Smartphones and the Invisible Microbial Exchange with Human Skin
Introduction
The human microbiome consists of trillions of microorganisms found in various body areas such as the skin and gut. The skin microbiome plays a vital role in barrier protection, immune modulation, and resistance to pathogens.
Due to the frequent touching of objects, environments, and faces, hands experience significant microbial flux and variability. Smartphones, which are touched hundreds of times each day, have become important vectors in this process, exhibiting a 20-25% bacterial overlap with the hands of their owners according to high-throughput sequencing. This two-way transfer could potentially lead to systemic effects through the skin-gut axis.
Studies indicate that personal smartphones or mobile phones host microbial communities similar to those found on the user's skin. Many of the prevalent bacterial species on a person's smartphone are also typically present on their hands, suggesting ongoing microbial transfer between the skin and frequently handled personal devices. Thus, smartphones could be regarded as extensions of the human microbiome, carrying unique microbial signatures of individuals.
As these devices are touched numerous times throughout the day, they may promote microbial transfer across various body areas through contact with the face and other exposed regions. This continuous exchange might alter temporary microbial exposure patterns and affect the interactions between the skin and other microbial environments in the body.
Role of Hand Microbiome
The skin is home to various microbes, and a few of the prominent ones are Propionibacterium, Staphylococcus and Corynebacterium. These microorganisms produce antimicrobials, compete against pathogens, and help train the immune system, which together aid in preventing infections.
The composition of the hand microbes exhibits variability among individuals due to factors like hygiene, gender, and handedness. The hand microbiome serves as the main source for transferring a variety of skin bacteria, such as Cutibacterium and Staphylococcus, onto smartphones with each touch. If hand hygiene is not maintained, then there is a chance of harmful microbes being transferred to the surfaces of the smartphones. Therefore, it is important to maintain good hand hygiene practices to avoid contamination of smartphones.
Smartphones as Reservoirs
Mobile devices gather a variety of microbes from skin, saliva, feces, and the environment, with heat and humidity promoting the survival of opportunistic bacteria such as Pseudomonas and Enterococcus.
Research indicates that each phone has a unique microbial signature, with the bacteria from the owner's hands predominating on phone swabs, in contrast to what is found on public surfaces.
The smartphone generates heat, and the display of the smartphone captures oils and sweat, which together create a favorable environment for the growth of microbes. The enclosed nature of pockets enhances the longevity of these microbes, preventing die-off and forming a unique microbial fingerprint. This initiates a contamination cycle where clean hands are reinoculated by unclean smartphones, allowing pathogens to persist for days.
Disrupting this cycle by cleaning the phone diminishes the hand microbiome's predominant role in the microbial ecology of the device.
Smartphones as Microbial Transmitters
Microbial Risks in Healthcare Workers
Smartphones utilized by healthcare workers often harbor enteric bacteria like Escherichia coli, Klebsiella spp., and Pseudomonas spp., which are typically linked to gastrointestinal infections from patient contact, environments, or restrooms, persisting long on device surfaces. Repeatedly handling these contaminated devices can promote the transfer of microbes to the hands, even after following standard hand hygiene protocols. Subsequently, eating with the contaminated hands after using the phones or unconsciously touching the face can lead to the ingestion of these microorganisms into the gastrointestinal system.
Frequent exposure to opportunistic pathogens may lead to temporary changes in gut microbial makeup. Long-term colonization by these microorganisms has been associated with gastrointestinal issues and a heightened risk of infection.
Although smartphones do not directly lead to illness, they serve as carriers in environments with frequent contact, gradually upsetting gut equilibrium; regular cleaning interrupts this cycle of exposure.
Health Effects of Smartphone Use in the Toilet
Using smartphones while in the toilet can lead to unexpected physiological effects. Studies show that excessive smartphone use while in the toilet may correlate with a higher risk of hemorrhoids, postural strain, irregular bowel movement patterns, and overall physical discomfort.
In a study it was observed that the surface of smartphones used in the washrooms were contaminated with fecal bacteria. This suggests that such practices can lead to higher risk of infections transmitted via the fecal-oral route.
Hygiene Balance Strategies
Wash hands with handwash pre-meals and before touching your face.
Wipe phones weekly with 70% ethanol
Ban the usage of phone in washrooms/toilets
- Catherine Praveena J
Also Read: How to Protect Your Skin and Microbiome from Pollution
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