Zoonosis

I see the occasional post on Facebook chicken groups in which someone relates their symptoms of their illness and asks if it could have been transmitted by their chickens. Most of the time the answer is a clear ‘no’. There are, however, some things that you can pick up from your birds.

You are more likely to get sick from handling poultry in your kitchen than your live birds. These are three illnesses that are spread by food contamination:

Campylobacter is a bacterium that spreads to people through contaminated food (meat and eggs), water or by touching poop of infected animals. Your chickens can carry it without showing any signs of illness. Symptoms in people are: diarrhea, cramps, abdominal pain and fever 2 to 5 days after exposure. It is also linked to serious life-threatening infections such as Guillain-Barré syndrome in infants, elderly people, and those with weak immune systems.

E.coli, a large and diverse group of bacteria, is found in the environment, food, and intestines of people and animals, including poultry. Most strains are harmless, while some can make us sick: diarrhea, urinary tract infections, respiratory illness and pneumonia. E. coli that can cause illness in people can be spread through contaminated water or food, or through contact with infected animals or their poop.

Salmonella spreads to people through contaminated food (eggs and meat) or animal poop, including small flock chickens. Birds can acquire Salmonella from a contaminated environment or feed, carrier rodents, insects, and may have Salmonella in their poop and on their bodies (feathers, feet, and beaks), even when they appear healthy and clean. While it usually doesn’t make the birds sick, it can cause serious illness when it is passed to people: diarrhea, vomiting, fever and abdominal cramps. Infants, the elderly, and those with weak immune systems are more likely than others to develop severe illness.

These viruses can be spread by contact with infected birds:

Avian Influenza, or Bird Flu, is caused by Type A influenza viruses, which are classified into subtypes based on the two proteins on their surface, hemagglutinin (H) and neuraminidase (N). These viruses occur naturally among wild aquatic birds worldwide, and can affect poultry, domesticated and wild birds. They don’t always show signs of infection, but poultry flocks can experience a range of symptoms from decreased egg production to extremely high death rates.

A.I. viruses can be broadly classified into two types, based on the severity of the illness caused in chickens in a laboratory setting:

• Low pathogenic avian influenza (LPAI): Most strains of A.I. are low pathogenic and cause little or no signs of illness in infected poultry.
• Highly pathogenic avian influenza (HPAI): viruses can cause severe illness and death in poultry flocks.

Periodically, Avian Influenza makes the headlines as outbreaks pop up in human populations. A couple of weeks the hot spot was Suffolk, England where 27,000 chickens at one commercial farm were culled to prevent the spread of a LPAI-strain of the virus between birds.

A.I. is rare in humans and generally doesn’t spread easily between people; however, limited clusters of person-to-person transmission, generally between family members, happens.

Strains of A.I. that kill poultry may not make people sick, and conversely, strains that affect people might not be problematic for poultry. No severe human illnesses caused by bird flu have been reported in the United States; people in Africa, Asia, and Europe have been infected. There was one death reported in Canada in 2014 involving someone who had recently visited China and transported the virus back with them.

In people, symptoms can range from fever, muscle aches, and conjunctivitis to severe respiratory distress, pneumonia, organ failure, and death.

West Nile Virus is carried by birds and spread by mosquitoes. People, birds, and horses get WNV infection by being bitten by a carrier mosquito. Although many birds, such as poultry, show no signs of infection, the virus can kill some birds, such as crows. Once infected, people can have a wide variety of symptoms, ranging from flu-like illness to seizures, and even death.

Although not a zoonotic infection, some folks will develop allergic reactions to their birds. They may react to avian proteins contained in dander, feathers, skin, urine, saliva, serum and any contaminated feed or bedding materials. Exposure can be through inhalation and contact with skin, eyes and mucous membranes, resulting in: nasal discharge and congestion, conjunctivitis, tearing and itchy eyes, skin redness, rash or hives, coughing, wheezing and shortness of breath.

Many years ago, I got shots for several environmental allergies, including feathers. I must have outgrown my allergies because I now sleep with a feather pillow and have no issues with my chickens.

I met Joan last winter when she contacted me about finding homes for her flock. She suffered from respiratory issues that were exacerbated by having chickens (e.g. dander, dust) and her doctor had advised her to re-home her chickens immediately. Since doing so, some of her symptoms have improved.

Transmission of zoonotic diseases from animals can occur by direct contact; indirect contact with insect vectors and contaminated objects; oral ingestion or inhalation of aerosolized materials.

We can protect ourselves from most diseases by using the following basic hygiene procedures:

• Practice Food Safe guidelines in your kitchen.
• Wash your hands after handling your birds or equipment used in your coop.
• Wear gloves when handling animals, animal tissues, body fluids and waste. Keep animal areas clean and disinfect equipment after using it on animals or in animal areas.
• Don’t eat, drink or smoke while handling animals or when in their pens or coops.
• Wear respiratory protection, when appropriate.
• Practice biosecurity so you are not tracking pathogens from one pen to another, or more importantly, from one farm to another.

I think when it comes to attitudes about hugging chickens we’ll probably fall into two camps. Some folks handle their birds a lot or even have house chickens. I spend lots of time with my flock, but don’t pick them up much, or kiss them. That’s just me. If you’re into that just be aware of the pathogens they might carry and to wash your hands thoroughly after contact. With the increasing popularity of small flocks we will, of course, see an increase in rates of salmonella. Those numbers are still low, and most folks feel the therapeutic benefits of close contact with their birds outweigh the risks of what their flock might pass on.