Monkeypox is spreading rapidly across the United States. There are steps that every hospital and every medical practice need to take now to protect patients and healthcare workers. As of yesterday, there were 6,326 known cases and undoubtedly considerably more that have gone undiagnosed. Infected patients will be presenting to your hospital, office practice, and emergency department in the next few weeks.
Where did monkeypox come from?
Monkeypox is a type of orthopoxvirus that is related to smallpox. It was first found in monkeys in a Danish research lab in 1958. The virus is not unique to monkeys, however, and has since been found in various mammalian species in Western Africa. Humans have sporadically become infected after contact with infected animals. Although most human cases have been reported in Africa, there have been occasional clusters of cases in other countries over the past 20 years.
One of the most notable clusters occurred in the United States in 2003 when 47 Americans became infected with monkeypox that originated from an infected giant Gambian rat that had been imported from West Africa for sale as an exotic pet. The rat then infected a group of captive prairie dogs that were also sold. Of the 47 cases, all but one person acquired monkeypox directly from an infected animal. In only one case was there human-to-human transmission (from a child to mother).
In July 2021, a traveler from Nigeria was diagnosed with monkeypox in Texas. In November 2021, a second travel-related case was diagnosed in Maryland. The current outbreak began on May 7 2022 when a travel-related case was diagnosed in the United Kingdom. Later that month, cases were diagnosed in Massachusetts and New York. Since that time, the number of cases has been growing exponentially. Because of lack of familiarity with the disease and difficulty in obtaining diagnostic tests, it is likely that most cases initially went undiagnosed and that the true number of U.S. cases is much higher.
How is it spread?
Because the initial cases were reported in gay men, there is a misconception that monkeypox is a sexually-transmitted disease, like syphilis or HIV. It is not. Monkeypox is primarily spread by skin-to-skin contact, similar to MRSA. Thus, the initial cases occurred in gay men not because they had sex with other men but because they had close skin contact with infected men. Although the virus can also be spread by respiratory secretions, it is not as contagious as other respiratory viruses, such as COVID. Therefore, it requires closer and/or more prolonged exposure for airborne transmission. However, because it can be spread by both contact and airborne routes, both contact and airborne isolation is recommended for inpatients. Other points to know about monkeypox transmissibility:
- It can be transmitted to and from pets
- Bed linens, clothing, eating utensils, and drinking glasses can be infectious
- Infected persons remain contagious until scabs have all crusted over and a layer of new skin has developed
- Usual hospital disinfectants can eliminate the virus
- The average incubation period is 7 days and persons can be contagious during the incubation period
Signs, symptoms, and diagnosis
As of today, most cases have been in men who have sex with men. However, since monkeypox virus is spread by skin contact (rather than sexual contact), the demographic of infected people is expected to rapidly change in the next few weeks. A person does not have to be gay or to even have sex with another person to become infected. Common signs and symptoms reported in a recent article in the New England Journal of Medicine include:
- Rash – 95% (with 64% having <10 lesions)
- Anogenital – 73%
- Trunk or limbs – 55%
- Face – 25%
- Palms or soles – 10%
- Fever – 62%
- Lethargy – 41%
- Myalgia – 31%
- Headache – 27%
- Pharyngitis – 21%
- Lymphadenopathy – 56%
Because 98% of the 528 patients reported in this article were either gay or bisexual men, the incidence of anogenital lesions may be higher than in other patients. The rash is most frequently described as vesiculpustular (53%) but can present as a macular rash (4%), multiple ulcers (19%), or single ulcer (11%). Additional photos of the rash can be found on the CDC website.
The diagnosis is made using swabs of skin lesions – preferably 2 swabs, each from a different lesion. Testing is done by orthopoxviral PCR and results can be available in 2-3 days. Specimen handling procedures can vary from lab to lab so be sure to follow specific instructions from the lab that the sample will be sent to. Until recently, testing was only available through the CDC and results could take 1-2 weeks. Now, testing is available through local health departments as well as several commercial labs making it possible to submit specimens as a regular send-out test from U.S. hospitals. Serology testing is also available through the CDC but the turn around time is 14 days.
