Bird flu is a zoonosis and domestic cats are getting it in Poland

At the moment, the word "zoonosis" is being used quite a lot in online news media and I'll tell you why. "Zoonosis" means an infectious disease that is transmitted between species including from animals to humans or from humans to animals. This would also be described as a zoonotic disease.

And as it happens, it is not only the news media who are reporting on bird flu which is a zoonosis as the Centres for Disease Control and Prevention (CDC) report that bird flu has been found in Polish domestic cats. You may have read about this but it is interesting that CDC are reporting on it.

Beware the zoonosis bird flu. Image: MikeB

And the word "zoonosis" is an important word today because it was first used a lot during Covid-19. And the reason for that is because Covid-19 is also a zoonosis as it can be transmitted from animals to people and people to animals. It's the way that tigers and lions at some zoos caught the disease from their zookeepers. Some people still think cat owners can get it and are getting from their cats.

And there is a general concern that another pandemic may start up from the transmission of an unknown disease in a wild animal to a human.

And in this instance, an outbreak of H5N1 bird flu in household cats was recently reported by the World Health Organisation. The news underlines the fact that this virus can infect and cause illness in household pets.

The report is that 34 domestic cats across eight provinces in Poland tested positive for avian flu influenza A otherwise known as H5N1 bird flu.

Sadly, many of the infected cats had symptoms of neurological damage. There symptoms included paralysis and seizures. They became severely ill or died. Bird flu is widespread globally among domestic poultry and wild birds and it's caused the occasional infection in mammals.

The risk assessment to humans, despite the above report, is low and CDC states that there is no evidence of cat-to-cat transmission. In general, domestic cats rarely become infected with H5N1. When they do it is most often after eating raw, sick or dead infected wild birds or poultry or they live in an environment contaminated by these birds, perhaps on a farm.

Apparently, among the infected cats most of them lived inside with some outdoor access but some were primarily outdoor cat which will leave them likely to be exposed to wild birds if they were keen predators as most domestic cats are.

It is also reported that some infected cats were fed raw poultry or poultry parts. Of the 34 infected cats, 11 died from their infection and 14 were euthanised because of the infection. The exact source of H5N1 of exposure is unclear in this instance.

I have written about raw cat meat. Bird flu is one reason why raw meat is risky as a cat diet.

Toxoplasma gondii protozoan parasite hijacks immune cells to travel around body

The toxoplasma gondii protozoan parasite hijacks immune cells in order to effectively travel around the body of its host without being attacked by the immune system. In the words of the researcher this is what happens: "This work reveals how an intracellular parasite hijacks chemotaxis in phagocytes and highlights a remarkable migratory plasticity in differentiated cells of the mononuclear phagocyte system".

The author on the PHYS ORG website in referring to the science calls it "identity theft" and they conclude that it is this identity theft which is the secret of this parasite's success. Toxoplasma gondii is in a lot of people and a lot of cats. It is zoonotic. That means it can be transferred from animals to people.

An immune cell that has been infected by Toxoplasma parasites (red). Photo: Professor Antonio Barragan.

The parasite injects the protein into the nucleus of the immune cell. This changes the cell's identity, which tricks other cells into no longer recognising the immune cell as an immune cell. It changes the behaviour of the immune cell allowing it to travel around the body.

In the opening paragraph I've used the word 'chemotaxis'. This word describes a phenomenon in which the direction of a cell's locomotion determined by an extracellular gradient of chemicals. It is the migration of cells towards attracting chemicals and away from repellents.

The toxoplasma gondii protozoan hijacks this process which allows it to travel around the body. It is another way of describing the process of survival of this successful parasite. 

A lot has been written about toxoplasma gondii. A lot of people who hate cats write about it and say that it causes schizophrenia in people because the protozoan migrates to the brain of people and alters their mental processes. They say those things to denigrate the domestic cat.

I don't think that there is hard science to support that statement. Briefly, cats are a secondary vector for this parasite, and they are likely to acquire the infection by consuming infected birds or rodents and sometimes but rarely ingesting oocysts from contaminated soil.

