Wild rodents in three provinces of China exhibit a wide range of Enterocytozoon bieneusi diversity.

Introduction: Enterocytozoon bieneusi is one of the most important zoonotic pathogens, responsible for nearly 90% of human infections. Its host spectrum is broad in China, encompassing humans, non-human primates, domestic animals, wildlife, and wastewater. Wild rodents have the potential to act as carriers of E. bieneusi, facilitating the parasite's transmission to humans and domestic animals. Methods: The present study involved the collection of 344 wild rodents, representing nine species, from three provinces in China. The prevalence and genotypes of E. bieneusi were determined through amplification of the ITS gene. Evolutionary analysis was conducted using Mega 5.0 with the neighbor-joining method (Kimura 2-parameter model, 1,000 replicates). Results: Among the sampled wild rodents, 41 (11.92%) were tested positive for E. bieneusi. Rattus flavipectus exhibited the highest prevalence (11/39), while Bandicota indica and Rattus rattus sladeni showed no infections (0/39 and 0/5, respectively), highlighting significant differences. Environmental factors strongly influenced E. bieneusi infection; rodents residing in lake beaches (10.27%, 15/146) and fields (19.95%, 18/95) were more susceptible compared to those in mountainous areas (7.77%, 8/103). The study identified four known genotypes (D, Type IV, SDD5, PigEBITS7) and five novel genotypes (HNRV-1 to HNRV-3, GXRL-1, GXRL-2) in the investigated wild rodents, with Genotype D exhibiting the highest prevalence. Discussion: Remarkably, this study reports the presence of E. bieneusi, R. flavipectus, M. fortis, A. agrarius, R. losea, and N. lotipes for the first time. These findings underscore the common occurrence of E. bieneusi infection in wild rodents in China, highlighting its diverse nature and significant potential for zoonotic transmission. Hence, it is imperative to conduct a comprehensive epidemiological investigation of rodent infection with E. bieneusi, particularly focusing on wild rodents that are closely associated with humans. Additionally, developing appropriate measures and monitoring strategies to minimize the risk of infection is essential.

Existence of Blastocystis infection in bar-headed goose (Anser indicus).

Blastocystis is a common intestinal protist in humans and animals. Currently, Blastocystis infection in bar-headed geese is unknown. To understand the prevalence and distribution of Blastocystis subtypes in bar-headed geese, fecal samples were collected from 358 bar-headed geese in three regions. The total infection rate of Blastocystis in bar-headed in China was 5.9% (21/358), with 5.0% (6/120) in Aba (Ngawa) Tibetan and Qiang Autonomous Prefect, Sichuan province, 11.8% (14/119) in Maqu county, Gansu province, and 0.8% (1/119) in Caohai, Wei ning county, Guizhou province. The differences in prevalence rates by region were statistically significant. Sequences analyses showed that one known subtype (ST7, n = 16) and one potentially novel ST (n = 5) in bar-headed geese were detected in this study. This is the first report on the prevalence and subtype distribution of Blastocystis in bar-headed geese, which will improve our understanding of the epidemiology and public health implications of Blastocystis infection in wild migratory birds.

Prevalence and subtypes of Blastocystis in wild rodents from three provinces in China.

Introduction: Blastocystis is one of the most critical intestinal protozoans in various hosts, including humans and mice. To determine the status of Blastocystis infection in wild rodents in China. Methods: A total of 344 faecal samples were collected from seven wild rodent species from three provinces, and the small subunit ribosomal RNA (SSU rRNA) genes of Blastocystis were amplified to determine their prevalence and subtypes. Results: Of the 344 samples, 54 (15.70%) were detected as Blastocystis-positive. The prevalence of Blastocystis was 26.14% (40/153), 7.95% (7/88), and 6.80% (7/103) in wild rodents from Hunan Province, Yunnan Province, and Guangxi Province, respectively. The prevalence of Blastocystis in different wild rodent species varied from 0.00% (0/13) in Mus musculus to 40.00% (2/5) in Rattus rattus sladeni. The prevalence of Blastocystis in samples from the lake beach area (27.40%, 40/146) was significantly higher than in those from the mountain (6.80%, 7/103) and field regions (7.37%, 7/95). The prevalence in different seasons was 26.14% in summer (40/153), 7.95% in autumn (7/88), and 6.80% in winter (7/103). Moreover, a total of two Blastocystis subtypes were identified in the investigated wild rodents, including ST4 and ST5. Discussion: The present study discovered the existence of Blastocystis infection in Rattus favipectus, Microtus fortis, Apodemus agrarius, Bandicota indica, Rattus rattus sladeni, and Rattus losea, expanding the host range of this parasite. The findings also demonstrate that wild rodents may be an important potential infection source for Blastocystis infection in humans and other animals.

The prevalence and genotypes of Cryptosporidium spp. in bar-headed goose (Anser indicus) in China.

Cryptosporidium spp. is an important foodborne and waterborne pathogen in humans and animals, causing diarrhoea in humans and respiratory and gastrointestinal diseases in birds. However, reports of Cryptosporidium infection in bar-headed goose are limited. To determine the infection rate and species/genotypes of Cryptosporidium in bar-headed goose in China, a total of 358 fecal samples were collected from 3 regions. Nested PCR was used to amplify Cryptosporidium SSU rRNA regions from the fecal extracted-DNA samples. The total infection rate of Cryptosporidium in bar-headed in China was 3.9 % (14/358), with 4.2 % (5/120) in Aba (Ngawa) Tibetan and Qiang Autonomous Prefect, Sichuan province, 7.6 % (9/119) in Maqu county, Gansu province, and 0.0 % (0/119) in Caohai, Wei ning county, Guizhou province. The differences in prevalence rate by region were statistically significant. All positive samples were identified as Cryptosporidium goose genotype I (n = 14). This is the first systematic investigation of the epidemiological status and dominant species/genotypes of Cryptosporidium in bar-headed goose in China, thereby enhancing our understanding of the epidemiology of Cryptosporidium infection in wild migratory birds.

A Strategy to Optimize the Oligo-Probes for Microarray-based Detection of Viruses / 中国病毒学

DNA microarrays have been acknowledged to represent a promising approach for the detection of viral pathogens. However, the probes designed for current arrays could cover only part of the given viral variants, that could result in false-negative or ambiguous data. If all the variants are to be covered, the requirement for more probes would render much higher spot density and thus higher cost of the arrays. Here we have developed a new strategy for oligonucleotide probe design. Using type I human immunodeficiency virus (HIV-1) tat gene as an example, we designed the array probes and validated the optimized parameters in silico. Results show that the oligo number is significantly reduced comparing with the existing methods, while specificity and hybridization efficiency remain intact. The adoption of this method in reducing the oligo numbers could increase the detection capacity for DNA microarrays, and would significantly lower the manufacturing cost for making array chips.