Ann Ig 2020; 32(1): 50-55 doi:10.7416/ai.2020.2329 Toxoplasmosis in Nomadic Communities: A Seroepidemiological Study in Southwestern Iran N. Arefkhah1, B. Sarkari1,2, S. Rozrokh1, Z. Rezaei1,3, A. Moshfe4 Key words: Toxoplasmosis, seroepidemiology, nomads, Iran Parole chiave: Toxoplasmosi, sieroepidemiologia, nomadi, Iran Abstract Background. Toxoplasma gondii is the agent of a zoonotic protozoan infection with worldwide distribution. The rates of infection in different areas are depending on climatic conditions and also social and cultural habits of the people. This cross-sectional study aimed to find out the seroprevalence of toxoplasmosis in nomadic people in Boyer-Ahmad County, in the southwest of Iran. Methods. Blood samples (5 mL) were collected from 1005 individuals of nomadic tribes of Boyer-Ahmad County in Kohgiluyeh and Boyer-Ahmad Province in 2016. A predesigned questionnaire, containing basic epidemiological information was filled out for each subject during the sampling. Sera were evaluated for anti-T. gondii antibodies (both IgG and IgM), using a commercial ELISA kit. Collected data were analyzed by SPSS, using descriptive statistics and Chi-square test. Results. Out of the 1005 studied subjects, 227 (22.6%) were male and 778 (77.4%) were female. The mean age of participants was 41 years (SD: ±17). The most represented (24.4%) age class was 21-30 years and the least (1.9%) 1-10 years. Anti-T. gondii antibodies were detected in 174 (17.3%) of the cases. No stati- stically significant associations were found between seropositivity to T. gondii and area of residence, age, gender and educational levels of the participants. Conclusions. Findings of this study show that the seroprevalence of toxoplasmosis among the nomads of Kohgiluyeh and Boyer-Ahmad province is alike to other communities in our country. Further study is required to elucidate the genotype of T. gondii in this community. Introduction Although toxoplasmosis is a self-limiting infection in most of the immunocompetent Toxoplasma gondii (T. gondii) is a individuals, it may be associated with zoonotic protozoan parasite with diverse severe disease and serious complication prevalence rates among different populations such as encephalitis, brain abscesses and and regions of the world (1-3). Toxoplasmosis death in immunocompromised subjects emerges as a life-threatening infection in the (4, 6). Human infections with T. gondii immunocompromised individuals and in usually occur through consumption of raw case of congenital infection (4-8). bradyzoite-containing meat, ingestion of 1 Department of Parasitology and Mycology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran 2 Basic Sciences in Infectious Diseases Research Center, Shiraz University of Medical Sciences, Shiraz, Iran 3 Professor Alborzi Clinical Microbiology Research Center, Nemazee Hospital, Shiraz University of Medical Sciences, Shiraz, Iran 4 Cellular and Molecular Research Center, Yasuj University of Medical Sciences, Yasuj, Iran Toxoplasmosis in a nomadic community in Iran 51 sporulated oocysts with food, water, or and Gachsaran regions and they migrate in vegetables (9-11). Transmission through mid-spring to moderate and cool locations the placenta during pregnancy is another of Boyer-Ahmad areas to find pasture for important route of infection (11). their livestock. Their job is mainly ranching The rate of positivity to toxoplasmosis and their feeding is mainly based on milk, varies from less than 30 to more than 40 % yogurt, eggs, and meat. in the human population living in different areas of the world depending on geographical Sampling locations, climate, or people lifestyle (1-3, Criteria for selecting the subjects was a 13, 14). Food and cultural habits can play convenience sample, namely the nomads an important role in the prevalence of this who agreed to participate in the study. The infection in different communities (1, 2, 5, sample size was estimated based on the size 11, 12). of the nomadic population inhabiting the Several systematic reviews reported a study area. A sample of 5 mL of blood was prevalence rate of 43% in pregnant women, obtained from each participant and sera were 33% in healthy blood donors, 51.01% in collected from the fresh whole blood. While immunocompromised patients and 39.3% maintaining of the cold chain, sera samples in the general population for toxoplasmosis were transferred from the field area to the in Iran (1, 4, 13, 15). immunoparasitology laboratory at Shiraz Little is known about the seroprevalence University of Medical Sciences (SUMS). rate of toxoplasmosis among the nomadic The sera samples were stored at -20°C until communities as these communities have use. All participants filled a questionnaire - different food and life styles. The rate of before collecting the blood sample - which Toxoplasma