Worms & Germs Blog

Canine Giardia in a person

Posted in Dogs

dog-walkersAs someone who has had Giardia (including one episode that put me in the hospital when I was in vet school), I know how bad it can be. However, my concern about the human health risks from dogs with Giardia has been pretty low. Giardia comes in several different “assemblages” (types) and these types like different hosts. Types C and D are considered canine-specific (i.e. they only infect dogs), and its been assumed that dogs with these pose little to no risk to people.

A recent report from Slovakia probably doesn’t change that dramatically, but it does raise some questions.

The paper in question is a case report describing human infection with Assemblage C Giardia in a person (Strkolcova et al Acta Parasitol 2015). The woman had chronic diarrhea and some other signs of illness, and Giardia was seen microscopically in her stool. Subsequent testing then identified it as Assemblage C.

I’d avoid reading too much into a single case report. It’s possible that she was shedding this strain of Giardia but something else was causing her illness, or that she had some unusual risk factor, or that this wasn’t really Assemblage C, or that this is a one-in-a-million situation. However, it means we should pay attention and realize that (as is common) things are not always as definitive as we’d like to think.

Medical tourism for animal cell injections….bad idea

Posted in Other diseases

Sheep x2Ok, call me risk averse, but traveling to another country to have someone inject me with cells from organs or fetuses of animals isn’t high on my to-do list. I guess that’s a good thing, given the recent article in Morbidity and Mortality Weekly Report describing Q-fever in people from New York who traveled to Germany for such a treatment.

Q-fever is a sometimes nasty and highly infectious disease caused by Coxiella burnetii, a bacterium that’s mainly associated with pregnant sheep and goats. The affected individuals in this report traveled to Germany for “live cell therapy,” which is advertised as a treatment of various disorders and (wisely) unavailable in the US. (However, I have little doubt that people are doing it, particularly in the sports medicine world.)

All affected individuals went to the same German physician and were injected with fetal sheep cells. The investigation started after Q fever was diagnosed in a Canadian woman who also saw the German physician for the same treatment just two days before the group of New Yorkers were there.  that had  The Public Health Agency of Canada notified German authorities, who happened to be investigating a Q-fever outbreak in Germany associated with “inhalation exposure to a sheep flock that was used for production of fetal sheep cells injection by the German physician” at the time. The authorities notified the physician, and the physician notified his patients (4 months after the treatment was done). Three of the Americans had already sought medical care for signs of Q-fever (although it’s not clear whether Q-fever had been suspected or diagnosed) while 2 others were sick but had not yet sought medical care. Three of the five still had symptoms such as fatigue, chills, sweats and difficulty sleeping 9-10 months after exposure, showing how this disease can be a long-lasting problem.

Common sense goes a long way, so does the “above all, do no harm” concept. Too bad those are often ignored.

Antibiotic use in an antimicrobial-resistant world

Posted in Cats, Dogs, Horses, Other animals

Syringe and needlePrudent antibiotic use. Antimicrobial stewardship. Whatever you want to call it, it’s an important subject.

I spend a lot of time working in this area, and figuring out how to effect real change is the challenge. That means getting to prescribers. If I’m at a conference and have a talk titled “Antimicrobial stewardship” (or something along those lines), the audience will likely consist of the moderator, some people from the pharma industry, some regulatory personnel and the guy that ended up in the wrong room. It might be a great talk and discussion, but it’s unlikely to do anything with that crowd.

In contrast, if I’m at the same conference and do a talk about “Treatment of urinary tract infections in dogs and cats”, the room’s probably going to be packed, and hopefully I can get some points across that improve antibiotic use AND patient care. The “and” is critical, because taking care of our patients (and their owners) is the most obvious goal for a practicing vet.

So, improving antibiotic use while maintaining some clinical perspective and fostering good patient care is the key, at least for me.

Along those lines, Clinician’s Brief (of which I’m Editor-in-Chief) recently adopted an antimicrobial stewardship policy. As a leading provider of veterinary continuing education, case management recommendations in Clinician’s Brief get a lot of mileage, and we’ve tried to optimize patient care and antimicrobial stewardship.

Here’s the highlight:

Authors who provide antimicrobial treatment recommendations must consider the potential impact of veterinary drug use on public health. In particular, authors should avoid recommending extralabel use of fluoroquinolones and extended-spectrum b-lactam antimicrobials (eg, third- or fourth-generation cephalosporins) or recommending drugs such as carbapenems, glycopeptides, and oxazolidinones used for treatment of multidrug-resistant pathogens in humans. If use of any of these is recommended, there must be specific mention of the relevant issues, and evidence supporting the recommendation must be provided.

