We're currently looking at utilizing a bioluminescent bacterial strains (i.e., Staphylococcus aureus and Pseudomonas aeruginosa) that can be detected in-vivo, in real-time using a luminescent imaging system (Ilumina II, Perkin Elmer) to follow the development of osteomyelitis and wound infections in small animal models. This new technology can help minimize the number of animals tested and allow the infection to be followed in individual animals throughout the whole process from start to finish, enabling for a more 'individualized' approach to potential treatments.
Bacterial contamination of an open wound can impede the wound-healing process and result in infection. Factors that affect the progression of infection include the bacterial count, the virulence of the organism(s), and the host immune response. Since their discovery in the 1940’s, antibiotics have been used to fight against bacterial infections; however, the misuse and overuse of antibiotics has resulted in the evolution of antibiotic resistant bacterial infections that are difficult to treat.
Despite current infection intervention strategies implemented to treat combat-related injuries, one-third of such injuries are complicated by infections. Wound infections are influenced by a number of factors including wound type and severity, contamination from foreign material, timing of initiation of antimicrobial treatment, delay in medical care, adequacy of wound debridement, definitive surgical care, and the presence of opportunistic pathogens at the treatment facilities. Staphylococcus aureus, P. aeruginosa and Klebsiella pneumoniae, known to have a high prevalence of multi-drug resistance, have been isolated from many battlefield injuries. Infections acquired during active duty or while being treated at Department of Defense facilities or various healthcare facilities have been found to persist after patients enter a Veterans Health Administration (VHA) facility. There has been an increase in the complexity of infectious disease management reported on Veterans who suffered from combat wounds obtained during the Gulf War era (i.e. anyone who served on active duty from August 2, 1990 to present). Within the next 10 years, the Veteran population from the Gulf War era is projected to peak at almost 9 million Veterans.
Approximately one-third of Veterans admitted to VA acute care medical facilities have both multidrug resistant P. aeruginosa and methicillin-resistant S. aureus (MRSA). Patients colonized with these opportunistic pathogens can bring the organism into hospitals and long-term care facilities where they can spread and infect susceptible patients. Patients suffering from infections by these multi-drug resistant organisms (MDRO’s) result in higher treatment costs, longer hospital stays, and higher rates of mortality compared to patients with susceptible bacterial infections.