Childhood suffering: hyper endemic echinococcosis in Qinghai-Tibetan primary school students, China.

BACKGROUND: As part of an ongoing program that aims to use early detection and timely treatment to improve the control of echinococcosis, especially in younger age groups, we undertook a series of active surveys among Qinghai-Tibetan children in the Qinghai Province of Northwestern China in 2011 and 2012. The significant outcomes that resulted from this study emphasize the need to draw attention to echinococcosis, both alveolar echinococcosis (AE) and cystic echinococcosis (CE), so that policy development is promoted and suitable avenues for control are identified in the highly endemic areas on the Tibetan Plateau. METHODS: A total of 19 629 primary school students, aged 6-18 years, with a dominant Tibetan background underwent abdominal ultrasound examination, and 86.4% of the compliant students donated 2-5 ml of venous blood for serological tests. All the abnormal ultrasound results were recorded. If identified as echinococcosis, the disease lesion was assessed according to the WHO-Informal Working Group on Echinococcosis (WHO-IWGE) classification for AE and CE. Among the surveyed students, the prevalence by school was compared among geo-locations, sex and age groups. The clinical image presentations were analyzed according to lesion number, size, the location in the liver and the classification stage. Statistical significance was set at P-value < 0.05 for comparisons among groups. RESULTS: A total of 341 students (1.7%) were identified by ultrasound as having either CE (119, 0.6%) or AE (222, 1.1%). The highest prevalence rates of childhood AE cases occurred in the Tehetu (12.1%) and Moba (11.8%) townships in Dari County. There was a high seropositive rate (37.0%) and a heterogeneous distribution of cases, with a prevalence ranged from 0 to 12.1% for AE and 0-2.9% for CE. Moreover, the seropositive rate ranged from 0.7-45.1% across different schools. CONCLUSIONS: The high prevalence of echinococcosis in Qinghai-Tibetan primary school students reflects a lack of knowledge about Echinococcus spp. transmission. The combination of systematic education for children and regularly performed anthelmintic treatment for dogs could achieve the goal of sustainable hydatidosis control.

Lasiopodomys fuscus as an important intermediate host for Echinococcus multilocularis: isolation and phylogenetic identification of the parasite.

BACKGROUND: Echinococcus multilocularis causes alveolar echinococcosis (AE) and is widely prevalent in Qinghai Province, China, where a number of different species have been identified as hosts. However, limited information is available on the Qinghai vole (Lasiopodomys fuscus), which is hyper endemic to Qinghai Province and may represent a potential intermediate host of E. multilocularis. Thus, L. fuscus could contribute to the endemicity of AE in the area. METHODS: Fifty Qinghai voles were captured from Jigzhi County in Qinghai Province for the clinical identification of E. multilocularis infection via anatomical examination. Hydatid fluid was collected from vesicles of the livers in suspected voles and subjected to a microscopic examination and PCR assay based on the barcoding gene of cox 1. PCR-amplified segments were sequenced for a phylogenetic analysis. E. multilocularis-infected Qinghai voles were morphologically identified and subjected to a phylogenetic analysis to confirm their identities. RESULTS: Seventeen of the 50 Qinghai voles had E. multilocularis-infection-like vesicles in their livers. Eleven out of the 17 Qinghai voles presented E. multilocularis infection, which was detected by PCR and sequencing. The phylogenetic analysis showed that all 11 positive samples belonged to the E. multilocularis Asian genotype. A morphological identification and phylogenetic analysis of the E. multilocularis-infected Qinghai voles confirmed that all captured animals were L. fuscus. CONCLUSIONS: L. fuscus can be infected with E. multilocularis and plays a potential role in the life cycle and epidemiology of E. multilocularis in the Qinghai-Tibetan Plateau of China.