Indirect Airborne

Indirect Airborne

Indirect Airborne
Most of the larger droplets expelled during talking and coughing become dried particles of dust on exposed surfaces or on clothing, bed cloths or handkerchieves. If they contain respiratory pathogens that resist natural drying, this dust when raised in the air during activities such as dusting, sweeping, bed-making or shaking of a handkerchief could be inhaled and may set up infection. Dust-borne spread has been proved for certain viral and rickettsial infections such as psittacosis and Q fever. Dust particles can harbour various pathogens.

Staphylococci and streptococci can survive on dust and be transmitted by the airborne route. Spores produced by certain fungi are also transmitted by the airborne route and can cause such diseases as histoplasmosis; coccidioidomycosis and blastomycosis.

A number of potentially pathogenic microorganisms are part of the normal microbiota in the upper respiratory tract. They do not cause illness because the predominant microorganisms of the normal microbiota suppress their growth by competing with them for nutrients and producing inhibitory substances.

Airborne pathogens make their first contact with the body's mucous membranes as they enter the upper respiratory tract. Many respiratory and systemic diseases initiate infections here.

Home | Site map | Submit Article | Directory | Search