SEX?
It is possible, but not clear at the moment.
Smallpox has not been documented before it was spread through sex, but can be transmitted through close contact with infected people, their body fluids and their clothing or bedding. .
Michael Skinner, a virologist at Imperial College London, said it was too early to determine how men in the UK were infected.
“By nature, sexual activity involves intimate contact, which is expected 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 the smallpox of monkeys said that sex qualifies as the kind of close contact needed to transmit the disease.
The UK cases “do not necessarily imply any recent change in the route of virus transmission,” Balloux said.