Consumption of raw and semi-raw aquatic products is strongly associated with the development of fish-borne parasitic diseases. Detection of fish-borne parasites in aquatic products is of great significance for the prevention and control of fish-borne parasitic diseases. This review describes the advances in the application of etiological, molecular biological and immunological techniques alone and in combinations for detection of fish-borne parasites, so as to provide insights into detection of fish-borne parasites.
Objective: To analyze the epidemiological characteristics of visceral leishmaniasis in Gansu Province from 2017 to 2023, so as to provide insights into formulation of the visceral leishmaniasis control strategy in the province.
Methods: All epidemiological features of confirmed and clinically diagnosed cases of visceral leishmaniasis reported in Gansu Province from January 1, 2017 to December 31, 2023 were retrieved from the Chinese Disease Prevention and Control Information System, and the epidemiological characteristics of visceral leishmaniasis cases were analyzed descriptively.
Results: A total of 280 visceral leishmaniasis cases were reported in 39 counties (cities and districts) of Gansu Province from 2017 to 2023, including 258 local cases reported in 21 endemic counties (districts) and 22 imported cases reported in 18 non-endemic areas. Of the 280 cases, there were 262 cases with mountain type zoonotic visceral leishmaniasis (MT-ZVL), 12 cases with desert-type zoonotic visceral leishmaniasis (DT-ZVL), and 6 cases with unknown type. Re-emerging MT-ZVL occurred in Maiji District, Qinzhou District, Lixian County, Kangxian County, Zhenyuan County, Qin'an County and Yongjing County, and re-emerging DT-ZVL occurred in Dunhuang City, while emerging DT-ZVL occurred in Yumen City. The five counties (districts) reporting the highest number of visceral leishmaniasis cases included Wudu District, Wenxian County, Tanchang County, Zhouqu County and Diebu County, and a total of 220 cases were reported in these five counties, accounting for 78.57% of all visceral leishmaniasis cases in the province. Visceral leishmaniasis cases were reported each month throughout the year, with the peak in July. All reported visceral leishmaniasis cases had ages of 6 months to 81 years, including 50.71% (142/280) under 15 years of age, 49.29% (138/280) at ages of 15 years and older, and of all cases under 15 years of age, children at ages of 0 to 3 years were the most commonly affected (27.14%, 76/280). Among 280 visceral leishmaniasis cases, there were 173 males and 107 females with a male to female ratio of 1.62∶1, and farmer was the most common occupation (40.36%), followed by diaspora children (37.86%).
Conclusions: The prevalence of visceral leishmaniasis appeared an overall tendency towards a decline in Gansu Province from 2017 to 2023; however, there are still multiple challenges for visceral leishmaniasis control in the province. Reinforced dog monitoring and management, intensified human health education and improved capability building among professionals are recommended to manage the rebounding and spread of visceral leishmaniasis.
Objective: To investigate the prevalence of Cryptosporidium infection and the distribution of parasite species and genotypes among HIV-positive individuals in Jiangxi Province.
Methods: HIV-positive individuals' sociodemographic and clinical data were collected from three AIDS designated hospitals in Jiangxi Province from January 2022 to March 2023. Subjects' stool samples were collected, and genomic DNA was extracted from stool samples. Nested PCR assay was performed based on the small subunit ribosomal RNA (SSU rRNA) gene of Cryptosporidium, and Cryptosporidium gp60 gene was amplified in stool samples positive for the SSU rRNA gene. The second-round PCR amplification product was checked with 1.5% agarose gel electrophoresis, and the products of suspected positive amplifications were sequenced, followed by sequence alignment. The phylogenetic tree was created using the Neighbor-Joining method with the software MEGA 11.0, to characterize the species, genotypes and sub-genotypes of Cryptosporidium.
Results: A total of 382 HIV-positive individuals were enrolled, with two cases identified with Cryptosporidium infection (0.52% prevalence), and both cases had no abdominal pain or diarrhea. Following sequencing and sequence alignment, the gene sequences of these two Cryptosporidium isolates shared 99.76% and 99.88% similarity with the gene sequence of C. meleagridis isolates. Phylogenetic analysis based on the Cryptosporidium SSU rRNA gene sequence identified the species of these two Cryptosporidium-positive stool samples as C. meleagridis. Following nested PCR amplification of the Cryptosporidium gp60 gene, sequencing and sequence alignment, the two C. meleagridis isolates were characterized as III eA17G2R1 and III bA25G1R1a sub-genotypes, and the sub-genotype III bA25G1R1a was firstly described in humans.
