NASOPHARYNGEAL FLORA IN HEALTH AND DURING RESPIRATORY DISEASE IN ISOLATED COMMUNITIES IN ALABAMA AND LABRADOR

Area of Science:

• Microbiology
• Epidemiology
• Public Health

Background:

• Nasopharyngeal bacterial flora composition varies between healthy individuals and those with respiratory infections.
• Understanding microbial dynamics in isolated communities is crucial for public health interventions.

Purpose of the Study:

• To investigate the bacterial flora of the nasopharynx in isolated communities in Alabama and Labrador.
• To compare bacterial flora during normal periods versus periods of common cold and tracheitis epidemics.

Main Methods:

• Bacterial cultures were performed on nasopharyngeal samples from individuals in Alabama and Labrador.
• Flora was analyzed during periods of health and during outbreaks of common colds and tracheitis.
• Specific bacterial groups, including Gram-negative cocci, staphylococci, Pfeiffer bacilli, streptococci, and pneumococci, were quantified and characterized.

Main Results:

• Gram-negative cocci decreased during pathological states, while Pfeiffer bacilli and pneumococci increased during epidemics.
• Pfeiffer bacilli shifted from para non-indol-forming to indol-forming types during epidemics.
• Pneumococci incidence increased during the Alabama cold epidemic, and were generally avirulent in Labrador.

Conclusions:

• Respiratory infections are associated with significant shifts in nasopharyngeal bacterial populations.
• Pfeiffer bacilli and pneumococci may play a role in the pathogenesis or response to common colds and tracheitis.
• Community-level studies are essential for understanding the interplay between microbial flora and disease outbreaks.