Monkeypox: How do you know if you have it? Signs and symptoms to look for

The Florida Department of Health is investigating a second "presumptive" positive case of monkeypox.

Officials in Broward County are investigating the case, the agency said Monday, stressing that the risk of exposure remains low. The first case was also reported in Broward on Sunday.

Monkeypox is a virus that originates in wild animals like rodents and primates, and occasionally jumps to people. Most human cases have been in central and West Africa, where the disease is endemic. On Monday, a leading adviser to the World Health Organization described the unprecedented outbreak of the rare disease in developed countries as "a random event" that might be explained by risky sexual behavior at two recent mass events in Europe.

In an interview with The Associated Press, Dr. David Heymann, who formerly headed WHO’s emergencies department, said the leading theory to explain the spread of the disease was sexual transmission among gay and bisexual men at two raves held in Spain and Belgium.

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In humans, the symptoms of monkeypox are similar to but milder than the symptoms of smallpox. Monkeypox begins with fever, headache, muscle aches, and exhaustion. According to the Centers for Disease Control and Prevention (CDC), the main difference between symptoms of smallpox and monkeypox is that monkeypox causes lymph nodes to swell (lymphadenopathy) while smallpox does not. 

RELATED: Monkeypox likely spread by sex at 2 raves in Europe, expert says

Experts with the CDC say the illness begins with:

  • Fever
  • Headache
  • Muscle aches
  • Backache
  • Swollen lymph nodes
  • Chills
  • Exhaustion

Within 1 to 3 days (sometimes longer) after the appearance of fever, the patient develops a rash, often beginning on the face then spreading to other parts of the body.

Lesions progress through the following stages before falling off:

  • Macules
  • Papules
  • Vesicles
  • Pustules
  • Scabs

The illness typically lasts for 2−4 weeks. In Africa, monkeypox has been shown to cause death in as many as 1 in 10 persons who contract the disease, according to the CDC.