A systematic review and meta-analysis on prevalence of gastrointestinal helminthic infections in rodents of Iran: An emphasis on zoonotic aspects.

Rodents are the largest group of mammals that adapt to different ecosystems and may act as the potential reservoirs of significant pathogens including gastrointestinal (GI) helminths. Rodent-borne parasitic pathogens have been and remain a great concern for animal and human health. The aim of this systematic review and meta-analysis is thus to clarify and better understand the pooled prevalence of GI helminthic infections and the associated risk factors in rodents in Iran. Multiple databases (PubMed, Scopus, Web of Science, Google Scholar, SID, Magiran and Irandoc) were searched for relevant literature published up to March 2022. A random-effects meta-analysis model was applied to estimate the pooled prevalence with 95 % confidence interval. Moreover, heterogeneity among studies was evaluated using the Cochran's Q test and the I 2-statistic. Out of the 5438 publications searched, 28 articles (30 datasets) were ultimately eligible for inclusion in the study. Thus, 3649 captured rodents belonging to 6 families, 20 genera, and 35 species were examined for GI helminths in Iran. Then, 54 helminth species were identified in the present research, including 33 nematodes, 16 cestodes, 4 trematods, and 1 acanthocephalan. The prevalence rate of GI parasitic infections was 56 % (95 % CI: 50-63 %). Hymenolepis diminuta, Syphacia obvelata and Rodentolepis nana were the most common helminthic infections (13 %, 9 %, and 8 %, respectively). Moreover, 11 potential zoonotic helminths were found. There was no significant difference in pooled prevalence between male and female rodents (P = 0.40). Considering geographical areas, northern and eastern provinces had the highest prevalence of GI helminthic infections among rodents. The prevalence of GI worms in Iranian rodents was as high as 56 % with 11 zoonotic helminths. Therefore, it is suggested to observe the health of the environment, destroy the biological nests of rodents, avoid half-finished constructions, repair and improve streams and sidewalks, organize and collect garbage, and carry out biological and chemical control to handle the population of rodents. Increasing the awareness of local people about the harmful effects of rodents and the ways of transmission and prevention of rodent-borne intestinal worms transmitted to humans should be prioritized in health decisions.

Comment on Islam et al. Helminth Parasites among Rodents in the Middle East Countries: A Systematic Review and Meta-Analysis. Animals 2020, 10, 2342.

I read with great interest the article by Islam et al. entitled "Helminth parasites among rodents in the Middle East countries: a systematic review and meta-analysis" published in Animals in December 2020 [...].

Global prevalence of Neospora caninum in rodents: A systematic review and meta-analysis.

BACKGROUND: Neosporosis has been considered a cause of abortion in dairy and beef cattle worldwide. Rodents are reservoir hosts for several infectious diseases. It is necessary to determine the prevalence of Neospora caninum in rodents to improve the current understanding of the transmission dynamics of Neospora as well as its life cycle and risk of transmission to livestock. Therefore, the objective of the present study was to estimate the pooled global prevalence of N. caninum in different rodent species. METHODS: Published studies on the prevalence of N. caninum in different rodent species were searched in the MEDLINE/PubMed, ScienceDirect, Web of Science, Scopus and Google Scholar and the reference lists of the retrieved articles until July 30, 2022. The eligible studies were selected using inclusion and exclusion criteria. The extracted data were verified and analysed using the random-effect meta-analysis. RESULT: For this meta-analysis, a total of 4372 rodents from 26 eligible studies were included. The global prevalence of N. caninum in rodents was estimated at 5% (95% CI 2%-9%), with the highest prevalence in Asia (12%; 95% CI 6%-24%) and lowest prevalence in America (3%; 95% CI 1%-14%) and Europe (3%; 95% CI 1%-6%). N. caninum was more prevalent in females (4%; 95% CI 2%-9%) than in males (3%; 95% CI 1%-11%). The most common diagnostic test was polymerase chain reaction (PCR) (21 studies). The pooled prevalence of N. caninum in rodents based on the diagnostic method was as follows: immunohistochemistry: 11% (95% CI 6%-20%), NAT: 5% (95% CI 4%-7%), IFAT: 5% (95% CI 2%-13%) and PCR: 3% (95% CI 1%-9%). CONCLUSION: The results of this study showed a relatively low but widespread prevalence of N. caninum infection in rodents.

