Investigation of Factors Associated with Subclinical Infections of Giardia duodenalis and Cryptosporidium canis in Kennel-Housed Dogs (Canis lupus familiaris).

Giardia duodenalis and Cryptosporidium spp. are zoonotic protozoal pathogens, spread by a fecal-oral route, which can infect a wide range of hosts including but not limited to dogs and humans. Giardia was recently estimated to be present in 37% to 50% of kennel-housed dogs. Cryptosporidium infections in kennel-housed dogs have been reported in 7% to 21% of the population. The goal of this study was to define demographic factors and fecal scores associated with positive screening test cases of Giardia and Cryptosporidium in kennel-housed laboratory dogs in the state of Texas. Fecal samples were collected from 153 clinically normal laboratory dogs at an academic research facility and a local laboratory dog supplier. We used 3 diagnostic tests evaluated in parallel to determine test positivity to each organism: a human point-of-care coproantigen test, a direct immunofluorescent assay, and an in-house polymerase chain reaction. Dogs were significantly more likely to test positive for Giardia (45%) than Cryptosporidium (7%) (P < 0.01). Dogs that were 18 mo of age or younger had 3 times the odds (P = 0.009) of subclinical Giardia infection compared with older dogs. We found no significant relationship between age and Cryptosporidium prevalence. Dogs with hard feces (fecal score 1-2) at the time of screening had 0.34 times lower odds ( P = 0.049) of testing positive for Giardia than dogs with normal feces, but no statistically significant relationship was found between fecal score and Cryptosporidium -positive test status. With these findings, we demonstrated the value of considering age and fecal score when choosing which dogs to screen for subclinical Giardia. Additional studies with larger sample sizes should be conducted to determine the relationship between age and fecal score and subclinical Cryptosporidium infection.

Soil-transmitted helminth infections and anemia in children attending government run schools on Samosir Island, Indonesia.

Background: Worldwide, >654 million children live in regions where soil-transmitted helminth (STH) infections are endemic. These parasites cause a variety of symptoms, including anemia. Methods: In May 2023, fecal and blood samples were collected from children aged 6 to 11 years attending government run (public) elementary schools in the Simanindo and Ronggur Nihuta sub-districts of Samosir Island, Indonesia where a twice a year mass drug administration (MDA) program is currently in place. A questionnaire was administered to students' parents or adult family members on possible risk factors for STH infections. Qualitative data were collected through in-depth interviews and focus group discussions. Results: In total, 187 and 221 children in Simanindo and Ronggur Nihuta provided samples, respectively. The STH infection prevalence in Simanindo was 4.8% (9/187) and the infection prevalence in Ronggur Nihuta was 5.9% (13/221). In Simanindo, all infections were caused by Trichuris trichiura (n = 9), and in Ronggur Nihuta infections were caused by Ascaris lumbricoides (n = 6), Trichuris trichiura (n = 5), and A. lumbricoides + T. trichiura (n = 2). Three children had anemia but were negative for STH infections. While the results of the parent/adult questionnaires indicated access to a generally safe water supply and septic system, information from the in-depth interviews and focus groups revealed that the local water supply becomes greatly diminished during the dry season. Conclusions: While MDA has been shown to effectively control roundworms and hookworms, additional measures to control trichuriasis are needed. There is also a need for the government to invest in improving the public water supply infrastructure.

Mass Decontamination of Companion Dogs in Disaster: Planning for Personnel, Water, and Time Requirements.