infection in nomadic populations provided information about their age, sex, in southern Iran was reported to be 12.3% residence area, level of education etc. Ethical (16). A prevalence rate of 38.1% and 28% approval of the study was given by the ethics have been reported for toxoplasmosis among Committee of SUMS and informed consent nomadic communities in Somalia and was obtained from the participants or their Scotland, respectively (17, 18). guardians, in the case of children, to donate The current cross-sectional study aimed blood samples voluntarily. to assess the seroprevalence of toxoplasmosis among the nomadic population of Boyer- Serological testing Ahmad County, in Southwestern Iran. Sera samples were assessed for anti-T. gondii IgG and IgM antibodies by ELISA method, using a commercial kit (Acon Materials and Methods Biotech, Hangzhou, China), based on the manufacturer’s instructions. Index value Study population was calculated for both IgG and IgM tests. This cross-sectional study was performed Positive results were considered when index from May to September 2016 on a nomadic value was greater than 1.1. An index value of population living in Boyer-Ahmad Township 0.9 to 1.1 was considered as equivocal range in Kohgiluyeh and Boyer-Ahmad province, and negative results were defined as index in the southwest of Iran. The township of values of less than 0.9. Boyer-Ahmad is located in the cool area of the Province in a mountainous region with Statistical analysis an average of 2,200 m/asl. In autumn and The statistical analysis was performed winter seasons, nomads live in the Dehdasht using SPSS 18 software. Significance levels 52 N. Arefkhah et al. Table 1 - Demographic characteristics and prevalence of toxoplasmosis seropositivity among nomad populations in Southwest Iran Characteristics Frequency Percen IgG-positive P value (No.) (%) (%) Gender 0.868 Male 227 22.6 40 (17.6%) Female 778 77.4 134 (17.2%) Age group 0.786 1-10 19 1.9 1 (5.3%) 11-20 60 6.1 9 (15%) 21-30 245 25.1 43 (17.6%) 31-40 211 21.6 36 (17.1%) 41-50 153 15.6 31 (20.3%) 51-60 146 14.9 26 (17.8%) ≥60 144 14.7 27 (18.8%) Residence area 0.149 Urban 30 3.1 6 (20.0%) Malashora 22 2.3 4 (18.2%) Dashtroom 168 17.2 23 (13.7%) Zilaei 121 12.4 20 (16.5%) Kakan 16 1.6 3 (18.8%) Bardpahn 79 8.1 11 (13.9%) Mooshmi olya 35 3.6 10 (28.6%) Mooshmi vosta 141 14.4 22 (15.6%) Mooshmi sofla 174 17.8 37 (21.3%) Lalemina 30 3.1 11 (36.7%) Margoon 121 12.4 21 (17.4%) Javekar 40 4.1 5 (12.5%) Educational level 0.811 Illiterate 440 45.0 72 (16.4%) Elementary 227 23.2 45 (19.8%) Secondary level 173 17.7 30 (17.3%) High school diploma 89 9.1 16 (18.0%) University level 48 4.9 10 (20.8%) less than 0.05 were considered statistically participant was 41 (±17) years. The most significant. Descriptive statistics were represented age group (24.4%) was 21-30 used to describe the frequency of the data years, and the least (1.9%) was 1-10 years. and chi-squared test was used to find out The majority of participants (778 or 77.4%) the association between seroprevalence of were female while 227 (22.6%) were male. toxoplasmosis and qualitative variables. Seroprevalence of anti-T. gondii antibodies Out of the 1,005 subjects who participated Results in the study, 174 (17.3%) were seropositive for anti-T. gondii IgG antibodies, whereas A total of 1,005 subjects in nomadic tribes only 1 case (0.01%) was seropositive for IgM of Boyer-Ahmad County were enrolled in antibodies, but not for IgG antibodies. Table this cross-sectional study. Mean age of the 1 shows the distribution of the demographic Toxoplasmosis in a nomadic community in Iran 53 characteristics and of the seroprevalence of with seropositivity to T. gondii infection. Toxoplasma infection among the nomadic The majority of individuals in this study population in this study. had a low level of education and this may Anti-T. gondii antibodies were detected in be the reason that no association was found 134 (17.2%) females and 40 (17.7%) males, between educational level and seropositivity respectively. The differences between males to toxoplasmosis. Moreover, in nomadic and females were not statistically significant populations, males and females have similar (p>0.5). Moreover, no significant association everyday activities and also exposure to the was found between the educational levels possible contaminated environment. of the subjects and seropositivity to T. Although nomads have usually minimal gondii infection. The highest rate of contact with cats due to their lifestyle, seropositivity (20.3%) was seen in the yet other factors including eating raw age group 41-50 years. However, there and undercooked meat, consumption of were no significant differences (p>0.05) of contaminated water, fruits and vegetables Toxoplasma seropositivity between the age may be accounted for seropositivity to groups.