CDC raises the alarm about monkeypox after a man is hospitalized with the rare virus in Dallas

• A US resident who traveled from Nigeria back home is hospitalized with monkeypox in Dallas.
• Due to mask-wearing protocols, the risk he transmitted the illness to other travelers is low.
• Monkeypox is rare but can be deadly, especially in people with weakened immune systems.

A US man has been hospitalized in Dallas after returning to the states from Nigeria, the Centers for Disease Control and Prevention and the Texas Department of State Health Services announced Friday.

The man left Lagos, Nigeria, on July 8 and arrived into Atlanta on July 9. He took another flight from Atlanta to Dallas July 9.

Due to mask-wearing protocols in airports and on airplanes, health officials say the risk he spread the virus - which transmits through respiratory droplets - to other travelers is low.

Still, the CDC and local health departments are getting in touch with people who may have been in contact with the man.

Smallpox is rare but in Africa it can kill as many as 1 in 10

Monkeypox is rare, but can be serious. The strain the man became infected with, one mostly seen in West Africa, kills one in 100. In Africa, the disease may lead to death in as many as one in 10, the CDC says.

People with smallpox first tend to develop flu-like symptoms and lymph node swelling before experiencing a widespread rash on the face and body. They develop lesions that progress through various stages before falling off. Time between infection symptoms can range between five and 21 days, and the illness itself lasts between two and four weeks.

While there's no proven, safe treatment for the infection, clinicians in the US may use off-label treatments like the smallpox vaccine and antivirals to help control or prevent a potential outbreak.

There have been several monkeypox outbreaks in Africa since 1970, and one large outbreak in the US in 2003 after the virus spread from imported African rodents to pet prairie dogs. The disease seemed to be dormant in Nigeria for nearly 40 years before re-emerging in 2017. CDC experts have been working to suppress it since then.

Before the current case, at least six known people brought monkeypox from Nigeria to other countries including the UK, Israel, and Singapore.