key: cord-297853-peqkcix2
authors: Khan, Raymond M.; Al-Dorzi, Hasan M.; Al Johani, Sameera; Balkhy, Hanan H.; Alenazi, Thamer H.; Baharoon, Salim; Arabi, Yaseen M.
title: Middle East respiratory syndrome coronavirus on inanimate surfaces: A risk for health care transmission
date: 2016-11-01
journal: American Journal of Infection Control
DOI: 10.1016/j.ajic.2016.05.006
sha: 
doc_id: 297853
cord_uid: peqkcix2

The Middle East Respiratory syndrome coronavirus (MERS-CoV) has been responsible for multiple health care–associated outbreaks. We investigated whether high-touch surfaces in 3 rooms of laboratory-confirmed MERS-CoV patients were contaminated with MERS-CoV RNA. We found 2 out of 51 surfaces were contaminated with MERS-CoV viral genetic material. Hence, environmental contamination may be a potential source of health care transmission and outbreaks. Meticulous environmental cleaning may be important in preventing transmission within the health care setting.

The Middle East Respiratory syndrome coronavirus (MERS-CoV) has been responsible for multiple health care-associated outbreaks. We investigated whether high-touch surfaces in 3 rooms of laboratoryconfirmed MERS-CoV patients were contaminated with MERS-CoV RNA. We found 2 out of 51 surfaces were contaminated with MERS-CoV viral genetic material. Hence, environmental contamination may be a potential source of health care transmission and outbreaks. Meticulous environmental cleaning may be important in preventing transmission within the health care setting.

© 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

In September 2012, the Middle East respiratory syndrome coronavirus (MERS-CoV) was identified from a patient in Saudi Arabia. As of March 29, 2016, the World Health Organization reported 1,698 laboratory-confirmed MERS cases in 26 countries, with 609 deaths (36%). 1 In its most recent report, the Centers for Disease Control and Prevention has stressed the great importance of personal protective equipment (PPE), source control, and environmental infection control measures to help eliminate the threat of health care-associated outbreaks. 2 Most health care-associated MERS-CoV outbreaks has occurred in Saudi Arabia. Although the precise mechanism of humanto-human transmission has not been elucidated, MERS-CoV can be recovered from plastic surfaces after 48 hours at 20°C and 40% relative humidity (RH), and the virus is viable for 8 hours at 30°C and 80% RH and for 24 hours at 30°C and 30% RH. 3 Further, data from the South Korean outbreak (May 2015) demonstrated that several environmental surfaces frequently touched by laboratory-confirmed MERS patients and health care workers were contaminated by MERS-CoV. 4 Additionally, viral sheading was detected by viral cultures from respiratory secretions up to 25 days postdisease onset. 4 Although MERS-CoV was isolated from numerous high-touch surfaces in 2 Korean hospitals affected by MERS outbreak, 4 such data are lacking in the Middle East. Therefore, the objective of this study was to examine the extent of environmental contamination with MERS-CoV during an outbreak in a Saudi hospital.

The study was performed in the intensive care unit (ICU) at King Abdul-Aziz Medical City, Riyadh, during a MERS-CoV outbreak from September 1-October 5, 2015. The ICU had strict environmental cleaning policies, which included cleaning the rooms at least twice daily using ammonium-based disinfectant and chlorine solution 1:10 or 5,000 ppm, having a checklist, and frequent inspection using fluorescent light or culturing of high-touch areas.

Three negative-pressure rooms of laboratory-confirmed MERS patients (A, B, and C) were selected for this study ( Table 1) . The room temperature was 20.0°C-25.0°C, and RH was 30%-40%. The air exchange rate was 12 per hour, and the pressure gradient between the room and its anteroom ranged from 2.5-12.5 Pa. Sixteen high-touch surfaces were evaluated (Table 2) : 14 in the patients' room (bedrails, mechanical ventilator, ventilator tubing, sink, garbage bin, monitor, intravenous poles, intravenous pumps, telephone, door knobs, floor, drapes-blinds, air conditioning vent, and shelf of the surgical boom) and 2 outside (computer and medical chart). Environmental samples were collected as described by Julian et al. 5 Briefly, a sterile swab premoistened with viral transport media was used to swab each surface (at least 10 cm 2 ) horizontally, vertically, and diagonally for 30 seconds. This procedure was repeated using eluents: 1/4 lactated ringer solution and phosphate buffer solution (PBS). Virus detection was performed using specific real-time reverse-transcription polymerase chain reaction (PCR) assays for the upstream of the envelope gene and the open reading frame 1A. Positive tests were reported as the cycle threshold value for both upstream of the envelope gene (E) and open reading (O) frame 1A.

