IJMPES International Journal of http://ijmpes.com Medical Parasitology & doi 10.34172/ijmpes.2020.19 Vol. 1, No. 3, 2020, 65-69 Epidemiology Sciences eISSN 2766-6492 Original Article Evaluation of the Effects of Toxoplasmosis in Small Ruminants on the Epidemiology of Human Toxoplasmosis by Indirect ELISA in Kaleybar Region, North West of Iran Yaghoub Firouzivand1* ID , Behrad Khan Ahmadi2 ID , Mustafa Afsari3 1Department of Pathobiology, Malekan Branch, Islamic Azad University, Malekan, Iran 2Clinical Research Development Center, Imam Khomeini and Mohammad Kermanshahi and Farabi Hospitals, Kermanshah University of Medical Sciences, Kermanshah, Iran 3Young Researchers Club, Shabestar Branch, Islamic Azad University, Shabestar, Iran Abstract Introduction: Toxoplasma gondii is an intracellular protozoan that causes toxoplasmosis in humans and domestic animals. It causes abortion, especially in small ruminants. Sheep and goats have a significant role in the maintenance and survival of the parasite as well as its transmission to humans. Therefore, the aim of this study was to evaluate the seroprevalence of toxoplasmosis in small ruminants in Kaleybar region, East Azerbaijan province, using Indirect ELISA. Materials and Methods: In this study, blood samples of 270 sheep and goats were collected from October 2019 to December 2019 and anti-Toxoplasma IgG antibodies in sera were evaluated using indirect ELISA. Data analysis was performed using chi- square test in SPSS version 24.0. A P value of less than 0.05 was considered statistically significant. Results: Totally, 26 of 270 (9.62%) animals had anti-Toxoplasma gondii antibodies in their sera. Analysis showed that sheep were more susceptible to toxoplasmosis than goats and 21 (10.5%) sheep and 5 (7.14%) goats were seropositive for T. gondii; however, there was no statistically significant difference (P=0.413). The highest frequency (15.87%) of infection was observed in sheep and goats aged 3-4 years, respectively. Moreover, the rate of infection was higher in female (22/205) animals than in males (4/65); however, the relationship between gender and age and the frequency of positive samples was not significant (P=0.276 and P=0.121). Conclusions: The results of this study indicated that the seroprevalence of Toxoplasma gondii infection in small ruminants of the Kaleybar region (North West of Iran) is relatively low compared to other parts of the country. Further studies should be conducted on the rate of infection in definitive hosts of T. gondii in the region as a potential source of human infection. Keywords: Epidemiology, Toxoplasmosis, ELISA, Kaleybar region, Iran Received: June 12, 2020 , Accepted: August 5, 2020, ePublished: October 14, 2020 Introduction Toxoplasmosis is one of the most important parasitic Toxoplasma gondii, an obligate intracellular protozoan zoonotic diseases, so it has been the most commonly parasite (phylum Apicomplexa, subclass Coccidia), studied coccidian parasite (7). infects many different types of hosts and different host Sheep and goats acquire the infection after contact tissues, and it is the causative agent of toxoplasmosis (1). with infected cats and ingesting oocytes scattered in the The parasite is only able to complete its sexual life cycle environment (8) or by ticks (9). In the intermediate hosts, in felids as definitive hosts and oocysts produced are even the ingestion of 10 sporulated oocysts can cause excreted through the feces of the host. Sporulated oocysts infection. contaminate the surrounding environment and pastures In addition, lambs and goat kids can be exposed to T. (2,3). Toxoplasmosis is a serious health problem in many gondii by consuming the milk of ewes and goats naturally parts of the world (4). infected with the parasite and the establishment of T. According to studies, the global rate of human gondii infection in the muscles of lambs and even eating toxoplasmosis is between 1.3% and 98.4% (5), in addition small pieces (5-10 g) of their uncooked meat can transmit to the fact that more than 30% of Iranians are infected the infection to humans (10). Human infection occurs with Toxoplasma gondii (6). in a variety of ways, such as ingesting sporulated oocytes *Corresponding Author: Yaghoub Firouzivand, Email: [email protected] Open Access Scan to access more free content Firouzivand et al released in water and food or by consuming undercooked and animal husbandry are flourishing in this region. or uncooked meat containing viable T. gondii cysts (10- 12), as well as vertical transmission (13). Toxoplasmosis Blood Sample Collection causes serious complications in humans, especially Blood samples of 270 randomly selected animals (200 neonates, as well as immunocompromised individuals sheep and 70 goats) were collected from October to (14, 15). December 2019. For the evaluation of seropositivity, Generally, small ruminants are highly susceptible to 5 mL of blood was drawn from the jugular vein using