OBJECTIVE: To analyze the quality of blood smear examinations for malaria parasites in Chenzhou City, so as to provide insights into sustainable consolidation of malaria elimination achievements. METHODS: All positive blood smears from fever patients were irregularly sampled from each county (district) of Chenzhou City from 2018 to 2022 and reexamined, and no less than 3% negative blood smears were reexamined. The preparation, dyeing, cleanliness and microscopic examination results of blood smear were reexamined, and the quality of blood smear reexaminations was assessed using a descriptive statistical method. RESULTS: A total of 13 625 fever patients received blood smear examinations for malaria parasites in Chenzhou City from 2018 to 2022, of which 21 were positive and 13 604 were negative; 687 blood samples were reviewed, and the percentage of negative blood smear reexaminations was 4.90% (666/13 604), with a 63.51% rate of qualified negative blood smears preparation, a 67.87% rate of qualified dyeing and a 76.13% rate of qualified cleanliness, and no missing diagnosis found. There were 21 positive blood smears reexamined, and the proportions of qualified blood smears preparation, dyeing and cleanliness were all 85.71%, with 2 smears mistaking Plasmodium species (9.52%). The percentage of qualified negative blood smears preparation was 51.41% in 2022, which reduced by 31.61% in relative to that (75.17%) in 2019 (χ² = 9.033, P < 0.05), and the percentage of qualified negative blood smears dyeing was 60.19% in 2022, which reduced by 28.82% in relative to that (84.56%) in 2019 (χ² = 19.498, P < 0.05), while the percentage of qualified negative blood smears cleanliness was 62.96% in 2022, which reduced by 28.93% in relative to that (88.59%) in 2019 (χ² = 23.826, P < 0.001). In addition, there were no significant differences in the proportion of qualified negative blood smears preparation (χ² = 0.260, P > 0.05) or dyeing (χ² = 1.094, P > 0.05) among the three years, while a significant difference was detected in the percentage of qualified negative blood smears cleanliness (χ² = 12.175, P < 0.05). CONCLUSIONS No missing diagnosis was seen in blood smear examinations for malaria parasites among fever patients in Chenzhou City after malaria elimination; however, there were reductions in proportions of qualified blood smears preparation, dyeing and cleanliness. Quality control of blood smear examinations is recommended to be reinforced in key regions of Chenzhou City.
Animals ; Humans ; Parasites ; Malaria/prevention & control* ; Plasmodium ; Fever ; Microscopy

Parasite-derived non-coding RNAs (ncRNAs) not only contribute to life activities of parasites, and microRNA (miRNA), long non-coding RNA (lncRNA), and circular RNA (circRNA) may generate a competitive endogenous RNA (ceRNA) regulatory network with host miRNAs and mRNAs via extracellular vesicles, thereby participating in infection and pathogenic processes. This article presents an overview of characterizing ncRNAs derived from parasites and the cross-species regulatory role of parasite-derived ncRNAs in host gene expression and its underlying mechanisms.
Animals ; Parasites ; Gene Regulatory Networks ; MicroRNAs/metabolism* ; RNA, Messenger/genetics* ; RNA, Circular/genetics* ; RNA, Competitive Endogenous

