The use of bacteriophages to treat bacterial infections (phage therapy) is considered a possible solution to the antimicrobial resistance crisis. However, phage therapy is not a new concept. The discovery of phages in the early twentieth century was closely tied to clinical practice, and phage therapy quickly spread around the world.The use of phage therapy in twentieth century South America is still shrouded in mystery and has been mentioned only briefly in recent scientific literature. Research on Brazilian reference collections of medical texts revealed that Brazil was an important, but so far little-known, player of phage therapy, uncovers interesting priority claims and missing pieces of phage therapy history. Of note, there is the widespread use of phages against bacillary dysentery and staphylococcal infections, with Dr José da Costa Cruz from the Institute Oswaldo Cruz as Brazil's leading expert and pioneer. This review about historical phage use in a South American country fills gaps in our knowledge about the "golden years" of phage therapy, providing information about successful experiences that can be useful against dangerous pathogens in our time.
Key points• Brazil had an important role in the golden years of phage therapy, which lasted until the mid-twentieth century.• Dr José da Costa Cruz from the Institute Oswaldo Cruz in Rio de Janeiro was the leading expert.• The first phage therapy cases in Brazil took place in 1921 during an outbreak of dysentery in Barbacena.• The mass testing of the Institute Oswaldo Cruz phage product during the Paulista revolution of 1924 preceded Dr d'Herelle's tests in India and the Soviet Union's tests on military troops.• Successful phage use in Brazil was against bacillary dysentery and staphylococcal infections.• The available information about phage therapy clinical cases and phage products was retrieved from the literature investigated and presented in this publication.
Research in contextEvidence before this study Reports summarising the use of phage therapy in Brazil were scarce before this review. Only three recent publications mentions, briefly and without details, that Brazilian doctors were involved with phage therapy in the 1920s. Sixteen sources of Brazilian medical publications were checked for phage-related information, looking at the period from 1915 (when Dr Frederik Twort published his phage discovery) to 1952. Any phage or phage therapy related words in titles and abstracts were used as inclusion criteria. The risk of bias associated with data inclusion is minimal, because the objective was to have all published material concerning phages.However, since routine phage therapy cases were not always published, the data presented here are probably only a fraction of the actual phage use at the time.