Why Bird Proof
Disease potential which exists when birds such as pigeons are permitted to roost in areas frequented by humans. For example, pigeons roosting and nesting on roofs, around air conditioning systems, in steeples etc.
Apart from the disease hazard, wet bird droppings are slippery and can lead to people slipping and falling onto solid surfaces such as sidewalks. Bird roosts are frequently infested with flies as well as several species of parasites such as bird mites, ticks etc., which bite humans, & can readily cause infection. Bird roosts are also smelly, the presence of accumulated bird droppings can block gutters and drains and the acidity in bird droppings causes permanent damage to metal surfaces, painted surfaces etc. Quite often the cost of repair and replacement of damaged surfaces exceeds the cost of exclusion.
The white material you see in droppings is uric acid which is a very powerful acid. It will eat through steel, the final finish on automotive paint etc. and cause permanent damage. In addition, there are yeasts which live in bird feces and as these yeasts live they also excrete acids. So wherever you have bird feces you have the on-going generation of powerful acids and their corrosive effects.
There are over 40 known virus and 60 diseases directly associated with birds and their droppings. These diseases vary in seriousness from minor stomach ailments to fatal diseases such as histoplasmosis, which is the one disease which is now most common.
Histoplasmosis is a fungus which is found in the soil, particularly soil with a high nitrogen content and it is enriched by the droppings of birds and bats. It thrives in warm temperatures and in moist conditions especially in areas such as bird roosts, caves infested with bats, school yards, chicken coops, areas where there is rotten or decaying wood etc. It is contracted when the soil from an infected area is disturbed and tiny spores are inhaled. These spores enter the lungs and can then be transported around the body.
Birds can carry histoplasmosis fungus on their legs, feet, wings etc. but they are not infected with histoplasmosis, most likely because of their high body temperature. However bats do carry and do excrete histoplasmosis. Apart from humans, animals such as dogs, cats, rats, skunks, foxes etc. also are susceptible to this disease.
It is estimated that in n America alone, 50 million people have been infected with this fungus, approximately 500,000 test positive each year and we have about 800 deaths.
It usually appears as mild, flu-like symptoms, chest pain, dry cough etc. A chest X-Ray will show a very distinctive pattern like “snowballs”.
Dust and dirt containing histoplasmosis spores can be carried over a long distance and hence can affect a number of workers on an infected site.
Once airborne, these spores can be carried for quite long distances by the wind. It was such an activity which caused the three largest known outbreaks of Histoplasmosis on record and all occurred in Indianapolis.
1978; 120,000 people infected and 15 died.
1980; similar to 1978
1988(50% of the cases were AIDS sufferers)
In 1978 the American Journal of epidemiology reported that workers were shoveling excessive bird droppings from the roof of a courthouse to the ground for removal. The dust from this procedure was picked up by the window air conditioners and re-distributed throughout the entire building. Over 50% of the occupants contracted Histoplasmosis and one person had only been in the building for 10 minutes.
Several cases of Cryptococcocal meningitis have been reported where workers exposed to bird droppings have developed a chronic inflammation of the brain tissue. A window cleaner in California lost 50% of his lung capacity because he came into regular contact with bird droppings on window ledges.
TRANSMISSION OF DISEASES FROM BIRDS TO HUMANS
SALMONELLOSIS
Salmonella live in the intestines of birds and other animals and is transmitted to humans by ingesting food containing this bacteria. Food can also be contaminated by passing the bacteria from our hands which have touched a surface containing this bacteria.
40,000 cases of infection from the salmonella bacteria are reported each year in the USA and 1,000 deaths per annum.
People develop fever, abdominal cramps, diarrhea etc. usually lasting from 4-7 days. Severe cases require hospitalization.
Avoidance: remove birds from buildings especially if they are nesting and dropping faeces on or around air conditioning systems. Wash hands thoroughly if you touch any surface where bird droppings are present.
For more data: www.cdc.gov/od/oc/media/fact/salmonel.htm
ARBOVIRAL ENCEPHALITIDES
These are viruses which survive through the transmission from host to host by blood suckers such as mosquitoes, ticks etc. They cause encephalitis in humans. Most occur in the period June-September but it is much more extensive in the warmer climate States.
