The hens are urban-they are the common sources of diseases ?

Jean-François Cliche
The SunLes poules urbaines sont-elles des sources fréquentes de maladies ?

Les poules urbaines sont-elles des sources fréquentes de maladies ?

Les poules urbaines sont-elles des sources fréquentes de maladies ?


29 may 2020 11: 12 am


The hens are urban-they are the common sources of diseases ?

SCIENCE DAILY / “It is known that most viruses that infect humans come from close contact with farm animals or wildlife. So is this the new mode of raising her own chickens (in the city as in the countryside) does not constitute an additional risk for emergence of new viruses ? What are the measures to be taken to prevent the hens, we can transmit diseases ?”, request Mathieu Frégeau from Quebec.

In these times of pandemic, the question that comes most spontaneously to mind is probably : is it that chickens can be a vector of the COVID-19 ? And the answer is clearly no. The virus we infect by attaching to receptors present on the surface of some cells, but such beings are extremely specialized that are able to cling to a single type of receptor very particular — in the case of the COVID-19, it is a receiver named ACE-2. However, the hens do not have a receiver that is sufficiently similar to the ACE-2 human to be able to catch and transmit the disease.

“Still, there are other coronaviruses that affect birds, says Jean-Pierre Vaillancourt, a professor of veterinary medicine at the University of Montreal and a specialist in “zoonoses” those diseases that jump from animals to humans. In the chicken, it creates a bronchitis. In turkey, it is an enteric infection [editor’s note : that affects the intestines]. But these coronaviruses have nothing to do with the COVID-19, which is very different.”

Of course there are other respiratory viruses that chickens can carry and which can attack humans — the famous outbreak of “bird flu”, which we hear about from time to time, are an example. “But quite frankly, if I had to manipulate hens to urban, this would not be my first concern,” said Mr. Vaillancourt. It is technically possible that they are infected, but the odds are extremely slim. First, the vast majority of influenzas in poultry are not zoonotic [editor’s note : they do not infect humans]. When they are, it’s always big stories, but it is very, very rare and you do not have these strains-there here. (…) And there would be several other viruses in hens urban that could potentially make us sick, but it is in probabilities so minute that people in public health don’t care.”

No, if there are microbes that need to really be careful when you raise chickens in his back yard, this is not a virus, but rather bacteria, of which two in particular, ” the researcher warns : salmonella and campylobacters. The first is known to the public because it is a common cause of gastroenteritis (diarrhea, fever, abdominal cramps, etc). It is a bacterium that lives (sometimes) in the intestine of birds, but which can also be found on their paws, their feathers and around their cages, especially if you do not clean regularly.

Salmonella is not very present in the chicken coops, but enough to justify taking preventative measures, such as removing feces every day if possible, wash hands thoroughly after handling the birds, etc (See this guide from the Ministry of agriculture for more details.) An american study has not detected salmonella in only 2 % of houses in urban region of Boston, and yet not a strain of great concern to the human, but an australian study arrived at a figure of 10.4 %.

Les poules urbaines sont-elles des sources fréquentes de maladies ?

Camphylobacters seen in the electron microscope

Wiki Commons

Campylobacters, for their part, are less known than salmonella, but they are no less of bacteria is very common, to the point of being one of the most common causes of food infections. In fact, it is a bacteria that is so prevalent that a study published in 2011 in the scholarly journal Zoonoses and Public Health was detected in 30 poultry houses in urban to 35. These bacteria cause the symptoms of gastro-enteritis, and we should not under-estimate the severity of these infections, warns Mr Vaillancourt — who knows something because he himself had to be hospitalized for campylobacteriosis when it was in the thirties.

“These bacteria are not as infectious as the COVID-19, they are not spread as well to humans, but they are much more durable and they can persist in poultry houses for a lot longer,” said Mr. Vaillancourt.

That said, he adds, the health risks associated with chickens in urban are not, on the whole, to be particularly disturbing. The urban poultry farmers do unfortunately not always the hygiene measures required, and with the growing popularity of this practice, more and more outbreaks linked to chicken coops backyard is reported, but this represents only between 1000 and 1500 cases of salmonellosis per year in the United States, according to figures from public Health american. By comparison, the latter are estimated to be approximately 1.35 million, the annual number of infections with salmonella in the land of Uncle Sam.

“Personally, my first concern when we speak of hens in the city, are the hens themselves, said Mr. Vaillancourt. There are so many people who, for example, find the chicks, although cute at Christmas but that made July 1, will leave behind them moved, like they do with dogs and cats. It has a way to go, in Quebec, on our way to treat animals.”

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