OBJECTIVE: The importance of companion animals in the daily lives of people, and the increasing incidence and severity of natural disasters impacting people and their animals, is very well documented. However, despite the advancement of companion animal response capabilities, decontamination remains an inconsistently implemented component of disaster response. The challenge for local authorities is their need for planning factors and protocols specific to companion animal decontamination which are generally lacking. Data is provided on the average time requirements, water use and containment resources necessary, and the personnel required to decontaminate (decon) a large number of companion dogs. METHODS: Sixty-three lightly contaminated, medium weight, short to medium coat, highly tractable dogs (Labradors and Hounds) from a State facility colony were used to determine the water requirements, soap effectiveness, and time required to complete decon (washing/bathing). Data were collected over a 6-mo period using 2 personnel that were randomly assigned to wash the dogs. Difference in weight, bathing time, and water use between groups was evaluated using a 2-tailed 2-sample t-test for independent data. RESULTS: The time and water requirements were significantly different between medium coated dogs and short coated dogs. On average, for a short coated dog, the amount of time to complete decon was 7 min, and the amount of water was 8-10 gal. For medium coated dogs, the time increased to 10-12 min to complete the process and 12-15 gal water. DISCUSSION: The results of this study provide important insights emergency management planners, animal response team members, and community personnel tasked with implementation of mass decontamination of companion dogs following a natural or man-made disaster.

Monetary burden of neurocysticercosis on a hospitalized population in Muli County, China.

Neurocysticercosis (NCC) is a potentially life-threatening condition caused by the zoonotic cestode, Taenia solium. Pigs are the typical intermediate hosts for T. solium but humans can become infected and develop NCC upon ingesting parasite eggs that are shed in the feces of an infected person. The objective of this study was to estimate the monetary burden of neurocysticercosis (NCC) on hospitalized patients from Muli County, China. Muli is an agricultural county in Liangshan Prefecture, Sichuan Province, China where pigs are raised and the zoonotic cestode, Taenia solium, is endemic. Demographic and treatment data were collected from the Muli County Health Insurance Department on hospitalized individuals with an NCC diagnosis between 2014 and 2021. These patients represent residents of Muli County that purchased health insurance and received treatment in a public hospital in Sichuan Province. Hospital costs were converted from Chinese renminbi (RMB) to United States dollars (US$) for month and year of hospitalization and adjusted for inflation. Individuals with missing hospital information were excluded from analysis. For indirect costs, annual average salary for Liangshan Prefecture working-age adults was obtained to calculate productivity losses based on number of hospitalization days and travel days to and from the hospital. Transportation costs were evaluated based on estimated bus fare to and from the hospital. Out of 70 patients identified from 2014 to 2021, 68 had complete records, of which 47.1% were male (n = 33) and the median age at first hospitalization was 34 years. Total estimated cost for these patients was US$228,341.98. Direct costs contributed 62.5% (US$142,785.25) and indirect costs were 37.5% (US$85,556.73) of the total cost. The estimated median cost per case was US$2,078.69. Individuals with a single hospitalization (n = 41) cost a median of US$1,572.03 and those with multiple hospitalizations (n = 27) cost a median of US$4,169.95. The median total cost per NCC case was 18.6% of the average wage for a Liangshan Prefecture resident in 2021. While the study was limited to those with insurance coverage, monetary burden on the local population is likely substantial. Public health policies aimed at reducing transmission should be implemented to decrease the economic burden of NCC on this region.

A survey of the parasites of Ural saiga antelopes and Turkmenian kulans of Kazakhstan.

Saiga antelope and Turkmenian kulans are considered critically endangered and near threatened, respectively, by the International Union for Conservation of Nature (IUCN). Due to these species' fragile status, it is important to understand the pathogens infecting their remaining populations. A total of 496 faecal samples were collected from Ural saiga antelope in western Kazakhstan during June, September, and November of 2021 and May and August of 2022 and 149 faecal samples were collected from kulans in the Altyn-Emel nature reserve in south-eastern Kazakhstan from June to August of 2021. Additionally, endo- and ecto-parasites were collected from 17 saiga that were found deceased due to natural causes. Nine helminths (3 cestodes, 6 nematodes) and two protozoans were found in Ural saiga antelope. In addition to intestinal parasites, one case of cystic echinococcosis due to Echinococcus granulosus infection and one case of cerebral coenurosis due to Taenia multiceps infection was identified on necropsy. None of the collected ticks (all Hyalomma scupense) were found positive for Theileria annulate (enolase gene) or Babesia spp. (18 S ribosomal RNA gene) via PCR. Three intestinal parasites (Parascaris equorum, Strongylus sp., and Oxyuris equi) were found in kulans. All identified parasites, in both saiga and kulans, are also found in domesticated livestock, suggesting a need for better understanding of how parasites are maintained within and between regional wild and domestic ungulate populations.