Symptoms include fever, headache, malaise, etc. Some deaths do occur. There is no commercially available vaccine for this virus.
One strain (EEC) occurs in natural cycles involving birds. Grain eating birds such as sparrows, pigeons etc. are thought to play a role in the transmission of the virus (W.E.E.) to mosquitoes then to humans. Mortality rate is approximately 3%.
For more information www.cdc.gov/ncidod/dvbird/arbor/arbdet.htm
ST. LOUIS ENCEPHALITIS
People develop flu-like symptoms, fever, headache, lethargy etc. Severe cases cause seizures, double-vision, paralysis and death. As many as 30% of elderly people infected with SLE die.
No vaccine is available; No antibiotics are effective; No cure.
This virus occurs naturally in birds however it does not affect them. It is spread from bird to humans by blood sucking mosquitoes type “CULEX” which are very common in the USA.
Prevention is best achieved by removing roosting and nesting birds from buildings where people live and work. Culex mosquitoes are most active between 1 hour before sunset to one hour after sunrise. They breed in fresh water and are prevalent after rain.
For more information www.vicioso.com/health/disease/encephalitis/sle.htm
WEST NILE VIRUS
Since 1999 this virus has been found in over 80 species of birds, including 60 free ranging species from 20 States. As the virus spreads to more locations in Gulf Coast States, the threat of the virus spreading to Midwestern and Western states becomes greater.
Birds found infected include the Rock Dove (Pigeon).
West Nile Viral infections are rapidly increasing in intensity and distribution in the USA. The southward migration of birds is of particular concern as they will pass through infected States and move the virus to other more Southern States along the gulf Coast. Infected dead birds have been found in 9 new states.
4 human cases have occurred in Florida and 1 death in Georgia. This is in addition to 4 human cases in New York City area, and one in New Jersey. In 2000 there were 21 human cases with 2 deaths and in 1999 there were 62 human cases with 7 deaths.
To protect the health of people, roosting and nesting birds should be removed from properties where people work and live, especially in the Eastern States at the current point in time. Precautions against mosquito bites should also be taken.
For more information www.usgs.gov/public/press/public_affairs/press_releases/pr1109m.html.
HISTOPLASMOSIS
Histoplasmosis is a fungus which is found in the soil, particularly soil with a high nitrogen content and it is enriched by the droppings of birds and bats. It thrives in warm temperatures and in moist conditions especially in areas such as bird roosts, caves infested with bats, school yards, chicken coops, areas where there is rotten or decaying wood etc. It is contracted when the soil from an infected area is disturbed and tiny spores are inhaled. These spores enter the lungs and can then be transported around the body.
Birds can carry histoplasmosis fungus on their legs, feet, wings etc. but they are not infected with histoplasmosis, most likely because of their high body temperature. However bats do carry and do excrete histoplasmosis. Apart from humans, animals such as dogs, cats, rats, skunks, foxes etc. also are susceptible to this disease.
It is estimated that in n America alone, 50 million people have been infected with this fungus, approximately 500,000 test positive each year and we have about 800 deaths.
It usually appears as mild, flu-like symptoms, chest pain, dry cough etc.
Dust and dirt containing histoplasmosis spores can be carried over a long distance and hence can affect a number of workers on an infected site.
The three largest known outbreaks of Histoplasmosis on record are:
1978; 120,000 people infected and 15 died.
1980; similar to 1978
1988(50% of the cases were AIDS sufferers)
In 1978 the American Journal of epidemiology reported that workers were shoveling excessive bird droppings from the roof of a courthouse to the ground for removal. The dust from this procedure was picked up by the window air conditioners and re-distributed throughout the entire building. Over 50% of the occupants contracted Histoplasmosis and one person had only been in the building for 10 minutes.
Several cases of Cryptococcocal meningitis have been reported where workers exposed to bird droppings have developed a chronic inflammation of the brain tissue. A window cleaner in California lost 50% of his lung capacity because he came into regular contact with bird droppings on window ledges.
People are strongly advised to remove birds from roosting and nesting on buildings especially if they are near air handling systems.