Worms & Germs Blog

US Canine Flu Update

Posted in Dogs

The table below has the latest H3N2 canine influenza numbers from IDEXX Laboratories. Some of the highlights include:

  • Numbers continue to increase. Northern California and Nevada are the hotbeds, with northern CA cases increasing to 343 and Nevada 151. As always, these are just the tested cases, and they presumably represent a small minority of affected dogs.
  • Expansion of flu continues in northern California, with spread to the north, east and south.
  • The concern about LA has decreased for the moment, as the previously reported LA case turns out to have been a dog from northern CA. However, if it keeps spreading, southern CA is certainly in the line of fire.

What about the Ontario situation? So far, things seem to be under control. No further cases have been identified outside the two initial clusters. While the risk remains, it’s possible that canine flu is no longer in the country (knock on lots of wood).


Zinc, pigs and the meaning of antimicrobial stewardship

Posted in MRSA/MRSP, Other animals

Bacteria are smarter than we give them credit for.
Or maybe we’re not a bright as we think we are.

Antimicrobial stewardship is sometimes (wrongly) assumed to simply be the practice of “using fewer antimicrobials,” but it’s more complex than that, because the issue is complex. At face value, overall reduction in antimicrobial use is a logical target, and it’s true that it is a big part of stewardship. However, what is an “antibiotic?” “Raised without antibiotics” and “Antibiotic-free” are flashy marketing terms, but what do they mean in terms of antimicrobial resistance? That’s less clear. In pig production, control of post weaning E. coli diarrhea is a big problem. Prophylactic antibiotics are effective for this, but their use is not ideal. The main thing that’s done to replace antibiotics and still maintain control of the disease is to add a lot of zinc to the piglets’ diets at that age.

  • The reason: zinc still kills bacteria, even though it’s not a conventional antibiotic.
  • The problem: bacteria don’t care whether we call it an antibiotic or not, just that it’s trying to kill them. So, they try to resist it.
  • The bigger problem: the way bacteria resist the action of zinc can be linked to the way they resist conventional antibiotics.

We (and others) have previously shown that addition of high levels of zinc to the diet of piglets selects as well for MRSA (methicillin-resistant Staphylococcus aureus) as tetracycline, the most commonly used antibiotic for prevention of post-weaning diarrhea. If zinc selects for MRSA but not other resistant bugs, while tetracycline selects for a broader range of resistance, zinc use might still be a concern, but it would be a better option than tetracycline. However, that’s not the case and a recent paper in PLOS ONE (Ciesinski et al 2018) provides more information on the impact on other important resistant bacteria.

In that study, they took a typical approach of feeding groups of pigs either low levels (dietary requirements) or high levels (antibacterial levels) of zinc, and they investigated what happens with E. coli. They found significantly higher levels of multi drug resistant E. coli in association with feeding high levels of zinc: 5.8-14% in the control group compared to 29-30% in the high level zinc group. This appeared to be because the resistant strains persisted better than susceptible strains, as numbers of E. coli didn’t increase, but the proportion of resistant strains did.

Does this mean we shouldn’t be feeding high levels of zinc to piglet?

  • I don’t know. Prevention of disease is important for various reasons, including piglet welfare, reduced need to use therapeutic antibiotics (which are often more important drug classes than those used for prevention) and the need for economic production of safe food.
  • Whether antibiotics or zinc are better (or less worse) for resistance in piglets and the corresponding human risk is still unclear.
  • Another unanswered question is the impact of high levels of zinc in manure, since that ultimately makes its way into the ecosystem (just like some antibiotic residues).

However, it provides more evidence that ‘common sense isn’t evidence’ when it comes to antimicrobial resistance. We can’t assume things will have positive or negative aspects because ‘it makes sense’. We need proper research to figure out the best ways to optimize and improve antimicrobial use, minimizing resistance while maximizing the care of people and animals.
That’s antimicrobial stewardship.

Yet another reason not to feed raw chicken

Posted in Dogs, Other diseases

As if another reason was needed, a recent study from Australia (Martinez-Anton et al. 2018 J Vet Internal Med) found a strong association between dogs that consume raw chicken meat and a serious neurological condition known as acute polyradiculoneuritis (APN).  APN is comparable to Guillain-Barré syndrome (GBS) in humans.  The main objective of the study was to look at the association between APN and Campylobacter spp. infection, but knowing that this bacterium is commonly found in raw chicken, they also looked at consumption of raw chicken as a risk factor.  Owners of dogs with APN were 71 times more likely to report feeding raw chicken to their dogs compared to controls.  Of the 27 dogs in the study with APN, 96% (all but 1) were fed raw chicken, compared to 26% of control dogs.