Heartworm (Dirofilaria immitis) in carnivores kept in zoos in Texas, USA: risk perception, practices, and antigen detection.

BACKGROUND: Dirofilaria immitis is the causative agent of heartworm disease in wild and domestic canids, felids, and mustelids. Recent studies demonstrate that additional families in the order Carnivora are also susceptible to infection. Therefore, the objectives of this study were to (1) better understand current practices surrounding heartworm prevention and diagnostics in zoological facilities located in the state of Texas, USA, and (2) assess archival serum samples of carnivores kept in these facilities for the presence D. immitis antigen and/or antibody. METHODS: A questionnaire was completed by veterinarians or veterinary technicians representing 10 zoological facilities across Texas. This questionnaire was designed at the taxonomic family level, encompassing the 12 terrestrial carnivore families Ailuridae, Canidae, Eupleridae, Felidae, Herpestidae, Hyaenidae, Mephitidae, Mustelidae, Prionodontidae, Procyonidae, Ursidae, and Viverridae. The second objective was achieved with the use of archival serum samples made available by six zoo facilities. RESULTS: Risk perception varied across facilities for every family, including among species belonging to Canidae. All facilities used monthly heartworm prevention in canids and felids, with more variation existing in the other families. The use of diagnostic testing and type and route of administration of preventive varied by facility, with oral ivermectin the most commonly used preventive. A total of 217 archival serum samples, belonging to 211 individual animals encompassing 11 families and 39 species, were tested with a commercial heartworm antigen ELISA test, pre- and post-immune-complex dissociation. A subset of samples was also assessed for the presence of feline anti-heartworm antibodies using a commercial ELISA test. Two animals, both of which were Asian small-clawed otters from the same facility, had antigen detected (0.95%). CONCLUSIONS: This study demonstrates that while the zoo veterinary community is aware of the risk and health impact of heartworm disease in canids and felids, there is still a great deal of uncertainty regarding the risks and ideal strategies for prevention in other carnivore families. The low proportion of antigen detection may serve as a baseline for future prevalence studies across the southern United States, where there is an emerging concern of macrocyclic lactone resistance in heartworm.

Toxocara canis seropositivity in different exposure groups in the Khyber Pakhtunkhwa province of Northwest Pakistan.

Human toxocariasis is a highly prevalent zoonosis worldwide but is underreported in most countries. This study was conducted to evaluate Toxocara canis seropositivity in different exposure sub-groups located in the Mardan, Swabi, and Nowshera districts of the Khyber Pakhtunkhwa province of Northwest Pakistan. A total of 400 blood samples were collected from males 15 years of age and older with no animals, with livestock, with dogs and/or cats living in the house, and from butchers and veterinarians or para-veterinarians. Serum was tested using a commercial ELISA kit for detection of IgG antibodies against T. canis. Proportion seropositive was presented for each group and differences between groups were evaluated using the chi-square or Fisher's exact test as appropriate. Possible risk factors obtained through administration of a questionnaire were also evaluated for each sub-population. Overall T. canis seroprevalence was 14.2%, with a significant difference found between the seroprevalence of individuals with no animals (5.0%; 5/100), individuals with dogs and/or cats living in the household (8.0%; 8/100), individuals with livestock (18.0%; 18/100), veterinarians or para-veterinarians (24.0%; 12/50), and butchers (28.0%; 14/50) (p < 0.001). Significant differences in seropositivity by income bracket, education level, and working in the fields were found for some sub-groups. Study findings demonstrate that certain sub-populations, in Northwest Pakistan, may be at greater risk of T. canis infection. Development and implementation of targeted preventive strategies may, therefore, be needed.

