The current monkeypox outbreak is more widespread than previous outbreaks outside Africa and should prompt all doctors to be alert to the possibility that patients presenting with febrile illness and rash may be infected, according to the authors of a new commentary from the Johns Hopkins Center for Health Security at the Bloomberg School of Public Health. The authors also note that a significant number of these new cases have occurred among men who have sex with men (MSM), although the cause is unclear. These and other important facts about the current monkeypox outbreak are explained in a new commentary published in the Annals of Internal Medicine .
Currently, several dozen cases of monkeypox have been reported in Europe, the United Kingdom and North America, worrying epidemiologists and public health experts around the world. What distinguishes these cases (all occurring outside the virus endemic region) is that human-to-human transmission is occurring, and most cases are apparently not related to travel from an endemic country, with the appearance of multiple , until now. unlinked clusters. Furthermore, a significant proportion, although not all, of cases occur in MSM, and many of these cases are diagnosed in sexually transmitted infection (STI) clinics.
The authors emphasize that this does not necessarily mean that monkeypox is transmitted sexually.
As a member of the orthopox viral family , of which smallpox is also a part, it is possible that the increase in monkeypox outbreaks in recent years is related to the decline in population immunity to smallpox over the course of the year. time. Smallpox vaccination could prevent cases, and smallpox antivirals could also treat monkeypox cases.
Monkeypox usually presents with fever and rash that starts in the mouth, then moves to the face, followed by the extremities, including the palms and soles in a telltale centrifugal pattern.
Primary care doctors, emergency room doctors, dermatologists, and those working in STI clinics may be the most likely to identify new monkeypox patients if they continue to appear. Doctors who suspect monkeypox should alert state health officials to initiate testing, such as a commercially available test for monkeypox.
Diagnosis
Given the current outbreak, clinicians caring for patients with febrile illness and new-onset rash should consider monkeypox, especially if lymphadenopathy is also present. The rash usually begins in the mouth, then moves to the face, followed by the extremities (including the palms of the hands and soles of the feet) in a centrifugal pattern .
Definitive diagnosis is achieved by polymerase chain reaction testing of skin lesions or fluid. These tests are available at state public health laboratories. There is no commercially available test.
Treatment
Although there is no standard treatment for monkeypox, smallpox antivirals with activity against smallpox virus, such as cidofovir, brincidofovir, and tecovirimat, have activity against monkeypox. The latter two drugs are approved by the United States Food and Drug Administration (FDA) for use in the treatment of smallpox. Such medications will most likely be reserved for the treatment of severe cases or in immunocompromised people and will be accessed through a public health department or the CDC.
Prevention
Smallpox vaccines are effective in preventing monkeypox and as post-exposure prophylaxis. A newer generation smallpox vaccine, JYNNEOS (Bavarian Nordic), has an FDA indication for the prevention of monkeypox, and the older generation ACAM2000 can be used off-label for the same purpose.
In previous outbreaks, vaccination of close contacts has successfully limited transmission. Administration of the prophylactic vaccine as soon as immediately after possible exposure may abort the infection or significantly attenuate it. In cases where smallpox vaccination is contraindicated, vaccinia immune globulin may be administered as an alternative post-exposure prophylactic agent.
Uncertainties related to the current outbreak
At the time of writing, several dozen cases of monkeypox have been reported in Europe, the United Kingdom, and North America. What distinguishes these cases, all of which are outside the virus-endemic region, is that human-to-human transmission is occurring, and most cases are apparently not related to travel from an endemic country and the emergence of multiples, so far. unlinked clusters. This suggests that undetected chains of transmission have occurred.
Another unusual feature is that a significant proportion—although not all—of the cases that have been recognized are in men who have sex with men (MSM), and many of these cases are being diagnosed in sexually transmitted infection (STI) clinics. . This suggests that the virus may be exploiting specific social networks. The virus may or may not be spreading sexually in this group and may instead rely on skin-to-skin contact and/or respiratory droplet transmission. It is noteworthy that the latter has been identified as a route of meningococcus transmission in MSM groups.
The most pressing immediate challenge is to unravel the epidemiology of this outbreak. What is driving this outbreak, which is much larger and more widespread than previous monkeypox outbreaks outside Africa? Initial genetic analysis has not reported any genetic changes believed to increase transmissibility. Is the virus spreading through a social network? Was transmission facilitated by grouping into specific events? Rapid case investigations and case-control studies are essential to understanding this and are underway.
