2025年 · 第14卷第04期

When you end up in a small town in the Danube valley in Southwest Germany you hardly imagine that an inter-nationally well-known scientist grew up here: Theodor Maximilian Bilharz was born on March 23, 1825, in the town of Sigmaringen. By chance, 130 years later, I happened to be born in the same town. There, I went to school, which later took the name of "Bilharzschule", there was a pharmacy called "Bilharzapotheke", and I walked through "Bilharzstraße". Like most citizens of Sigmaringen, I knew his name but had no idea what he stood for. How could I imagine that this man became famous for having discovered the cause of an important world-wide tropical disease known since antiquity, which is not even endemic in Germany? Why a son of a small town in the green Danube valley should have left his homeland for Egypt?

The sterile insect technique (SIT) requires distinguishing sterile from wild male mosquitoes to evaluate male qualities and maintain an appropriate release ratio for efficient population suppression. Current dye/powder marking methods have limitations and may affect SIT effectiveness, necessitating alternative discrimination strategies. Aedes albopictus naturally harbors two Wolbachia infections (wAlbA/wAlbB), which can be eliminated via tetracycline. Although Wolbachia removal minimally affect host fitness, its impact on microbiota remains unclear. Characterizing post-elimination microbial communities is the first step to identify novel endogenous biomarkers for SIT monitoring.

We analyzed the bacterial diversity and composition of two strains of wild-type GUA (Wolbachia-infected) and GT (Wolbachia-free) mosquitoes using the 16S rRNA V3-V4 region sequencing. qPCR was employed to confirm the relative abundance of four major bacterial genera, while PCR was used to validate selected biomarkers for distinguishing factory-reared sterile males from wild males. Kruskal-Wallis or Mann-Whitney test was used to analyze the comparable parameters between GUA and GT strains.

Five-day-old GUA and GT females showed similar microbial diversity/composition, while young males shared diversity but differed in composition. The core microbiota in both strains consisted of Proteobacteria (64.27%), Firmicutes (16.09%), Actinobacteriota (11.22%), and Bacteroidota (4.96%). Asaia was dominant in both strains (GUA: 47.33%; GT: 32.69%), whereas Enterococcus increased in GT males with aging. Wolbachia was absent in GT mosquitoes, and Elizabethkingia was undetected in GUA males. qPCR further confirmed these trends. PCR analysis revealed that wAlbB exhibited higher stability in differentiating factory-reared GT males from their wild counterparts (96.7% infection in field males, n = 60) compared to wAlbA (61.7%, n = 60) or Enterococcus (65.8%, n = 120). The mark-release-recapture experiment further confirmed the detectability using wAlbB biomarker.

Without obvious fitness costs observed previously in the Ae. albopictus GT strain compared to GUA strain, the removal of Wolbachia significantly changes the microbial composition in male mosquitoes in this study. Wolbachia wAlbB is recommended as a reliable biomarker for distinguishing sterile males from wild males when using GT strain in SIT programs targeting Ae. albopictus.

Toxoplasma gondii is a globally widespread zoonotic parasite, infecting nearly one-third of the human population, often leading to chronic, latent infections. Among the emerging layers of gene regulation, 5-methylcytosine (m⁵C) has emerged as a pivotal post-transcriptional modification in eukaryotes. Despite its growing recognition in various species, the epitranscriptomic landscape of m⁵C in the tachyzoite stage of T. gondii remains largely unexplored. To address this gap, we performed the first comprehensive m⁵C methylation profiling across three major T. gondii genotypes—RH (type I), ME49 (type II), and VEG (type III).

The comparative m⁵C methylation analysis was carried out using methylated RNA immunoprecipitation sequencing (MeRIP-Seq) combined with RNA sequencing (RNA-Seq). Differentially m⁵C-methylated genes (DMMGs) were functionally annotated via Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. By combining methylation and transcriptomic data, we uncovered strain-specific correlations between m⁵C modifications and gene expression. Additionally, expression and methylation patterns of potential regulators identified via BLASTP searches were examined. Statistical analyses were determined by one-way ANOVA.

Our analysis revealed a total of 5129, 4968, and 4577 m⁵C-methylated genes in RH, ME49, and VEG tachyzoites, respectively, with methylation predominantly enriched in the coding sequences. Comparative analysis across different strains uncovered 1710, 1131, and 784 DMMGs in RH versus ME49, RH versus VEG, and ME49 versus VEG, respectively. Functional enrichment analysis highlighted key biological processes, including catalytic activity, transport, phospholipid metabolism and transcription regulation. Furthermore, KEGG pathway analysis identified critical m⁵C-regulated processes such as nucleocytoplasmic transport, DNA replication, and ATP-dependent chromatin remodeling. Virulence-associated secretory effectors exhibited hypermethylation in more virulent strains, such as GRA39 and ROP35. Additionally, several putative m⁵C regulators displayed genotype-specific or conserved expression and methylation patterns.

This study presents the first m⁵C epitranscriptomic atlas of T. gondii tachyzoites, revealing both conserved and genotype-specific mRNA modification networks. These insights significantly increased the understanding of the regulatory role of m⁵C in T. gondii pathogenesis and open promising avenues for the development of vaccines and therapeutics aimed at combating zoonotic toxoplasmosis.

