|  | Funny you should mention carrots, Brian.  Check out the last bullet in the 
recommendation section of the following article.
A columnist for Bird Talk magazine (and DVM) has received a copy of the 
study and considers it to be a valid study.  The following article is from 
the February 1993 Bird Talk, page 61 (copied without permission).  
I'd like to add that if ANYONE wanted to hush up this study, it would be 
organizations like magazines whose readerships are bird owners.  I'm glad 
Bird Talk had the guts to address this issue.
Roseanne
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BIRD TALK Magazine
Causes and Cures
by Margaret Wissman, D.V.M.
Lung Cancer Linked to Birdkeeping
  We have received many letters from concerned bird owners since the 
publishing of a recent medical report linking pet bird ownership with 
an increased occurrence of lung cancer.  Many newspapers, both local 
and national, summarized this report in articles.
  Before allowing this study to cause a panic among bird owners, let's 
analyze the facts.  Dr. Kohlmeier, the primary researcher in this study, 
was kind enough to allow me to interview her directly, and she also 
sent me a copy of her study.  Understandably, the publishing of her 
findings caused an inundation of phone calls and letters to her.  Dr. 
Kohlmeier is a professor of nutrition and epidemiology at the University
of North Carolina at Chapel Hill School of Public Health.
  Previous studies done worldwide show that workers chronically exposed 
to chicken manure have an eightfold increased chance of developing lung
cancer, and that pigeon fanciers can have up to a twentyfold increased
risk.  Another study, researched in the Netherlands, showed that 
keeping birds increased the risk of developing lung cancer.
  Dr. Kohlmeier's study, conducted in former West Berlin, did show a 
link between keeping pet birds and in increased risk of developing lung 
cancer.  The study took into account independent variables such as 
cigarette smoking, passive smoking, vitamin-C intake, beta-carotene 
intake and occupational risks for lung cancer (such as asbestos workers,
miners, metal workers, chemical plant workers, carpet layers and people
exposed to exhaust fumes).  The highest risk for developing lung cancer
comes from, not surprisingly, cigarette smoking.  Occupational workers
exposed to hazardous substances had a threefold increase in lung cancer
risk.
  Comparing bird-owning families to those without birds, the study 
showed that keeping pet birds in the home for one to five years doubled
the owners' risk of developing lung cancer.  Keeping birds in the home
for more than 10 years carried a three- to eighteenfold increased risk.
  These are the facts about the risks of keeping pet birds as presented
in Dr. Kohlmeier's study.  What is not known at this time is WHY 
keeping pet birds constitutes an increased risk of developing lung 
cancer.  
  One theory is that the fungus Cryptococcus neoformans, which can be 
found in pigeon and parrot droppings, can grow in bird cages, releasing
spores into the house, and, when inhaled, these spores set off a chain 
of events in the lungs.  The good news is that in my practice I do not 
often culture Cryptococcus, and I do a lot of fungal cultures.
  The other theory is that bird feathers, feather dust or powder are 
extremely irritating to human lungs, leading to cancer.
  So, whether the droppings or the feather dust are involved, there are
simple ways to minimize risks for bird owners.  In the future, we may
find that simply treating birds with a good systemic anti-fungal 
medication may drop the risk, if indeed the Cryptococcus fungus is 
involved.  I am sure that as a result of this study, more research will
be done in this area of medicine.
  When we better understand the possible risks of pet bird ownership,
we will be better able to advise owners about the manner in which they
keep their birds.  Until that time, Dr. Kohlmeier makes these common-
sense recommendations for bird owners:
* Keep bird cages clean.  Change the papers at the bottom of cages at 
  least every other day.  Do not allow spilled food or water to stand 
  in the bottom of cages.  Break down cages regularly and thoroughly
  clean perches, bars, and dishes.
* Do not let birds fly free in the home.  Keep your birds' wings 
  clipped for your health as well as for the safety of your birds.
* Keep good air circulation in the room where the birds live.  Ventilate
  the room well, and consider using air purifiers or ionizers.
* Consider caging your birds in a room away from your main living areas.
  Exposure time to birds matters.
* Eat a healthy diet.  The study showed that eating carrots, beta-
  carotenes and other anti-oxidants significantly reduced the risk of
  lung cancer from keeping pet birds.  Carrots and beta-carotene 
  (found in canary color-food) can negate the increased risks 
  tremendously when ingested by people.
  Based on this study, I am certainly not getting rid of my beloved pet
pet birds.  What I WILL do, however, is continue to follow sound medical,
health, and hygiene practices.  I will also continue to recommend 
periodic checkups for pet birds, including Chlamydia testing, bacterial
and FUNGAL cultures, to minimize risks of owners contracting diseases 
contagious to humans.  I recommend that bird owners keep their pets' 
cages scrupulously clean, and that they discuss taking a daily beta-
carotene supplement with their human physician.  That canary color food
is looking better all the time.  Now, if you will excuse me, I have to 
go clean bird cages!
 | 
|  |     Not wanting to add to the confusion but still:
    
    I nearly died of Psittacosis some eight years ago. This is a specific
    form of Ornithosis and is a bit more virile.
    It is distributed through dust of dried dropping and inhaled through
    trhe lungs. This is usually the where the infection starts as well.
    In another study done over here in the Netherlands is was found that
    this desease is not uncommon among bird-keepers and is nearly always
    diagnosed as a bad cold.
    Usually the body can cope and there is no increased risc. However if
    in the family of a bird-keeper a case of sudden, very high, fever
    should occur, the bird-keeping should be mentioned to the doctor.
    
    In my case there were non of the usual, indicating, lung problems and
    therefor the desease was incorrectly diagnosed. I was all gone from
    this world so it all went past me. For days I had an extremely high fever
    and I was kept in isolation as they could find no cause. After several
    days of 41.5 degrees centigrade my wife gave permissiondecided to use the
    wide-spectrum antibiotic option. This luckily brought down the temp.
    but might as well have killed me.
    I could return home after 4 weeks hospitalisation. It took another
    three month for me to read a bookpage without forgetting what was on
    the last one. A lot more time went by before I could complete a
    telephone call whilst remembering who I was talking to.
    I did almost recover completely but still have a anomality showing in 
    my EEG, a continuous beep in my right ear and occasionally problems
    concentrating. 
    
    My birds were tested and no infection was found. They had not been the
    source. From an anti-body count they established that my wife had been
    affected too. She however had only been consious of a bad cold. We
    may have picked it up anywhere but from our own birds! 
                     
    Psittacosis is not dangerous and easy to treat IF DIAGNOSED.
    So apart from the very real increased risc of cancer due to the dust be
    aware of Psittacosis as well.
    Nothing to do away your birds for but like looking left and right
    before you cross the street, or like having sex; just use a condom.
    
    Btw: I still keep cockatoos and, like sex, wouldn't dream of parting 
    with it.
    
    Peter
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