Correction: An earlier version of this article incorrectly identified the countries in which the new mpox strain was recorded. The article has been updated.
The highly contagious and severe MPOX strain is spreading across the continent after causing a major outbreak in Central Africa.
A surge in cases in the Democratic Republic of Congo and 12 other African countries prompted the World Health Organization to declare a global health emergency for the second time in two years last week, a day after Swedish authorities announced their first confirmed cases of the MPOX virus in the country.
The new variant has not yet reached the United States, but that doesn’t mean U.S. health officials aren’t preparing for the eventuality.
Here’s what you need to know about MPOX and the latest craze.
What is mpox?
Mpox, formerly known as monkeypox, is part of the same family of viruses that cause smallpox. It is not related to chickenpox, according to the Centers for Disease Control and Prevention.
Discovered in 1958, the virus was originally named monkeypox because that’s the animal it was first found in, not because it originated in monkeys, but the disease has been renamed mpox in recent years to avoid the stigma associated with monkeys.
The disease is zoonotic, meaning it can be transmitted from animals to humans, but it can also be spread from person to person through physical contact, according to the CDC.
In fact, more cases of person-to-person transmission have been reported since 2016, according to Politico.
There are two types of mpox: lineage I and lineage II. Lineage I is prevalent in Central Africa and lineage II is prevalent in West Africa. A new variant of lineage I, Ib, appears to spread more easily.
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Is there an occurrence of MPOX?
The outbreak has worsened in Congo and neighboring countries since 2023.
According to the Africa Centers for Disease Control and Prevention, in 2024 alone, more than 17,000 people in Central and East Africa, mostly in Congo, have been infected with MPOX, with more than 500 deaths. So far this year, MPOX cases have been recorded in 13 African countries, including the Democratic Republic of Congo, Uganda, Rwanda, Burundi and the Central African Republic.
This is a significant increase from 14,957 cases in 2023 and 7,146 cases in 2022.
Last Thursday, it was revealed that a traveller from Sweden had returned from a trip to Africa carrying the disease, marking the first confirmed case outside of Africa.
The Africa CDC has reported 500 deaths and, fearing further spread, has issued its own emergency declaration while also calling for international medical assistance. According to the WHO, the alert is called a “Public Health Emergency of International Concern (PHEIC),” the highest level of alert under international health law.
According to the University of Minnesota’s Center for Infectious Disease Research and Policy, about 10 million doses of vaccine would be needed to combat epidemics in Africa.
The United States has announced it will donate 50,000 doses of its vaccine to Congo, but experts predict that stopping the virus will require millions more doses from Western countries, especially the U.S. To make this happen, vaccine manufacturers will need to significantly increase production.
Is mpox in the US?
Meanwhile, U.S. authorities are preparing for the new MPOX strain to eventually reach the United States.
But in a warning last week, the CDC said the risk of the virus spreading in the US is “very low” at this time.
CDC has also issued a health alert and travel notice regarding the more virulent MPOX strain in Congo and neighboring countries, encouraging health care providers and health agencies to monitor for symptoms and ask patients about recent travel to affected areas.
According to Reuters, the United States still reports a few cases each week caused by a less severe strain of the virus, but those cases are caused by a different strain of MPOX that emerged in 2022, clade II.
Mpox in a graphic presentation: what you need to know after WHO declares global emergency
What happened to mpox in 2022?
This new MPOX strain is slightly different from the strain that has been circulating in the United States since the global pandemic began in 2022.
Lineage II strains were largely contained to the African continent until spring 2022, when they suddenly emerged in Europe and then the United States. The first cases were confirmed in the United States in mid-May of that year, and the outbreak peaked with 638 cases reported by August 1.
Most of the spread was driven by infections in major cities such as New York, Los Angeles, and San Francisco during summer social events such as Pride Month. The state of emergency in the United States over the spread of the virus ended on January 31, 2023.
According to recent CDC data, since 2022, there have been clade II MPOX outbreaks in the United States, mostly among gay men but also among non-binary and transgender people. Overall, over 32,000 people in the United States have been infected and 58 have died from MPOX.
However, Mpox lineage I is not only more contagious but is also thought to be more severe, infecting tens of thousands of people, including children, sex workers and health care workers who lack proper protective equipment.
How does mpox spread?
According to the Centers for Disease Control and Prevention (CDC), Mpox is often spread through bodily fluids and physical contact.
The disease is usually transmitted to humans from rodents or primates through bites, aerosol transmission, or contact with infected body fluids. Person-to-person transmission usually occurs through respiratory secretions, infected skin lesions, or close contact with recently contaminated objects, according to the WHO.
What are the symptoms of MPOX?
Although the infection is usually mild, MPOX infections can last for two to four weeks and can be fatal if left untreated.
Most symptoms are flu-like and may include pus-filled skin lesions.
According to the CDC, within one to three days of infection, patients develop a rash on their face that spreads to other parts of the body, including the hands, feet, chest, face, mouth, and genitals. The rash starts out as pimples or blisters and can become very painful over time.
The fluid-filled lesions go through a series of stages before drying up and flaking off.
The incubation period (the time between infection and the appearance of symptoms) is usually 6-13 days but can be 5-21 days.
Other symptoms of mpox include:
Headache and fever, swollen lymph nodes, fatigue, body chills, back and body aches, a full body rash, blister-like lesions that start as small bumps
What is the treatment for mpox?
Vaccines are available and are recommended for people in high-risk populations.
The approved JYNNEOS vaccine provides protection against both lineage I and lineage II as a two-dose series given at least four weeks apart.
A recent CDC report said the vaccine is highly effective: Fewer than 1% of fully vaccinated people became infected, and those who did become infected had milder infections than those who were unvaccinated.
In the United States, more than 75% of the at-risk population has not completed the MPOX vaccination series, but many people who received the first dose of MPOX vaccine have not received the second dose, a CDC analysis found.
Contributing writer: Karen Weintraub, USA Today, Reuters
Eric Lagatta covers breaking and trending news for USA TODAY. He can be reached at elagatta@gannett.com.