People can get the disease from eating raw or undercooked pork, beef, mutton or veal or unpasteurised dairy products that contained toxoplasma organisms. They can also get the disease by mishandling domestic cat faeces in which there are oocysts. Infective oocysts are only passed for a very short time, however.

The disease is normally asymptomatic i.e., without symptoms. The most common signs of toxoplasmosis in domestic cats are loss of appetite, lethargy, cough and rapid breathing. There may be neurological signs. The lymph nodes may enlarge. Kittens may exhibit and encephalitis, liver insufficiency or pneumonia.

RELATED: Health tip: preventing a toxoplasmosis infection from cat faeces.

Prenatal infection may be responsible for abortion and stillbirth. Many cats show clinical signs that are concurrent with feline immunodeficiency virus or feline leukaemia virus.

People are frightened of this virus because it is zoonotic, as mentioned. It's important to understand the mode of transmission from cats "to understand how minimal the risk is" (Cat Owner's Home Veterinary Handbook).

Even a cat with an active toxoplasmosis infection is only capable of passing it on for 7 to 10 days of her entire life when there is an acute infection.

The experts will say that there is no need for pregnant women to get rid of their domestic cat companion. They can take precautions to avoid contact with faecal material from cats by for example wearing gloves when gardening and cleaning the litter box.

I have written many pages on this disease which you can access by clicking on this link.

More than 36 out of 5000 tests on cats and dogs proved positive for Covid

The Sun Sentinel tells us that one manufacturer providing Covid PCR tests for pets, IDEXX Laboratories, tested over 5,000 specimens from dogs, cats and horses. All of the animals had respiratory health issues. The tests confirmed that more than three dozen cases of Covid in either a dog or cat were positive. It appears that they had caught Covid from their human caregiver. This is a report from Florida and therefore these are Floridian cats.

More than 36 out of 5000 tests on cats and dogs proved positive for Covid. Image: MikeB

What is the interest? This is the first time that I have seen a measured percentage of cats and dogs contracting Covid from a large sample. Unfortunately, the report does not drill down and tell us the percentage for cats and for dogs. 

They have merged the two species. Nonetheless, 'more than 36' might be around 40 so 40/5000 is 0.8%, in percentage terms. That of course is less than 1%. So, we can say on the basis of this skimpy report that less than 1% of cats and dogs get Covid from their human caregiver in Florida. A very low figure.

It may be possible to extrapolate that information to other parts America but it might not be wise to do so. The information is useful because we can date it to January 2022. 

This is a time when the Omicron variant has spread rapidly. It is less severe but more contagious than the previous Delta variant. It is a sort of snapshot at a certain date about a certain variant and its impact on two species of companion animal. That might be useful to some people which is why I am reporting it.

No Covid vaccinations for pets because they aren't a priority

NEWS AND COMMENT: We, the public, know that lions, tigers and bears have been given Covid vaccinations. This tells us unequivocally that there is a Covid vaccine for animals, specifically zoo animals. This is because zookeepers who have been infected with Covid transmit the disease to captive animals at their zoo. This is important because the animals are valuable. They are an asset to the zoo and that asset needs to be protected with a vaccine.

RELATED: Tragedy: 3 snow leopards die of Covid

Free pet care clinic Seattle 2020. Ruth Fremson / The New York Times

However, despite the knowledge of an effective vaccination for animals, vaccines are unavailable for dogs and cats. This is simply because, on my understanding, that dogs and cats are de-prioritised.

The experts think that cats and dogs do not transmit Covid to their owners and other people living in their homes. One veterinarian, Dr. Elizabeth Lennon, working out of the University of Pennsylvania said that she is frequently asked when a vaccination will be made available for domestic cats and dogs.

The answer is that pets are simply not a priority according to experts. Dr. Lennon said that:

"To date, there hasn’t been any documented cases of dogs or cats spreading the virus to people."

And Dr. Will Sander, a veterinarian at the University of Illinois at Urbana-Champaign said that the risk of the disease spreading in pets is so low that any vaccine would not be worth giving.

RELATED: Can domestic cats transmit Covid?

