Duodenum Giardia is a protozoa parasite that usually infects a variety of mammals, including cats, dogs and humans. Giardia is a species complex that includes at least 8 genetically distinct but morphologically identical sets (named A to H), with cats most frequently infected with set F. Giardia may be zoonotic because animals sometimes hide collections A and B, which more often infect humans, but no reports of Giardia collections from cats (F) or dogs (C and D) adapted hosts in the United States. Giardia infection in cats can be subclinical, but the most common clinical symptom is diarrhea. Historically, Giardia infection was diagnosed by microscopy of feces, but immunologic tests for detecting antigen in feces have now been widely used as a bedside test. However, even with improved diagnostic tools, Giardia infection in cats remains a difficult problem, as treatment is not always 100% effective, reinfection is common, and concerns about the possibility of zoonotic diseases remain.
spread and life cycle
giardia spreads through feces-oral pathway. The cysts fall off in the feces and are immediately contagious after being excreted. Cysts can be directly ingested from infected hosts, contaminated food or water, or contaminated contaminants in the environment.
Each cyst contains 2 trophoblasts, which appear when the cyst reaches the small intestine (decapsulation). Trophoblasts are the pathogenic stage of parasites. They reproduce by longitudinal dichotomy , either free in the cavity, or adhere to the mucosa using abdominal suction cups, resulting in malabsorption and fatty diarrhea. The trophoblasts undergo encapsulation as they move towards the colon, forming new cysts. Environmentally resistant cysts fall out intermittently in the feces. Trophoblasts can also be occasionally transmitted through diarrhea, but they are non-infectious and do not persist in the environment.
Cats have a jaundice incubation period of 5 to 16 days, and cyst shedding is usually periodic. It should be noted that pets, especially cats, may ingest the cysts from the contaminated fur when combing their hair.
Clinical symptoms
Acute or Chronic diarrhea is the most common clinical symptoms of infection, which can lead to weight loss and the infected kittens cannot gain weight. In clinically infected cats, the feces are usually soft and pale in color, and also contain increased neutral fat and are described as more foul than normal.
Diagnosis
In order to determine the best test (microscopy, immunology, molecule) to detect Giardia infection, a large number of diagnostic comparison studies have been conducted, but there is only one common result-no single test can detect all infections. The Companion Animal Parasites Committee (CAPC) recommends that direct smear and centrifugal fecal floating should be performed when detecting symptomatic cats (and dogs) infection in clinically, combined with veterinary-approved sensitive and specific patient-side antigen testing. This combination of diagnostic tests maximizes the chances of detecting giardia.
is difficult to diagnose Giardia by microscopy alone for many reasons: the cysts are small (10 to 12μm long; (Figure 1), intermittent shed, transparent, fragile in flotation solution. In conventional clinical practice, antigen detection for humans is not used in cats or dogs, as they are not optimized or approved for clinical use in animals.
Figure 1. Duodenal giardia cysts (arrows) are recovered by centrifugation of fecal flotation with zinc sulfate; hookworm eggs (asterisk).
Reference laboratories and some university laboratories can perform molecular tests to detect giardia stools in feces DNA, but is usually more expensive than performing or sending tests for fecal floating or using patient-side antigen detection. Polymerase chain reaction (PCR) assays available in commercial laboratories usually do not include genotyping or sequencing to determine the collection of giardia.
It is particularly important to note that, according to the recommendations of CAPC, patient-side antigen detection is only used in symptomatic patients (intermittent or persistent diarrhea). If clinical symptoms are not eliminated, subsequent tests for centrifugal fecal floating should be performed within 24 to 48 hours after treatment, rather than antigen detection.The timing of subsequent testing is crucial because the cat's Giardia incubation period is as short as 5 days and must be tested before this time has passed. Usually, suspected drug resistance or treatment failure is actually reinfection, and if subsequent testing is performed after 5 days or more, the source of infection cannot be determined.
Popularity
Giadi genus is distributed worldwide and can be found in every region of the United States. The prevalence of the genus Giardia infection in cats varies by population (e.g., individual pets, group pets, breeding groups, shelter animals, stray animals), geographical location, and the diagnostic method used.