Lowndes County is a predominantly Black rural county in Alabama, in the United States, which has a historical and current legacy of racial discrimination, creating inequitable infrastructure access and adverse health impacts. Over 80% rely on on-site sanitation infrastructure and most are failing. A community assessment of exposure to untreated sewage was conducted using samples from residential drinking water, surface swabs, and soil combined with environmental water and soil samples using culture-based and quantitative polymerase chain reaction (qPCR) methods. Testing varied slightly across samples, due to difficulty of access or availability. Of 43 households, 68% and 55% of houses had detectable presence of human fecal matter indicator in their soils and on their doorsteps, respectively, and 0% had detectable amounts of culturable Escherichia coli in their drinking water. Of 40 houses sampled, 88% tested positive for E. coli in soil samples. Of 39 residences, 31% had positive presence of environmental and zoonotic parasites in soil, but none for Necator americanus, Cryptosporidium species, or Giardia intestinalis. Of the 18 sampled environmental surface waters, 100% tested positive for culturable E. coli, 50% had detectable human fecal matter indicator present, and 27% tested positive for anthropogenic parasites. This work sheds light that there is presence of culturable E. coli, human fecal matter, and anthropogenic parasites in residential soil samples of all sanitation types (municipal, septic tank, and straight piping) and in environmental surface waters throughout the sampled areas. Our findings support the narrative that sanitation infrastructure of all types in Lowndes County, Alabama are compromised and highlights residential and environmental exposure to raw wastewater.

Alveolar echinococcosis (AE), caused by the larval stage of Echinococcus multilocularis, poses a substantial global health challenge due to its high mortality profile. This study reports the inaugural human infection of echinococcosis caused by the Mongolian genotype of E. multilocularis in China, also the first reported indigenous AE case in Inner Mongolia.

A 58-year-old female pastoralist from Inner Mongolia, who had no endemic region exposure history but prolonged occupational contact with dogs, presented with severe AE. Clinical examinations revealed a massive hepatic lesion exceeding 10 cm in diameter, accompanied by elevated eosinophils (0.90 × 10⁹/L) and basophils (0.08 × 10⁹/L). Despite undergoing liver transplantation, the patient succumbed postoperatively. Histopathological confirmation and molecular phylogenetics identified the Mongolian genotype of E. multilocularis infection, distinct from the predominant Asian genotype in China. Potential evidence of zoonotic transmission was discovered through genotype-matched E. multilocularis detection in corsac fox (Vulpes corsac) feces from the grasslands along the shores of Hulun Lake (Hulun Buir City, northeastern Inner Mongolia, China).

This report provides the primary evidence of a locally acquired human AE infection in China caused by the Mongolian genotype of Echinococcus multilocularis. The discovery of this case challenges historical classifications of echinococcosis endemic areas. The findings call for revised AE-endemic identification criteria, improved AE diagnostic protocols, and enhanced AE surveillance in the Inner Mongolia region to generate further epidemiological evidence and information on disease progression.

Emerging and re-emerging infectious diseases in different soci-ecological settings create unprecedented challenges for global public health and socio-economic development. The One Health concept is based on a systemic, transdisciplinary approach and hence captures the interactions between humans and animals, in a given socioecological setting. It could comprehensively address the human-animal-environment interface, the core of zoonotic diseases. Consequently, One Health approach is effective in controlling and eliminating the promoting factors of emerging infectious diseases (EIDs). We explored key principles for the prevention, control and elimination of EIDs through reviewing the transition of public health and global health strategies towards One Health and summarizing some successful experiences in effectively controlling EIDs. Recognizing heterogeneities and strengthening "surveillance-response systems" are the two key principles. It is recommended to promote health equity and conduct cost-effectiveness analysis to address the challenges of heterogeneity. Cross-sectoral collaboration and transdisciplinarity should be strengthened to facilitate the utilizing of systems thinking.

Asian hepatointestinal schistosomiasis due to Schistosoma japonicum is prevalent in the Philippines and in Indonesia, while it is close to elimination in China. The second Asian schistosome, S. mekongi, is found in Cambodia and Laos. The main pathology caused by both species is liver fibrosis, which can cause significant morbidity and mortality, mainly due to portal hypertension leading to bleeding from esophageal varices. Ultrasonography was introduced several decades ago as a safe, fast, non-invasive, and relatively inexpensive technique for assessing chronic schistosomiasis-related hepatic pathology in the clinical and field settings. A standardized ultrasound protocol had been established by experts at a WHO-chaired meeting in Cairo, Egypt, in 1990. The peculiarities of sonomorphologic abnormalities caused by S. japonicum and S. mekongi were not sufficiently covered in the Cairo protocol and not addressed at all in the subsequent WHO chaired meeting in Niamey 1996. At a follow-up WHO-chaired meeting in Phnom Pehnh, Cambodia, in 2002, an attempt was made to develop a protocol for Asian schistosomiasis, but a protocol resulting from this meeting has never been published. Although several studies investigated the use of ultrasonography to assess S. japonicum- and S. mekongi-related sonomorphological morbidity across endemic areas the lack of a standardized protocol hampered the characterization of sonomorphologic abnormalities with regard to progression, reversibility, prognosis, and correlation to morbidity. In addition, the comparison of data from different endemic areas and populations remained difficult. Therefore, a WHO-chiared expert meeting took place in Basel, Switzerland in September 2024 with the aim to establish a standardized ultrasound protocol for reporting the pathology caused by S. japonicum and S. mekongi. The proposed protocol is described in this article.