Prevalence and Seasonality of Adult and Arrested Larvae of Gastrointestinal Nematodes of Sheep from Mashhad City, Northeastern Iran.

Background: This study was conducted to determine the prevalence and intensity of nematode infections in sheep located in northeastern Iran from Apr 2018 to Mar 2019. Methods: Gastrointestinal nematodes of 300 sheep were inspected. The season of slaughter, anatomic location where the parasite was located, the animal's sex, infection prevalence and intensity were recorded. Seasonal differences in arrested larvae numbers also were assessed using Cochran's Q test. Results: Overall, 4,331 adult nematode specimens were collected. Among the examined sheep, 53% (159/300) were infected with one or more nematode species. Among infected sheep, 42.8% were infected with a single species of nematode, 26.4% were infected with two species of nematodes, and 30.8% were infected with three or more species of nematodes. Marshallagia marshalli (13.3%) was the most common nematode recovered from the abomasums of infected sheep, while Trichostrongylus vitrinus (4.6%) was commonly recovered from the small intestines, and Trichuris ovis (25.6%) was commonly recovered from the large intestines. In total, 463 arrested larvae were found in the abomasums of 7.5% of infected sheep and 104 arrested larvae were found in the small intestines of 8.8% of infected sheep. A significantly higher numbers of arrested larvae were found in summer compared to autumn (P<0.001). Conclusion: Intestinal parasites continue to be a problem for sheep in northeastern Iran and additional control measures need to be explored.

Sequestration and Destruction of Rinderpest Virus-Containing Material 10 Years after Eradication.

In 2021, the world marked 10 years free from rinderpest. The United Nations Food and Agriculture Organization and World Organisation for Animal Health have since made great strides in consolidating, sequencing, and destroying stocks of rinderpest virus-containing material, currently kept by only 14 known institutions. This progress must continue.

What is the value of statistical testing of observational data?

Statistical analysis of medical data aims to reveal patterns that can aid in decision making for future cases and, hopefully, improve patient outcomes. Large and bias-free datasets, such as those produced in formal randomized clinical trials, are necessary to make such analyses as reliable as possible. For a host of reasons, randomized trials are, unfortunately, relatively uncommon in veterinary medicine and surgery, implying that less ideal datasets (mostly observational data) must form the basis for much of our decision making regarding treatment of individual patients under our care. In this review, we first describe the common shortcomings of many observational veterinary datasets when viewed in comparison with their optimal counterparts and highlight how the deficiencies can lead to unreliable conclusions. We illustrate how many of the interpretative problems associated with observational data, predominantly various forms of bias, are not solved, and may even be exacerbated, by statistical analysis. We emphasize the need to examine summary data and its derivation in detail without being lured into relying upon P values to draw conclusions and advocate for completely omitting statistical analysis of many observational datasets. Finally, we present some suggestions for alternative statistical methods, such as propensity scoring and Bayesian methods, which might help reduce the risk of drawing unwarranted, and overconfident, conclusions from imperfect data.

The prevalence of human trichuriasis in Asia: a systematic review and meta-analysis.

