Fresh Mpox Warning Issued Ahead of Summer

Cases of mpox, previously known as monkeypox, may be increasing in the U.S. despite the availability of vaccinations against the disease.

The number of people with the virus is rising again, with 12 confirmed and one probable case of mpox being recorded by the Chicago Department of Public Health between April 17 and May 5, 2023, according to a report from the CDC. None of the patients had to go to the hospital, and nine of the 13 had received two JYNNEOS vaccine doses.

Mpox can lead to a skin rash, usually located on the hands, feet, chest, face, or mouth or near the genitals. It's spread by skin-to-skin contact, including sexual interaction, but also by hugging, kissing and any face-to-face contact, the CDC said.

Some 30,395 cases had been reported in the U.S. as of May 10, the majority of which arose during the initial breakout of the virus in the summer of 2022. Many of the affected people were men who have sex with men (MSM) and transgender people, and these communities are still considered most at risk, although anyone can catch the disease through non-sexual contact. In total, 42 people were recorded to have died from the infection in the U.S. since the outbreak began.

"About 94 percent of the cases occurred among men who reported sexual contact with other men. Almost all of the 42 people who died from mpox complications had unmanaged HIV infections," Kathryn H. Jacobsen, a professor of health studies and epidemiology at the University of Richmond, told Newsweek.

"The CDC is predicting that several cities in the United States will experience mpox outbreaks this summer," she said. "The total number of mpox cases this year is likely to be smaller than the number diagnosed last year because many of the individuals with the highest risk of encountering the virus through sexual contact have already received two doses of the JYNNEOS vaccine."

The symptoms of mpox are similar, but less clinically severe, to those of smallpox, and include skin lesions.

"Mpox infection is usually mild with a full recovery in a few weeks," Angela Brown, a midwife and clinical nurse at the University of South Australia, told Newsweek. "Mortality is likely higher in vulnerable groups such as in immunocompromised groups, newborn babies and pregnant or breastfeeding women. Symptoms include fever, headache, lymph node swelling, muscle aches, weakness and mucous membranes lesions/rash.

"In more severe cases the lesions can be more significant and can lead to secondary infections (skin, lung or blood). Those who have severe forms of the disease will often need hospital care with appropriate pain relief and antiviral medications and management of symptoms."

Despite the vaccine being available, and a large number of people taking it, it doesn't completely remove any risk of being infected.

"Two doses of the vaccine are only estimated to reduce the risk of infection by about 69 percent and a single dose is estimated to reduce the risk by only about 37 percent," Jacobsen said. "That means that even fully vaccinated individuals may remain at risk of contracting mpox if they have skin-to-skin contact with infected people. Several of the people diagnosed with mpox in the past month received two doses of JYNNEOS last year. Those cases highlight the need for behavioral prevention strategies, especially among men who have sex with men."

Only 23 percent of the at-risk population has taken the vaccine, however.

Medical professionals hope that the public attention the virus got last year, as well as the availability of the vaccine, may help to keep numbers down this summer.

"With public vigilance and awareness it is likely that this will remain manageable," Brown said. "There is a vaccine available to people who have been in contact with someone with mpox and this is also available to people from certain risk groups where transmission has been higher. The vaccine is also available to people who have participated in certain activities that may increase their risk.

"Those who are immune suppressed such as those with HIV are also at higher risk of more serious consequences including death," she said. "Additionally open conversations with health care providers around risk factors and ways to minimize transmission is critical."

Additionally, more public knowledge about the virus can help people identify symptoms in themselves and others.

"Now that people know more about what to look for, they can be more careful about avoiding contact with people who have lesions," Amy L. MacNeill, a poxvirus expert and associate professor of microbiology, immunology, and pathology at Colorado State University, told Newsweek. "Also, they can ask to be vaccinated to reduce the risk of serious disease if they do come in contact with the virus. One of the problems with the last outbreak is that some lesions were not easily seen (e.g. rectal lesions, oral lesions). If people are careful and take precautions, the resurgence should not be as bad as the last outbreak."

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