For example, in a survey of patient-side antigen tests in symptomatic cats across the United States, 10.8% (512/4977) of cats tested positive for Giardia. Another survey found that 31% (36/117) of the cats tested from the international cathouse were infected with the Giardia flagellum. In 2020, the national prevalence of giardia in American cats was 4% (Figure 2). These data were derived from more than 1.8 million cat feces samples by CAPC, but since they did not include cats or stray cats who did not visit the veterinary and not all veterinary clinics use reference labs, 4% can be considered as the lowest baseline prevalence of essentially asymptomatic individuals.
Figure 2. Prevalence of giardia sapilla in the United States in 2020. Based on data from the Companion Animal Parasite Committee, fecal test results from AntechDiagnostics and IDEXX laboratories were compiled. Data are derived from the Companion Animal Parasite Committee Parasite Epidemic Map.
Treatment of
In the United States, there is no approved drug for the treatment of cat Giardia. However, it is safe to treat infection in cats with feline (metabolismol after oral administration) and febendazole and metronidazole and have varying degrees of efficacy. Metronidazole (25mg/kg) is taken orally twice a day for 5-7 days and can successfully remove the Giardia infection in experimentally infected adult cats. Fibantel (37.8 mg/kg) is a combination product containing both pyrantol (7.56 mg/kg) and pyraquantel (7.56 mg/kg). After 5 days of administration, the infection in the experimentally infected kittens was successfully cleared.
CAPC recommends treating Giardia infection in cats with fenbendazole (50mg/kg) for 5 consecutive days or metronidazole (25mg/kg) twice a day for 5 consecutive days. However, there are some safety issues with using metronidazole in cats, and cats with pregnant or breastfeeding and cats with epilepsy or liver disease should avoid metronidazole.
A preliminary study of secnidazole (30mg/kg) in 18 experimental cats found that it was effective in eliminating cyst shedding, but the follow-up period lasted only 8 days. In addition, 11 of the 18 cats experienced excessive saliva secretion after administration, and 4 of the 18 cats suffered from loss of appetite for 2 days. However, because the number of cats in each trial was small and there was no comparison with metronidazole or fenbendazole, there were some limitations in the study.
Prevention
It is difficult to completely eliminate the giardia worms because once the cyst falls off, it will be infected immediately and it is very likely to be infected again. Therefore, preventing feces from contaminating the environment is crucial to preventing reinfection. It is recommended to take a bath to remove fecal debris containing cysts from the fur. It is also recommended to disinfect cathouses or homes, including cat bags, litter boxes and cat nests; quaternary ammonium salt products, boiling water and chlorine are considered effective for the cyst.
The impact of zoonotic
The focus of concern about the potential zoonotic diseases of Giardia is the collection of infections of humans and animals A and B. Collection A has different zoonotic potentials and is further divided into AI subtypes through AIV; humans appear to be infected with AI and AII, and animals are infected with AII, AIII and AIV. Therefore, ensemble AI seems to have the widest range of hosts.
Giardia colonies that infect cats and dogs are usually host-adaptive and have not been reported in the United States to infect humans in pets. These host adaptive populations are more common than any potential zoonotic population. However, it is reported that groups A and B infected cats, and it is these cases that pose the greatest zoonotic risk to people. A survey of Virginia cats found that 22% (12/54) of Giardia positive cats were infected with a ensemble AI.Canada, Italy, Japan, , Brazilian and Germany reported cats infected with set A. In Australia, cats seem to have greater diversity , including collections of adapted canines C and D.
