Seroprevalence of antibodies to chlamydia pneumoniae and legionella pneumophila in mine workers, factory workers and pneumonia patients
Date
1994
Authors
Bartie, Catheleen
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
South African gold-miners work under stressful conditions and live in communal hostels.
Respiratory infections are common in these workers and several cases of Legionnaires'
Disease have previously been diagnosed in workers at a gold mine on the East Rand. The
prevalence of antibodies and the rate of seroconversion within a period of six months, to
C. pneumoniae and L. paeumopbils, both common causes of atypical pneumonia, was
studied in relation to several risk factors including age, smoking habits, previous
underground experience and past exposure to dust and humidity in the environment.
Factory workers from a rural area in Natal and hospitalised patients with community
acquired pneumonia were tested for comparison. Water samples were collected from several
areas at the mine, including both surface and underground samples"
Antibodies to C. pneumoniae were present in 66% of the mine workers, compared to 50%
of pneumonia patients and 22% of factory workers, a statistically significant difference
(P<O.OOl), Seroconversion was demonstrated ill 17% of the mine workers within a period
of six months working underground, and in 22% of pneumonia patients, with convalescent
stage sera taken 1-6 weeks after onset of symptoms. None of the risk factors studied
influenced the prevalence of C. pneumoniae antibodies in the mine workers, but a
significant association between the presence of respiratory symptoms in the six month
period and seroconversicn was demonstrated (P<O.025).
Using heat- killed antigens, antibodies to L. paeumopbile serogroups 1-4 were demonstrated
in 36% of the mine workers, in 16% of the pneumonia patients and in 10% of factory
workers (P<O.OOl). Seroconversion occurred in 18% of mine workers and in 14% of
pneumonia patients. An association could not be demonstrated between any (if the risk
factors studied and the prevalence of antibodies or the rate of seroconversion to L.
pneumophila in the mine workers.
No legionellae were cultured from the water samples, and the presence of these organsims
in chlorinated water from both surface and underground samples could not be confirmed.
Description
A dissertation submitted to the Faculty of Medicine of the University of the
Witwatersrand. Johannesburg. for the Degree of Master of Science in Medicine
Johannesburg 1994