seyyed ali shariatzadeh

Intestinal helminth parasites in dogs, especially zoonotic parasites, are one of the health and economic problems of developing countries, including Iran. Toxocara canis is one of the zoonotic helminth parasites that causes serious damage to human health. According to the close relationship that humans have with dogs today, it is necessary to investigate worm parasites in these animals. The present study was conducted to investigate the prevalence of intestinal helminth parasites in urban and domestic stray dogs with two modified methods of sedimentation and flotation in the central part of Mazandaran province.

The study was carried out in three regions of Mazandaran province (Sari, Qaemshahr, and Babolsar) in 2022. We examined fecal samples from 110 dogs, comprising 78 stray dogs and 32 home dogs, to determine the presence of intestinal helminth parasites. We utilized a customized concentrates technique that incorporated flotation and sedimentation. 4 cc of 10% formalin was added to the sample container for sampling. Stool samples weighing approximately 50 to 100 grams were collected using an applicator and transferred into labeled containers. In the flotation and sedimentation method, a sufficient amount of stool sample was poured into the test tube, and then 7 cc of physiological serum was added to it. After the sample is completely dissolved by the applicator, the solution is filtered to remove excess material and transferred to a new tube. The obtained solution is centrifuged at 1000 rpm for 3-5 minutes, then the upper liquid is separated. 7 cc of saturated zinc sulfate solution was added to it and centrifuged again at 1000 rpm for 2 minutes. The resulting sediment was examined with a light microscope with X10 and X40 magnification to identify parasite contamination. Traps were set in the shelters of stray dogs to collect feces samples directly from their rectums. Labeled containers with preservatives (10% formalin) were distributed to clinics and dog owners for collecting samples from domestic dogs. A questionnaire was designed to assess the gender and age of domestic dogs based on dental characteristics, location of residence, deworming practices, and knowledge of zoonotic intestinal parasite diseases in dogs among their owners. The experiment was conducted at Mazandaran University of Medical Sciences and was approved by the Animal Ethics Committee under the reference number IR.MAZUMS.REC.1400.528.

Results indicated that 44 samples (40%) were contaminated with parasites, while 66 samples (60%) were free of worm infestation. The infected samples harbored parasite eggs including Hookworms, Toxocara, Taenia, and Dipylidium. The study found no significant difference in the distribution of helminth parasite infection among the three sampling areas in terms of the frequency of infected dogs. Further research in the field of parasite epidemiology and expanding the study to include more areas may help address this issue.

The research findings suggest that stray dogs are more significant in transmitting pollutants than domestic dogs. Urban stray dogs pose a potential public health danger because they are released post-treatment. Controlling and gathering these animals is crucial in managing parasite diseases that can be passed on to humans.

Antimalarial drug resistance is one of the key challenges that the governments face in the fight against malaria. Molecular surveillance of antimalarial drug resistance supports early detection of how the recommended treatments work. This allows immediate action to reduce any threat and prevent it from spreading. Therefore, the aim of this study was to evaluate the frequency of dihydrofolate reductase (dhfr) mutants in Plasmodium falciparum resistance to primethamine in Iranian malaria patients.

In 2020, 27 patients (21 males and 5 females) with imported P. falciparum cases were studied. The Nested-PCR technique first confirmed the species identity for all samples and then amplified by the Semi-Nested-PCR method in order to detection of single nucleotide polymorphisms (SNPs) in dhfr gene related to pyrimethamine resistance.

All samples in the 18S rRNA gene had species-specific bands for P. falciparum strains. In the sequence analysis of pfdhfr gene amplification after comparison with the standard strain (wild type), 21 patients had a double mutation (C59R+S108N) and 6 patients had a triple mutation (N51I+ C59R+S108N) of pyrimethamine resistance.

The results of this study showed that the susceptibility of P. falciparum to pyrimethamine in the treatment of malaria is significantly reducing. These findings have raised concerns about pyrimethamine resistance in P. falciparum. Due to the high emergence of double and triple mutants related to pyrimethamine resistance, the malaria surveillance and treatment systems in the region should pay more attention to the use of pyrimethamine.

Camel breeding is common in East of Iran due to its semi-arid climate and desert conditions. It transmits some diseases to other ruminants and humans due to carrying common blood parasites between humans and animals. This work aimed at studying the presence of Trypanosoma and Piroplasmida (Babesia and Theileria) species in camels in South Khorasan province using parasitological and molecular methods.

In this study, blood samples were taken from 200 camels in South Khorasan that were randomly selected in 2020. Then, thick and thin smear were prepared from the samples and stained with Giemsa staining technique and examined under a light microscope. For molecular detection of Trypanosoma, Theileria and Babesia, specific primers of each genus were used.

Microscopic examination showed that out of 200 blood samples, 8 samples (4%) were infected with Trypanosoma and no samples were infected with Theileria and Babesia. According to molecular experiments, six samples (3%) had DNA of Trypanosoma evansi and five samples (2.5%) were found with Trypanosoma brucei DNA. But the DNA of Theileria and Babesia were not observed. Phylogenetic analysis showed that the sample isolated in the present study had a high genetic affinity with genotype A of Trypanosoma evansi.

To the best of our knowledge, this was the first study to investigate the prevalence of Surra in South Khorasan province. The presence of Trypanosoma in the blood of camels in this region signifies the need for a careful monitoring system and evaluation studies as a prerequisite for controlling blood parasitic diseases in camels in South Khorasan.