In cases reported during this outbreak, the mortality rate is low and in most people, the disease is self-limited and of mild-moderate severity. Consequently, to date, only a minority of patients receive anti-viral treatment (5% in the New England Journal of Medicine study). Certain patients are at higher risk of severe disease and these patients should be targeted for treatment:
- Those with severe disease (hemorrhagic disease, confluent lesions, sepsis, encephalitis, or other conditions requiring hospitalization)
- Immunocompromised persons
- Children (particularly those < 8 years old)
- Persons with exfoliative skin disorders (atopic dermatitis, psoriasis, etc.)
- Pregnant or breast-feeding women
- People with monkeypox complications (secondary bacterial skin infection; severe gastroenteritis; bronchopneumonia; etc.)
- Involvement of anatomic areas at risk of permanent injury (eyes, mouth, anus, genitalia, etc.)
The treatment of choice is tecovirimat (TPOXX). This drug is currently only available through the Strategic National Stockpile. Physicians have to contact either their state health department or the CDC (770-488-7100 or email at Poxvirus@cdc.gov). The dose is 600 mg PO BID x 14 days given within 30 minutes after a full meal of moderate/high fat. Drug side effects can include headache and nausea. TPOXX may reduce blood levels of midazolam and may increase levels of repaglinide.
Other treatments that may be effective but have less scientific data to support their use include intravenous Vaccinia immune globulin, cidofovir, and brincidofovir.
There are two vaccines available that are effective against monkeypox.Both of these are live virus vaccines (unlike most routine vaccines such as COVID vaccines or flu shots). The JYNNEOS vaccine contains a live non-replicating virus. The ACAM200 vaccine contains a live replicating virus.
JYNNEOS is given as 2 injections with the second dose given 4 weeks after the first dose. Full immune response develops 2 weeks after the second dose. The most common side effects are fatigue, headache, and myalgias. Unlike ACAM200, the JYNNEOS vaccine is not contraindicated in immunocompromised persons, pregnancy, or HIV infection.
The ACAM200 vaccine contains a live replicating Vaccinia virus that is given as a single dose. Because ACAM200 contains a replicating virus, it is contraindicated in immunocompromised persons, HIV infection (regardless of immune status), pregnancy, persons with heart disease, children < 1 year old, persons with eye conditions requiring topical steroids, and persons with a history of exfoliative skin disorders (eczema, atopic dermatitis, etc.). Although most side effects of ACAM200 are mild, 1 out of every 175 persons receiving it develop myocarditis or pericarditis. It takes 4 weeks for maximal immune development after vaccination.
Both vaccines are available from the Strategic National Stockpile. Because of limited supply (particularly of the JYNNEOS vaccine), widespread vaccination of the public and of most healthcare workers is not currently advised. Currently, the CDC only recommends pre-exposure prophylaxis vaccination for people at very high-risk of exposure (primarily laboratory workers performing diagnostic testing for monkeypox). The CDC anticipates expanding the indications for pre-exposure prophylaxis vaccination to broader populations as supplies of the vaccine increase in the future.
Most monkeypox vaccines are currently being given for post-exposure prophylaxis. When given within 4 days of exposure, vaccination can prevent the disease and when given between 4-14 days after exposure, vaccination can reduce the severity of monkeypox infection. Persons who should be prioritized for vaccination include:
- Known contacts who are identified by public health via case investigation, contact tracing, and risk exposure assessments
- Persons with a sexual partner in the past 14 days who was diagnosed with monkeypox
- Persons who have had multiple sexual partners in the past 14 days in a jurisdiction with known monkeypox
- Healthcare workers with a high risk exposure such as:
- Unprotected contact with skin, lesions, or bodily fluids of a patient with monkeypox
- Aerosol-generating procedures without N-95 mask and eye protection
Healthcare workers with an intermediate risk exposure should be offered post-exposure vaccination on a case-by-case basis and after discussion of the risks and benefits with the exposed healthcare worker. Intermediate risk exposures include: (1) being within 6 ft of an infected unmasked patient for more than 3 hours when the healthcare worker was not wearing a mask and (2) contact with patient’s clothing, skin lesions, or soiled linens while wearing gloves but not wearing a gown.
Healthcare workers with a low risk exposure generally do not require post-exposure vaccination. Low risk exposures include: (1) entering an infected patient’s room without wearing eye protection, (2) being in a room with an infected patient while wearing gown, gloves, eye protection and at least a surgical mask or (3) being within 6 feet of an unmasked patient for less than 3 hours without wearing at minimum, a surgical mask. Additional information about managing exposed healthcare workers can be found on the CDC website.
