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Infection Risk

Phones move through care.
So do the microbes on them.

Mobile devices are among the most frequently handled objects in clinical workflows, yet studies repeatedly show they can carry clinically relevant bacteria.

The Financial Reality of Hospital-Acquired Infections

Hospital-Acquired Infections cost US hospitals up to $45 billion every year.

The organisms most responsible for those infections, MRSA, Staphylococcus aureus, Enterococcus, and Acinetobacter are the same organisms found on healthcare worker phones in study after study. Phones travel between every patient room, every shift, with no cleaning protocol designed to address them.

$45B
Annual HAI cost to US hospitals
Direct medical costs of hospital-acquired infections each year across the United States.
Anderson et al., PMC, peer-reviewed
1 in 31
Hospital patients have an HAI on any given day
CDC estimates approximately 722,000 HAIs occur in US acute care hospitals annually.
CDC, National and State HAI Progress Report
$28K+
Average cost of a single surgical site infection
Each surgical site infection adds an estimated $28,219 in direct costs per patient hospitalization.
AHRQ, Estimating Additional Hospital Inpatient Cost
75K
Deaths attributed to HAIs annually in the US
HAIs remain among the leading causes of preventable death in US healthcare facilities.
CDC, National Center for Emerging and Zoonotic Infectious Diseases
The Gap

The pathogens behind these numbers, MRSA, Staph aureus, Enterococcus, Acinetobacter, and Pseudomonas are consistently identified on healthcare worker smartphones. Phones are not a theoretical risk. They are a documented, unaddressed gap in every infection control protocol currently in use.

What Studies Have Found

The contamination rates are hard to ignore.

99.3%
of healthcare workers' smartphone screens found to be bacterially contaminated
Loyola et al. (2021), peer-reviewed hospital study of HCW smartphones
97.8%
contamination rate of healthcare workers' mobile phones in a separate study
Simmonds et al.; 9.5% MRSA-positive, 11.2% ESBL E. coli-positive among sampled devices
40–60%
contamination rates reported across studies in published literature reviews
Pooled findings across multiple systematic reviews of HCW mobile device contamination
The Transmission Picture

A phone does not stay in one place.

A healthcare worker's phone travels with them. It goes into a patient room, onto a nursing station, into a break room, and back again. Along the way it is picked up, set down, spoken into, and handed off. Unlike hands, it is rarely cleaned between those moments.

WHO hand-hygiene guidance explicitly treats objects in a patient's immediate surroundings as contamination-relevant touchpoints. CDC guidance on environmental cleaning highlights high-touch surfaces in healthcare settings as a specific concern. The phone sits squarely in both categories, yet it falls outside most cleaning protocols.

Organisms Identified on Healthcare Worker Phones
MRSAA type of Staphylococcus aureus that can be harder to treat and is associated with skin, wound, and bloodstream infections. Staphylococcus aureusCommonly found on skin and surfaces and can spread between users through shared contact points. EnterococcusCan spread through shared contact surfaces and is associated with urinary tract, wound, and bloodstream infections. AcinetobacterAble to persist on surfaces and associated with pneumonia, wound, and bloodstream infections in hospitalized patients. PseudomonasKnown to persist on surfaces and equipment, particularly in environments with frequent handling. ESBL E. coliA resistant form of E. coli associated with urinary tract and bloodstream infections and spread through contact with contaminated hands or surfaces. ColiformsSpread through contact with contaminated hands and often found on frequently touched surfaces.

Organism identification sourced from published reviews and studies on healthcare worker mobile phone contamination.

Escherichia coli Staphylococcus Aureus Bacillus Cereus Clostridium Perfringens Pseudomonas Aeruginosa Fecal Bacteria (Streptococci)

Illustrative representation. Organisms identified in published studies on HCW mobile phone contamination.

Observed Impact in Clinical Settings

Shared desk phones carry a contamination burden that's easy to overlook.

Shared desk phones in hospital environments are handled repeatedly across shifts and users with little consistency in cleaning between contacts. The WHO reports that office phones carry an average of 25,127 bacteria per square inch, and standard surface cleaning cannot reach microbes living deep inside the handset holes.

In a controlled hospital-based study, disposable barrier covers were evaluated on shared desk phones over a 48-hour period. The difference between protected and unprotected devices was substantial.

