S evere acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has rapidly spread globally and, as of May 2, 2020, had caused >3 million confirmed coronavirus disease cases (1). Although SARS-CoV-2 transmission through respiratory droplets and direct contact is clear, the potential for transmission through contact with surfaces or objects contaminated with SARS-CoV-2 is poorly understood (2). The virus can be detected on various surfaces in the contaminated environment from symptomatic and paucisymptomatic patients (3,4). Moreover, we recently reported detection of SARS-CoV-2 RNA on environmental surfaces of a symptomatic patient's household (5). Because SARS-CoV-2 remains viable and infectious from hours to days on surfaces (6,7), contact with a contaminated surface potentially could be a medium for virus transmission. In addition, high viral load in throat swab specimens at symptom onset (8,9) and peak infectiousness at 0-2 days for presymptomatic patients (8) suggest that presymptomatic patients may easily contaminate the environment. However, data are limited on environmental contamination of SARS-CoV-2 by patients who may be presymptomatic. Therefore, to test this hypothesis, we examined the presence of SARS-CoV-2 RNA in collected environmental surface swab specimens from 2 rooms of a centralized quarantine hotel where 2 presymptomatic patients had stayed. The Study Two Chinese students studying overseas returned to China on March 19 (patient A) and March 20 (patient B), 2020 (Table 1). On the day of their arrival in China, neither had fever or clinical symptoms, and they were transferred to a hotel for a 14-day quarantine. They had normal body temperatures (patient A, 36.3°C; patient B, 36.5°C) and no symptoms when they checked into the hotel. During the quarantine period, local medical staff were to monitor their body temperature and symptoms each morning and afternoon. On the morning of the second day of quarantine, they had no fever (patient A, 36.2°C; patient B, 36.7°C) or symptoms. At the same time their temperatures were taken, throat swab samples were collected; both tested positive for SARS-CoV-2 RNA by real-time reverse transcription PCR (rRT-PCR). The students were transferred to a local hospital for treatment. At admission, they remained presymptomatic, but nasopharyngeal swab, sputum, and fecal samples were positive for SARS-CoV-2 RNA with high viral loads (Table 1). In patient A, fever (37.5°C) and cough developed on day 2 of hospitalization, but his chest computed tomography images showed no significant abnormality during hospitalization. In patient B, fever (37.9°C) and cough developed on day 6 of