And of course, anytime we’re talking about feeding a raw diet to a dog, we also need to consider the risk to the people who handle the food as well.  According to the CDC, about 1 in every 1,000 reported Campylobacter illnesses in people leads to GBS, and as many as 40% of GBS cases in the United States are thought to be triggered by Campylobacter infection.

Just one more reason to avoid feeding raw chicken to pets, and some extra motivation to pay close attention to safe food handling practices at home.

Canine flu outbreak update: US

Posted in Dogs

While we have hopefully been able to contain our two recent H3N2 canine influenza clusters in Canada (more on that later), this virus continues to spread in some parts of the US, particularly Northern California and Nevada.

  • Since the last update from IDEXX Laboratories on February 2nd, they have identified another 164 cases in the US.
  • Big increases have been identified in Nevada, which went from 7 to 85 cases in 10 days.
  • California cases increased from 243 to 328.
  • The increases come from new cases in the core outbreak areas, as well as extension of the range. Concerningly, this includes identification of the first positive case in Los Angeles (a city with a lot of dogs).

The diagnosed cases also probably just represent the tip of the iceberg, since most dogs with respiratory disease don’t get tested. So, while the true scope of the problem is hard to define, it’s clear that it’s still spreading.

The images below, courtesy of IDEXX, provide a nice update.


Salmonella in kids linked to raw pet food

Posted in Dogs, Salmonella

When we have discussions about the risks of feeding raw meat to dogs and cats, a frequent refrain is “where are the published reports of people getting sick?” While we know some illnesses occur, they tend not to get investigated to the level that they are published, which is problematic when trying to demonstrate the risks. Often the cases aren’t published because of failure to follow up with food testing, disjointed testing of the food and samples from affected people, or issues coordinating the animal, food and human information (given various barriers, including privacy issues).

However, a recent investigation in the US shows yet again that this is a real concern. Salmonella Reading infection was identified in two kids in a household, and the same Salmonella strain was isolated from four samples of pet food, namely Raws for Paws Ground Turkey Food for Pets (which is now under a FDA recall). One child was hospitalized with septicemia (i.e. bloodstream infection, a potentially fatal disease) and osteomyelitis (bone infection).

Deciding whether to feed raw meat to pets requires consideration of the risks.

My approach is that I don’t think it’s a good idea for anyone, but if you’re considering it:

  • A) think about situations where it should never be done, and,
  • B) take measures to reduce the risk.

Check out our raw meat infosheet on the Worms & Germs Resources – Pets page for more information on how to reduce the risks if you’re going to feed raw.

Situations in which raw feeding should not be done include households with people or animals that are more likely to get sick or suffer serious illness, including those with young children, as was the case here.

Image source: CDC Public Health Image Library 21918

WHO rabies vaccination update

Posted in Dogs, Rabies, Vaccination

The World Health Organization has issued new rabies vaccination and post-exposure prophylaxis recommendations. Here are some of the highlights:

Post-exposure prophylaxis

People who have not been previously vaccinated against rabies should receive immunoglobulin (antibody) promptly, followed by a series of rabies vaccines.

Immunoglobulin can be given after vaccination has started, if logistics require that; however, it should not be given more than 7 days after the first vaccination (it won’t do much after that).

Vaccination should not be delayed while sourcing immunoglobulin if it is not immediately accessible.

If immunoglobulin is of limited availability, the following priority list should be considered (in descending order of priority):

  • Patients with multiple bite wounds
  • Patients with deep wounds
  • Patinets with bites to highly innervated parts of the body (e.g. head, neck, hands, genitals)
  • Patients with severe immunodeficiencies (who are less likely to response well to vaccination)

Rabies vaccine can be given intramuscularly or intradermally. The benefit of intradermal vaccination is that a small volume (0.1 mL in 2 sites) is used, which can be an advantage when the supply of rabies vaccine is limited.

Post-exposure vaccination options are:

  • Intradermal vaccination (two sites) on days 0, 3 and 7.
  • Single dose of intramuscular vaccination on each of days 0, 3, 7 and sometime between days 14-28.
  • Two site intramuscular vaccination on day 0, with single site vaccination on just days 7 and 21.

People who have been previously vaccinated (including those that previously received post-exposure prophylaxis) do not receive immunoglobulin. They get one of the following:

  • 1 site intradermal vaccination on days 0 and 3.
  • 4 site intradermal vaccination on day 0 only.
  • 1 site intramuscular vaccination on days 0 and 3.

For any approach, if there’s a delay in the post-exposure prophylaxis schedule, you just continue as soon as possible rather than starting over (i.e. resume vs restart).

Pre-exposure vaccination

Pre-exposure vaccination can be given intramuscularly or intradermally.

Wide-scale vaccination should be considered in remote settings where canine rabies is present and the annual dog bite incidence is >5%.

