Dear Editor,

Hospital-acquired infections (HAIs) cause morbidity, death, and economic burden in healthcare systems globally. The usual transmission routes of these HAIs include patient-to-patient transmission and contaminated surfaces or medical devices. Still, recent evidence suggests that insects are an underestimated but significant vector of superbugs in hospitals.1,2 The intricate organisation of patient rooms, surgery suites, and dining facilities in modern hospitals provides numerous opportunities for insects to act as vectors.3 Their mobility, biological traits, and frequent contact with polluted and clean environments make them ideal carriers of pathogens. 

Table 1 – Common vectors that spread superbugs within hospital environments.

Table 1 depicts the list of common vectors and superbugs they transmit within hospital environments. Superbug-carrying insects threaten hospital patients, especially those with impaired immune systems, open wounds, or invasive operations by extended hospital stays and death. Continuing insect pest infestations in healthcare settings could result in new infections after patients recover.4

Table 2 – Studies reporting the spread of HAI by insects

Table 2 illustrates a few case studies reiterating documented outbreaks of HAI due to insect activity.

Integrated Pest Management (IPM) strategies can be employed to prevent and control insects in hospital environments.5 IPM reduces hospital pest populations using multiple methods:

1. IPM programs use regular monitoring and inspections to spot insect infestations early.

2. Hospitals must adhere to strict sanitary regulations concerning waste disposal and food service. This involves regularly cleaning food preparation and serving areas, disposing of rubbish appropriately, and deep-cleaning insect-prone locations like storage rooms and laundry facilities.

3. Sealing cracks, maintaining window screens, and utilising automatic door-closing mechanisms can keep insects out of hospitals.

4. Insecticides can be an effective IPM strategy in non-patient regions.

The following challenges may be encountered in implementing the IPM strategies.

1. Addressing insects transporting superbugs is essential, but enhanced antibiotic stewardship programs are needed to restrict their spread. Antibiotics should only be provided when necessary and monitored to minimise abuse, which can promote drug resistance.6

2. Emerging technologies may help hospitals reduce insect populations. Existing pest management solutions can include UV light systems that kill insects or pheromone traps that keep pests away from patient care areas. Research is also investigating chemical-free pest control using biological controls like bacteria or fungi that target pest insects.7

3. Hospital insects and superbug transmission require further research. Hospital insect-vectored illnesses are an increasing hazard, and governments and public health organisations must adopt regulations to address ecological and medical concerns.

Superbugs transmitted by insects are an increasing menace to healthcare systems worldwide. Insects, often overlooked potential HAI sources, can carry and transmit MRSA, VRE, and resistant Gram-negative bacteria. These insects are potent infection carriers because they can move between polluted and sterile habitats. Integrated pest management, strict environmental cleanliness, and increased pest and disease surveillance can mitigate this threat. We must address antibiotic misuse in healthcare settings to reduce antibiotic-resistant microorganisms. Hospitals must identify insects’ role in superbug transmission and adopt prompt preventive actions.

CONFLICT OF INTERESTS STATEMENT

The authors declare no conflict of interest.

SOURCE OF FUNDING 

None

AUTHOR’S CONTRIBUTIONS

SG- Conceptualization; Data curation; Analysis; Writing the draft; Investigation; Methodology; Resources; Review & editing.

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