Systematic Review and Meta-analysis of Role of Felids as Intermediate Hosts in the Life Cycle of Neospora caninum Based on Serological Data.

PURPOSE: Neosporosis is an important widespread parasitic infection caused by N. caninum. It infects a wide range of warm-blooded animals as intermediate hosts and dogs as the definitive host. Nevertheless, there are a number of questions regarding the life cycle and epidemiological aspects of N. caninum. Also, the role of felids (domestic and non-domestic) in the life cycle of N. caninum has been little described. Therefore, this study was conducted to evaluate the global prevalence of N. caninum in domestic and wild felids. METHODS: PubMed, Scopus, Google Scholar, Web of Science, and ScienceDirect databases were searched for articles published on the prevalence of N. caninum in felids until Aprill 2, 2022 and the reference lists of retrieved articles were screened. A random-effects meta-analysis model was used to estimate the pooled prevalence and 95% confidence interval. Heterogeneity among studies was evaluated using Cochran's Q and the I2 statistic. RESULTS: After exclusion of irrelevant articles and duplication removal, 30 studies were eligible for quantitative analysis including 20 studies on domestic cats and 10 studies on wild felids. The overall prevalence of neosporosis infection in cats was 15% (95% CI 10-21%) that was significantly higher in wild felids (26%, 95% CI 13-38%) than in domestic cats (11%, 95% CI 6-16%) (P = 0.03). There was no significant difference in pooled prevalence between male and female domestic cats (P = 0.75). Regarding continent, the lowest prevalence of neosporosis infection was in Asia (9%, 95% CI 1-20%) and the highest was in North America (43.6%, 95% CI 33.9-53.2%) and Africa (18%, 95% CI 9-46%). Higher prevalence was obtained when using the NAT with 22% (95% CI 7-37%), compared to the IFAT (17%, 95% CI 9-24%) and ELISA (6%, 95% CI 2-9%) (P = 0.01). CONCLUSION: The findings highlighted the importance of felids as potential intermediate hosts of neosporosis despite the fact that the source of the parasite for these animals was unknown. Further studies should be performed to investigate the role of this top predator (felids) in maintaining both domestic and sylvatic cycles of Neospora caninum.

Assessment of genetic markers for multilocus sequence typing (MLST) of Fasciola isolates from Iran.

BACKGROUND: Several markers have been described to characterise the population structure and genetic diversity of Fasciola species (Fasciola hepatica (F. hepatica) and Fasciola gigantica (F. gigantica). However, sequence analysis of a single genomic locus cannot provide sufficient resolution for the genetic diversity of the Fasciola parasite whose genomes are ∼1.3 GB in size. OBJECTIVES: To gain a better understanding of the gene diversity of Fasciola isolates from western Iran and to identify the most informative markers as candidates for epidemiological studies, five housekeeping genes were evaluated using a multilocus sequence typing (MLST) approach. METHODS: MLST analysis was developed based on five genes (ND1, Pepck, Pold, Cyt b and HSP70) after genomic DNA extraction, amplification and sequencing. Nucleotide diversity and phylogeny analysis were conducted on both concatenated MLST loci and each individual locus. A median joining haplotype network was created to examine the haplotypes relationship among Fasciola isolates. RESULTS: Thirty-three Fasciola isolates (19 F. hepatica and 14 F. gigantica) were included in the study. A total of 2971 bp was analysed for each isolate and 31 sequence types (STs) were identified among the 33 isolates (19 for F. hepatica and 14 for F. gigantica isolates). The STs produced 44 and 42 polymorphic sites and 17 and 14 haplotypes for F. hepatica and F. gigantica, respectively. Haplotype diversity was 0.982 ± 0.026 and 1.000 ± 0.027 and nucleotide diversity was 0.00200 and 0.00353 ± 0.00088 for F. hepatica and F. gigantica, respectively. There was a high degree of genetic diversity with a Simpson's index of diversity of 0.98 and 1 for F. hepatica and F. gigantica, respectively. While HSP70 and Pold haplotypes from Fasciola species were separated by one to three mutational steps, the haplotype networks of ND1 and Cyt b were more complex and numerous mutational steps were found, likely due to recombination. CONCLUSIONS: Although HSP70 and Pold genes from F. gigantica were invariant over the entire region of sequence coverage, MLST was useful for investigating the phylogenetic relationship of Fasciola species. The present study also provided insight into markers more suitable for phylogenetic studies and the genetic structure of Fasciola parasites.

