The Centers for Disease Control and Protection (CDC) and the Texas Department of State Health Services have confirmed the first case of human monkeypox in the US for decades.
On July 15, the patient traveled from Nigeria to Dallas, Texas, where they are currently hospitalized. The CDC is working with local health authorities and the airline in order to track down passengers that came into contact with the US resident – though they believe the risk of transmission to be low, given that masks were mandatory on the flight, limiting the risk of airborne transmission.
As well as being in the same family of viruses as smallpox, the symptoms of monkeypox are similar, though milder. Initial signs include fever, headache, muscle aches, backache, swollen lymph nodes, chills, and exhaustion. After this, a rash may develop, likely beginning on the face before spreading to other parts of the body.
Most patients will develop a mild illness and recover within a few weeks without any treatment, but sometimes it can be fatal. In the strain identified by the CDC, infections will be fatal in about 1 percent of patients, though this grows in patients who are immunocompromised. Between one and ten percent of patients die of the disease during outbreaks, according to the World Health Organization.
Monkeypox was first discovered in 1958 after several outbreaks in monkey populations kept for research in Africa, according to the CDC. The first human case was recorded in the Democratic Republic of Congo (DRC) in 1970. The human version is largely transmitted from animals to humans, rather than human to human. Where it is passed from human to human, it is through contact with lesions and bodily fluids, contaminated materials (e.g. clothing and bedding) as well as respiratory droplets.
The vast majority of cases have taken place in the DRC since, where over a thousand a year have occurred since 1970, the CDC reports. A few smaller outbreaks have taken place across central and western Africa. Only three countries outside of Africa have had cases of the disease – the US had the largest outbreak with 37 confirmed cases in 2003. It was caused by a shipment of animals from Ghana that included some infected with the disease.
"Human-to-human transmission is thought to occur primarily through large respiratory droplets," the CDC writes in their statement. "Respiratory droplets generally cannot travel more than a few feet, so prolonged face-to-face contact is required."
Over the years, there have been several other cases of passengers bringing monkeypox out of Nigeria to their next destination, most of which did not go any further. However, one outbreak has taken place in the United Kingdom, where one patient went on to infect others before it could be contained.