By Francisco R. Velázquez, M.D., S.M., FCAP
What is monkeypox and where does it come from? It sounds a little silly and foreign, and after what we’ve experienced with COVID-19, maybe a little scary. Like any disease, it does have risks we need to be aware of, but monkeypox is not new. We know where it comes from, how to recognize it and how to treat it.
Since May 13, 27 nonendemic countries have reported a total of 780 laboratory-confirmed cases to the World Health Organization, as of June 2. The vast majority are European nations like the United Kingdom and Spain. The United States became one of the 27 countries on May 18, when suspected monkeypox was reported in a Massachusetts resident. As of Tuesday, we have 35 confirmed cases in 15 states, including Washington.
This is not the first time we have had cases diagnosed in the U.S. In 2003, we had an outbreak in which 47 people, mainly in the Midwest, were infected through contact with domesticated prairie dogs who were exposed to an infected Gambian pouched rat imported from Ghana while they shared space in a pet store. Last year, the U.S. had two cases in travelers from Nigeria. No transmission was identified from these cases.
What is different now? There are several differences. For example, there is a high number of countries and cases reported in nonendemic areas. Also, there is an unusually high number of suspected cases due to person-to-person transmission, as opposed to animal-to-human transmission.
Monkeypox is considered “endemic” in 12 West and Central African nations, including the Democratic Republic of the Congo, where most of the world’s cases are reported, particularly near the rainforests. The disease has become more common over the years in areas where people are dependent on hunting squirrels and other rodents as a source of protein. The natural reservoir, or source, of monkeypox has not been definitively established, but is most likely rodents. Infections have been identified in squirrels, rats, mice, prairie dogs, monkeys and humans. Despite the name, it is not known if primates such as monkeys are more than incidental hosts.
So, why is it called monkeypox? The virus was first identified in 1958 in research monkeys at Statens Serum Institute, a facility in Copenhagen, Denmark. The first patient was a child from DRC who was diagnosed with the disease in 1970. Monkeypox is classified as a zoonosis, which means most cases of transmission were to people from infected animals and is a much less severe cousin of smallpox. In endemic areas, less than 28% of the cases are confirmed person-to-person transmission. Once infected, the incubation period is usually six to 13 days but can range from five to 21 days. Infected individuals may be contagious one day before the rash appears and for up to 21 days after until the scabs fall off the rash. The initial symptoms are flu-like, followed by swollen lymph nodes and a rash that appears as sores, bumps or fluid-filled bumps or pustules. The rash usually involves the extremities but can involve the head and torso. In some of the recent cases, the rash has been confined to the genital areas.
Monkeypox usually resolves within two to four weeks, and the skin lesions resolve in 14 to 21 days; although in many patients, hypo- or hyperpigmented lesions can be seen for up to two years. The disease can be serious, especially for immunocompromised people, children and pregnant people. Cases associated with the West African species have a lower mortality rate of around 1%, while cases of the Central Basin (Central African) type have a higher mortality, up to 11% in unvaccinated children. Most of the cases in the current outbreak seem to be associated with the milder West African virus group.
At this point, it is important to remember this is a rare disease in this country.
It is also difficult to get infected, and casual contact with an infected person typically does not result in transmission. Sources of transmission include contact with infected lesions, contaminated bedding or towels, or face-to-face exposure to respiratory droplets. You can kill the virus on surfaces using common household disinfectants.
Being aware of the signs and symptoms – particularly if there is a history of recent travel to an endemic area, unexplained rashes, or recent intimate contact with a person with monkeypox – is critical to preventing the spread. While this virus is not a sexually transmitted infection, the recent surge in cases around the world appears to have been spread among men who have sex with men. Although vaccination to prevent monkeypox is not recommended for the public, certain people who have had direct exposure may be advised to get the vaccine.
At this time, you shouldn’t worry. The transmission numbers are still small, and we have not seen a case in Spokane County.
But it is important to be aware of the symptoms, identify people who were exposed, and reach out to your provider if you have any questions or concerns.
Francisco R. Velázquez, M.D., S.M., FCAP, is the health officer for Spokane Regional Health District.