dr. hoshizaki: [it is] really a great honorto be here. thank you for having me. iãm really excited to talk about actually oneof my favorite parasites. when they said, ã¬what do you want to do for the conference?ã®i was like, ã¬giardia. thatãs great!ã® so, iãll try to control my enthusiasm. i knowyou guys just had a big lunch, so hopefully i can give you some of my zest. without furtherado ? weãve got a lot to cover ? letãs take a look at giardia: for shelter staff and veterinarians. first of all, when i say the word giardiawhat do you think of? what is the clinical picture? what are you thinking of for humansor animals? audience: diarrhea.
dr. hoshizaki: iãm sorry? audience: diarrhea. diarrhea. dr. hoshizaki: oh, yes. yes. iãm like ã¬diarrhea.absolutely.ã® but, of course, thereãs more to it than just the clinical picture. whatis giardia in a grander scheme? think about that, and iãm going to ask the question againin 20 minutes. hopefully we will have clarified some issues. giardia is a protozoan parasite that livesin the small intestine and you can see here [the] little teardrop shaped protozoa on theslide. as you guys already know, or many of you know, diarrhea is what we think of ? sogastrointestinal disease in dogs, cats and
humans. this is a zoonotic disease, whichaffects humans and other animals. i just googled ã¬giardia outbreak,ã® and look, i got onereally close to here, really recently. itãs an important zoonotic disease that affectshumans and you are going to see it in the news. of course, in the shelter setting, whereweãre thinking more about cats and dogs, unfortunately, it is a very difficult diseaseto diagnose and to treat in that setting. we have two varieties of giardia, which weare going to think about. weãre going to think about the adults. these are the protozoa,which are in the small intestine. they are the ones who are causing disease. one of thereasons why they are my favorite is because i think they look like little smiley faces.i donãt know. iãm not great with all of
the other eggs, but if i see a giardia i knowwhat it is. itãs smiling right back at me. the other form of giardia we think about isthe cyst. these are ã¬eggs,ã® which are in the environment, and these are what are infectingthe other animals in the shelter. coincidentally, i kind of also think they look like littlesmiley faces. i donãt know if anyone else sees that. in order to treat giardia effectively in theshelter, we need to know a little bit about its life cycle. very simplistically, we beginwith a cyst in the environment. itãs going to infect our host, which is our cat. oneway or another, this cat is going to ingest the cyst and become infected. once insidethe cat, we are going to have the cyst mature
into the adult protozoa and itãs going tomake little friends. we going to cause disease and weãre going to keep multiplying and producingmore giardia. at a certain point, weãre going to start producing more cysts. theyãre goingto start reproducing, and theyãre going to go out in the feces, in our diarrhea. so thesecysts are going out, back into the environment, and theyãre going to be able to infect moreanimals. as weãve already mentioned, transmissionis primarily what we call fecal-oral, or poop-to-mouth in laymenãs terms. somehow these animalsare eating things, which are contaminated with feces. this can be through food, throughwater sources, and very importantly, in the environment. i have a picture, there, of somepuppies out in a play yard. they are going
to have cysts in the dirt. itãs going tobe on the wire. itãs going to be on all the food bowls, etcetera, and itãs going to beon the equipment. if weãre moving things between cages that could possibly be contaminated,thatãs another great way to spread your cysts. also shown in this picture very well is [contamination]through fur and grooming. the cysts come out in the diarrhea. theyãre going to stay onthe back ends. if dogs are walking in it, it is going to be on their paws. if the catgoes around grooming itself, it is going to be licking up those cysts and re-infectingitself. as i mentioned, giardia is a potentially zoonoticdisease, so it is important for us to think about ourselves and the staff members. themain species of giardia that weãre talking
about today is giardia duodenalis, and ithas several sub-groups, which are called assemblages. different ones have different zoonotic potentials.some infect humans and some do not. a and b assemblages are the ones which can affectanimals, cats, dogs, wildlife and livestock, etcetera. these are the ones that weãre worriedabout to potentially cause disease in humans. assemblages c and d are specific to dogs,and f is specific to cats. these are ones weãre not so worried about. now the question is, [if] we have an animalwith giardia how do we know if this is going to be a zoonotic issue in our shelter? unfortunately,the answer is [that] we donãt know, because we only can find out what assemblage an animalhas if we do dna testing at the laboratory.
this is something which is expensive and timeconsuming. most shelters are not going to be doing this on a routine basis. itãs justthe reality. so the risk ? and iãve looked at a few paperson the subject. it looks to be [that] maybe half [of] animals are carrying potentiallyzoonotic forms of giardia. whether or not it actually goes on to infect humans is adifferent issue. some studies have shown that there actually may be a lot of animals ? yourpet cats and dogs could be holding a zoonotic form of giardia. going on for a bit more,[regarding] studies in the united states, there are a couple of surveys looking at petcats and dogs and the prevalence or how common the disease is. [they report that it] is aroundfour or five percent.
