Epidemiology, Pathophysiology, Diagnosis, and Management of Cerebral Toxoplasmosis.

Toxoplasma gondii is known to infect a considerable number of mammalian and avian species and a substantial proportion of the world's human population. The parasite has an impressive ability to disseminate within the host's body and employs various tactics to overcome the highly regulatory blood-brain barrier and reside in the brain. In healthy individuals, T. gondii infection is largely tolerated without any obvious ill effects. However, primary infection in immunosuppressed patients can result in acute cerebral or systemic disease, and reactivation of latent tissue cysts can lead to a deadly outcome. It is imperative that treatment of life-threatening toxoplasmic encephalitis is timely and effective. Several therapeutic and prophylactic regimens have been used in clinical practice. Current approaches can control infection caused by the invasive and highly proliferative tachyzoites but cannot eliminate the dormant tissue cysts. Adverse events and other limitations are associated with the standard pyrimethamine-based therapy, and effective vaccines are unavailable. In this review, the epidemiology, economic impact, pathophysiology, diagnosis, and management of cerebral toxoplasmosis are discussed, and critical areas for future research are highlighted.

Prevalence, risk factors and genotype distribution of Toxoplasma gondii DNA in soil in China.

In the present study, we performed a cross-sectional survey to determine the occurrence and genotype distribution of T. gondii DNA in soil samples collected from different sources from six geographic regions in China. Between March 2015 and June 2017, 2100 soil samples were collected from schools, parks, farms and coastal beaches, and examined for T. gondii DNA using three PCR assays targeting 529-bp repeat element (RE) sequence, B1 gene and ITS-1 gene sequences. Also, we investigated whether geographic region, soil source and type, and sampling season can influence the prevalence of T. gondii DNA in the soil. Soil samples collected from farms and parks had the highest prevalence, whereas samples collected from school playgrounds and coastal beaches had the lowest prevalence. PCR assays targeting 529-bp RE and ITS-1 gene sequences were more sensitive than the B1 gene-based assay. Positive PCR products were genotyped using multi-locus PCR-RFLP, and ToxoDB #9 was the predominant genotype found in the contaminated soil samples. Multiple logistic regression identified factors correlated significantly with the presence of T. gondii DNA in the soil to be the source of the soil, including farms (odds ratio 3.10; 95% confidence interval [CI], 1.52 to 6.29; p = 0.002) and parks (2.59; 95% CI 1.28 to 5.27; p = 0.009). These results show that Chinese soil hosts T. gondii of the most prevalent genotype in China (ToxoDB#9) and that the soil type influences infection patterns.

Veterinary parasitology teaching in China in the 21st century - Challenges, opportunities and perspectives.

China has made significant achievements in social-economic development in the last three decades, and the numbers of livestock and companion animals are rapidly increasing. Some advances have been made in the control and prevention of animal parasitic diseases, but there are still some significant challenges, particularly in relation to foodborne parasitic zoonoses and vector-borne diseases. In addition, new molecular (e.g., genomic and transcriptomic) technologies have been developed and are gradually being introduced into the veterinary parasitology field. Therefore, teaching of veterinary parasitology in Chinese universities has undergone significant changes over the years, in terms of topics, depth and breadth, and also in the ways in which courses are delivered. In this article, we describe the current status of veterinary parasitology teaching at the undergraduate and postgraduate levels in Chinese universities, summarise changes and improvement in veterinary parasitology teaching, and discuss the challenges and opportunities for veterinary parasitology teaching in the 21st century, including the use of new teaching technologies and the integration of the "One Health" concept into veterinary parasitology courses.

Prevalence and burden of Toxoplasma gondii infection in HIV-infected people: a systematic review and meta-analysis.

BACKGROUND: Worldwide, 30% of the world's population have antibodies to the intracellular protozoan parasite Toxoplasma gondii and about 36·7 million people are infected with HIV, but little is known about the prevalence of co-infection with T gondii and HIV. We aimed to characterise the epidemiology and burden of T gondii co-infection in people with HIV infection. METHODS: In this systematic review and meta-analysis, we searched PubMed, Embase, Google Scholar, ScienceDirect, Chinese Web of Knowledge, Wanfang, and Chongqing VIP databases for studies reporting T gondii infection in HIV-infected people from inception to Feb 29, 2016. Studies were included if they investigated people with HIV infection and presented data that allowed us to establish the prevalence of T gondii infection. We excluded reviews, repeated studies, or animal studies, as well as studies that provided the final results without raw data, had a sample size less than 30 people, had unclear diagnostic methods of T gondii infection, or that included populations with increased risk of T gondii infection. We extracted the numbers of patients with HIV infection and T gondii co-infection from the identified studies. We estimated pooled prevalence of T gondii infection in HIV-infected people by a random-effects model, and evaluated its overall infection burden worldwide. FINDINGS: Our search identified 7843 records and after removal of duplicates and initial screening, we reviewed 312 studies in full. Of these articles, 238 were excluded, leaving 74 studies that included 25 989 HIV-infected people from 34 countries. Of these people, 7326 had T gondii co-infection and we estimated the pooled worldwide prevalence of T gondii infection to be 35·8% (95% CI 30·8-40·7). 2353 of 8837 of people in Asia and the Pacific had co-infection with T gondii and HIV (prevalence 25·1%, 95% CI 19·0-31·2), and prevalence was low in this region compared with that in sub-Saharan Africa (44·9%, 32·3-57·5, 2129/5686; odds ratio [OR] 0·61), Latin America and the Caribbean (49·1%, 27·9-70·4, 510/980; OR 0·33), and North Africa and the Middle East (60·7%, 24·1-97·3, 245/439; OR 0·29). 1561 of 3780 people in low-income countries had co-infection (54·7%, 95% CI 35·8-73·5), which was higher than in middle-income countries (34·2%, 27·4-40·9, 3632/11 540; OR 1·53) and high-income countries (26·3%, 20·4-32·2, 2133/10 669; OR 2·82). Worldwide, we calculated that there were roughly 13 138 600 (95% CI 11 303 600-14 936 900) cases of T gondii co-infection in HIV-infected people, with 87·1% in sub-Saharan Africa (11 449 500 cases, 95% CI 8 236 500-14 662 500). INTERPRETATION: Our findings suggest that people with HIV infection have a very high burden of T gondii infection, especially in sub-Saharan Africa, and emphasise the importance of routine surveillance for T gondii infection in all HIV-infected people. FUNDING: National Natural Science Foundation and the Special Fund for Agro-scientific Research in the Public Interest in China.