Conclusions: The prevalence of Cryptosporidium is low among HIV-positive individuals in Jiangxi Province. The likelihood of Cryptosporidium infection cannot be neglected among HIV-positive individuals without diarrhea.
Objective: To evaluate the auxiliary diagnostic value of T cells spot test of Mycobacterium tuberculosis infection (T-SPOT.TB) for pulmonary and extra-pulmonary tuberculosis among the elderly.
Methods: A total of 173 elderly patients at ages of 60 years and older and with suspected tuberculosis that were admitted to People's Hospital of Xinjiang Uygur Autonomous Region during the period from October 2022 through February 2024 were enrolled, and all patients underwent T-SPOT.TB, acid fast staining and GeneXpert MTB/RIF tests. The etiological tests of MTB served as a gold standard, and the diagnostic values of T-SPOT.TB, acid fast staining and GeneXpert MTB/RIF tests for pulmonary and extra-pulmonary tuberculosis were compared among the elderly patients.
Results: Of the 173 elderly patients suspected of tuberculosis, there were 44 patients definitely diagnosed with pulmonary tuberculosis, 30 cases with extra-pulmonary tuberculosis, and 99 cases without tuberculosis. The sensitivities of T-SPOT.TB, acid fast staining and GeneXpert MTB/RIF tests were 86.5%, 27.0% and 54.1% for diagnosis of tuberculosis. The sensitivities of T-SPOT.TB were 86.4% and 86.7% for diagnosis of pulmonary tuberculosis and extra-pulmonary tuberculosis, with an 80.8% specificity for diagnosis of tuberculosis. The sensitivities of GeneXpert MTB/RIF were 56.8% and 50.0% for diagnosis of pulmonary tuberculosis and extra-pulmonary tuberculosis, with a 100.0% specificity each, and the sensitivities of acid fast staining were 31.8% and 20.0% for diagnosis of pulmonary tuberculosis and extra-pulmonary tuberculosis, with a 100.0% specificity each. In addition, the areas under the receiver operating characteristic curve were 0.836, 0.635 and 0.770 for diagnosis of tuberculosis with T-SPOT.TB, acid fast staining and GeneXpert MTB/RIF tests among the elderly patients, respectively.
Conclusions: T-SPOT.TB has a high auxiliary diagnostic value for both pulmonary and extra-pulmonary tuberculosis among elderly patients.
Objective: To investigate the origin of Biomphalaria straminea in China, so as to provide insights into assessment of schistosomiasis mansoni transmission risk and B. straminea control.
Methods: Guanlan River, Dasha River, Shenzhen Reservoir, upper and lower reaches of Kuiyong River, and Xinzhen River in Shenzhen, China, were selected as sampling sites. Ten Biomphalaria samples were collected from each site, and genomic DNA was extracted from Biomphalaria samples. DNA samples were obtained from 15 B. straminea sampled from 5 sampling sites in Minas Gerais State, Pará State, Federal District, Pernambuco State, and Sao Paulo State in Brazil, South America. Cytochrome c oxidase I (COI) and mitochondrial 16S ribosomal RNA (16S rRNA) genes were sampled using the above DNA templates, and the amplified products were sequenced. The COI and 16S rRNA gene sequences were downloaded from GenBank, and the sampling sites were acquired. All COI and 16S rRNA gene sequences were aligned and evolutionary trees of B. straminea were created based on COI and 16S rRNA gene sequences to identify the genetic similarity and evolutionary relationship between B. straminea samples from China and South America.