fast forwarding to shelters, we can see thatthe prevalence is a lot greater. same thing for kennels and catteries. animals housedin group conditions with issues of hygiene and sanitation, obviously weãre going tohave more disease. but of course, itãs going to vary where your shelter is. what are theages of the animals that are infected? what are your protocols and your husbandry proceduresfor your shelter? that is really going to impact how much disease you have. a couple of quick risk factors for giardiainfection. we most commonly see it in young animals. these are animals under one yearof age. in adults, itãs less common, because we think they get an acquired immunity. theyalready have antibodies and theyãre able
to fight off the giardia. so, weãre reallylooking at young animals for this disease. the presence of other diseases. quite oftenin our shelters we see young animals that have a variety of parasites ? you know, roundworms,other protozoa, etcetera ? and these are going to make your clinical disease much worse.itãs not just the giardia which is causing them to have diarrhea. very importantly with giardia [it] is a seasonalpattern. when itãs wet, rainy and cold [in] autumn and winter, that is when weãre goingto see more disease, because the cysts live happily in puddles and in wet environments.they are not going to be killed as easily. clinical signs. you guys already nailed iton the head. weãre thinking about diarrhea,
inappetence or anorexia, weight loss or akitten thatãs not growing so well. these are all classic, clinical signs. we also cansee vomiting, but it is less common. what i need to draw your attention to, which isvery important, is [that] many animals with giardia have no clinical signs. these animalsare asymptomatic. they are infected and they are potentially shedding and contaminatingthe environment, but we do not know just by looking at them. now that we know a little bit about giardia,we need to go on the man hunt. how are we going to find it? the classic way for lookingfor giardia is through a microscope of fecal samples. we need to do our examination witha special zinc sulfate flotation, which is
not the normal way we do flotations if anyof you have been involved in doing a little microscopy in your shelter. itãs not thenormal way we look for parasite eggs. itãs a special solution. the cysts are very small. they can look likeyeast and are very delicate, which is why we need the special solution. otherwise, wemight not be able to find them. basically, we need experienced personnel to look at theseslides. not just anyone can [take] a fecal sample to the microscope and find giardia. the other really important point i need tolabor is that even if we go and get the sample from the animal thatãs sick, they may nothave cysts in the feces at that particular
moment. we need to go and get another sampleand another sample. we recommend at least three samples over the course of several days,so weãre screening multiple times to increase our sensitivity and likelihood that we willfind one of those cysts. hereãs actually quite an unusual slide, nowthat iãm thinking about it ? the trophozoite, which is a fancy word for adult giardia, andone of the cysts. usually, we are just looking for the cysts on the slide, because the adultsdonãt survive well in the environment. itãs really the cysts that weãre concerned with.that just gives you an idea what they look like. if youãve ever looked for other parasitesunder the microscope, you might recognize some of these eggs. we have the roundworm,the whipworm and the hookworm, [which is]
massive compared to the size of a giardiacyst. if you donãt know what giardia looks like, if youãre not looking for it, you cansee how easy it would be to miss [it] on a routine examination. what other options do we have for diagnosis,since clearly, looking [for it] on the microscope is maybe not the best solution for everyone?luckily, we have the magic snap test and i am sure most of your shelters have used snaptests. it is just like all of the other snap tests we use. it is looking for a specialprotein in the feces thatãs going to be present whether or not the animal is shedding cysts.thatãs really great for us. itãs much more sensitive. we are more likely to get a goodresult using snap tests.
there are other lab tests available. thereare amino assays and the pcrs, but for most shelters what weãre really going to be dealingwith is the microscope and the snap test. remember, in the back of your mind, thereare other options. now we diagnosed our animal with giardia.now what are we going to do? weãre going to treat it. the first question we have toask is ã¬who are we treating?ã® if we have an animal, which is clinically ill, we snapthem. we get a positive. yes, weãre going to treat them. what if we have done a fecaland we found giardia, but theyãre not sick? are we still going to treat them? if you havefive kittens in a cage together and one of them comes up positive with giardia are wegoing to treat all the kittens in that cage?