Trichuriasis is one of the most common soil-transmitted helminth (STH) infections, affecting populations globally. The condition is particularly prevalent in tropical and subtropical areas with low levels of sanitation and poor living conditions. The objective of this systematic review and meta-analysis was to evaluate the prevalence of Trichuris trichiura infection in Asia at the country and region level. Multiple databases/academic search engines (Web of Science, PubMed, ProQuest, Scopus, and Google Scholar) were searched for literature on T. trichiura prevalence in Asia published through January 2021. Pooled prevalence was determined using the meta-package in R (version 3.6.1). Out of 13,836 articles, 226 studies (5,439,500 individuals) from 26 countries met the inclusion criteria. Of the 226 studies, 151 were community-based studies that included individuals across the age spectrum, while 75 studies focused on school children (typically in the 5-16 years age range). The overall T. trichiura pooled prevalence was 15.3% (95% CI: 12.4-19.1%), with a pooled prevalence of 13.3% (95% CI: 10.0-17.1%) for the community studies and 20.9% (95% CI: 14.7-27.9%) for the studies only including school children. For studies including all age groups, individuals in the 1-15 years age group had the highest pooled prevalence at 23.4% (95% CI: 1.7-49.4%). There was a significant difference found in overall pooled prevalence by sex (p < 0.001) and community type (rural versus urban) (p < 0.001). Although prevalence appears to be decreasing, study findings suggest that T. trichiura infection continues to be a public health problem in Asia. Therefore, control programs focused on at-risk individuals in endemic areas are needed.

Implementation of Taenia solium control measures in Bali, Indonesia: Survey findings and a historical overview.

Historically, cysticercosis cases caused by infection with the larval stage of the Taenia solium tapeworm have occurred sporadically in Bali, with taeniasis carriers found primarily in villages located in the Kubu subdistrict of Karangasem. As Bali is a well-known tourist destination, living standards are relatively high on the island, except for an area located beneath the northeast slope of the active volcano Mt. Agung (Alt. 3031 m), which includes Kubu. Over the last 30 years, pigs originating from this area have been found with T. solium cysticerci, whereas pigs from other parts of the island have not been shown to be infected. Out of 108 individuals screened via fecal sample examination in Kubu during 2019, 3 cases of T. solium taeniasis (2.8%) were identified. There was no significant difference in taeniasis prevalence from surveys conducted in 2011-2016 (1.0%, 11/1089) (p = 0.123). Out of 110 humans and 140 pigs tested serologically in Kubu during 2019, no cases of cysticercosis were identified. This is in contrast to a seroprevalence of 4.1% (42/1025) in humans during 2011-2016 and a seroprevalence of 13.1% (43/329) in pigs during 2011-2013. Over the last decade, improved drinking water and sanitary systems have been employed in addition to health education targeting primary school children, including emphasis on washing hands before eating and after defecation. This review provides previously unpublished survey data and a historical overview of T. solium infection in Bali and offers guidance on best practices to ensure that remaining pockets of transmission are addressed.

New insights on the Taenia solium tapeworm using molecular tools: age-based human definitive host prevalence and deliberation on parasite life span.

Information on age-based Taenia solium taeniasis prevalence is crucial for control of cysticercosis. T. solium taeniasis prevalence was determined for a village in Liangshan Prefecture, Sichuan Province, China that was co-endemic for T. solium, Taenia saginata asiatica, and Taenia saginata. Individuals who were Taenia egg-positive by stool microscopy and/or expelled tapeworms or proglottids post-treatment were diagnosed as having taeniasis. Infecting species was identified via multiplex PCR on tapeworm specimens or coproPCR followed by sequencing. In addition, initial stool samples from 10 children with taeniasis suspected of having spontaneous expulsion of tapeworms within the period between diagnosis and treatment were subject to species confirmation via coproPCR and sequencing. Of the 389 study subjects, 194 (49.9%) were diagnosed with taeniasis. Children (< 16 years of age) had a higher T. solium taeniasis prevalence (8.8%) than older individuals (2.5%) (P = 0.0127). Molecular analysis of initial stool samples from 7 of 10 children suspected of spontaneously passing tapeworms indicated 6 infections due to T. solium and 1 infection due to T. saginata. This study found that young children had a higher T. solium taeniasis prevalence than older individuals, providing additional support for the belief that adult T. solium likely has a relatively short lifespan compared to other Taenia species with human definitive hosts.

Ultrasound-based evaluation of the prevalence of abdominal cystic echinococcosis in the Turkestan region of Kazakhstan.