More emotional support animal ranting

Posted in Birds, Cats, Dogs, Other animals, Reptiles

I’ve written (ok… ranted) about fake service and support animals for years. Beyond frustration with the self-centred and/or “look at me!” aspects, my main concern with the proliferation of fake service animals and questionable emotional support animals is the potential negative impacts on the “real” service and support animals, and the people who actually need (not “want”) them.

There’s been a lot in the news lately about questionable emotional support animals. These include:

Daniel, the support duck (with the viral picture of him walking down an airplane aisle in his bright red booties and leash).

Dexter, the support peacock (who wasn’t as lucky as Daniel and wasn’t allowed on the plane).

Unnamed emotional support turkey (that for some reason was taken to the airport gate in a wheelchair).

I don’t in any way discount the emotional value of animals. I don’t argue that there are people who truly benefit from support animals. Yet, I’m completely against this proliferation of emotional support animals for people who just want to take their pet anywhere or are looking for attention. The proliferation of unusual species bugs me even more, since there’s little reason for these species vs well scrutinized domestic species like dogs, for which we better understand disease risks, behaviour assessment and various preventive and screening measures. Unusual species are often just a “look at me!” plea.

Here’s an excerpt from a website (one of many) that will give you an email “consultation” and letter “certifying” your pet as a service animal:

Anybody can have a dog or a cat. That’s boring! Wouldn’t you prefer to turn heads while you’re walking down the street with something a bit more special? Some rare emotional support animal that only the truly interesting and innovative mavericks of the ESA [emotional support animal] world would ever think to own? Here is our list of seven unusual — but awesome — emotional support animal options.


Included in that list is a bearded dragon. They’re great reptiles as pets for low risk households but are not and should not be support animals. People may get attached to them, but they’re not support animals – they are a high risk Salmonella species. If I was on a plane or in a restaurant next to someone’s support reptile (especially if I was with a young child), I’d lose it.

Balancing the need for true service and support animals with peoples’ self-centred and greedy behaviour is getting increasingly difficult. Ultimately, it’s going to harm the people who truly need these animals.

Canine influenza update: Ontario

Posted in Dogs

Another case of canine influenza has been identified in Windsor-Essex, Ontario. Investigation of the source is underway and measures are in place to try to contain the virus.

As with the other recent cluster of H3N2 canine influenza cases in that region, there is concern about entry of this virus into a naive canine population where there is little to no pre-existing immunity from previous exposure or vaccination.

More information to come.

Image: Colourized transmission electron microscopic (TEM) image of the ultrastructural details of an influenza virus particle. (CDC Public Health Image Library 10073)

US canine flu update

Posted in Dogs

Canine flu has been a hot topic around here, but it’s a bigger deal in the US where the range of the disease is much larger. IDEXX Laboratories has released an update on their canine flu testing results. California has been getting a lot of attention over the past couple of weeks, but extensive flu activity is present in a few other states as well.

Click here for the pdf version of the figures above regarding the H3N2 CIV outbreak in California and other parts of the US.

Petland puppy Campylobacter update

Posted in Dogs, Other diseases

I was talking to someone today about their new puppy, their puppy’s diarrhea and (take a guess) the fact that they developed diarrhea shortly thereafter. Odds are pretty good that puppy and owner both have campylobacteriosis. While this infection isn’t related to the ongoing US multistate Campylobacter outbreak linked to puppies from Petland stores, it’s a good lead-in.

CDCs final update on the Petland puppy outbreak doesn’t provide too much new information, but it shows how extensive and persistent the problem is:

  • The number of reported cases is up to 97. When you consider that a vast majority of cases are probably un-reported, the real number is presumably in the hundreds.
  • Cases have been identified in 17 states.
  • 24% of the 91 people that have been followed have been hospitalized. That’s a pretty impressive number. Fortunately (and not particularly surprisingly for Campy), there have been no reported deaths.
  • 90% of interviewed people reported contact with a puppy from Petland or contact with a person that got sick after contact with a Petland puppy.
  • As reported previously, the strain involved is resistant to many different antibiotics, complicating treatment.

The last reported case began Oct 23. The CDC has closed this investigation, but points out that cases could continue to occur because people may be unaware of the risk of Campylobacter infections from puppies and dogs.  Campylobacter is a common bacterium in young puppies and contact with puppies (beyond the outbreak) is a well recognized risk factor for people getting diarrhea. So, control of this outbreak isn’t going to eliminate the risk of campylobacteriosis from puppies. However, the number of cases linked to this pet chain is remarkable.  Hopefully the source has been controlled at this point.

Campylobacteriosis is in my “don’t eat poop” disease category, and prevention is focused on basic hygiene and fecal handling practices. More information about Campylobacter can be found on the Worms & Germs Resources – Pets page.