This is a question of economics and finance and whether people can be bothered to vaccinate companion animals. At the moment the answer is that it is not worth vaccinating them.

My research does not specify absolutely that the vaccines given to zoo animals can be used on domestic animals. However, I can't see any reason why a vaccine used on a big cat like a tiger can't be used on a domestic cat. This is because they are exactly the same anatomically with some very minor differences excluding the size difference which is obvious. 😀.

But the point is that they are the same and they have the same physiology, so I would like someone to tell me why the vaccines made available to zoos in America can't also be made available to veterinarians. Is that such a big ask?

Even if the vaccine is de-prioritised for pets, it is hardly a great difficulty or burden to distribute it a little more widely to veterinarians.

Source: Seattle Times.

Cats and dogs often catch Covid when their owners are infected

The word "often" in the title is a bit startling. It was known that cats can get the disease from their owners but until recently it seems we did not know how common this was. But now we do because according to research at Utrecht University in the Netherlands, six cats and seven dogs tested positive for the disease and 54 pets were found to have antibodies to the disease out of a total of 310 pets tested in 196 households. 54 pets out of a total of 310 is 17%. The research indicates that 17% of cats and dogs get the disease from their owners if their owners have suffered from the disease.

Cats can get Covid from their owners in bed. Photo: Photo: crisisangels, via lorenzens-soil.

This I think is useful information. It indicates that, as stated, it is quite common for owners to transmit the disease to their cats and dogs. It makes you wonder whether the virus might become a reservoir in those companion animals and pass it to visitors to the owners' homes. I'm sure this is being considered by scientists.

Disappointingly, the director of the University's Veterinary Microbiological Diagnostic Centre said that the purpose of the research was to protect people not the animals. He said that humans rather than pet health was the main concern for the researchers. I don't like that. I wouldn't like that because I'm an animal advocate. I can't see why he can't be equally concerned that animals and people. What is wrong in saying that?

He did go on to say that "if you have Covid, you should avoid contact with your cat or dog, just as you would with other people". This is not going to happen. One reason is because people just don't keep up-to-date with research on Covid such as the research I'm referring to here. Another reason is that people cannot stay away from their cats and dogs because they are too important to them.

The good thing, as mentioned in earlier articles is that pets tend to be asymptomatic or at worst, they display very mild Covid symptoms. And all the research points to the transmission of disease from people to people and people to animals but not animals to people. Although, I suspect that when further research is done on that they will discover that companion animals transmit the disease to people. Watch this space.

The researchers say that, "We can't say there is a 0% risk of owners catching Covid from their pets. At the moment the pandemic is still driven by human-to-human infections, so we just wouldn't detect it."

The research also found that when pets sleep on the bed of their owners, they are more likely to catch the virus from their owners. It might work in the other direction as well. A lot of people let their cats sleep with them at night as I do. I don't think this information will change their habits. Those that don't allow it will be reinforced by this information.

Dorothee Bienzle, a professor of veterinary pathology at the University of Guelph said tellingly, "If someone has Covid-19 there is a surprisingly high chance they will pass it on to their pet. Cats, especially those that sleep on their owner's bed seem to be particularly vulnerable."

She recommends people keep away from their pets! It won't happen so don't bother to mention it.

Domestic cat contracts TB from badger

A domestic cat in Ireland contracted TB from a badger which had been vaccinated with the BCG vaccine. I don't have any more information as it is reported on one website: fginsight.com but that site requires registration to access their content. The report is troubling as I think it is the first report that I have seen of a domestic cat contracting TB from a badger. 

Image by OpenClipart-Vectors from Pixabay 

The information would seem to be at least potentially of a real concern to domestic cats anywhere particularly in countries where it is normal for domestic cats to be indoor/outdoor cats as in the UK. I am particularly aware of this hazard as I put out food for foxes and I also know that a couple of foxes and a couple of badges eat the food. 

Thirdly, my cat walks around the same places as these wild animals. Is there a chance that my cat could contract TB? I think that it is highly unlikely but the story tells us that there is a possibility.

Although the document is undated (presumed middle of 2020), and article online from the University of Edinburgh tells us that they were investigating a cluster of TB infections in cats which may have been linked to a certain type of raw pet food. I wrote about this at the time - click here to read the article. 