BACKGROUND: Human cystic echinococcosis (CE) is a zoonotic disease caused by Echinococcus granulosus sensu lato. CE is known to be endemic in some parts of Central Asia. We present findings from an ultrasound-based survey to estimate the prevalence of CE in the Turkestan oblast of Kazakhstan. METHODS: In October 2019, six villages were chosen based on records from a national surveillance dataset. Inhabitants aged 5-90 y were invited to undergo a free abdominal ultrasound to screen for CE cysts. All identified cysts were staged according to the WHO-endorsed classification for CE cysts. RESULTS: A total of 2252 individuals underwent ultrasound screening. Twenty-two (0.98%) individuals had CE, with a combined total of 33 cysts: 25 (75.7%) inactive (14 CE4, 11 CE5) and 8 (24.3%) active/transitional (2 CE1, 1 CE2, 3 CE3a, 2 CE3b). One patient had a postsurgical cavity. Sixty-eight patients (3.0%) reported CE prior to surgical treatment. In 25 (36.8%) previously diagnosed patients, albendazole prophylaxis was not used. CONCLUSIONS: CE is endemic in the study region, with ongoing transmission. The number of surgically treated CE patients suggests an underestimation of the disease burden by the current surveillance system. Further studies on local CE epidemiology and the implementation of expert treatment recommendations are needed.

Trends in the Surgical Incidence of Cystic Echinococcosis in Uzbekistan from 2011 to 2018.

Cystic echinococcosis (CE) is a zoonosis with a cosmopolitan distribution caused by Echinococcus granulosus sensu lato tapeworms. Although Uzbekistan and other countries in Central Asia are considered endemic, estimates of disease burden are lacking. We present data regarding surgically managed cases of CE obtained from Uzbekistan's national disease surveillance registry. These data are from medical centers in Uzbekistan authorized to treat the disease and reported to the Uzbek Center for Sanitation and Epidemiology from the period 2011 to 2018. Information included patient age class (children 14 years or younger versus adults 15 years and older), but no data regarding cyst location. Incidence rates were calculated using data from the national population registry, and the Cuzick nonparametric test for trends was used to test for differences in the incidence over time at the country and regional levels. A total of 7,309 CE cases were reported. Of these, 857 (11.73%) involved pediatric patients. The mean incidence rates were 4.4 per 100,000 population in 2011 and 2.3 per 100,000 population in 2018 (P = 0.016). One region (Republic of Karalpakistan) showed a nonstatistically significant increase (P = 0.824). All other regions except three showed a statistically significant decrease. We present data showing a decrease in the overall incidence of surgically treated CE in Uzbekistan from 2011 to 2018. However, the presence of cases involving children suggests ongoing parasite transmission. The absence of clinical information (starting with cyst stage and localization) needs to be addressed to improve the national surveillance system. Field studies are also needed to further explore the epidemiology of CE in the country.

Genetic Diversity of Taenia solium and its Relation to Clinical Presentation of Cysticercosis.

In this perspectives paper, we discuss fertilization strategies for Taenia saginata and Taenia saginata asiatica as well as heterogeneity in Taenia solium, the causative agent of human cysticercosis. Two different genotypes of T. solium (Asian and Afro/American) were confirmed by mitochondrial DNA analysis approximately two decades ago. Since then, outcrossings of the two genotypes have been identified in Madagascar where the two genotypes are distributed sympatrically. Outcrossings were confirmed by the presence of discordance between mitochondrial and nuclear DNA. Since multiple tapeworm infections are common in endemic areas, outcrossing events likely occur quite frequently. Therefore, mitochondrial DNA from T. solium specimens collected from humans and pigs in endemic areas should be analyzed. If variations are found between specimens, nuclear DNA analysis should be performed to confirm the presence of discordance between mitochondrial and nuclear genes. Additional outcrossings likely add complexity to understanding the existing genetic diversity. Serological surveys are also recommended since serodiagnostic glycoprotein can also differentiate between the two genotypes. Viable eggs from different genotypes or from hybrids of two different genotypes should be used for experimental infection of pigs or dogs in order to observe any pathological heterogeneity in cysticercosis development. Although genetic diversity of T. solium is expected to result in clinical heterogeneity of cysticercosis in humans and pigs, there is currently no evidence showing that this occurs. There are also no comparative experimental studies on this topic. Therefore, studies evaluating the link between parasite heterogeneity and clinical outcome are warranted.