Is it perfect? No.

Is it useful? Hopefully.

It means that authors have to think about their antibiotic recommendations, which is good because sometimes recommendations just get written out by rote, or passed down from earlier (untested) recommendations, or they’re made without much thought about resistance issues. This makes authors and editorial staff think about which way the balance of patient care and antibiotic stewardship tips.

Baby steps for a big problem, but if we’re stepping in the right direction, that’s good.

New Ontario rabies website

Posted in Cats, Dogs, Horses, Other animals, Rabies, Vaccination

Fox yawningThe Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) has launched its new (and long-awaited) rabies website.  The site includes a section for the public which is an ideal resource for clients, and a section for veterinarians with detailed information about reporting, risk assessment, sample submission and testing, and post-exposure management (for companion animals and livestock).  Veterinary staff in particular are encouraged to review the page and bookmark it for easy reference.

In addition to the website, OMAFRA has also created a 35-minute Rabies Response Training Module and online evaluation for private veterinarians.  The training will help to streamline risk assessments and sample submission for domestic animal exposures.  More details are available on the new website.

Bovine leukemia virus and breast cancer

Posted in Other animals, Other diseases

Holstein cowA new study from the University of California, Berkeley, has shown a potential link between bovine leukemia virus (BLV) and breast cancer in women (Buehring et al. 2015).

The short version is the study analyzed breast tissue from 239 women, and found evidence of BLV exposure in 59% of the samples from women with breast cancer, compared to only 29% of samples from women without a history of breast cancer.  As the authors point out, this is an important finding but only the first step – for a start, they “still need to confirm that the infection with the virus happened before, not after, breast cancer developed, and if so, how.

There are various examples of cancer-causing viruses in the human and animal worlds. For example, hepatitis B virus in people can cause liver cancer, and human papillomavirus can cause cervical cancer.  In sheep and goats, there is a virus called nasal adenocarcinoma viurs which causes “contagious” nasal tumors.  However, perhaps partly because viruses tend to be more species-specific than bacteria, there are no known zoonotic viruses that have been linked to cancer in humans – yet.

Bovine leukemia virus is a well known retrovirus that naturally infects cattle.  Most cattle that become infected do not show any signs of disease, but less than 5% will eventually develop cancer (lymphosarcoma).  The virus is transmitted between cattle primarily by blood contamination (e.g. reusing needles on multiple cattle, contaminated ear tagging equipment, blood on rectal sleeves).  A number of studies have been done in the past to evaluate if BLV is a risk to people, but none produced any conclusive evidence that the virus is hazardous to humans.  Until a recent paper published in 2014, it was thought that BLV virus could not be transmitted to people at all. Several European countries have managed to successfully eradicate the disease, but test-and-slaughter programs are often not practical when infection is common (estimated prevalence in US dairy cattle is 44%, and 10% in US beef cattle).  Instead, the emphasis is placed on preventing transmission within the herd, and infected cattle are then gradually eliminated through normal culling for other reasons.

If more evidence of a link between BLV and disease in humans is found, the cattle industry will then have considerably more motivation to eliminate this virus from their herds (which would benefit the cows as well of course).  However, as the authors of the study point out in the news release, “our results do not prove that the virus causes cancer.”  While we await further research, consider it yet another good reason to ensure meat is always cooked properly and milk is pasteurized before consumption – viruses like BLV and other zoonotic bacteria can’t take the heat!

Rabies socks

Posted in Dogs, Rabies, Vaccination

Rabies socksWhen I  saw “rabies socks“, my first thought was “someone’s going to be cursing their autocorrect“.

Apparently not.

The Ontario Association of Veterinary Technicians (OAVT) Rabies Response Program (RRP) World Rabies Day socks (they might want to come up with a shorter name) are on sale now, with a portion of the proceeds going to the Northern Cree Dogs Project.  The campaign runs until September 27, 2015 (the day before World Rabies Day, which occurs annually on September 28)

If you would like to order some socks and support the campaign, click here.


CPHAZ symposium presentations online

Posted in MRSA/MRSP, Parasites, Salmonella, Toxoplasmosis

CPHAZ_bw_logoPresentations from the 2015 Centre for Public Health and Zoonoses (CPHAZ) Symposium are now on YouTube on the Worms & Germs Blog channel.

There is a wide range of talks, including topics such as West Nile virus, Lyme disease, salmonellosis, MRSA, Toxoplasma and various other zoonotic diseases.

