Microbes recovered from hands can be divided into two categories: transient and resident organisms. Transient microorganisms tend to colonize the superficial layers of skin and while they are amenable to removal by washing hands with plain (i.e., non-antimicrobial) soap and water, they are responsible for most HAIs. Resident organisms are attached to deeper layers of the skin and while they are more resistant to removal, they are less likely to be associated with HAIs.
Hand surfaces harbor >150 unique bacterial phylotypes and as many as 4742 transient phylotypes have been identified. The number of resident and transient organisms on the hands of HCP vary greatly, yet it is often relatively constant for any one individual.1 It is also of note that the hands of HCP may become persistently colonized with transient pathogenic organisms (e.g., *S. aureus*, gram-negative bacilli, or yeast). HCP may acquire transient microorganisms during:
contact with a patient’s intact skin (e.g., when taking a pulse or blood pressure),
contact with nonintact skin and mucous membranes,
direct contact with blood and other potentially infectious material (OPIM); and
contact with contaminated instruments, equipment, and environmental surfaces.
The transmission of healthcare-associated pathogens from one patient to another via the hands of HCP must meet 4 criteria:2,3
Organisms present on the patient’s skin or mucous membranes, or on contaminated instruments, equipment, and environmental surfaces must be transferred to the hands of HCP.
The organisms transferred must then be capable to survive for at least several minutes on the hands of HCP.
Hand hygiene by HCP must be inadequate or omitted entirely, or the agent used for hand hygiene is inappropriate.
The contaminated hands of HCP must come in direct contact with another patient, or with an inanimate object that will come into direct contact with the patient.
Standard Precautions mandate that HCP wear gloves.2-4 However, simply wearing gloves does not provide complete protection against cross-infection. Bacterial flora colonizing patients have been recovered from the hands of ≥30% of HCP who wore gloves during patient contact.5-9 Since pathogens can be transmitted via small defects in gloves or by contamination of the hands during glove removal, wearing gloves does not eliminate the need for appropriate hand hygiene practices.9-10
Excerpts published by the CDC in 2016 from the Guidelines for Infection Control in Dental Health-Care Settings – 2003 emphasize that oral HCP must perform hand hygiene with either a non-antimicrobial or an antimicrobial soap and water when hands are visibly soiled; otherwise, the preferred method of hand hygiene in clinical situations is with an alcohol-based handrub; and when performing surgical procedures oral HCP must perform surgical hand antisepsis.3