Results: A total of 60 COI gene sequences with a length of 529 bp and 3 haplotypes were obtained from B. straminea sampled from China. There were 165 COI gene sequences of B. straminea retrieved from GenBank, and following alignment with the above 60 gene sequences, a total of 33 haplotypes were obtained. Phylogenetic analysis showed that the three haplotypes of B. straminea from China were clustered into one clade, among which the haplotype China11 and three B. straminea samples from Brazil retrieved from GenBank belonged to the same haplotype. Geographical evolution analysis showed that the B. straminea samples from three sampling sites along eastern coasts of Brazil had the same haplotype with China11, and B. straminea samples from other two sampling sites were closely, genetically related to China11. A total of 60 16S rDNA gene sequences with approximately 322 bp in length were amplified from B. straminea in China, with 2 haplotypes identified. A total of 70 16S rDNA gene sequences of B. straminea were captured from GenBank. Phylogenetic analysis showed that Biomphalaria snails collected from China were clustered into a clade, and the haplotype China64 and the haplotype 229BS from Brazil shared the same haplotype. The 49 16S rDNA gene sequences of B. straminea from 25 sampling sites in southern Brazil, which were captured from GenBank, were included in the present analysis, and the B. straminea from 3 sampling sites shared the same haplotype with China64 in China. Geographical evolution
CRISPR/Cas system, an adaptive immune system with clustered regularly interspaced short palindromic repeats, may interfere with exogenous nucleic acids and protect prokaryotes from external damages, is an effective gene editing and nucleic acid detection tools. The CRISPR/Cas system has been widely applied in virology and bacteriology; however, there is relatively less knowledge about the application of the CRISPR/Cas system in parasitic diseases. The review summarizes the mechanisms of action of the CRISPR/Cas system and provides a comprehensive overview of their application in gene editing and nucleic acid detection of parasitic diseases, so as to provide insights into future studies on parasitic diseases.
Objective: To investigate the involvement of the high mobility group box protein B1 (HMGB1)-Toll-like receptor 2 (TLR2)/TLR4-nuclear factor κB (NF-κB) pathway in the intestinal mucosal injury induced by Cryptosporidium parvum infection, and to examine the effect of oxymatrine (OMT) on C. parvum infection in mice.
Methods: Forty SPF 4-week-old BALB/c mice were randomly divided into four groups, including the control group, infection group, glycyrrhizin (GA) group and OMT group. Each mouse was orally administered with 1 × 105 C. parvum oocysts one week in the infection, GA and OMT groups following dexamethasone-induced immunosuppression to model C. parvum intestinal infections in mice. Upon successful modeling, mice in the GA group were intraperitoneally injected with GA at a daily dose of 25.9 mL/kg for successive two weeks, and animals in the OMT group were orally administered OMT at a daily dose of 50 mg/kg for successive two weeks, while mice in the control group were given normal food and water. All mice were sacrificed two weeks post-treatment, and proximal jejunal tissues were sampled. The pathological changes of mouse intestinal mucosal specimens were observed using hematoxylin-eosin (HE) staining, and the mouse intestinal villous height, intestinal crypt depth and the ratio of intestinal villous height to intestinal crypt depth were measured. The occludin and zonula occludens protein 1 (ZO1) expression was determined in mouse intestinal epithelial cells using immunohistochemistry, and the relative expression of HMGB1, TLR2, TLR4, myeloid differentiation primary response gene 88 (MyD88) and NF-κB p65 mRNA was quantified in mouse jejunal tissues using quantitative real-time PCR (qPCR) assay.
Results: HE staining showed that the mouse intestinal villi were obviously atrophic, shortened, and detached, and the submucosal layer of the mouse intestine was edematous in the infection group as compared with the control group, while the mouse intestinal villi tended to be structurally intact and neatly arranged in the GA and OMT groups. There were significant differences among the four groups in terms of the mouse intestinal villous height (F = 6.207, P = 0.000 5), intestinal crypt depth (F = 6.903, P = 0.000 3) and the ratio of intestinal villous height to intestinal crypt depth (F = 37.190, P < 0.000 1). The mouse intestinal villous height was lower in the infection group than in the control group [(321.9 ± 41.1) μm vs. (399.5 ± 30.9) μm; t = 4.178, P < 0.01] and the GA group [(321.9 ± 41.1) μm vs. (383.7 ± 42.7) μm; t = 3.130, P < 0.01], and the mouse intestinal crypt depth was greater in the infection group [(185.0 ± 35.9) μm] than in the control group [(128.4 ± 23.6) μm] (t = 3.877, P < 0.01) and GA group [(143.3 ± 24.7) μm]