Introduction: Dioctophyma renale, also known as the “giant kidney” worm is the largest nematode that infects mammals. Most commonly, it infects dogs and only a few cases of human infestation have been reported. Case Presentation: In this case, we present a 71-year-old male with a history of right flank pain, painless hematuria, obstructive urinary symptoms and occasional passage of a long red meat-like structure via urethra. Previous ultrasonography revealed a renal mass that was interpreted as renal malignancy. Patient was advised radical nephrectomy with biopsy; however, he was lost to follow up. After 8 years, he again presented with a 2-month history of right flank pain, gross hematuria, unintentional weight loss and obstructive urinary symptoms. He was admitted to our institution and laboratory findings revealed microcytic hypochromic anemia. Ultrasound showed a focal bulge in the superior wall of the urinary bladder and an enlarged right kidney with a large heterogeneous solid structure. Insertion of a foley catheter relieved the urinary obstruction and there was noted passage of a single roundworm measuring 55 cm by 0.32 cm. The specimen was sent for histopathology and microscopic examination revealed a necrotic body of a roundworm consistent with Dioctophyma renale. Case Discussion The clinical manifestations of D. renale infection are non-specific and the diagnosis can be a challenge as it commonly mimics renal malignancy and other intra-abdominal tumors. The diagnosis is often an incidental finding of the parasite on necropsy or by finding ova in the urine. The clinical findings of painless hematuria, unintentional weight loss and an ultrasound finding of renal mass usually point toward the diagnosis of renal cell carcinoma. As we present this case, it will be highlighted that such signs and symptoms, such as painless hematuria, unintentional weight loss and ultrasound finding of a renal mass, can also be found in patients with rare human parasitism from Dioctophyma renale.
Parasites ; Dioctophymatoidea ; Carcinoma ; Kidney

Hydatid disease is a zoonotic infection in humans. The disease is endemic in some parts of the world, including Africa, Australia, and Asia, where cattle grazing is common; the disease is spread by an enteric route following the consumption of food contaminated with the eggs of the parasite. Failure to identify this parasite results in delayed diagnosis and increased morbidity to the patient. Upon diagnosis, every possible step should be taken, both surgical and medical, to prevent anaphylactic reactions from the cystic fluid. Postsurgical long-term follow up along with periodical ultrasonography of the liver and computed tomography scan of the abdomen is essential to rule out possible recurrence.
Abdomen ; Africa ; Anaphylaxis ; Animals ; Asia ; Australia ; Cattle ; Delayed Diagnosis ; Diagnosis ; Echinococcosis ; Eggs ; Follow-Up Studies ; Humans ; Liver ; Ovum ; Parasites ; Recurrence ; Ultrasonography ; Zoonoses

Human echinococcosis is an infectious disease caused by tapeworms belonging to the species Echinococcus. This parasite has a worldwide distribution and is considered a neglected tropical disease by the World Health Organization. Due to the diversity of Echinococcus spp. hosts, as well as variation in geographical, climatic, and socio-ethnic conditions, the question of the strains or genotypes of Echinococcus spp. that are involved in human infections is important. The aim of this study was to provide a summary of the available data on genotypes of Echinococcus obtained from the Iranian population. Four international databases (PubMed, Scopus, Science Direct, and Web of Science) and 4 Persian databases (Magiran, Scientific Information Database, Iran Medex, and IranDoc) were searched for cross-sectional studies that reported the genotypes of Echinococcus spp. in human echinococcosis cases using molecular methods in Iran through July 2018. The Newcastle-Ottawa Scale was used to assess the quality of the selected studies. A total of 559 cases of human cystic echinococcosis were reported in the 21 included articles. The majority of cases belonged to genotype G1 (89.2%; 95% confidence interval [CI], 80.1 to 95.8), genotype G6 (8.2%; 95% CI, 2.8 to 15.9), and genotype G3 (2.3%; 95% CI, 1.1 to 3.9). Since genotype G1 of Echinococcus appears to be the most prevalent genotype affecting humans in Iran, disease control initiatives aimed at sheep intermediate hosts may be the most beneficial. In addition, educational programs and serological screening in individuals may help reduce the national impact of the disease.
Cestoda ; Communicable Diseases ; Cross-Sectional Studies ; Echinococcosis ; Echinococcus ; Genotype ; Humans ; Iran ; Mass Screening ; Parasites ; Sheep ; World Health Organization