Resistant Staph in Animals Conference

Posted in Cats, Dogs, Horses, MRSA/MRSP, Other animals

I realize this is outside of the scope of most readers (so let me apologize in advance for some wasted electrons), but here’s a quick announcement of the 4th ASM/ESCMID Conference on methicillin-resistant staphylococci in animals; animals and human health implications. (Yes, the name’s a bit long and drawn out, and I probably take the blame for it since I think I came up with it originally, but at least it’s descriptive).

This is a nice interdisciplinary meeting for people from the veterinary, public health, human  infectious disease and microbiology fields, and this time it’s being held in Chicago in November. Anyone interested in the meeting can find out more here.

1 copy

Equine infectious anemia in Canada

Posted in Horses

horse-with-bridleA recent cluster of equine infectious anemia (EIA) cases in Saskatchewan highlights the personal side of EIA control. EIA is a serious insect-borne viral disease of horses that can cause illness ranging from mild to fatal. Some horses recover uneventfully but are then potential sources of the virus for others, and disease can build up slowly and silently in the horse population. Because the disease can be so severe and survivors become life-long carriers, there are EIA control programs (and importation rules) in many countries, including Canada. Here, horses that test positive for the virus must be euthanized, or housed in strict fly-proof isolation that is utterly impractical in most cases. So, a positive test almost always means euthanasia, even if the horse appears outwardly healthy. Some horses are diagnosed when they get sick, and others are identified during routine testing (many people still refer to this as the “Coggins test”, but the test used for initial testing is now different).

A recent cluster of EIA infections was detected on a farm in Saskatchewan. In July, one horse on the farm was identified as being infected. This lead to an investigation, because EIA is a federally reportable disease.  Ultimately 9 other positive horses were euthanized on Aug 19. It was suspected that more euthanasias would follow,  because more test results were pending.

While there is some (rather token) compensation for animals that must be euthanized due to EIA infection, the owner’s comments are similar to those from other outbreaks:

“Some of these horses, I’ve got a lot of money invested in them, and some of them maybe aren’t worth much to people,” he said. “But to ourselves, they’re worth a lot of money because they’re trustworthy. They’ve done us very well. How do you put a price tag on that?”

 “(The horse) can act normal, be normal, do normal everyday things,”[the rancher] said. “You can ride them and everything like that, but until you draw blood from them you’ll never know (they’re infected).”

The financial and emotional impact of euthanasia of positive horses can be substantial. This can lead to arguments both for control (e.g. let’s control the disease so this doesn’t happen again) and against control (e.g. let’s stop killing horses that aren’t necessarily sick).

EIA control is a timely topic in Canada, given potential changes coming to the national control program. One concern is whether the program is effective or if it mainly just satisfies international horse movement concerns.

Reasons for having a control program:

  • EIA is a nasty disease that can spread silently in the horse population.
  • Testing is a key part of control and measures to deal with positive animals (unfortunate as they are) are critical to containing or eliminating the disease
  • Control of EIA is important for international horse movement, as increased barriers could be put in place if this disease is not considered adequately controlled within Canada.

Reasons against having a control program:

  • It’s expensive
  • Testing is unbalanced. Some horses (e.g. competition horses) are tested regularly while others are almost never tested. The horses that are regularly tested are typically the low risk horses, while the ones at highest risk of infection are not tested.
  • The implications of a positive test can lead people to avoid testing unless it’s absolutely required.
  • There are questions about why the government should pay for this program, since it’s not a disease that affects people or food animals.

In the outbreak reported above, the owner said:

“I think (the government) should start implementing it, and make it a mandatory test right across the board. I think that’s the only way you’re ever going to get a little bit of control on this disease, otherwise it’s going to run rampant.”

You’ll find lots of other people in that area that will say “I think the government should stay away. They’re wasting a lot of our money and killing our horses, even the ones that aren’t sick.” (I’m making up that quote but it’s pretty much verbatim from conversations I’ve had.)  Not a good way to contain a disease, but you can see why comments like that are made.

There are a lot of knee-jerk reactions to discussions of EIA control, but once you get thinking about the issues, it becomes very hazy. Good arguments can be made for many different options, including keeping the program as it is, or modifying the program to reflect the fact that EIA is well controlled in some regions but poorly controlled in others. Ultimately, the equine industry will have to take a leading role in determining what is required from an EIA program in Canada, the implications of any changes, and how to sustain any funding for the program since federal efforts may not be maintained at the current level in the future.

There will be a lot more debate, only some of which will be based on science.  It will be interesting to see where this ends.

An infosheet (short and long version) on equine infectious anemia is available on the Worms & Germs Resources – Horses page.