Food service: An overlooked potential vector for hospital infection

To the Editor—In more than 25 years of working with hospitals to eliminate pests, I have observed an increasingly superficial approach to reducing the sources of sustenance for insects ¹ and rodents ² that can serve as vectors for disease-causing organisms. Conditions have degenerated from the time when hospitals had dedicated food service professionals as employees. Now this work commonly is done by contractors without the same knowledge, commitment, ³ or hospital-specific training.

Hospitals largely rely on topical agents for cleaning that address the surface contaminants but not the residual contamination. Instead of eliminating the hidden food-decaying organisms that attracts flies, hospitals now use electrocution devices that introduce and disseminate exploded insect bodies into HVAC systems, further contaminating surgical theatres, ICUs, and patient rooms. Figure 1 provides examples of the many potentially disease-transmitting conditions I have observed.

Fig. 1. Patient floor stationed food tray cart: satellite fly proliferation site.

Certain species of filth flies can travel for miles within a 24-hour period searching an entire facility for decaying organic matter for additional propagation. ⁴ Adult fruit, drain, or moth flies are prolific breeders, resulting in a wide area of invasion far from the original breeding sites. Therefore, all occurrences of degenerating organic debris can be original or satellite breeding opportunities.

Filth flies are capable of breeding in more types of materials than any other structure-infesting fly. In buildings, they be may found breeding in drains, trash containers, dumpsters, rotting produce, recycle bins, grease traps, garbage disposals, crawl spaces, and any site where moist organic matter can accumulate for a few days or longer. Fly larvae have been found in the open wounds of patients, and even in the mouths of intubated patients (I have personally seen this).

Food service areas present the number-one opportunity to prevent disease. Food contaminates! It attracts insects and other pests. We need to understand this potential for contamination when storing and preparing food and utensils. Hospital buildings are like our own human bodies. The very systems that support our lives also are vulnerabilities for infection. Bricks and mortar can protect the hospital like the integument protects the body. Heating ventilation and air conditioning (HVAC) systems can exclude or admit pathogens in the same way as the human respiratory system. Food-waste management systems can prevent or allow viruses or bacteria, just like the digestive system.

Pests are attracted to buildings in the same way that disease-causing pests are attracted to humans. We invite them in with smells and opportunity. We give them a home in decaying matter. We use a symptom-based approach instead of a thorough evaluation and investigation. When we do not appreciate and address these attractions, we end up with pests of all sorts and increased potential for disease.

Pesticide use is regulated and cannot be a substitution for sanitation and maintenance. In situations where organic debris are degenerating, topical pesticide applications degenerate much faster than their intended label application parameters, and anti-pest baits are mitigated by food competition.

A 3-word definition of food sanitation is protection from contamination. With this in mind, all hospital functions and operations must be included in a sanitation program. All food products must be protected from contamination from the receiving dock (and before), right through distribution and removal. Sanitation is a dynamic and ongoing function and cannot be sporadic. When embedded in a healthcare facility with a special functions (eg, surgical theatre, pharmacy, dialyses care unit, etc), it becomes even more critical. Adequate cleaning and maintenance are crucial first steps in environmentally compatible fly control and will provide long-term discouragement of additional pest invaders.

I recommend the following systematic approach: (1) prioritized leadership and hospital administrative commitment to sanitation; (2) empowering and educating food service workers in illness prevention; (3) emphasizing environmentally compatible sanitation methods coupled with strategic and specific applications of anti-pest agents when required; and (4) looking beyond surface cleanliness to follow food as an attractor of pests.