Understanding Biofilm: How to Manage It for Animal Wounds

Biofilm is one of the most important concepts to understand when managing wounds at risk for New World Screwworm infestations.

What is Biofilm?

A biofilm is a slimy, protective layer created by bacteria that attaches to wounds and damaged tissue. Inside this layer, bacteria are protected from:

• Antibiotics
• Disinfectants
• The animal’s immune system
• Normal wound healing processes

Think of biofilm as a bacterial "fortress" covering the wound.

Why Biofilm Matters with New World Screwworm

1. Screwworms Are Attracted to Wounds

   Adult screwworm flies seek out open wounds, surgical sites, branding/castration wounds, tick bites and umbilical areas in newborns. Biofilm-producing bacteria increase Tissue damage, Moisture, Odor, and Wound exudate. These factors make wounds more attractive to egg-laying flies.

2. Biofilm Delays Healing

   A wound covered in biofilm remains inflamed, wet, infected, and is slow to close. The longer a wound remains open, the longer it is vulnerable to screwworm attack.

3. Larvae and Bacteria Work Together

   Screwworm larvae damages healthy tissue, creates larger wounds, and increases fluid discharge. This allows more bacterial growth and biofilm formation, creating a vicious cycle: Wound → Biofilm → Delayed Healing → Fly Attraction → Screwworm Infestation → Larger Wound → More Biofilm

4. Hidden Infections Can Remain After Larvae Removal -

   Even after removing larvae and treating with an insecticide, Biofilm may still be present, bacteria may remain protected and healing can stall. Without addressing the biofilm, wounds may continue to deteriorate.

Biofilm Control Strategies for Screwworm Preparedness

• Clean and Debride - Remove the dead tissue, dirt, exudate, and maggots. Mechanical removal is the most effective way to disrupt biofilm.
• Flush Thoroughly - Use products such as P2 Probiotic Spray, Saline, Chlorhexidine solutions (when appropriate), and Veterinarian-recommended wound cleansers.
• Promote Rapid Healing - The goal is to close wounds quickly. Ultimately, keep wounds clean to control flies, monitor them daily, and treat infections promptly.
• Fly control is Essential - Use effective fly control products like fly tags, fly sprays, premise control, and wound protectants. Reducing fly pressure pulls down the chances of screwworm egg deposition.

The Key Message for Producers

A screwworm fly needs an open wound. Biofilm keeps wounds open.

This is why biofilm management should be part of every New World Screwworm (NWS) preparedness program alongside daily wound inspections, immediate wound treatment, aggressive fly control, and veterinary intervention when infestations are suspected.

This is also an excellent educational point for livestock producers because biofilm is often overlooked, yet it directly affects wound healing and susceptibility to screwworm infestations.

Products that can help:

• P2 Probiotic Power Pet-Heal Wound Treatment, 4 oz - This soil-based probiotics eliminates harmful bacteria by removing their food source - never killing the good bacteria your pet needs for healing.
• P2 Probiotic Power Pet-Heal Wound Cleaner, 4 oz - This wound cleaner eliminates harmful bacteria by removing their food source while strengthening beneficial bacteria. Gently cleans cuts, scrapes, surgical sites, hot spots, and more.

A probiotic approach may support wound health by reducing populations of odor-producing and pathogenic bacteria that contribute to chronic biofilms. Less odor and discharge can potentially make wounds less attractive to flies

For an active or suspected New World Screwworm infestation, probiotics are not a replacement for:

• Physical wound cleaning and debridement
• Larvae removal
• Approved insecticides or veterinary treatment
• Fly control measures
• Veterinary care

They would be considered a supportive tool within a broader wound-management program.

Healthy microbes help support healthy wounds.

By promoting a balanced microbial environment, P2 Probiotic Power may help reduce the buildup of harmful bacteria and biofilms that can delay healing, increase wound odor, and attract flies.

“Flies are attracted to wounds. Biofilms keep wounds open. Healthy microbes help create conditions that support healing.”