NWe want to maximize the distribution of vaccines to those we know would benefit”said Jennifer McQuiston, a manager at the Centers for Disease Prevention and Control (CDC), on Monday. “That is, those who have been in contact with a known monkeypox patient, such as caregivers, very close personal contacts, especially those at risk of developing a severe case of the disease”she said at a press conference.
One case has been confirmed in Massachusetts and four others are about to be analyzed, but considered very probable (one in New York, one in Florida, two in Utah). All are men who have traveled outside the United States.
What intrigues and worries experts is the simultaneous appearance of cases in many countries
The disease, a less dangerous cousin of smallpox eradicated for about forty years, begins with a high fever and quickly evolves into a rash, with the formation of scabs.
What intrigues and worries the experts is the simultaneous appearance of cases in many countries, particularly in Europe, without them being associated with returns from African countries where the disease is endemic.
US authorities confirmed that the sequencing of the virus detected in Massachusetts matched that identified in a patient in Portugal, and that the strain was the one present in West Africa, the less serious of the two in circulation.
Most infected people recover spontaneously within two to four weeks, without specific treatment. The American authorities are still preparing the response.
Two vaccines to prevent the spread
Two smallpox vaccines authorized by the United States Food and Drug Administration (FDA) can be used. The first, ACAM2000, is a live attenuated vaccine, not recommended for immunocompromised people. The United States has 100 million doses. Due to side effects “potentially significant”its large-scale distribution would require “a real conversation”said Jennifer McQuiston.
The second, Jynneos, is also a live, but non-replicating, vaccine and therefore considered safer. The United States only has 1,000 doses, but that number should “increase rapidly in the next few weeks”, according to the manager.
According to the same source, data show that these two vaccines can help prevent the development of the disease if they are administered quickly after exposure. She also stressed that the risk of contamination remained generally low for the population.
Immunocompromised and eczema patients among populations at risk
Among the populations most at risk are immunocompromised people and those with particular skin conditions such as eczema, according to John Brooks, an epidemiologist.
Rashes caused by monkeypox lead to lesions that may be centered in certain areas or spread all over the body. In some cases, during the first phase of the disease, the rashes may appear on the genital or perianal areas.
Transmission of the virus occurs through prolonged skin-to-skin contact with a person who has an active lesion, or through respiratory droplets from someone with oral lesions and in close proximity to another person for some time.
While scientists are concerned that the growing number of cases could potentially indicate a new type of transmission, there is so far no concrete evidence supporting this theory, said Jennifer McQuiston.
More spread within the gay community?
Thus, the increase in the number of cases could be linked to certain propagative events within the gay community, explaining a higher prevalence among homosexual and bisexual men.
But that doesn’t mean “in any way”according to John Brooks, that “the current risk of exposure to monkeypox only affects the gay and bisexual community”.
The CDC is also developing treatment guidelines to enable the deployment of the antivirals tecovirimat and brincidofovir, both of which are already licensed for the treatment of smallpox.