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If you ever had an odor or indoor air quality issue within your facility you can appreciate the difficultly in identifying the sources or causes and responding to questions from employees.

Health Issues

Friday, March 8, 2013
Health Issues What You Should Know About Birds and Bats

Health Issues: What You Should Know About Birds and BatsBuildings are the preferred roosting and nesting spots for many types of birds such as pigeons, sparrows and starlings, as well as for bats.

Interestingly, while these birds are typically solitary nesters and do not form and develop colonies, bats on the other hand do form colonies that can be very large and cause significant impacts on a building’s structure and on the health of its occupants from the following organisms:

  • Histoplasma capsulatum
  • Cryptococcus neoformans
  • Chlamydophila psittaci

Health Issues: What You Should Know About Birds and BatsHistoplasmosis is caused by a fungus (Histoplasma capsulatum) and is transmitted to humans by airborne spores from pigeon and starling droppings as well as bats. Infection occurs when spores, carried by the air, are inhaled.

Most infections are mild and produce either no symptoms or a minor influenza-like illness. On occasion, the disease can cause high fever, blood abnormalities, pneumonia and even death.

The disease-causing fungus Cryptococcus neoformans is primarily found in accumulations of pigeon droppings around roosting and nesting sites, for example, attics, cupolas, ledges and water towers. The fungus has been found in as much as 84 percent of samples taken from old roosts.

Even when old and dry, bird droppings can be a significant source of infection. Like histoplasmosis, most cryptococcosis infections are mild and may be without symptoms. Persons with weakened immune systems, however, are more susceptible to infection.

Chlamydophila psittaci is a bacteria that can cause infection when a person inhales organisms that have been aerosolized from dried feces or from the respiratory tract secretions of infected birds. Psittacosis is the disease caused by the Chlamydophila organism. This disease is rare and not as common as histoplasmosis or cryptococcosis. It is noteworthy that avian influenza viruses typically do not infect humans; however, several instances of human infections and outbreaks of avian influenza have been reported since 1997. No infections in humans have occurred in the United States. It is interesting to note that fungi and bacteria that grow on residue (droppings, food, feathers, etc.) left by birds and bats are more of a health hazard to the occupants of buildings than is the avian flu. This is primarily due to the fact that fungi, bacteria, dust mites and other organisms thrive in the residue.

Health Issues: What You Should Know About Birds and BatsIn addition to the specific diseases, droppings, feathers, food and dead birds and bats under a roosting area result in bacteria and mold growth, harbor dust mites, and can breed flies, and other insects that may become major problems in the immediate area and can result in significant air quality concerns and issues.

For more information on this topic please contact Chris Schneider, CIH, at 610.524.5525, ext. 14, or email.