Longitudinal prevalence and co-carriage of pathogens associated with nursing home acquired pneumonia in three long-term care facilities.

Nursing home acquired pneumonia (NHAP), and its subset - aspiration-associated pneumonia, is a leading cause of morbidity and mortality among residents in long-term care facilities (LTCFs). Understanding colonization dynamics of respiratory pathogens in LTCF residents is essential for effective infection control. This study examines the longitudinal trends in prevalence, persistence, bacterial load, and co-colonization patterns of five respiratory pathogens in three LTCFs in Phoenix, Arizona. Anterior nares and oral swabs were collected every other week and tested using qPCR for , , , , and . Weekly average positivity rates were 17.75% for (0% - 39.39%), 9.95% for (0% - 37.74%), 31.89% for (1.79% - 41.67%), and for 28.00% for (0% - 55.36%). was not detected. and predominantly colonized the oral cavity, while and predominantly colonized the nasal cavity. and colonizations were significantly more persistent than and , with persistence correlating with significantly higher bacterial loads. Co-colonization did occur in ~20% of positive samples, but appeared to be due to random chance. This study reveals distinct colonization patterns among respiratory pathogens in LTCF residents, highlighting differences in site-specific prevalence, persistence, and bacterial load. These findings underscore the importance of longitudinal monitoring to inform targeted infection control strategies in LTCFs.