Diversity of Rickettsia species in collected ticks from Southeast Iran.

Rickettsia occurs worldwide and rickettsiosis is recognized as an emerging infection in several parts of the world. Ticks are reservoir hosts for pathogenic Rickettsia species in humans and domestic animals. Most pathogenic Rickettsia species belong to the spotted Fever Group (SFG). This study aimed to identify and diagnose tick fauna and investigate the prevalence of Rickettsia spp. in ticks collected from domestic animals and dogs in the rural regions of Kerman Province, Southeast Iran. In this study, tick species (fauna) were identified and 2100 ticks (350 pooled samples) from two genera and species including Rhipicephalus linnaei (1128) and Hyalomma deteritum (972) were tested to detect Rickettsia genus using Real-time PCR. The presence of the Rickettsia genus was observed in 24.9% (95%CI 20.28-29.52) of the pooled samples. Sequencing and phylogenetic analyses revealed the presence of Rickettsia aeschlimannii (48.98%), Rickettsia conorii israelensis (28.57%), Rickettsia sibirica (20.41%), and Rickettsia helvetica (2.04%) in the positive samples. The results showed a significant association between county variables and the following variables: tick spp. (p < 0.001), Rickettsia genus infection in ticks (p < 0.001) and Rickettsia spp. (p < 0.001). In addition, there was a significant association between tick species and host animals (dogs and domestic animals) (p < 0.001), Rickettsia spp infection in ticks (p < 0.001), and Rickettsia spp. (p < 0.001). This study indicates a high prevalence of Rickettsia spp. (SFG) in ticks of domestic animals and dogs in rural areas of Kerman Province. The health system should be informed of the possibility of rickettsiosis and the circulating species of Rickettsia in these areas.

Scanning electron microscopy of digestive tract parasites in jungle cat (Felis chaus).

Among the 10 native cats of Iran, the Felis chaus is considered as one of the largely unknown species. Despite the reports on jungle cats in southeast Iran, there is no comprehensive information about their parasitic diseases. Scanning electron microscope (SEM) provides a valuable tool for the study of these organisms. In October 2022, a 15-year-old male jungle cat (F. chaus) was examined for gastrointestinal parasites using SEM which revealed exact parasite structures such as the mouth, shape of the lips, teeth and their position, papillae, excretory pore, and amphids. SEM of the Taenia taeniaeformis found in the F. chaus intestinal epithelium revealed that this tapeworm consisted of four unarmed suckers and a large armed rostellum. The rostellum was observed bearing double rings of alternating and circular hook arrangements. There were 21 large hooks in the anterior ring and 21 slightly smaller hooks in the posterior one. This study is the first report of Joyeuxiella echinorhyncoides from a jungle cat (F. chaus) in southeastern Iran. The rostellum was cylindrical and armed with thorn shape hooks that covered the whole rostellum with similar density. It was armed with 20-30 long hooks arranged in 16 rows. Four big suckers were visible at the base of the rostellum, two on each side. The suckers were round, and unlike the rostellum, these structures were unarmed. The results of the present study observed under SEM, indicated that organs such as sucker and rostellum in cestodes and mouth and the shape of lips and teeth in nematodes played a significant role in the biology of these helminths. The SEM reveals the surface structures and their relationships which results in better distinguishing the species and showing their detailed differences. More SEM studies need to be conducted on other species of cestodes and nematodes, along with pathological tests, to obtain more comprehensive and precise information about how these parasites harm this jungle cat host. The results of present study indicate that morphological details are important which should be considered in the classification. Meanwhile, external structures described herein using SEM, further investigation using transmission electron microscope provide more data on the biology of the parasites. RESEARCH HIGHLIGHTS: Light microscopy is the first step to identify the parasites. High magnification 3D images of the SEM reveal the surface structures of parasites and their relationships precisely. SEM study of the parasites results in distinguishing the species and showing their detailed differences.

An update on spotted fever group serology in Kerman Province, Iran.

Rickettsia conorii is the causative agent of Mediterranean spotted fever (MSF) and reports of its geographical distribution are spreading every day. Recently, some cases of the MSF have been reported from Iran. However, little information is available about the MSF epidemiology in Iran. The aim of the current study was to investigate anti-R. conorii IgG seroprevalence among farmers living in the rural regions of Kerman province (in southeastern Iran). In this study, 281 blood samples were collected from farmers in Zarand and Jiroft counties and tested for detection of anti-R. conorii IgG antibodies using the ELISA method. Among the 281 samples, 14 farmers (4.98%, CI 95%; 2.45-7.55%) had anti-R. conorii IgG antibodies. Seroprevalence of MSF in Zarand and Jiroft counties were 4.58% and 5.33%, respectively. The serological evidence of this study indicates the seroprevalence of R. conorii in rural areas of the Kerman province of Iran. So, it is recommended that the Iranian health care system pay attention to the MSF.

Histopathologic and histomorphometric evaluation of Dipetalonema evansi infection in camel testicular tissue.

Camels are important sources of milk, meat, wool and leather, and are widely used in transportation in arid and semi-arid areas. But their illnesses, especially parasitic diseases, have not been taken into consideration. The Dipetalonema evansi microfilariae are in the blood. Adult nematode is only dedicated to camels and disrupts spermatic arteries, lung arteries, right atrium, and testicles. This study was carried out on testicular samples of camels infected with D. evansi referred from slaughterhouse. In each of the control and contaminated groups, 5 samples were examined. In this study, in addition to the qualitative description of parasite histopathologic lesions, the spermatogenesis process was evaluated quantitatively including spermatogenesis process, diameter of the seminiferous tubules and Johnsen ranking and compared with the control group. Histopathological examination of infected testis with D. evansi showed lumen obstruction of testicular blood vessels by parasites, hypertrophy of blood vessels, degenerative and necrosis changes in the tubules, decreased spermatogenetic activity, increased interstitial space tubules, destruction of the spermatogenic cells. Also, there was a significant difference in the control and contaminated groups in the parameters of spermatogenesis, diameter of the seminiferous tubules and Johnsen score.