A brief review of malaria epidemiological trend in Kermanshah province, Iran, 1986-2014.

Malaria is the most severe protozoan disease in the world. As a result of strict malaria control programs, malaria's epidemiological model has changed. Knowing this epidemiological model and its effects will help us predict and prevent a new epidemic. This research was conducted to review the epidemiological trend of malaria in the Kermanshah province of Iran and some of its effective factors. Data were extracted from the registers in the disease control unit of the province, national population census, and annual rainfall report. The data was processed by SPSS16. There has been an evident decrease in malaria cases over the last 30 years in Kermanshah. This decreasing trend began especially after 1994, and since then, just 6% of all cases have happened. Between 1990 to 1997, an epidemic occurred, and more than 80% of positive cases were registered in these years. P. vivax malaria was the most common type (99.32%), and P. falciparum malaria was the second, with a very egregious difference (0.68%). The average age was 23.1 years, and men were infected twice more than women. There was a positive relation between annual rainfall level and positive malaria cases in these cities. After the major changes in malaria control programs in Kermanshah province, the number of positive cases fell noticeably, and now it is in the elimination stage. All cases of malaria were imported in the last years, and no resistance type was ever seen.

Serological Survey of Neospora caninum and Toxoplasma gondii Co-Infection in Rodents in Northwestern Iran.

BACKGROUND: Our knowledge of the epidemiology of rodents' parasitic agents in Iran is scarce, although some of these pathogens play an important role in human and veterinary medicine, such as Toxoplasma gondii and Neospora caninum. The purpose of this study was to determine the seroprevalence of Toxoplasma gondii and Neospora caninum in rodents of northwestern Iran between Mar and Dec 2015. METHODS: Overall, 157 serum samples from rodents (101 Meriones persicus, 41 Mus musculus, and 15 Cricetulus migratorius) were assayed by the indirect fluorescence antibody test (IFAT) for antibodies to T. gondii and N. caninum. RESULTS: We found a prevalence of 20.38% (32/157) for N. caninum, 35% (55/157) for T. gondii. Co-presence of antibodies to N. caninum and T. gondii was found in 10 (6.36%) rodents. A significant association was found between the rodents species and seropositivity to N. caninum (P<0.05) but there was no association with rodents species for T. gondii. The overall prevalence of the aforementioned parasites was higher in male versus female rodents. CONCLUSION: The high seroprevalence of toxoplasmosis and neosporosis in rodents in the study area has implications for translocation of these infections across wider geographical regions since these rodents are mostly preyed on by cats or dogs; hence, which can transfer the parasite to other hosts.

Pneumocystis jirovecii Pneumonia and Human Immunodeficiency Virus Co-Infection in Western Iran.

BACKGROUND: The human immunodeficiency virus (HIV) is one of the greatest health challenges facing worldwide. The virus suppresses the immune system of the patient. The purpose of this study was to describe the epidemiology of Pneumocystis jirovecii colonization, rarely found in normal people, in patients with stage 4 HIV infection in Kermanshah, Iran, from Mar 1995 to Feb 2016. METHODS: In this retrospective study, we surveyed medical records of stage 4 HIV-positive patients with Pneumocystis admitted to Behavioral Counseling Center of Kermanshah. Several parameters were analyzed including demographic characteristics, body mass index (BMI), treatment regimen, diagnostic methods, presenting signs and symptoms, presence of co-pathogens (bacteria, viruses, or fungi), and nadir of CD4 T-cell count before and after treatment. RESULTS: During the study period, 114 HIV-positive patients were analyzed, of whom 93 were male and 21 were female, respectively. Of 114 cases, 26 (22.8%) patients had Pneumocystis. All 26 colonized patients had CD4 cell counts below 200 cells/mm3 (range 9-186). The median CD4 count increased from 91 cells/mm3 pre-trimethoprim/sulfamethoxazole (TMP/SMX) to an estimated 263 cells/mm3 after starting (TMP/SMX). BMI was normal in the majority of the patients (85%) and coughs, sputum, and chest pain (19; 73%) followed by dyspnea, weakness, and lethargy (7; 27%) were the most common presentations of fungal pneumonia. CONCLUSION: HIV/AIDS-infected patients are an environmental reservoir of P. jirovecii infection that might transmit the infection from one person to another via the airborne route. In addition, rapid identification of such individuals may reduce the morbidity and mortality rate of this disease.

