Determining the Infectious Dose of Influenza Aerosols in a Mouse Model
SAINT JOSEPH COLL WEST HARTFORD CT
Pagination or Media Count:
An animal model system was developed for measuring the infectivity of aerosol challenges delivered to mice via a nose-only bioaerosol device. The measured dimensions of the first organism evaluated, Francisella tularensis LVS, was found in initial experiments to be considerably larger than its reported proportions, which eliminated it as a candidate for animal aerosol filtration and respiratory exposure studies. Influenza APR834 H1N1 was selected as a replacement and its aerosol characteristics were found to be satisfactory for filtration studies. After a direct inoculation experiment demonstrated susceptibility to three strains of mice, the Controlled Aerosol Test System was used to deliver a series of graduated doses of this virus by inhalation to groups of five 25-g female CD-1 mice, from which a median infective dose MID50 of less than 40 TCID50 was inferred from weight loss, and a lower-limit value of 12 TCID50 was calculated from cytopathic effect and qRT-PCR data. The method demonstrated in this study can be used to further the development of rodent models for evaluating aerosol delivery of pharmaceuticals and technologies for infectious disease control, and to create and validate computational models for aerosol delivery. In addition, the original work of evaluating the efficiency of respiratory protection equipment from infective particles of penetrating particle sizes can now be completed.
- Medicine and Medical Research