Mpox Update: Clinical Presentation, Vaccination Guidance, and Management
Following the eradication of smallpox, intermittent small outbreaks of mpox (monkeypox) have occurred with increasing frequency, primarily in endemic regions of Africa. With the rapid spread of mpox around the globe in 2022, we are approaching a second zoonotic pandemic of the 21st century. Given the predominance of cutaneous involvement in mpox, dermatologists should be prepared to recognize the clinical features and manage this increasingly prevalent disease. This article reviews a brief history of the mpox virus, clinical presentation, complications, approach to diagnosis, methods of transmission, infection control recommendations, indications for vaccination, and therapeutic options to inform dermatologists on the frontline of the mpox epidemic.
Practice Points
- Mpox (monkeypox) lesions typically present as well-circumscribed, painful, umbilicated papules, vesicles, or pustules, with recent cases having a predilection for an anogenital distribution accompanied by systemic viral symptoms.
- Health care workers treating suspected or confirmed cases of mpox should be familiar with current guidelines for controlling the spread of mpox, including proper personal protective equipment (gloves, disposable gowns, N95 or equivalent respirators, and eye protection) and indications for vaccination.
JYNNEOS is the preferred vaccine for the prevention of mpox because of its poor ability to replicate in human cells and resultant safety for use in populations that are immunocompromised, pregnant, or have skin barrier defects such as atopic dermatitis, without the risk of myocarditis or pericarditis. However, current supplies are limited. JYNNEOS was specifically studied in patients with atopic dermatitis and has been shown to be safe and effective in patients with a history of atopic dermatitis and active disease with a SCORAD (SCORing Atopic Dermatitis) score of 30 or lower.33 Of note, JYNNEOS is contraindicated in patients allergic to components of the vaccine, including egg, gentamicin, and ciprofloxacin. Although JYNNEOS is safe to administer to persons with immunocompromising conditions, the CDC reports that such persons might be at increased risk for severe disease if an occupational infection occurs, and in the setting of immunocompromise, such persons may be less likely to mount an effective response to vaccination. Therefore, the risk-benefit ratio should be considered to determine if an immunocompromised person should be vaccinated with JYNNEOS.30
The WHO and the CDC do not recommended mass vaccination of the general public for outbreaks of mpox in nonendemic countries, with immunization reserved for appropriate PEP and pre-exposure prophylaxis in intermediate- to high-risk individuals.23,26 The CDC recommends PEP vaccination for individuals with a high degree of exposure that includes unprotected contact of the skin or mucous membranes of an individual to the skin, lesions, body fluids, or contaminated fomites from a patient with mpox, as well as being within 6 feet of a patient during an aerosolization procedure without proper PPE. Following an intermediate degree of exposure, which includes being within 6 feet for 3 or more hours wearing at minimum a surgical mask or contact with fomites while wearing incomplete PPE, the CDC recommends monitoring and shared decision-making regarding risks and benefits of PEP vaccination. Monitoring without PEP is indicated for low and uncertain degrees of exposure, including entering a room without full PPE such as eye protection, regardless of the duration of contact.23,26
Postexposure prophylaxis vaccination should be administered within 4 days of a known high-level exposure to mpox to prevent infection.29 If administered within 4 to 14 days postexposure, vaccination may reduce disease severity but will not prevent infection.34
Pre-exposure prophylaxis is recommended for individuals at high risk for exposure to mpox, including health care workers such as laboratory personnel who handle mpox specimens and health care workers who administer ACAM2000 vaccinations or anticipate providing care for many patients with mpox.34
Management
Most cases of mpox are characterized by mild to moderate disease with a self-limited course. Most commonly, medical management of mpox involves supportive care such as fluid resuscitation, supplemental oxygen, and pain management.6 Treatment of superinfected skin lesions may require antibiotics. In the event of ophthalmologic involvement, patients should be referred to an ophthalmologist for further management.
Currently, there are no FDA-approved therapies for mpox; however, tecovirimat, cidofovir, brincidofovir, and vaccinia immune globulin intravenous are available under expanded access Investigational New Drug protocols.6,35 Human data for cidofovir, brincidofovir, and vaccinia immune globulin intravenous in the treatment of mpox are lacking, while cidofovir and brincidofovir have shown efficacy against orthopoxviruses in in vitro and animal studies, but are available therapeutic options.35
Tecovirimat is an antiviral that is FDA approved for smallpox with efficacy data against mpox in animal studies. It is the first-line treatment for patients with severe disease requiring hospitalization or 1 or more complications, including dehydration or secondary skin infections, as well as for populations at risk for severe disease, which includes immunocompromised patients, pediatric patients younger than 8 years, pregnant or breastfeeding individuals, or patients with a history of atopic dermatitis or active exfoliative skin conditions.36 In this current outbreak, both intravenous and oral tecovirimat are weight based in adult and pediatric patients for 14 days, with the intravenous form dosed every 12 hours by infusion over 6 hours, and the oral doses administered every 8 to 12 hours based on patient weight.37 Tecovirimat generally is well tolerated with mild side effects but is notably contraindicated in patients with severe renal impairment with a creatinine clearance less than 30 mL/min, and renal monitoring is indicated in pediatric patients younger than 2 years and in all patients receiving intravenous treatment.
Conclusion
Given that cutaneous lesions are the most specific presenting sign of mpox infection, dermatologists will play an integral role in identifying future cases and managing future outbreaks. Mpox should be considered in the differential diagnosis for all patients presenting with umbilicated or papulovesicular lesions, particularly in an anogenital distribution. The classic presentation of mpox may be more common among patients who are not considered high risk and have not been exposed via sexual activity. All patients with suspicious lesions should be managed following appropriate infection control precautions and should undergo molecular diagnostic assay of swabbed lesions to confirm the diagnosis. JYNNEOS is the only vaccine that is currently being distributed in the United States and is safe to administer to immunocompromised populations. The risks and benefits of vaccination should be considered on an individual basis between a patient and their provider. Taking into consideration that patients with atopic dermatitis are at risk for severe disease if infected with mpox, vaccination should be strongly encouraged if indicated based on patient risk factors. For atopic dermatitis patients treated with dupilumab, shared decision-making is essential given the FDA label, which recommends avoiding the use of live vaccines.38
The mpox epidemic occurring amidst the ongoing COVID-19 pandemic should serve as a wake-up call to the importance of pandemic preparedness and the global health response strategies in the modern era of globalization. Looking forward, widespread vaccination against mpox may be necessary to control the spread of the disease and to protect vulnerable populations, including pregnant individuals. In the current climate of hesitancy surrounding vaccines and the erosion of trust in public health agencies, it is incumbent upon health care providers to educate patients regarding the role of vaccines and public health measures to control this developing global health crisis.
