Biofilm can be defined as microbial cells adherent to a living or non-living surface, which are embedded within a self-produced matrix of extra-cellular polymeric substances (EPS). Biofilm provides tolerance to antimicrobial agents and can result in persistent inflammation and infection. [1,2]
Biofilm is a huge problem:
- It’s present in at least 78 % of chronic wounds .
- It’s difficult to eradicate.
- It delays wound healing [4,5].
Biofilm operates in a wound in three different modes:
1. DEFENCE MODE
EPS shields micro-organisms from antibiotics, antiseptics and the host’s immune response. This biofilm-specific defence and the inability to breach the EPS matrix contributes to a chronic inflammatory state in the wound environment. 1
2. RECOVERY MODE
Biofilm is difficult to remove completely as it is attached to the wound bed. Biofilm can reform in as little as 24h, even following aggressive debridement . To prevent biofilm reformation, effective long-lasting antimicrobial protection is needed .
3. ATTACK MODE
Biofilm can spread and form new colonies by constantly releasing micro-organisms from the mature biofilm structure . This can increase the risk of cross-infection both within the wound and in the surrounding environment.
 Gurjala AN et al. Development of a novel, highly quantitative in-vivo model for the study of biofilm-impaired cutaneous wound healing. Wound Rep Reg (2011) 19 400–410.
 Hall-Stoodley LI et al. Towards diagnostic guidelines for biofilm-associated infections. FEMS Immunol Med Microbiol. 2012; 65:127–145.
 Malone M et al. 2017. The prevalence of biofilm in chronic wounds: a systematic review and meta-analysis of published data. JWC; 20–25.
 Hurlow, J., Couch, K., Laforet, K., Bolton, L., Metcalf, D. et al. (2015). Clinical Biofilms: A Challenging Frontier in Wound Care. Advances in Wound Care, 4(5). 295–301.
 Metcalf, Bowler. Biofilm delays would healing: a review of the evidence. Burns Trauma 2013; 1: 5–12.
 Wolcott RD et al. Biofilm maturity studies indicate sharp debridement opens a time dependent therapeutic window. J Wound Care. 2010; 19: 320–328.
 Costerton JW, Stewart PS, Greenberg EP. Bacterial Biofilms: A Common Cause of Persistent Infections. 1999: 284 Science.