The World Health Organization said the expanding monkeypox outbreak in more than 70 countries is an "extraordinary" situation that now qualifies as a global emergency, a declaration Saturday that could spur further investment in treating the once-rare disease and worsen the scramble for scarce vaccines.
The infections have raised alarm, because monkeypox is usually not found outside Africa, but since May, authorities have detected dozens of cases in Europe, North America and elsewhere.
In the U.S., nearly 4,000 cases of monkeypox have been cited as of Friday, USA TODAY reported. Nearly every state in the U.S. has reported monkeypox cases.
The virus is called monkeypox because it was first identified in laboratory monkeys in 1958, Nature reported.
Human monkeypox was first found in the Democratic Republic of the Congo in 1970.
The first U.S. case is a Massachusetts man who tested positive May 18 after returning from a trip to Canada, the CDC said.
Gay, bisexual or other men who have sex with men are at highest risk for monkeypox in this outbreak, health officials say.
Monkeypox is usually passed to humans from rodents and primates, through bites, aerosol transmission or contact with infected fluids.
Person-to-person transmission is usually through close contact with respiratory secretions, inflected skin lesions or recently contaminated objects, according to the World Health Organization.
The CDC adds that person-to-person transmission can occur from skin-to-skin contact such as hugging and massaging, as well as sex. This includes contact with fabrics and objects used during sex that haven't been disinfected."
Smallpox vaccinations are about 85% effective in preventing monkeypox infection, WHO said.
The incubation period, the time between infection and symptoms, is usually six to 13 days but can be five to 21 days.
Symptoms of monkeypox include:
- Muscle ache
- Swollen lymph nodes
The monkeypox illness lasts two to four weeks. Within one to three days of infection, a patient will develop a facial rash that spreads to other parts of the body, the CDC said. The fluid-filled lesions go through a series of stages before drying out and falling off.
Monkeypox has two main strains:
- Congo, which has a mortality rate of up to 10% and is considered the more severe of the two.
- West African, with a mortality rate of about 1%. Cases in the U.K. have been identified as West African.
CONTRIBUTING Celina Tabor, Joel Shannon, Elizabeth Weiss, USA TODAY
SOURCE USA TODAY Network reporting and research; Associated Press; Centers for Disease Control and Prevention; World Health Organization