The importance of molecular detection
In order to determine the collection of Giardia infected animals, molecular detection must be performed by commercial laboratories. The importance of knowing whether a cat carries potential zoonotic giardia depends on the individual situation. It is important to remember that although cats have reported a collection of potential zoonotic diseases, the combination F that infects their own host adaptation is the most common, and is much less likely to have zoonotic diseases. Therefore, the risk of transmission to the owner is very low. In families with severe immunodeficiency, the risk can be increased, but the risk can be reduced by maintaining good hygiene for pets and people. Taken together, these factors greatly reduce the need to identify a collection of Ahzidi flagellar worms in each infected cat entering the clinic. Duodenum Giardia is a protozoa parasite that usually infects a variety of mammals, including cats, dogs and humans. Giardia is a species complex that includes at least 8 genetically distinct but morphologically identical sets (named A to H), with cats most frequently infected with set F. Giardia may be zoonotic because animals sometimes hide collections A and B, which more often infect humans, but no reports of Giardia collections from cats (F) or dogs (C and D) adapted hosts in the United States. Giardia infection in cats can be subclinical, but the most common clinical symptom is diarrhea. Historically, Giardia infection was diagnosed by microscopy of feces, but immunologic tests for detecting antigen in feces have now been widely used as a bedside test. However, even with improved diagnostic tools, Giardia infection in cats remains a difficult problem, as treatment is not always 100% effective, reinfection is common, and concerns about the possibility of zoonotic diseases remain. giardia spreads through feces-oral pathway. The cysts fall off in the feces and are immediately contagious after being excreted. Cysts can be directly ingested from infected hosts, contaminated food or water, or contaminated contaminants in the environment. Each cyst contains 2 trophoblasts, which appear when the cyst reaches the small intestine (decapsulation). Trophoblasts are the pathogenic stage of parasites. They reproduce by longitudinal dichotomy , either free in the cavity, or adhere to the mucosa using abdominal suction cups, resulting in malabsorption and fatty diarrhea. The trophoblasts undergo encapsulation as they move towards the colon, forming new cysts. Environmentally resistant cysts fall out intermittently in the feces. Trophoblasts can also be occasionally transmitted through diarrhea, but they are non-infectious and do not persist in the environment. Cats have a jaundice incubation period of 5 to 16 days, and cyst shedding is usually periodic. It should be noted that pets, especially cats, may ingest the cysts from the contaminated fur when combing their hair. Acute or Chronic diarrhea is the most common clinical symptoms of infection, which can lead to weight loss and the infected kittens cannot gain weight. In clinically infected cats, the feces are usually soft and pale in color, and also contain increased neutral fat and are described as more foul than normal. In order to determine the best test (microscopy, immunology, molecule) to detect Giardia infection, a large number of diagnostic comparison studies have been conducted, but there is only one common result-no single test can detect all infections. The Companion Animal Parasites Committee (CAPC) recommends that direct smear and centrifugal fecal floating should be performed when detecting symptomatic cats (and dogs) infection in clinically, combined with veterinary-approved sensitive and specific patient-side antigen testing. This combination of diagnostic tests maximizes the chances of detecting giardia. is difficult to diagnose Giardia by microscopy alone for many reasons: the cysts are small (10 to 12μm long; (Figure 1), intermittent shed, transparent, fragile in flotation solution. In conventional clinical practice, antigen detection for humans is not used in cats or dogs, as they are not optimized or approved for clinical use in animals. Figure 1. Duodenal giardia cysts (arrows) are recovered by centrifugation of fecal flotation with zinc sulfate; hookworm eggs (asterisk). spread and life cycle
Clinical symptoms
Diagnosis
Reference laboratories and some university laboratories can perform molecular tests to detect giardia stools in feces DNA, but is usually more expensive than performing or sending tests for fecal floating or using patient-side antigen detection. Polymerase chain reaction (PCR) assays available in commercial laboratories usually do not include genotyping or sequencing to determine the collection of giardia.
It is particularly important to note that, according to the recommendations of CAPC, patient-side antigen detection is only used in symptomatic patients (intermittent or persistent diarrhea). If clinical symptoms are not eliminated, subsequent tests for centrifugal fecal floating should be performed within 24 to 48 hours after treatment, rather than antigen detection.The timing of subsequent testing is crucial because the cat's Giardia incubation period is as short as 5 days and must be tested before this time has passed. Usually, suspected drug resistance or treatment failure is actually reinfection, and if subsequent testing is performed after 5 days or more, the source of infection cannot be determined.
Popularity
Giadi genus is distributed worldwide and can be found in every region of the United States. The prevalence of the genus Giardia infection in cats varies by population (e.g., individual pets, group pets, breeding groups, shelter animals, stray animals), geographical location, and the diagnostic method used.