The demographic for the patients are summarized in Table 1 . All 3 laboratory-confirmed MERS patients were on mechanical ventilators, with an average PaO2/FiO2 ratio of 196. The mean ICU length of stay and time from last positive tracheal aspirate for MERS-CoV RNA to environmental sampling were 9.3 days and 40 hours, respectively.

Sixteen surfaces were evaluated in each of the 3 ICU rooms, with 153 environmental samples processed ( Table 2) 

Our study revealed that MERS-CoV viral RNA was isolated from the environmental surfaces of MERS patients.

Currently, much remains uncertain about the transmission mechanism responsible for MERS nosocomial outbreaks. It was postulated from the outbreak in Al-Hasa, Saudi Arabia, in May-June 2012 that respiratory droplet and airborne transmission during aerosolgenerating procedures were the most likely transmission modes. 6 However, genetic data from a cluster in Hafr Al-Batin, Saudi Arabia, showed that direct person-to-person contact could not account for all of their cases, 7 therefore raising the likelihood of an alternate transmission mechanism. Studies on kinetics and patterns of viral excretion indicate that MERS-CoV RNA was isolated from urine and feces 13 and 16 days, respectively, after initial symptoms. 8 Viral shedding from respiratory aspirates may persist up to 33 days after illness onset. 9 Prolonged viral shedding 8, 9 and survival on surfaces for 48 hours 3 make it difficult to ignore contaminated environmental surfaces as a potential etiology of hospital outbreaks.

The rate of detecting MERS-CoV in our environmental samples was low (1.3%) compared with recently published data (PCR positive = 20.3%; culture positive = 4.0%), 4 but the current methods for isolating viruses from the environmental surfaces are not optimal. 5 Based on reported methodologies, we used a polyester swab, 1/4 lactated ringer solution, 5 PBS 5 and viral transport media 4 because they seem to give the best yield for isolating viruses from fomites. However, we did screening at the tail-end of our outbreak when the patients' viral load might have been low and our infection control practices might have been optimal. Additionally, MERS patients were managed in our ICU since 2013 and were usually cohorted in 1 unit where the staff became very meticulous about PPE use and environmental cleaning. Moreover, fairly weak disinfectants, such as povidone iodine, have a rapid virucidal activity (reduction in virus titer by ≥4 log10) against MERS-CoV, with an exposure time of just 15 seconds. 10 Further, Leclercq et al demonstrated that at relatively low temperatures of 56°C, only 25 minutes was needed to reduce the initial titer by 4 log10, while at 65°C virucidy dropped significantly to 1 minute. 11 This sensitivity to weak disinfectants could explain why our stringent environmental cleaning policies may have attenuated the recovery of viral genetic material on fomites within the patients' rooms.

Our finding of MERS-CoV RNA on environmental samples within our ICU shows that the viral material may contaminate fomites and can be a theoretical cause of nosocomial infections. However, we did not use viral cultures; therefore, we do not know if the positive PCRs correlate with live viruses or infectivity. Despite this, we believe that in addition to proper hand hygiene and correct PPE donning and doffing, meticulous environmental cleaning is of paramount importance to eliminate health care outbreaks.

Middle East respiratory syndrome coronavirus (MERS-CoV)

CDC's early response to a novel viral disease, middle east respiratory syndrome coronavirus (MERS-CoV)

Stability of Middle East respiratory syndrome coronavirus (MERS-CoV) under different environmental conditions

Environmental contamination and viral shedding in MERS patients during MERS-CoV outbreak in South Korea

Comparison of surface sampling methods for virus recovery from fomites

Hospital outbreak of Middle East respiratory syndrome coronavirus

Community case clusters of Middle East respiratory syndrome coronavirus in Hafr Al-Batin, Kingdom of Saudi Arabia: a descriptive genomic study

Clinical features and virological analysis of a case of Middle East respiratory syndrome coronavirus infection

Kinetics and pattern of viral excretion in biological specimens of two MERS-CoV cases

Rapid and effective virucidal activity of povidoneiodine products against middle east respiratory syndrome coronavirus (MERS-CoV) and modified vaccinia virus ankara (MVA)

Heat inactivation of the Middle East respiratory syndrome coronavirus