Red Book Online Outbreak: Mpox

Sept 2024: Pediatricians should be alert for the signs and symptoms of mpox in children and adolescents traveling from the Democratic Republic of Congo or a country where mpox is occurring in the last 21 days, or children who have contact with persons who have recently been in a country where mpox transmission is occurring.

Overview

Mpox (formerly known as monkeypox) virus has two distinct genetic clades (subtypes), I and II, which are endemic to central and west Africa, respectively. The Centers for Diseases Control and Prevention (CDC) is currently monitoring increasing reports of mpox in the Democratic Republic of the Congo (DRC) since 2023. These cases involve a virus type (clade I) that can cause more infections that are severe than the virus type that has been causing the ongoing 2022 global mpox outbreak (clade II).

Both clade I and clade II mpox can lead to a large number of lesions distributed across the body and a need for inpatient clinical management. While clade II mpox is self-limited in immunocompetent persons, clade I mpox may cause severe disease in a higher proportion of patients, with case fatality rates ranging from 1.4% to over 10% for historic outbreaks. It may also spread more easily among household contacts.

Clade I Mpox Outbreak in Central Africa

While clade I mpox is endemic in DRC, many of these cases are being reported in new provinces and urban areas where mpox does not normally occur. In addition, the suspected cases and deaths include high numbers of children. There have never been documented cases of clade I mpox within the United States. CDC is coordinating with state, tribal, local, and territorial jurisdictions, other federal agencies, and private partners to ensure that the United States is prepared if clade I mpox begins to spread globally. 

Since mpox was first recognized in the 1970s, the majority of cases in DRC have been in children. Transmission often occurs through contact with wild animals that carry the virus, or through close, prolonged contact with cases in a household. In the current outbreak in DRC, CDC is not aware of any confirmed reports of mpox spreading among children in schools. However, spread within households is possible, and is usually associated with close, prolonged contact with ill family members or shared spaces. Malnutrition and other diseases may also be contributing to the high rates of severe illness being observed. 

The potential risk of clade I mpox cases in children in the United States remains very low. There are no animal reservoirs of mpox in the United States, and other factors, such as average family size and access to healthcare, are vastly different.

Ongoing Clade II Mpox Global Outbreak

Since the start of the ongoing mpox clade II global outbreak that started in May 2022, there have been 32,063 confirmed cases of mpox and 58 deaths in the US. As of January 10, 2024, CDC is no longer updating the mpox outbreak US case count. There has not been a marked change in weekly or monthly national case counts during the last 6 months. The majority of US cases continue to be in people who are not vaccinated or who have only received one dose of JYNNEOS vaccine (see Vaccination section below). This mpox clade II outbreak is part of a larger global outbreak: 2022-2023 Mpox Outbreak Global Map | CDC Archive.

The risk of children getting infected with mpox clade II virus is low. Of the total 32,063 US mpox cases, 64 cases have been reported in children 0-15 years old and 699 cases have been reported in adolescents/young adults 16-20 years old in the US. More information on mpox clade II outbreak case demographics can be found here: Mpox Cases by Age and Gender and Race and Ethnicity | CDC Archive

Clinical Guidance (Clade I and II)

