Rhinovirus contamination of surfaces in homes of adults with natural colds: transfer of virus to fingertips during normal daily activities

Abstract

Multiple surfaces contaminated with rhinovirus were detected in hotel rooms by reverse transcriptase-polymerase chain reaction (RT-PCR) following occupancy by a cold sufferer. Whether infectious rhinovirus contaminates surfaces in homes and is transferred from surfaces to fingertips through normal activities is not known. Nasal secretions from 30 subjects with new colds were tested for rhinovirus genome by RT-PCR; infectious rhinovirus was sought with tissue cultures. Each subject identified 10 sites in their home touched during the preceding 24 hr. Samples from sites were tested for rhinovirus by RT-PCR and cell culture. Later, each subject's mucus (stored at -70°C) was deposited on surfaces for testing transfer to fingertips through daily life activities such as flipping a light switch, touching the telephone keypad, and holding the telephone handset. Nasal secretions from 16/30 subjects were positive for rhinovirus by RT-PCR; 66 (41%) of 160 surfaces in homes were positive. Contaminated surfaces included doorknobs (6 positive/18 tested), refrigerator door handles (8/14), TV remote controls (5/10), and bathroom faucets (8/10). Five (19%) of 26 RT-PCR positive sites from culture positive subjects were positive in cell culture. Nasal mucus from six culture positive subjects was deposited on objects. Infectious rhinovirus was detected on 22% of fingertips following contact with objects contaminated for 1 hr; transfer dropped to 3% after 24 hr of contamination, and 0% after 48 hr. Infectious rhinovirus found on surfaces in homes of people with colds can be transferred to fingertips, but infectivity of virus in mucus declines by 24 hr after deposition.