Study of respiratory symptoms among sputum positive

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Pulmonary tuberculosis
Transmission of pulmonary tuberculosis:
For many years tuberculosis was thought to be transmitted
genetically and even today patients who have little or no idea oftheory of
infection when informed of the diagnosis of tuberculosis may express
surprise because it's not in may family doctor (Seaton et aI., 1989).
Riley (1974), found that tuberculosis is transmitted by air borne
spread from person to person via infected respiratory secretions. Inhalation
of droplet nuclei containing the tubercle bacillus may result in infection.
Respiratory droplets are produced when someone with pulmonary
tuberculosis coughs or in the case of laryngeal tuberculosis, with speaking
or singing, While these respiratory droplets are air borne, water evaporates,
leaving 1-5 urn particles called droplet nuclei. Because oftheir small size,
these droplet nuclei may remain suspended in air currents for hours and,
when inhaled may escape the host's. When these droplet nuclei reach the
alveoli infection may result (Riley, 1974).
Infectiousness ofa tuberculous patient is dependent on the number of
tubercle bacilli expelled into the air. The bacilliary load is related to a
number of factors, including presence of disease in the lungs, cavity
formation, disease in the airways or pharynx, presence or induction of
cough. Failure of the patient to cover the mouth while coughing, and
presence of AFB on microscopic examination ofsputum specimens. The
period of infectiousness may be prolonged with in appropriate therapy of
tuberculosis (CDC 1990).
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