# Pattern of Bacterial Flora and Effect of Disinfection on Fingerprinting Biometric Devices at a Tertiary Care Health Facility: An Interventional Study

## TL;DR

This study found bacteria on fingerprint devices in a hospital and showed that regular disinfection with alcohol reduces microbial transmission risks.

## Contribution

The study demonstrates the effectiveness of isopropyl alcohol disinfection in reducing bacterial load on fingerprint devices in healthcare settings.

## Key findings

- Bacterial growth was observed on 38% of clinical and 20% of non-clinical biometric devices at baseline.
- Disinfection with 70% isopropyl alcohol reduced bacterial growth by 83% after 24 hours.
- Bacterial load increased again by 82% after seven days, highlighting the need for regular disinfection.

## Abstract

Introduction

Recently, many public and private sector institutions and hospitals have installed biometric fingerprint devices for attendance purposes. This step is taking us toward modernization but biometric devices have their cons and pros; if not sterilized at regular intervals, then it may be a potent cause of transmission of various infections. Many studies have reported the presence of coagulase-negative Staphylococcus aureus (CONS), methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, Pseudomonas, and others.

Aim

To study the pattern of bacterial flora and the effect of disinfection on fingerprinting biometric devices at a tertiary care health facility.

Materials and methods

A total of 138 biometric devices were used, out of which 105 were frequently (at least 50 uses per day) used and functional. So, 105 samples were collected on day zero (baseline), of which 43 and 62 were from clinical and non-clinical groups, respectively. The devices were disinfected with isopropyl alcohol (w/v 70%) and subsequent samples were taken on day 1 (after 24 hours) and day 7. The samples were collected and transported to the microbiology lab for culture and incubation.

Statistical analysis was performed using SPSS software version 25 (IBM Corp., Armonk, NY) employing chi-square, Cochran’s Q test, and post hoc test. A p-value ≤0.05 at a 95% confidence interval was considered to be statistically significant.

Results

At baseline (day 0), bacterial growth was observed in 13 (38%) devices from the clinical group and 10 (20%) from the non-clinical group. After disinfection with 70% isopropyl alcohol, bacterial growth was reduced by 83% on day 1 but increased by 82% on day 7. These changes were statistically significant (p ≤ 0.05).

Conclusion

The present study concluded the definite presence of bacterial flora on the biometric fingerprint devices which are prone to carry and transmit microorganisms indirectly from person to person. The surface of biometric fingerprinting devices should be disinfected daily. If not possible, it should be done on an average of every third day to control and minimize the transmission of microorganisms.