9. Conclusion and future directions
This review represents the first time pan-pathogen antimicrobials have
been formally identified and characterised, and the first time such
drugs have been associated with ‘magic blanket’ antimicrobial
development. Azithromycin, ivermectin, niclosamide, and nitazoxanide
assert a unique advantage over traditional antibiotics and antivirals in
their ability to treat a wider range of infectious diseases by
regulating the host-pathogen interactome. Like with immunomodulatory
drugs, however, the use of biomarkers will inform the appropriate
application and dosage stipulations of these drugs across infection
types. Tempered by their contribution to antimicrobial resistance, such
broad-acting drugs may constitute an ‘emergency treatment class’ for
global health emergencies such as COVID-19, future respiratory
pandemics, and potential bioterrorist attacks; a property reinforced by
their extensive repositioning for pulmonary disorders and substantial
affordability and international availability relative to antibody,
vaccine, and plasma-based strategies. Ultimately, formal recognition of
pan-pathogen antimicrobials can facilitate discovery of conserved
infective and anti-infective mechanisms and pharmacophores, enabling the
long-campaigned unification of the disparate fields of bacteriology,
fungology, parasitology, and virology, while heralding a paradigm of
antimicrobial development conceptually distinct from the antibiotic era
of the 20th century.