under the microscope
By Rodney E . Rohde , PhD , MS , SM ( ASCP ) CMSV CM , MBCM , FACSc
Monkeypox : Now What ?
On May 7 , 2022 , the world was alerted to a confirmed case of monkeypox in the United Kingdom . Cases have since occurred globally , from Germany and Spain to the U . S . and Canada . The global outbreak has expanded to almost 50,000 cases in over 99 locations with 92 locations from non-endemic areas . The U . S . has now exceeded 20,000 cases in all 50 states and territories . Currently , there have been 12 deaths globally but none in the U . S .
Endemic to Central and West Africa , monkeypox was first discovered in 1958 in monkeys kept for research in the Democratic Republic of the Congo ( DRC ). The first human case was not reported until 1970 in the DRC . Cases have appeared since that time throughout Africa and beyond , including Singapore , the U . K , Israel and the U . S . Most infections occur in people who live , have travelled to , or have been in contact with individuals or animals from endemic regions . For example , in 2003 more than 70 people in the U . S . fell ill with monkeypox after handling prairie dogs that were co-housed with infected Gambian pouched rats and dormice imported from Ghana . However , infections don ’ t always follow this transmission pattern , as evidenced by the current spread of monkeypox among people who have not travelled to endemic countries or been in contact with those known to be infected with monkeypox .
In the current 2022 outbreak , the primary transmission route has been concentrated in men who have sex with men ( MSM ). To date , it is unclear , and remains under investigation , whether monkeypox can be transmitted specifically through sexual transmission routes . Clearly , monkeypox is transmitted by close contact via skin to skin or by contact of skin with fomites ( linen , clothing , etc .). Respiratory transmission is possible , but it is not an effective or efficient vehicle for spread of the virus .
In its August 26 , 2022 , Morbidity and Mortality Weekly Report , the Centers for Disease Control and Prevention ( CDC ) reported the High-Contact Object and Surface Contamination in a Household of Persons with Monkeypox Virus Infection — Utah , June 2022 . The two persons with monkeypox were confirmed positive by real-time polymerase chain reaction ( PCR ) and lived together without other housemates . Both persons experienced prodromal symptoms ( e . g ., fatigue and body aches ). Eight days of symptoms , patient A experienced penile lesions ; lesions spread to the lips , hands , legs , chest , and scalp by day 10 . Patient B experienced prodromal symptoms eight days after illness onset of patient A ; patient B experienced a lesion on the foot which spread to the leg and finger by day 11 . Although both patients had lesions in multiple anatomic areas , the overall number of lesions was small , and lesions varied in presentation from “ pimple-like ” or ulcerated , to characteristically well-circumscribed and centrally umbilicated . Both patients had mild illness . The time from symptom onset to resolution was approximately 30 days for patient A and approximately 22 days for patient B .
The Utah Department of Health and Human Services ( UDHHS ) assessed the presence and degree of surface contamination of
household objects contacted by monkeypox patients by swabbing objects in the home of the patients . The patients identified high-contact objects and surfaces for sampling ; the patients also described “ normal types ” of cleaning and disinfection activities performed within the home during their illness and locations within the home where they spent substantial amounts of time while ill . The patients had isolated at home for 20 days before their home was entered for sampling . The patients were still symptomatic at the time UDHHS collected specimens from their home . The temperature in the two-story home ranged from 69 degrees F ( 20.6 degrees C ) to 75 degrees F ( 23.9 degrees C ) during isolation .
Specimens were obtained from 30 objects in the home and tested for both non-variola Orthopoxvirus and West African Monkeypox virus – specific real-time PCR assays . Viral culture was only pursued if the qualitative PCR result was positive . This activity was reviewed by the CDC and was conducted consistent with applicable federal law and CDC policy . Among the 30 specimens , 21 ( 70 percent ) yielded positive real-time PCR results , including those from all three porous items , 17 of 25 ( 68 percent ) nonporous surfaces and one of two mixed surface types .
Both patients reported showering and using hand hygiene regularly while also doing the laundry ( including bedding , etc .) weekly and cleaning most high contact surfaces “ often ” during their illness . However , the cleaning spray used was not listed on the Environmental Protection Agency ( EPA )’ s List of Disinfectants for Emerging Viral Pathogens .
Monkeypox virus DNA was detected from many objects and surfaces indicating that some level of contamination occurred in the household environment . However , by not detecting viable virus suggests that virus viability might have decayed over time or through chemical or environmental inactivation . Although both patients were symptomatic and isolated in their home for more than three weeks , their cleaning and disinfection practices during this period might have limited the level of household contamination . These data are limited , and additional studies are needed to assess the presence and degree of surface contamination and investigate the potential for indirect transmission of monkeypox virus in household environments . Persons living in or visiting the home of someone with monkeypox should follow appropriate precautions against indirect exposure and transmission by wearing a well-fitting mask , avoiding touching possibly contaminated surfaces , maintaining appropriate hand hygiene , avoiding sharing eating utensils , clothing , bedding , or towels , and following home disinfection recommendations .
Rodney E . Rohde , PhD , MS , SM ( ASCP ) CM SVCM , MBCM , FACSc , serves as chair and professor of the Clinical Laboratory Science Program at Texas State University . Follow him on Twitter @ RodneyRohde / @ TXST _ CLS , or on his website : http :// rodneyerohde . wp . txstate . edu /