Symptomatic and Asymptomatic Protist Infections in Hospital Inpatients in Southwestern China
Shun-Xian Zhang,
David Carmena,
Cristina Ballesteros,
Chun-Li Yang,
Jia-Xu Chen,
Yan-Hong Chu,
Ying-Fang Yu,
Xiu-Ping Wu,
Li-Guang Tian,
Emmanuel Serrano
Affiliations
Shun-Xian Zhang
Clinical Research Center, LongHua Hospital Shanghai University of Traditional Chinese Medicine, Shanghai 200032, China
David Carmena
Parasitology Reference and Research Laboratory, National Centre for Microbiology, Health Institute Carlos III, Majadahonda, 28220 Madrid, Spain
Cristina Ballesteros
Wildlife Ecology & Health Group (WE&H), Servei d’Ecopatologia de Fauna Salvatge (SEFaS), Departament de Medicina i Cirurgia Animals, Universitat Autònoma de Barcelona (UAB), E-08193 Bellaterra, Spain
Chun-Li Yang
Department of Clinical Research, the 903rd Hospital of People’s Liberation Army of China, Hangzhou 310013, China
Jia-Xu Chen
Chinese Center for Tropical Diseases Research, National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai 200025, China
Yan-Hong Chu
Chinese Center for Tropical Diseases Research, National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai 200025, China
Ying-Fang Yu
Chinese Center for Tropical Diseases Research, National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai 200025, China
Xiu-Ping Wu
Chinese Center for Tropical Diseases Research, National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai 200025, China
Li-Guang Tian
Chinese Center for Tropical Diseases Research, National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai 200025, China
Emmanuel Serrano
Parasitology Reference and Research Laboratory, National Centre for Microbiology, Health Institute Carlos III, Majadahonda, 28220 Madrid, Spain
Cryptosporidium spp., Entamoeba histolytica, Giardia duodenalis, and Blastocystis sp. infections have been frequently reported as etiological agents for gastroenteritis, but also as common gut inhabitants in apparently healthy individuals. Between July 2016 and March 2017, stool samples (n = 507) were collected from randomly selected individuals (male/female ratio: 1.1, age range: 38–63 years) from two sentinel hospitals in Tengchong City Yunnan Province, China. Molecular (PCR and Sanger sequencing) methods were used to detect and genotype the investigated protist species. Carriage/infection rates were: Blastocystis sp. 9.5% (95% CI: 7.1–12.4%), G. duodenalis 2.2% (95% CI: 1.1–3.8%); and E. histolytica 2.0% (95% CI: 0.9–3.6%). Cryptosporidium spp. was not detected at all. Overall, 12.4% (95% CI: 9.7–15.6) of the participants harbored at least one enteric protist species. The most common coinfection was E. histolytica and Blastocystis sp. (1.0%; 95% CI: 0.3–2.2). Sequence analyses revealed that 90.9% (10/11) of the genotyped G. duodenalis isolates corresponded to the sub-assemblage AI. The remaining sequence (9.1%, 1/11) was identified as sub-assemblage BIV. Five different Blastocystis subtypes, including ST3 (43.7%, 21/48), ST1 (27.1%, 13/48), ST7 (18.8%, 9/48), ST4 (8.3%, 4/48), and ST2 (2.1%, 1/48) were identified. Statistical analyses confirmed that (i) the co-occurrence of protist infections was purely random, (ii) no associations were observed among the four protist species found, and (iii) neither their presence, individually or jointly, nor the patient’s age was predictors for developing clinical symptoms associated with these infections. Overall, these protist mono- or coinfections are asymptomatic and do not follow any pattern.