T. gondii infection. The infection is not associated with sterile disposable syringes. After blood sampling, any specific symptoms (16); however, the main problem specimens were centrifuged at 3000× for 10 minutes and for pregnant animals is that the parasite causes early immediately after the separation of serum, these serums embryonic death, foetal resorption, mummification, were kept in sterile microtubes at -20°C until use for stillbirth (10,17) that lead to significant economic and serological examinations. Serum samples were evaluated reproductive losses (18,19). In sheep, infection with the in the laboratory by ELISA. parasite in early pregnancy poses a greater risk to the fetus compared to late pregnancy (20). In many countries Indirect ELISA including Iran, breeding livestock such as sheep and goats Indirect ELISA method was used according to the is booming and the milk and meat of these animals are protocol provided by Izadyar et al in 2019 (26) with some widely used as food sources (21). Toxoplasmosis of goats modifications. In brief, 96-well Strip Microplate (SPL, and sheep is affecting the lives of people whose source of Korea) was coated with 100 μL of antigen (90 μg/mL) in income is the production of ruminant meat and milk (22). buffer (NaHCO3 – Na2CO3, pH 9.6) and the overnight Considering the role of sheep and goats in maintaining incubation was performed at 4°C. After the wells were and transmitting the infection to humans, research on washed thrice with TBS, the blocking was performed at the detection of T. gondii infection in livestock for human room temperature for 2 hours using 1% bovine serum consumption is very important (2). albumin in PBS. The wells were then washed with TBS Many studies on toxoplasmosis in small ruminants have three times as mentioned above and then 100 μL of serum been performed in different regions of the world. samples from sheep and goats and from positive and According to previous studies, the prevalence of negative controls were added to each well after dilution toxoplasmosis ranges between 3% and 98% (2) in sheep and incubated at 37°C for 1 hour. After incubation, the herds and it ranges from 5.6% to 62% in goats around wells were washed and 100 μL of 1:5000 dilution of HRP the world (2). In seroprevalence studies conducted on (rabbit anti-sheep/goat IgG-horseradish peroxidase) sheep and goats in different areas of Iran for T. gondii, conjugated antibody (Razi BioTech, Iran) was added to seropositivity was determined to be between 3.3% each well and incubated for 1 hour at 37°C. Eventually, and 36.8% in sheep (23) and 27% in goats, respectively the wells were washed five times with TBS, and 50 μL of (19). In general, various methods are used to diagnose 3,3′,5,5′-tetramethylbenzidine (TMB) substrate solution toxoplasmosis, including direct methods (such as (Razi BioTech, Iran) was added and incubated in the dark immunohistochemistry, histopathology, and PCR) and for 20 minutes at room temperature. To stop the reaction, indirect methods (such as indirect fluorescent antibody 25 μL of 2 M H2SO4 (stop solution) was added to each test, Sabin-Feldman dye test, ELISA, and hemagglutination well after 10 minutes. Optical density (OD) at 450 nm was test) (24). In live animals, the ELISA method can be used measured using ELISA reader (Stat Fax, USA). as a suitable test to detect antibodies against T. gondii (25). Considering the economic importance of abortion in Statistical Analysis sheep and goat herds and the possibility of transmitting Statistical analysis of the data was performed using chi- the disease to humans via the consumption of livestock square test in SPSS version 24.0. products, this study was performed to evaluate the seroprevalence of toxoplasmosis in small ruminants for Results the first time in Kaleybar region, East Azerbaijan province. Totally, the sera of 270 animals (200 sheep and 70 goats) were examined and 10.5% (21/200) of sheep and 7.14% Materials and Methods (5/70) of goats were seropositive for T. gondii; however, Study Area no statistically significant relationship was found between Kaleybar region is located in the northeast of East animal species and serum positivity (P=0.413). Azerbaijan province with a population of about 48837, at Serological results are summarized in Table 1. 38° 52’ North latitude and 47° 25’ East longitude from the Considering the age of animals, the highest and lowest meridian, and its altitude from sea level is 1144 m. Its area number of positive cases were found in the age groups of is about 3,702 km2 with a mean annual rainfall of 372 mm 3-4 years (15.87%) and 1-2 years (5.26%), respectively; and its mean temperature varies from 2.2 to 23.9°C. The however, the relationship between age and frequency climate of Kaleybar is cold and temperate. Agriculture of positive cases of toxoplasmosis was not significant 66 Int J Med Parasitol Epidemiol Sci Volume 1, Number 3, 2020 Firouzivand et al Table 1.