Estimation of the monetary burden of treated human cystic echinococcosis in Pakistan.

Cystic echinococcosis (CE), caused by the larval stage of Echinococcus granulosus sensu lato tapeworms, continues to be a public health problem in many endemic countries, including Pakistan. Patient level data, including age, sex, and cyst(s) location for surgically managed CE patients for the years 2013-2016 from hospitals located in Punjab and Khyber Pakhtunkhwa provinces were obtained from medical charts. Direct and indirect costs associated with surgically managed CE patients treated in private and public hospitals were then estimated and applied to country-level case numbers estimated through the Global Burden of Disease Study. A total cost of US$4,068,666 (95% CI: US$3,097,684 - US$5,295,702) was estimated for the year 2017, with US$3,951,853 (95% CI: US$2,981,400 - US$5,177,610) attributable to direct diagnosis and treatment-related costs and US$117,137 (95% CI: US$91,841 - US$146, 979) attributable to wage losses during the treatment period. Mean direct cost per patient (US$1,056) was approximately 72% of the country's per capita gross domestic product (GDP). Surgical management continues to be the treatment of choice for CE patients in Pakistan. If physicians were to adhere to World Health Organization Informal Working Group on Echinococcosis (WHO-IWGE) cyst stage-specific treatment guidelines, it is likely that the number of surgical interventions would decrease as would treatment costs.

Evaluation of zoonotic platyhelminthe infections identified in slaughtered livestock in Iran, 2015-2019.

BACKGROUND: Platyhelminth infections of livestock can result in considerable economic losses. This study aims to evaluate the spatial frequency of cystic echinococcosis (CE), dicrocoeliasis, and fascioliasis in livestock slaughtered in Iran during the years 2015-2019 and estimate direct costs associated with organ condemnation due to these parasites. METHODS: Abattoir data from 413 abattoirs representing all 31 Iranian provinces were collected from the Iran Veterinary Organization. Infection prevalence was calculated per year at the province level. The Local Moran's I statistic was performed to evaluate spatial autocorrelation of animals positive at slaughter for the years 2015-2019. Direct costs associated with condemned livers were calculated for each parasitic condition, with costs associated with condemned lungs also included for CE. RESULTS: Overall prevalence values for the study timeframe were as follows: sheep and goat fascioliasis 1.56% (95% CI: 1.56-1.56%), cattle fascioliasis 3.86% (95% CI: 3.85-3.88%), sheep and goat dicrocoeliasis 4.63% (95% CI: 4.62-4.63%), cattle dicrocoeliasis 3.08% (95% CI: 3.07-3.09%), sheep and goat CE 5.32% (95% CI: 5.32-5.33%), and cattle CE 7.26% (95% CI: 7.24-7.28%). Northwest Iran had the highest prevalence of CE and fascioliasis. High infection areas for Dicrocoelium spp. included the provinces of Zanjan, Gilan, Qazvin, and Tehran, which are located in northern Iran. Direct economic losses for sheep and goat fascioliasis, dicrocoeliasis, and CE for the study period were US$13,842,759, US$41,771,377, and US$22,801,054, respectively. Direct economic losses for cattle fascioliasis, dicrocoeliasis, and CE for the study period were US$1,989,200, US$1,668,986, and US$2,656,568, respectively. CONCLUSION: Our findings provide valuable data for future monitoring of these important parasitic diseases in Iranian livestock. Disease control strategies are required to reduce the economic and public health impact of these platyhelminths.