• Presentation: Mpox should be suspected in patients presenting with a rash consistent with mpox, especially (but not solely) in patients with exposure to someone known to have or suspected to have mpox. Clinical judgement and consultation with an infectious disease specialist and/or your local public health department is important in determining who needs testing, as the overwhelming majority of children who present with a rash will have an alternative etiology.
• The rash associated with mpox produces macules that progress to papules, vesicles, and then pustules that are deep-seated, firm or hard, and well-circumscribed; the lesions may umbilicate or become confluent and progress over time to scabs. Rash may spread to other parts of the body. In classic mpox, lesions on a particular body part are in the same stage. This has not always been the case in the current outbreak, with lesions in varying stages of progression being seen in many patients in the US currently, and lesions may be few in number, and limited to one area.
• Presenting symptoms typically include fever, chills, malaise, sore throat, headache, and new lymphadenopathy, followed by the distinctive rash. In the current outbreak, onset of perianal or genital lesions in the absence of fever or other systemic symptoms or concurrently with systemic symptoms also has been reported. Other symptoms include difficulty swallowing or cough when oropharyngeal lesions are present. Ocular lesions may present with eyelid swelling or crusting.
• The rash associated with mpox can be confused with other diseases that are more commonly encountered in clinical practice (eg, syphilis, herpes simplex virus [HSV], chancroid, varicella zoster, and molluscum contagiosum). In addition, some patients have been coinfected with syphilis or HSV and mpox. A high index of suspicion for mpox is warranted when evaluating patients with a new onset of clinically compatible rash, who present with lesions in the genital/perianal area or for patients who had contact with a suspected or known case of mpox.
• Pediatricians can review the case definition for more information: Mpox Case Definitions | Mpox | Poxvirus | CDC
• Diagnosis: If a patient is suspected of having mpox, the clinician should contact the health department to discuss testing. Testing is performed on skin lesion material (dry swab, swab placed in viral culture media, or crusts) or mucosal lesion material. Testing on blood or other body fluids is not available. For information on testing specimens that will be sent to a Laboratory Response Network (LRN) site see Guidelines for Collecting and Handling Specimens for Mpox Testing | Mpox | Poxvirus | CDC. Clinicians should be aware that false positive tests have occurred in patients (including children) who were at low risk, without a known epidemiological link, and who had a high real-time PCR cycle threshold value; for more information see MMWR.
• Complications: Patients with mpox can develop a variety of complications, including encephalitis, encephalomyelitis, pneumonia, sepsis, hemorrhagic disease, myocarditis, pericarditis, other conditions requiring hospitalization, blindness (secondary to ocular infection), and bacterial skin infections. If the patient is pregnant, there may be complications, including preterm delivery, fetal death, or congenital disease; data are very limited. For more information: Monitoring People Who Have Been Exposed | Mpox | Poxvirus | CDC
• Precautions: Mpox spreads person to person primarily through contact with infectious rashes, prolonged face-to-face contact, or items that previously touched the infectious rash or body fluids. Standard precautions should be applied for all patient care, including for patients with suspected mpox. If a patient seeking care is suspected to have mpox, infection prevention and control personnel should be notified immediately. In the inpatient setting, persons with suspected or confirmed mpox should be placed in a single patient room with a dedicated bathroom. Special air handling for mpox is not required except during aerosol-generating procedures (although airborne isolation is required for some infections associated with rash, such as varicella or measles). Intubation, extubation, and any procedure likely to spread oral secretions should be performed in a negative pressure isolation room. In ambulatory healthcare settings, the lesions of patients with suspected or confirmed mpox should be covered and patients who are at least 2 years of age should be masked. Patients should be put in an exam room promptly. In both inpatient and ambulatory settings, the PPE used by healthcare personnel who enter the patient’s room should include a gown, gloves, eye protection (ie, goggles or face shield), and a NIOSH-approved particulate respirator equipped with N95 filters or higher. For more information: How it Spreads | Mpox | Poxvirus | CDC.
• Infection Prevention and Control: In addition to Standard Precautions, if a patient seeking care is suspected to have MPXV infection, additional infection control precautions should be implemented. Recommendations can be found here: Infection Control: Healthcare Settings | Mpox | Poxvirus | CDC
• Home Isolation: Children and adolescents with mpox who do not require hospitalization should be isolated at home. Infected persons should avoid contact with uninfected people and pets until the rash has resolved, the scabs have fallen off, and a fresh layer of intact skin has formed. When possible, the number of caregivers should be limited to one person who has been educated about infection prevention strategies. Caregivers should wear a respirator or well-fitting face mask, cover areas of broken skin with bandages and clothing to the extent possible and avoid direct skin-to-skin contact with the rash. During interactions with uninfected caregivers, children over 2 years of age with mpox should wear well-fitting source control (eg, a medical mask) when possible. Caregivers assisting with changing bandages or clothes covering the rash should wear gloves to avoid infection, dispose of gloves after use and perform handwashing. For questions about home isolation for individual patients and circumstances, discussion with local or state health departments is recommended. For more information: Isolation and Infection Control: Home | mpox | Poxvirus | CDC  