Isolation recommendations for infected outpatients
The vast majority of people infected with monkeypox can be treated as an outpatient. In order to control the spread of monkeypox in the community, it is essential that infected persons adhere to proper isolation procedures at home for the duration of infectivity. Infected persons remain contagious for 2-4 weeks. Isolation can be discontinued when until all symptoms have resolved, including full healing of the rash with formation of a fresh layer of skin in areas of vesicles and ulcers. Isolation practices include:
- Remain in the home with no contact with other people
- Avoid close physical contact, including sexual and/or close intimate contact, with other people.
- Avoid sharing utensils or cups. Items should be cleaned and disinfected before use by others.
- Do not share items that will be worn or handled with other people or animals.
- Wash hands often with soap and water or use an alcohol-based hand sanitizer, especially after direct contact with the rash.
- Avoid contact with pets
- Launder and disinfect items that have been worn or handled and that have been touched by a lesion
- Do not dry dust or sweep as this may spread the virus
- Do not wear contact lenses (because of risk of spreading the virus to the eyes)
- Clean and disinfect surfaces with an Environmental Protection Agency-registered disinfectant. If other household members are responsible for cleaning, they should wear a medical mask and disposable gloves, at a minimum
- If the infected person must leave home for medical care or for an emergency, cover the lesions, wear a well-fitting mask, and avoid public transportation
Infection control in the outpatient office
Although not as contagious as COVID, there is still a risk of an outpatient with monkeypox infecting other patients or healthcare workers. All employees of outpatient medical practices need to be familiar with monkeypox infection control practices to minimize the risk of spreading the infection. Specific measures include:
- Utilize telemedicine for patients known or suspected to have monkeypox
- If using pre-registration procedures in advance of patients arrival to the office, include questions about monkeypox signs and symptoms
- Place patients with known or suspected infection in a private exam room with the door closed. These patients should be escorted from the building entrance directly to the exam room and should not wait in a waiting area
- Have patients with known or suspected infection wear a surgical face mask with areas of skin rash covered
- Healthcare workers entering an exam room of a patient with known or suspected infection should wear a disposable gown, gloves, eye protection, and an N-95 mask
- Use disposable paper exam table drapes and patient gowns. Dispose of these materials using medical waste trash bags and do not shake out gowns or drapes
- When the patient leaves, sanitize the room surfaces. Most standard hospital disinfectants will suffice. A list of cleaning products can be found on the Environmental Protection Agency website.
Infection control in the hospital
Only a small minority of patients will require admission to the hospital. Some of the indications for admission include pain management (such as severe anorectal pain), soft-tissue superinfection, pharyngitis limiting oral intake, eye lesions, acute kidney injury, myocarditis, and public health infection-control purposes. Infection control measures for hospitalized patients include:
- Place patients with known or suspected infection in a private room with private bathroom and with the hallway door closed (negative airflow is not required)
- Transport and movement of the patient outside of the room should be limited to medically essential purposes
- When patients must be transported outside of their room, they should wear a medical mask and have any exposed skin lesions covered with a sheet or gown
- Healthcare workers should wear a disposable gown, gloves, eye protection, and an N-95 mask
- If aerosol-generating procedures are to be performed (e.g., intubation or bronchoscopy), use an airborne isolation room
- Environmental services such as dry dusting, sweeping, or vacuuming should be avoided in rooms housing infected patients
- Disposables such as paper towels should be disposed of using medical waste trash bags
- Use surface cleaning products that are believed to be effective for emerging viral pathogens (listed on the Environmental Protection Agency website)
- Do not shake soiled linen, towels, and gowns. Soiled items should be enclosed in a proper laundry bag for transport to the laundry and staff handling laundry from infected patients should wear proper personal protective equipment as recommended by the CDC
- Visitors should be limited to those essential for the patient’s care and wellbeing
Don’t think of monkeypox as a sexually-transmitted disease
Because the current outbreak has so far primarily affected men who have sex with men, monkeypox has developed a mistaken stigmata of being a sexually transmitted disease. It is important that we educate our patients and our co-workers that it is not necessary to have sex with someone to become infected with monkeypox. Measures that prevent spread of HIV and syphilis will not work with monkeypox. Abstinence will not stop it. Condoms will not stop it.
One of our best weapons against monkeypox is education.
August 3, 2022