i see some nodding in the back. very good,alright. what i really want to labor is that our treatment is aimed to resolve the diarrhea.we want the animal clinically healthy so we can get them out to adoption or just out ofthe shelter. we donãt necessarily want to make them snap negative. weãre not necessarilygoing to get rid of the giardia, and thatãs something really important to keep in mind. [my] favorite choice of drug at the momentis fenbendazole, or you may know it panacurã†, which works in cats and dogs. easy. give itonce a day for five days. pretty good results to resolve clinical signs, lessen the diarrheaand get rid of the giardia. another option, which some people have beenexperimenting with is febantel combination
products, also known as drontalㆠplus, whichis licensed in dogs. some people have been experimenting with its use in cats, and therehas been some success. another popular drug that people use for giardiais metronidazole. itãs gone out of fashion recently because high doses can cause neurologicalsigns, can cause birth defects and shouldnãt be given to nursing mothers. of course, giardiacan become resistant to metronidazole, so you can see how that would be a problem. [with]resistant giardia, people keep increasing the dose, and suddenly you have all theseadverse effects. now that weãve done our drug protocol, weneed to focus on the rest of the animals and the rest of the shelter. unfortunately, thismeans bathing our cats. we need to prevent
re-infection. all the cysts that are stuckin the fur, we need to get them out. weãve got to wash our cats and dogs. we have toclip them if theyãre going to be matted or getting really dirty in their hind end. weneed to clean the environment, so whatever cage theyãre in we have to make sure thatwe are going to move them to a clean environment. we are going to move them out of the spacewhere they were infected with giardia, where all the cysts are in the environment. weãregoing to move them into a clean cage, so that theyãre not going to be licking the wallsand getting more cysts. weãre going to be promptly removing the feces in that new, cleanenvironment, because even though weãre treating them they still could be shedding cysts. ifthey step in it or contaminate their food,
it is just going to make the process harder.theyãre going to be re-infecting themselves. so, now we need to deal with our originalcage, which has been contaminated by all these feces and the cysts. the first thing weãregoing to do is weãre going to scrub. weãre going to physically get in there, manuallyremove as many cysts as we can with just soap and hot water and get rid of what we can.weãre going to remove our soap. weãre going to rinse it out and let it dry. the reasonwhy weãre doing these first two steps ? getting rid of all of the gunk and newspaper and whateveris left in the cage and drying it ? is so that our disinfectant is more effective. thedisinfectant of choice that weãre using is a quaternary ammonia compound, or quats. thereare some brands you might be familiar with.
these have been proven to be quite effectiveat getting rid of the cysts, so the cysts that we havenãt scrubbed out should be killedby the quats. we want to make sure we have a good contacttime. we want to make sure we leave that quats on there for at least ten minutes. check thelabel [of] whatever product youãre using, because we really want to make sure weãrekilling all those cysts that are residual, still in the cage. weãre going to wipe it clean and then finally,most importantly, weãre going to dry it. cysts, like i said, they live in the winter.they live in the wet. they live in the damp. we need to get it dry, so we can desiccatethose cysts, make them so theyãre no longer
infective. they can survive for weeks or monthsin a damp environment, so we really need to keep that in consideration when weãre cleaningour cages. you canãt just hose it down and shove new animals in. this is a picture from a shelter in new zealand,where i did a couple of rotations where they had chronic, chronic giardia and other parasiteproblems. you can see where it says, ã¬animal housed.ã® is it indoor or outdoor? audience: looks like outdoors. dr. hoshizaki: outdoor and iãll tell you,new zealand has about as much rainfall as seattle. itãs always wet, so this dog isin a place that theyãre never going to be
able to clean this kennel, right? itãs goingto be always contaminated with these cysts, no matter how hard they try, just becauseof the nature of wood and being outdoors. so, now weãve treated the individual animal.we need to think about everyone else who could be affected by the giardia. what we need todo is prevent the spread throughout the shelter to the other animals. weãre going to placeappropriate signage. weãre going to put a big, old sign on the cage and say, ã¬i havegiardia. wear gloves. wash your hands.ã® ideally, limit handling to those who know about giardia,know the zoonotic potential and know how to handle it, so theyãre not spreading it throughoutthe shelter. not every volunteer should be cuddling the giardia puppies.