Risk Mitigation

• Exposure Reduction: Pediatricians should educate patient and families traveling to the DRC or neighboring countries about how to avoid exposure to mpox:
  • Avoid close contact with people who are sick with signs and symptoms of mpox, including those with skin or genital lesions.
  • Avoid contact with wild animals (alive or dead), such as small mammals, including rodents (rats, squirrels), and non-human primates (monkeys, apes).
  • Avoid contact with contaminated materials used by people who are sick (such as clothing, bedding, or materials used in healthcare settings) or that came into contact with wild animals.
  • Avoid eating or preparing meat from wild animals (bushmeat) or using products (creams, lotions, powders) derived from wild animals.
  • Some persons aged 18 and older may qualify for mpox vaccine before travel.
• Vaccination: CDC recommends that people whose jobs (clinical or research laboratories and certain healthcare and public health team members) may expose them to orthopoxviruses, such as mpox, get vaccinated with JYNNEOS or ACAM2000 to protect them from an orthopoxvirus infection. At this point, vaccination is not recommended for most healthcare providers. ACIP recommends vaccination with the 2-dose JYNNEOS vaccine series for persons aged 18 years and older at risk for mpox. The standard regimen for JYNNEOS vaccine is a 0.5 mL dose administered subcutaneously followed by a second dose 28 days later.  Persons at risk:
  • Gay, bisexual, and other men who have sex with men, transgender or nonbinary people who in the past 6 months have had one of the following:
    • A new diagnosis of ≥1 sexually transmitted disease
    • More than one sex partner
    • Sex at a commercial sex venue
    • Sex in association with a large public event in a geographic area where mpox transmission is occurring
    • Sexual partners of persons with the risks described above
    • Persons who anticipate experiencing any of the above
• Post-exposure Prophylaxis: Children and adolescents who have had close physical contact with someone with a known or suspected mpox infection may qualify for post-exposure prophylaxis.
  • Public health officials may recommend vaccine for contacts of mpox cases, especially those that are found to be at high risk. Healthcare providers who have unprotected, high risk contact with patients with mpox may be eligible for post-exposure prophylaxis in consultation with public health authorities.
  • JYNNEOS vaccine may be recommended for and given to children <18 years of age for post-exposure prophylaxis under an emergency use authorization protocol. Clinicians should discuss use of vaccine in a child as post-exposure prophylaxis with the state or local health department. Only subcutaneous administration of JYNNEOS vaccine is authorized for children <18 years of age.
  • Vaccinia immune globulin is available through an IND protocol for the potential prevention of mpox, but its effectiveness is unknown. Vaccinia immune globulin is an alternative to vaccine for post-exposure prophylaxis, especially in children <6 months of age.
  • Tecovirimat (TPOXX, ST-246) may be considered for post-exposure prophylaxis when vaccine is contraindicated; its effectiveness is unknown. Information about tecovirimat availability through the STOMP study or EA-IND: Tecovirimat (TPOXX) IND Information (cdc.gov)
• Treatment: Mpox is typically a self-limiting condition. Some patients are at higher risk for severe disease and should be considered for treatment on a case-by-case basis, including immunocompromised patients, pregnant or breastfeeding persons, children under 1 year, and those with atopic dermatitis or another condition that affects skin integrity. In addition, those with complicated or severe disease, or with lesions in the areas that might result in severe sequelae, including scarring and strictures (eye, mouth, genitals, or anus/rectum), should be considered for treatment. Tecovirimat is considered first-line treatment for those patients who require treatment. Additional potential treatments for mpox in children include tecovirimat, vaccinia immunoglobulin, brincidofovir, and cidofovir. For more information: Clinical Considerations for Mpox in Children and Adolescents in the U.S. | Mpox | Poxvirus | CDC
• Reporting and assistance: Clinicians should report cases to state or local health departments (State Contacts) as soon as mpox is suspected. If you have a patient that meets the probable or confirmed case definition, the health department will notify CDC. For more information: Case Reporting Recommendations for Health Departments | mpox | Poxvirus | CDC
• Management of exposed newborns: Mpox Outbreak - Special Populations | Red Book Online | American Academy of Pediatrics (aap.org)

Resources

• For more information see the Red Book chapter: Mpox
• Health Alert Network (HAN) - 00513 | Mpox Caused by Human-to-Human Transmission of Monkeypox Virus in the Democratic Republic of the Congo with Spread to Neighboring Countries (cdc.gov)
• Frantzis I, Ungar SP, Soma VL, et al. Mpox in Children: 3 Cases. Pediatrics. 2024;153(2): e2022061047