Cutaneous leishmaniasis (CL) is most common form of leishmaniasis and is characterized by ulcerative skin lesions. The objective of this study was to conduct a systematic review and meta-analysis of clinical trials that compared the efficacy of miltefosine and glucantime for the treatment of CL. We searched the following databases: Cochrane, PubMed, Embase, Scopus, Web of Science, ProQuest, Cochrane Central Register of Controlled Trials, International Clinical Trials Registry Platform search portal of World Health Organization, Sid, Irandoc, Magiran, and clinicaltrials.gov. We used keywords including “miltefosine,” “glucantime,” and “Leishmania.” The quality of studies was assessed using the Cochrane risk of bias tool. A random-effects model was employed for the analysis. We assessed heterogeneity by the chi-square test and the I² index statistic. When heterogeneity was present, meta-regression analyses were performed. The Egger method was used to assess publication bias; when it was significant, the trim-and-fill method was used to test and adjust for publication bias. A total of 1,570 reports were identified, of which 10 studies were included in the meta-analysis. In the meta-analysis, there was no significant difference between the efficacy of miltefosine and glucantime; however, subgroup analysis showed that, regarding parasite species other than Leishmania braziliensis, miltefosine was significantly superior to glucantime (intention to treat; relative risk, 1.15; 95% confidence interval, 1.01 to 1.32). In the meta-regression, only the glucantime injection type was significant at the p=0.1 level. The Egger test found statistically significant publication bias; however, including the 3 missing studies in the trim-and-fill analysis did not change the results. This meta-analysis found that miltefosine seems to be more effective than glucantime, at least in species other than L. braziliensis, for treating CL.
Bias (Epidemiology) ; Leishmania braziliensis ; Leishmaniasis ; Leishmaniasis, Cutaneous ; Methods ; Parasites ; Population Characteristics ; Publication Bias ; Skin ; Sudden Infant Death ; Ulcer ; World Health Organization

OBJECTIVES: Blastocystis hominis is a very common large intestinal protozoan with global prevalence in humans and non-human hosts. No precise statistics exist regarding the geographical distribution of Blastocystis that would enable the identification of high-risk communities. Therefore, the current research aimed to characterize the spatial patterns and demographic factors associated with B. hominis occurrence in northern Iran.METHODS: The current study was performed among 4,788 individuals referred to health centers in Mazandaran Province, from whom stool samples were obtained. Socio-demographic data were gathered using a questionnaire. Samples were examined by a direct wet mount, the formalin-ethyl acetate concentration technique, and trichrome staining. Moran local indicators of spatial association and a geographically weighted regression model were utilized to analyze the results.RESULTS: Generally, the infection rate of Blastocystis parasites was 5.2%, and was considerably higher in the age group of 10-14 years (10.6%) than in other age groups (p=0.005). Our data showed important associations between the occurrence of B. hominis and age, residence, job, contact with domestic animals, anti-parasitic drug consumption, and elevation above sea level (p<0.001).CONCLUSIONS: The current study characterized for the first time the infection rate and risk of B. hominis in the north of Iran, and produced a prediction map. It is expected that this map will help policymakers to plan and implement preventive measures in high-risk areas and to manage already-infected patients.
Animals, Domestic ; Blastocystis hominis ; Blastocystis ; Demography ; Epidemiology ; Geographic Information Systems ; Humans ; Iran ; Parasites ; Prevalence ; Spatial Regression

The gastrointestinal tract is a vast reservoir for internal microbiota; it is exposed directly to various externally introduced microbes, including bacteria, viruses, parasites and others. In immune-compromised conditions, the gastrointestinal tract is frequently affected by infectious diseases that seldom manifest clinically in immune-competent hosts. Immune-compromised conditions result from a variety of reasons, including human immunodeficiency virus infection, anti-cancer chemo-radiotherapy, immune suppressive therapy for autoimmune diseases, and organ transplantations. The stomach is a relatively rare site for opportunistic infections in immune-compromised patients compared to the esophagus and colon, where esophagitis and colitis develop frequently and cause significant clinical consequences. Helicobacter pylori infection is majorly involved in gastric malfunctioning in immune-compromised patients, followed by cytomegalovirus infection. Infections by Cryptosporidium, Mycobacterium avium complex, histoplasmosis, leishmaniasis, aspergillosis, or treponema, have been reported; however, gastric involvement of these agents is extremely rare. This review discusses the general aspects and recent reports on gastric infection in immune-compromised patients.
Aspergillosis ; Autoimmune Diseases ; Bacteria ; Colitis ; Colon ; Communicable Diseases ; Cryptosporidium ; Cytomegalovirus Infections ; Esophagitis ; Esophagus ; Gastrointestinal Tract ; Helicobacter pylori ; Histoplasmosis ; HIV ; Humans ; Leishmaniasis ; Microbiota ; Mycobacterium avium Complex ; Opportunistic Infections ; Organ Transplantation ; Parasites ; Stomach ; Transplants ; Treponema

