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Pseudomonas aeruginosa infections
P. aeruginosa, a species of strictly aerobic Gram-negative rods found widely in the environment, is an opportunistic pathogen of man and animals. It causes ear and eye infections of humans and pet dogs. In people with large burns it can cause serious, general, sometimes fatal infections, as well as causing destruction of skin grafts. It also infects leg ulcers, surgical wounds and prostheses and the urinary tract. The respiratory tract can be infected especially in ventilated patients and bronchiectasis and cystic fibrosis (CF) patients, in whom mucoid variants of P. aeruginosa are common; they produce much of a slimy substance, alginate. P. aeruginosa is resistant to most of the commonly used antibiotics and readily acquires new resistance. Antibiotics which are active against a strain in the laboratory, frequently fail to eliminate the strain from an infected patient's respiratory tract. One reason for this may be the development of attached populations, microcolonies, in the respiratory tract which resemble biofilms that have been shown to be much less sensitive to antibiotics [1], than are planktonic (free floating) bacteria of the same strain. Recently resistance in Gram-negative bacteria, including P. aeruginosa has increased greatly. Genetic determinants encoding resistance to all β-lactam antibiotics which can be transmitted between different genera of bacteria, the transmissible carbapenemase determinants, are becoming very common in some countries, are found in P. aeruginosa , worryingly including some strains that are carried chronically by CF patients. Strains sensitive only to colistin, which is nephrotoxic and of limited efficacy, are becoming increasingly common. Hence, other treatments are needed.
Early general phage therapy work
In 1915 Twort [2], reported his discovery of filter-passing, replicating agents affecting Micrococcus spp and 'Typhoid-coli'bacilli and suggested that vaccines be prepared with them. d'Herelle in 1917 reported similar findings in Shigella and 'paratyphoid A bacilli'[3]. He also found that at the time of clinical improvement of dysentery patients bacteriophage (a name he coined) appeared, and he made the first report of phage prophylaxis; cultures of the 'anti-microbe'were able to 'immunize'rabbits against infection by 'Shiga bacilli'. There followed a period of investigation into phage therapy, and phages were marketed for a range of conditions, some of which were not even infections. Some early experimental animal work did yield positive...