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Passive Administration of Monoclonal Antibodies Against H. capsulatum and Others Fungal Pathogens
Published on: February 14, 2011
Outbreak of histoplasmosis among employees in a paper factory--Michigan, 1993
M G Stobierski1, C J Hospedales, W N Hall
1Bureau of Infectious Disease Control, Michigan Department of Public Health, Lansing 48909, USA.
Abstract:
In December 1993, four reported cases of histoplasmosis among employees in a Michigan pulp paper factory prompted an investigation. A cohort of employees was surveyed to identify additional cases. A case of acute histoplasmosis was defined as an influenza-like illness in a plant employee with the onset of illness during October or November 1993 and laboratory evidence of recent infection with Histoplasma capsulatum. Among the 96 employees surveyed, 18 persons met the case definition; all of these had illness onset during the last week of October in 1993. The attack rate among maintenance employees (16 of 53 [30%]) was much greater than that among nonmaintenance employees (2 of 43 [5%]) (relative risk = 6.5; 95% confidence interval = 1.6 to 26.7; P = 0.003). On October 22, a dry, windy day, one maintenance worker swept bird guano, approximately 10 cm deep, from an adjacent roof < 20 m from the maintenance building. The disturbance of the bird guano was the likely event which caused this outbreak. H. capsulatum remains an important pathogen among immunocompetent hosts. We recommended that the plant authorities (i) discourage birds from roosting at the facility and (ii) use safe procedures for the cleanup and disposal of soil contaminated with bird droppings.
Insights
An outbreak of histoplasmosis occurred in a Michigan paper factory in October 1993. Disturbing bird guano likely caused the outbreak, primarily affecting maintenance workers.
Area of Science:
- Environmental Health
- Infectious Diseases
- Occupational Health
Background:
- Histoplasmosis is a fungal infection caused by Histoplasma capsulatum.
- Outbreaks can occur when environmental sources of the fungus are disturbed.
Purpose of the Study:
- To investigate an outbreak of acute histoplasmosis among employees at a Michigan pulp paper factory.
- To identify the source and risk factors associated with the outbreak.
Main Methods:
- A cohort survey of factory employees was conducted.
- A case definition for acute histoplasmosis was established, requiring influenza-like illness and laboratory evidence of recent infection.
- Attack rates were compared between maintenance and nonmaintenance employees.
Main Results:
- Eighteen employees met the case definition for acute histoplasmosis, with illness onset in late October 1993.
- The attack rate was significantly higher among maintenance employees (30%) compared to nonmaintenance employees (5%).
- A maintenance worker disturbing bird guano on an adjacent roof shortly before the outbreak's onset was identified as the likely exposure event.
Conclusions:
- Disturbance of bird guano was the probable cause of the histoplasmosis outbreak.
- Histoplasma capsulatum remains a significant pathogen, even in immunocompetent individuals.
- Recommendations included discouraging bird roosting and implementing safe procedures for handling contaminated materials.
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