The monkeypox virus has spread to 20 U.S. states and the nation’s capital.
Thus far, 113 infections have been reported, with the majority in California, New York, Illinois and Florida.
New Jersey’s Department of Health announced its first probable case on Monday and Missouri officials identified a potential case in a Kansas City resident over the weekend.
Other locations are reporting monkeypox and orthopoxvirus cases in the single digits, according to the Centers for Disease Control and Prevention (CDC).
The World Health Organization (WHO) is convening an emergency meeting this week to determine whether the outbreak should be considered a global health emergency.
The United Nations (UN) health agency said people with monkeypox could be infectious for up to four weeks and has advised those infected to isolate themselves until they have fully recovered.
Although the majority of new monkeypox cases have been seen in gay or bisexual men, experts caution that anyone is at potential risk.
People normally become infected with the monkeypox virus through contact with the skin lesions or bodily fluids of infected animals or humans or through contact with materials contaminated with the virus.
The disease is commonly found in parts of central and west Africa.
Monkeypox, which is related to smallpox, has milder symptoms.
Some of those symptoms include fever, chills, rash and aches, before lesions develop.
Reuters and The Associated Press contributed to this report.