The reduction was statistically significant (Chi-square, p <0.05), supporting the role of continuous barrier-based protection in limiting microbial contamination on shared communication devices.

Dominant organisms identified included gram-positive bacteria such as Staphylococcus species, common healthcare-associated pathogens.

Source: Cadenas Cedeño O. Effectiveness of a Protective Barrier Cover Against Microorganisms in Units Used in Hospital Environments. HULA-IA and IVSS, Mérida, Venezuela. Office for the Integral Attention of the Biomedical Scientific Researcher (OIA-BSR), 2021.

80%
Unprotected Phones
of unprotected shared desk phones exceeded 100,000 CFU, the threshold for clinically significant bacterial contamination (n=24)
25%
Protected Phones
of phones using a disposable barrier cover showed the same growth, a statistically significant reduction (Chi-square, p <0.05, n=24)
↓
55-percentage-point reduction in bacterial growth on shared desk phones with barrier protection vs. unprotected devices
Current Approaches Fall Short

Existing methods have meaningful limitations.

Infection control protocols have evolved considerably, yet mobile devices remain a persistent gap. Here is how current approaches compare to a continuous barrier cover.

Disinfecting Wipes
Requires dwell time that rarely happens
EPA-registered wipes need 30 seconds to 4 minutes of wet contact time. In practice, staff wipe for a few seconds and move on. Protection disappears with the next touch.
Sterra Cover
No technique required
A cover works the same regardless of who is using the phone or how rushed the shift is. There is no dwell time, no technique, and nothing to audit.
UV Sanitizers
Point-in-time only
Phones leave the sanitizer and immediately re-enter the clinical environment. Contamination begins again with the first touch. Impractical during active care.
Sterra Cover
Continuous protection throughout use
The cover stays in place for the entire duration of use. Even if a phone is already contaminated, staff handle the cover rather than the phone surface. When it is removed, the contamination leaves with it.
Cleaning Policies
Impossible to enforce consistently
Adherence varies by shift, unit, and workload. Most policies do not specifically address personal devices. There is no reliable way to know if a phone was cleaned before this encounter.
Sterra Cover
Visible compliance at every encounter
The cover is either on or it is not. Staff, supervisors, and patients can all see it. No reporting, no auditing, no guesswork about whether the phone was cleaned before this shift.

A cover does not require perfect compliance. It just has to be on.

The Evidence Base

Three things the research consistently shows.

01

Phones are high-touch objects in care settings

WHO hand-hygiene guidance treats objects in a patient's immediate environment as contamination-relevant. CDC guidance on environmental cleaning flags high-touch surfaces as a priority. Phones belong in both categories.

WHO Hand Hygiene Guidelines; CDC Environmental Cleaning Guidance
02

Healthcare worker phones are often contaminated

One hospital study found 99.3% of smartphone screens contaminated. Another found 97.8%, including 9.5% MRSA. Across literature reviews, contamination rates in the 40 to 60 percent range are commonly reported.

Loyola et al. (2021); Simmonds et al.
03

The problem is cross-transmission, not just contamination

Phones travel between patients, rooms, and staff. The organisms found on them, including MRSA, Enterococcus, and Acinetobacter, are clinically relevant. That turns a dirty screen into a potential transmission pathway.

Systematic reviews; Ulger et al.; Goldblatt et al.
How Sterra Helps

A passive barrier, built into how work already happens.

Sterra makes Disposable Covers for Deskphones and personal smartphones. Each cover creates a clean barrier between the device and the user, without adding steps to an already demanding shift.

The goal is not to replace existing cleaning protocols. It is to close a specific gap those protocols were not designed to address: the phone that moves room to room, hand to hand, without anyone stopping to wipe it down.

Full device functionality
Touchscreen, Face ID, camera, and all controls remain fully accessible through the clear windows. Nothing about how staff use their devices changes.
Designed for infection control teams
Built to support existing IPC frameworks, not complicate them. Simple to document, simple to audit, and straightforward to roll out across a unit or facility.
Works across care settings
ICU, ED, med-surg, long-term care, outpatient. Anywhere shared phones are part of the workflow, Sterra fits without changing how the unit operates.

See what Sterra does about it.

The evidence points to a consistent gap. Sterra makes a product designed to close it without adding steps to your team's workflow.

See the Product

Supporting Evidence

Review the sources and supporting evidence behind Sterra’s infection-risk framing.

View Supporting Evidence
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