we need to have appropriate cleaning protocolsand this applies, of course, across all the diseases weãre dealing with. if we have goodprotocols weãre going to be eliminating all the different diseases, not just giardia.by picking up the feces and keeping it clean weãre preventing re-infection of all thediseases, not just giardia. we are going to allow the cages to dry before we add animalsagain. weãre going to keep the animals separate.iãm not saying you have to isolate them. this isnãt like upper respiratory, wherethey need to go into a separate room necessarily, but we donãt want to mix them. if the puppywith giardia goes out into the play yard and then you have all your other dogs come outinto the play yard, whatãs that going to
do? thatãs not going to be helpful for yourtreatment regime, because theyãre going to be contaminating that environment. theyãregoing to be contaminating the community cat room or the hallway where everybody walks.so, you need to be conscious of where youãre taking these animals and what other animalshave access to that space. of course, we donãt want to be mixing animals, especially litters.you donãt want to be putting sick animals in with the non-sick ones. itãs common sense,right? because young animals are more easily, orat least more commonly, infected ? we see them as clinical disease in the young animals? we want to keep them in easily cleaned cages. we donãt want to put them into the nice,posh cat room with all the furniture. we want
to keep them somewhere that we can clean incase they do get sick. i already touched on this. what are you goingto do when one of those cats starts having diarrhea, we snap test it and it comes backpositive for giardia? weãre going to get rid of all the furniture that we canãt cleanand all [of] the carpeting. weãre going to get rid of all [of] those toys and all [of]the blankets. it looks like in this picture that they have cardboard little hidey-holes.[that is] great, because we can throw those away? the cardboard hidey-holes and cardboardlitterboxes. these are things we can get rid of. itãs not a great cost. we are going to be treating that one particularanimal and weãre probably going to be treating
all the other animals in that environment,because even though they donãt have diarrhea, they have been exposed. chances are they couldbe asymptomatic, but still infected. of course, we are going to be putting up signson this door. this looks like probably an adoption area, so we want to make sure thateveryone knows whatãs going on in this room and weãre not just tracking giardia in andout. what about this? there are a few interestingthings in this picture. thereãs a pool, a very nice swimming pool, for the dogs. thereãsa wooden pagoda, and thereãs gravel. gravel is not as bad as dirt and grass, but iãmsure you can imagine if a dog with giardia defecates in that yard that gravel is contaminated.how are we going to contain that? same thing
with the pool and with the wooden pagoda.how are we going to contain that? we might end up having to resurface our play yard.that is not something anyone wants to do. audience: is there any type of treatment whereyou can treat the yard? dr. hoshizaki: thatãs a very good question,and iãm hesitant to give a direct answer to that, because i guess it depends. if theanimal goes to the bathroom right away, and weãre able to pick it up immediately, isall the soil around it infected? or has it been chronically infected with giardia andall the dogs have been kicking up the dirt and itãs that we have layers and layers ofcysts in the soil? iãm not aware of any recommended protocol really for that, unfortunately. insome situations you just canãt get around
it. resolution. so we come back two weeks later,after weãve been treating our animal, and weãre going to do a snap test again or lookunder the microscope again. if the animal is still sick, weãre going to still treat.no brainer. but, we need to think why did our treatment fail? why did the animal potentiallyre-infect itself? did we not sufficiently clean it? did we not keep their environmentclean? did we put them in an environment, which has cysts still in it? we need to keepthese things in mind, because re-infection is more common than treatment failure. wemay want to consider a different drug protocol if we think we didnãt use the correct dosageor the right amount of time for the drug to
take effect. we also need to look for other causes of diarrhea.like i said, giardia might just be one part of the problem. the animal might have someother issue, or other parasite, which is causing the disease and we need to make sure we haveruled those out as well. now we have to think about adoption. if wehave an animal [that] we have treated for giardia, it is healthy, but itãs still snappositive, what do we do? we need to weigh the pros and cons and how weãre going totackle this adoption. of course, always in the back of the mind weãre thinking, ã¬weare adopting out an animal that has a potentially zoonotic disease and what does this mean forour adopters?ã®
we need to remember that immunocompromisedhumans are at risk, so people with certain diseases and children. giardia can be verylife threatening for them, so we need to consider what kind of home weãre placing this animalin. many shelters have chosen to do a waiver. of course, client communication and educationis very important. we are going to have someone sit down with them, and explain to them thatthey are adopting an animal with giardia and this is what it means. we can have them signa waiver to help negate some liability on the shelterãs behalf, but as you probablycan figure out, thereãs no great way of completely reducing the risk. as another side, if youãre adopting out acat with giardia and youãre adopting it out
to the nice old lady who has six other cats,what does that mean to her whole household? are there going to be repercussions down theroad ? that youãre going to feel quite bad about if she comes up with a bunch of sickcats? i asked the question, ã¬what is giardia?ã®now, in your mind, iãm hoping a few more light bulbs are going off. itãs not justdiarrhea, right? it is a common disease. dogs, cats, humans and other animals, we need tobe aware, have giardia. itãs a challenge to control depending on what kind of roomsyour animals are housed in, what kind of cages and what kind of sanitation protocols youhave. control really depends on how youãre taking care of your cleaning in that shelter.
always remember, animals that are healthycould still have giardia. animals that you treat could still have giardia. we need toconsider the risks, and decide what is best in our shelter situation of how weãre goingto deal with this problem. if you would like some light reading, i canoffer some excellent references. thatãs the end. i would like to thank maddieãs fundã†,the aspca and cornell university for having this talk and for having me. iãd like toit open up to any questions you guys may have.
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