“The handshake represents a deeply established social custom. In recent years, however, there has been increasing recognition of the importance of hands as vectors for infection, leading to formal recommendations and policies regarding hand hygiene in hospitals and other health care facilities,”
Our results confirm that an occupied space is microbially distinct from an unoccupied one, and demonstrate for the first time that individuals release their own personalized microbial cloud.
Humans differ in their personal microbial cloud
Dispersal of microbes between humans and the built environment can occur through direct contact with surfaces or through airborne release; the latter mechanism remains poorly understood. Humans emit upwards of 106biological particles per hour, and have long been known to transmit pathogens to other individuals and to indoor surfaces. However it has not previously been demonstrated that humans emit a detectible microbial cloud into surrounding indoor air, nor whether such clouds are sufficiently differentiated to allow the identification of individual occupants. We used high-throughput sequencing of 16S rRNA genes to characterize the airborne bacterial contribution of a single person sitting in a sanitized custom experimental climate chamber. We compared that to air sampled in an adjacent, identical, unoccupied chamber, as well as to supply and exhaust air sources. Additionally, we assessed microbial communities in settled particles surrounding each occupant, to investigate the potential long-term fate of airborne microbial emissions. Most occupants could be clearly detected by their airborne bacterial emissions, as well as their contribution to settled particles, within 1.5–4 h. Bacterial clouds from the occupants were statistically distinct, allowing the identification of some individual occupants. Our results confirm that an occupied space is microbially distinct from an unoccupied one, and demonstrate for the first time that individuals release their own personalized microbial cloud.
Banning The Handshake From Health Care Settings: Doctors Say Social Custom Spreads Disease Regardless Of Handwashing
The Western social practice of handshaking has only grown more popular in recent decades with variations up high and down low now often accompanied by the ubiquitous “bro hug.” However, some doctors are pushing to “ban the handshake” in hospitals and doctor’s offices across the country to prevent the spread of communicable disease.
Physicians from the University of California, Los Angeles, argue in an editorial published Thursday in JAMA that handshaking thwarts the practice of handwashing to limit the spread of dangerous pathogens. Soon, health care workers and patients may see the following advisory: “Handshake-free zone: To protect your health and the health of those around you, please refrain from shaking hands while on the premises.”
Although research has long associated handwashing with decreases in bacterial colonization and hospital-acquired infections, only 40 percent of clinicians and other health care workers comply with such mandatory hygiene policies. Among patients and visitors, handwashing hygiene is even lower. And alcohol-based rubs, the most touted solution to hospital hygiene problems, remain ineffective against such dangerous pathogens as Clostridium difficile.