Anisakidosis is a term that collectively refers to a human infection caused by larvae of the family Anisakidae. Because Anisakis simplex was the main cause, it was originally called anisakiasis or anisakiosis, but since other parasites such as Pseudoterranova decipiens also cause similar diseases, the family name is now used as the diagnostic name. Anisakidosis cases have been increasing steadily owing to the propagation of the Japanese raw-fish-eating culture, such as sushi and sashimi, around the world; the traditional raw-fish-eating habits of individual countries; the establishment of marine mammal protection laws; and the development of endoscopic diagnostic techniques. The disease continues to occur in Korea, where most human parasites are believed to have been eradicated and is probably the most common parasitic disease encountered in clinical practice. Anisakidosis is a disease associated with acute abdominal pain. Anisakid larvae can invade the entire digestive tract and abdominal cavity and cause abdominal pain and a variety of digestive system symptoms. Thus, the history of eating raw fish is very important for its differential diagnosis. The lack of a precise understanding of the pathogenesis and clinical course of this disease may lead to unnecessary surgery. Anisakidosis may also manifest as allergic symptoms. Therefore, it is necessary to understand anisakidosis from the perspective of public health, food hygiene, and preventive medicine.
Abdominal Cavity ; Abdominal Pain ; Anisakiasis ; Anisakis ; Asian Continental Ancestry Group ; Diagnosis, Differential ; Digestive System ; Eating ; Food Hypersensitivity ; Gastrointestinal Tract ; Host-Parasite Interactions ; Humans ; Hygiene ; Jurisprudence ; Korea ; Larva ; Mammals ; Parasites ; Parasitic Diseases ; Preventive Medicine ; Public Health ; Raw Foods ; Unnecessary Procedures

Cathepsin D (CatD, EC 3.4.23.5) is a member belonging to the subfamily of aspartic endopeptidases, which are classified into the MEROPS clan AA, family A1. Helminth parasites express a large set of different peptidases that play pivotal roles in parasite biology and pathophysiology. However, CatD is less well known than the other classes of peptidases in terms of biochemical properties and biological functions. In this study, we identified 2 novel CatDs (CsCatD1 and CsCatD2) of Clonorchis sinensis and partially characterized their properties. Both CsCatDs represent typical enzymes sharing amino acid residues and motifs that are tightly conserved in the CatD superfamily of proteins. Both CsCatDs showed similar patterns of expression in different developmental stages of C. sinensis, but CsCatD2 was also expressed in metacercariae. CsCatD2 was mainly expressed in the intestines and eggs of C. sinensis. Sera obtained from rats experimentally infected with C. sinensis reacted with recombinant CsCatD2 beginning 2 weeks after infection and the antibody titers were gradually increased by maturation of the parasite. Structural analysis of CsCatD2 revealed a bilobed enzyme structure consisting of 2 antiparallel β-sheet domains packed against each other forming a homodimeric structure. These results suggested a plausible biological role of CsCatD2 in the nutrition and reproduction of parasite and its potential utility as a serodiagnostic antigen in clonorchiasis.
Animals ; Aspartic Acid Endopeptidases ; Biology ; Cathepsin D ; Cathepsins ; Clonorchiasis ; Clonorchis sinensis ; Eggs ; Helminths ; Humans ; Intestines ; Metacercariae ; Ovum ; Parasites ; Peptide Hydrolases ; Rats ; Reproduction