Epidemiology of Fascioliasis in Kermanshah Province, Western Iran.

BACKGROUND: We aimed to determine the prevalence of fasciolosis in the definitive hosts (human and livestock) and intermediate (Lymnaea snails) hosts in Kermanshah Province, western Iran from 2014-2016. METHODS: The study on animals was descriptive and retrospective one. All daily records of animals slaughtered in the abattoirs were analyzed. For the study of human fascioliasis, 975 serum samples were collected from different parts of Kermanshah Province and analyzed using ELISA based on excretory-secretory antigens. Moreover, 4400 Lymnaea snails were collected from 25 habitats. The snails were identified and examined for presence of cercariae by shedding method. RESULTS: Fasciolosis was diagnosed in 1.7% of slaughtered animals, which was significantly greater than the other species (P<0.005). There was significant difference (P<0.001) between the prevalence of fasciolosis and seasonal pattern. As for human cases, five cases (0.5%) were positive for fascioliasis. Regarding the seropositivity to fasciolosis, no significant differences were found for age groups, sex, level of education and occupation. No Fasciola infection was seen in snails of the family Lymnaeidae. CONCLUSION: The prevalence of Fasciola parasite was lower compared to other provinces. This is probably due to sequential decline in rainfall and hot climate that makes conditions difficult for the snail intermediate host snails and the larval stages of fasciolid trematodes. The habitual food of people is another important point.

Gene cassettes of class I integron-associated with antimicrobial resistance in isolates of Citrobacter spp. with multidrug resistance.

BACKGROUND AND OBJECTIVES: Integrons play a major role in the transmission and accumulation of resistance factors in multidrug resistant bacteria. This study was aimed to evaluate the gene cassettes of class I integron and antimicrobial resistance in isolates of Citrobacter with multidrug resistance (MDR). MATERIALS AND METHODS: Ninety isolates of Citrobacter spp. were collected from the largest hospital in Kermanshah, Iran. Antimicrobial resistance patterns were determined using disc diffusion method. The class I integron were detected by PCR. The integrase positive isolates were further analyzed for the presence of gene cassettes using 5' and 3' conserved sequences (CSs) primers and PCR products were sequenced. The data were analyzed using the chi-square test. RESULTS: Of 90 Citrobacter isolates, 46 (51.1%) were multidrug resistant. Class I integron and gene cassettes were determined in 30 isolates (65.2%). Gene cassettes were found which contained genes encoded resistance to aminoglycosides and trimethoprim and a putative gene. Gene cassettes of dfrA12-orfF-aadA2, dfrA1-aadA1, aadA1 and dfrA15-aadA2 were also found in Citrobacter isolates. CONCLUSION: Our results indicate there is a high frequency of class I integron among multi-drug resistant strains of Citrobacter isolated from clinical settings. A high frequency of class I integron associated gene cassettes, in particular dfr and aadA, present in MDR strains of Citrobacter. This data indicates an important role of integrons in the creation and transmission of MDR strains in health care centers.

Cutaneous leishmaniasis in Qasr-e Shirin, a border area in the west of Iran.

AIM: The prevalence of cutaneous leishmaniasis (CL) is growing in Iran, and new sources of the disease have been found in the country. The purpose of this study was to describe the epidemiology of CL in Qasr-e Shirin County, Kermanshah Province, West of Iran. Qasr-e Shirin is located near the Iran-Iraq border, and several million pilgrims pass through this area to Iraq every year. MATERIALS AND METHODS: A descriptive cross-sectional study was carried out for active case detection from April 1, 2014, to March 31, 2015. All individuals with suspicious lesions were identified through house-to-house visits in the aforementioned area. A questionnaire was filled out for everyone with clinical suspicion of CL. A diagnosis was made based on parasitological examination of the lesion exudate. The annual incidence and prevalence of CL were estimated. RESULTS: In total, 5277 individuals were randomly screened for the presence of active lesions or scars suspected of CL. The overall prevalence of CL in the County was 4.8% (60 cases had active lesions and 194 cases had scars). All age groups were affected, but the highest incidence of CL was seen in the age group 20-29 years (1.9%). The incidence and prevalence were higher in women than men (5.5% vs. 4%). Most cases (45.6%) had a single lesion or scar and 44 (17.4%) patients had five or more lesions or scars. CONCLUSION: The incidence of CL in Qasr-e Shirin County is high. There is a need for further studies on reservoirs and vectors of leishmaniasis in this area. The results of such studies help to perform more efficient and timely spraying against phlebotomine sandfly or detect and decrease the animal reservoir population.