They also say that most cases of TB in cats are caused by infected bites. The prevalence is low in the UK, in that they write: "More than a hundred cases of TB in cats are reported in the UK each year. The majority are caused by infected bites from wild animals."

This seems like a very low number and they don't report that TB can be transmitted from cattle to domestic cats.

Australian scientist claims that diseases transmitted by cats to people cost the Australian economy AU$6 billion annually

I find this extraordinary. Unfortunately I don't have access to the full article by Donna Lu on the newscientist.com website because you have to subscribe to the site and I don't want to do that (but see update below please). But the opening paragraphs state that diseases transmitted by the domestic cat to people, including cat scratch disease, cost the Australian economy more than AU$6 billion per year (4.2 US dollars). The costings are based upon the impact on human health and livestock production. Clearly they are inferring that domestic cat spread disease to livestock as well or is it that people are incapacitated and therefore can't farm? They may be referring to toxoplasmosis. No doubt they are because this disease always comes up in these sorts of discussions. The author emphasises cat scratch disease and bites.

Prof Sarah Legge. Photo: Australian National University.

Well, there you are. I will have to speculate as to how they have calculated this cost. But they must be saying is that cat owners and non-cat owners are being bitten or scratched by domestic and stray cats which removes them from the workplace for a day or two while they recover. Or perhaps they go to hospital but this is normally extremely rare.

99% of cat bites and scratches do pretty well nothing in terms of interfering with one's day-to-day living. That's my personal experience. Toxoplasmosis is almost always asymptomatic in people i.e. no symptoms. Cat scratch disease is rare in people. Certainly, cats can cause it but I would speculate that one in 500 or 1000 scratches results in cat scratch disease. It needs to be treated. Bites are not uncommon but most often are irritations more than injuries that need to be dealt with immediately. That said when bitten by a cat you have to be vigilant and watch the area where you were bitten. As soon as it looks as if it's becoming infected you must take antibiotics as prescribed by a doctor to ensure that they are the right antibiotics. This is an absolute must as stated. Because if you let an infection caused by a cat bite get worse it can cause a serious injury and it can lead to hospitalisation.

Zoonotic diseases transmitted by cats to people are on the whole pretty rare and therefore have difficulty in understanding how they arrive at a AU$6 billion cost.

Update

I have found an article on a Chinese website which discusses the research by Prof Sarah Legge of the Australian National University and the University of Queensland. She argues that annually over 500 people die in Australia and there are 11,000 hospitalisations due do diseases transmitted by cats to people. The costs include medical treatment, reasonable relevant expenses, lost income et cetera.

She refers to toxoplasmosis as mentioned, roundworm and cat scratch disease. Of these toxoplasmosis has the biggest negative impact on the Australian economy. She claims that it has possible long-term effects on behaviour and mental health. Note, the word "possible". She doesn't know and therefore how can she make calculations on the back of it.

She claims that the parasite that causes toxoplasmosis causes 200 deaths and 6,500 hospitalisations due to car accidents which could be avoided in Australia annually. She believes that the disease causes mental health disorders which I presume are translated into poor driving! She claims that one in five cases of schizophrenia and one in 10 cases of suicide were caused by toxoplasmosis. She wants domestic cats to be kept indoors all the time in Australia and for people to wash their hands thoroughly after handling cat litter or gardening. This is to stop transmission of toxoplasma gondii oocysts in the soil or faeces in the litter tray to the hands and from the hands to the mouth and therefore ingested.

She also claims that feral cats around towns are a reservoir for disease.

Human behavior

We have to discuss human behaviour in this equation. Most cases of toxoplasmosis are caused by mishandling of raw foods in the kitchen. That's due to careless human behaviour. Being scratched or bitten by cat is often put down to careless human behaviour. Contracting toxoplasmosis through mishandling of cat litter or when gardening, once again, can be put down at least in part two careless human behaviour. Therefore this vast economic loss to the economy in Australia as stated is in large part due to human behaviour. It is unreasonable to blame the cat exclusively as this professor is.