For example, in a survey of patient-side antigen tests in symptomatic cats across the United States, 10.8% (512/4977) of cats tested positive for Giardia. Another survey found that 31% (36/117) of the cats tested from the international cathouse were infected with the Giardia flagellum. In 2020, the national prevalence of giardia in American cats was 4% (Figure 2). These data were derived from more than 1.8 million cat feces samples by CAPC, but since they did not include cats or stray cats who did not visit the veterinary and not all veterinary clinics use reference labs, 4% can be considered as the lowest baseline prevalence of essentially asymptomatic individuals.
Figure 2. Prevalence of giardia sapilla in the United States in 2020. Based on data from the Companion Animal Parasite Committee, fecal test results from AntechDiagnostics and IDEXX laboratories were compiled. Data are derived from the Companion Animal Parasite Committee Parasite Epidemic Map.
Treatment of
In the United States, there is no approved drug for the treatment of cat Giardia. However, it is safe to treat infection in cats with feline (metabolismol after oral administration) and febendazole and metronidazole and have varying degrees of efficacy. Metronidazole (25mg/kg) is taken orally twice a day for 5-7 days and can successfully remove the Giardia infection in experimentally infected adult cats. Fibantel (37.8 mg/kg) is a combination product containing both pyrantol (7.56 mg/kg) and pyraquantel (7.56 mg/kg). After 5 days of administration, the infection in the experimentally infected kittens was successfully cleared.
CAPC recommends treating Giardia infection in cats with fenbendazole (50mg/kg) for 5 consecutive days or metronidazole (25mg/kg) twice a day for 5 consecutive days. However, there are some safety issues with using metronidazole in cats, and cats with pregnant or breastfeeding and cats with epilepsy or liver disease should avoid metronidazole.
A preliminary study of secnidazole (30mg/kg) in 18 experimental cats found that it was effective in eliminating cyst shedding, but the follow-up period lasted only 8 days. In addition, 11 of the 18 cats experienced excessive saliva secretion after administration, and 4 of the 18 cats suffered from loss of appetite for 2 days. However, because the number of cats in each trial was small and there was no comparison with metronidazole or fenbendazole, there were some limitations in the study.
Prevention
It is difficult to completely eliminate the giardia worms because once the cyst falls off, it will be infected immediately and it is very likely to be infected again. Therefore, preventing feces from contaminating the environment is crucial to preventing reinfection. It is recommended to take a bath to remove fecal debris containing cysts from the fur. It is also recommended to disinfect cathouses or homes, including cat bags, litter boxes and cat nests; quaternary ammonium salt products, boiling water and chlorine are considered effective for the cyst.
The impact of zoonotic
The focus of concern about the potential zoonotic diseases of Giardia is the collection of infections of humans and animals A and B. Collection A has different zoonotic potentials and is further divided into AI subtypes through AIV; humans appear to be infected with AI and AII, and animals are infected with AII, AIII and AIV. Therefore, ensemble AI seems to have the widest range of hosts.
Giardia colonies that infect cats and dogs are usually host-adaptive and have not been reported in the United States to infect humans in pets. These host adaptive populations are more common than any potential zoonotic population. However, it is reported that groups A and B infected cats, and it is these cases that pose the greatest zoonotic risk to people. A survey of Virginia cats found that 22% (12/54) of Giardia positive cats were infected with a ensemble AI.Canada, Italy, Japan, , Brazilian and Germany reported cats infected with set A. In Australia, cats seem to have greater diversity , including collections of adapted canines C and D.
The importance of molecular detection
In order to determine the collection of Giardia infected animals, molecular detection must be performed by commercial laboratories. The importance of knowing whether a cat carries potential zoonotic giardia depends on the individual situation. It is important to remember that although cats have reported a collection of potential zoonotic diseases, the combination F that infects their own host adaptation is the most common, and is much less likely to have zoonotic diseases. Therefore, the risk of transmission to the owner is very low. In families with severe immunodeficiency, the risk can be increased, but the risk can be reduced by maintaining good hygiene for pets and people. Taken together, these factors greatly reduce the need to identify a collection of Ahzidi flagellar worms in each infected cat entering the clinic.
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