Trend of cutaneous leishmaniasis in kermanshah province, west of iran from 1990 to 2012.

BACKGROUND: This study was conducted to explain the trend of Cutaneous Leishmaniasis (CL) in Kermanshah Province, western Iran from 1991-2012. METHODS: In this analytical-descriptive study, all of the patients suspected to CL in Kermanshah Province were studied. Smears were prepared from most of them, stained with Giemsa, and examined microscopically for Leishman bodies. A few of the patients were diagnosed according to physician diagnosis and response to glucantime. Questionnaires were completed for all of them. Collected data were analyzed using SPSS-21 and Spearman and Kendall tests. RESULTS: From 1991 to 2012, 1684 cases of CL were recorded. In the years 2011-12 the frequency of CL in the province reached to 7.4/100,000, which showed a remarkable increase in the frequency of new cases CL in the province. In the years 2011-12 about 47% of total cases of CL in the province, was seen in Ghasr-e-Shirin district,which the frequency of CL in this district reached to 264.5/100,000. Frequency of CL in males and females was 57% and 43% respectively. The most cases of CL were seen in housewives (32.1%) and age groups of 20 to 29 years old (19.9%). In addition, the most cases of disease were seen in winter (41.8%) and fall (28.9%). CONCLUSION: CL is increasing remarkably in warm climates of the province, and Ghasr-e-Shirin must be of particular interest, as the most infected district in the province.

The opioid antagonist naloxone inhibits Leishmania major infection in BALB/c mice.

BALB/c mice are susceptible to develop non-healing, progressive infection with Leishmania major (L. major) due to the development of a non-protective Th2 response. Resistance to L. major infection is dependent to Th1 response. Treatment of mice with the opioid antagonist naloxone can promote the activation of Th1 responses. Here we study the effect of chronic administration of various doses of naloxone on susceptibility of BALB/c mice to L. major infection. Our results showed that naloxone has dose-dependent biphasic effect on L. major infection in BALB/c mice. While administration of 1mg/kg × 2/day tends to exacerbate the local reaction to L. major infection, treatment with 10mg/kg × 2/day of naloxone suppresses the local reaction and progress of infection. On the other hand treatment of mice with middle dose (5mg/kg whether 1 or 2 times per day) does not have significant effect on the infection. This study demonstrates that administration of high dose of naloxone could improve protection against L. major infection in BALB/c mice, presumably by modulation in Th1/Th2 balance or by affecting macrophages through binding to Toll-like receptors.

Epidemiological aspects of canine visceral leishmaniosis in the Islamic Republic of Iran.

An epidemiological study to examine the sero-prevalence of zoonotic visceral leishmaniosis (ZVL) among domestic and wild canines in endemic foci of Iran was carried out during 1999-2003 to assess the distribution of the disease and the possible association between infection in dogs, wild canines and people. Anti-leishmanial antibodies were detected by the direct agglutination test (DAT). Parasitological study was performed for all captured wild canines and were detected in some of the seropositive dogs with specific clinical signs (n=107). Serum samples (n=1568) were collected from domestic dogs in villages that are known endemic foci of human visceral leishmaniosis (HVL). Wild canine sera were collected from jackals (Canis aureus, n=10), foxes (Vulpes vulpes, n=10) and wolves (Canis lupus, n=10). Of the 1568 serum sampled collected from domestic dogs, 222 (14.2%) were positive by DAT (1:320 and above). No statistically significant difference was found between male (15.2%) and female (11.8%) sero-prevalence (P=0.083). Dogs of 8 years and above showed the highest sero-prevalence (40.6%). Only 23.9% of the seropositive domestic dogs had clinical signs. Parasitology and serology tests that were performed in 30 wild canines showed 10% these animals were infected by Leishmania infantum. Ten out of 11 Leishmania spp. isolated from the dogs and wild canines were identified as L. infantum and one other as L. tropica by molecular and biochemical techniques. For the first time in Iran, L. infantum and L. tropica were isolated from viscera of both a wolf and a domestic dog.