Prevalence of HCV Antibody and its Associated Factors: A Study from Sentinel Hospitals in China.

Objective: The prevalence and related factors of serum anti-HCV in different regions and hospitals have not been studied extensively in China. We used routine screening data to determine the prevalence of HCV antibody in hospital patients, evaluate the epidemic trend of hepatitis C and formulate screening strategies. Methods: Patient information and HCV antibody testing results were collected from January 2017 to December 2019 in 77 HCV sentinel hospitals in China. Univariate and multivariate logistic regression was used to determine the characteristics and associations. Results: HCV antibody prevalence rates were distinct among patients in different departments, with a range of 0.33%-6.93%. Patients who were admitted to the liver disease-related departments (a OR = 10.76; 95% CI, 10.27-11.28), Internal Medicine (a OR = 2.87; 95% CI, 2.75-3.00), and Department of Surgery (a OR = 1.95; 95% CI, 1.87-2.04), were more likely to be tested for HCV antibody positive. HCV antibody prevalence was associated with patients aged 45 years and older (a OR = 2.74; 95% CI, 2.69-2.80), testing in infetious disease hospitals (a OR = 2.33; 95% CI, 2.26-2.40) and secondary hospitals (a OR = 1.72; 95% CI, 1.69-1.75). Patients in sentinel hospitals of the Northeast (a OR = 12.75; 95% CI, 12.40-13.11), the Central (a OR = 1.65; 95% CI, 1.61-1.70), and the West (a OR = 1.78; 95% CI, 1.73-1.83) China had higher HCV prevalence than those who were in the Eastern coastal area. Conclusion: Those who were over 45 years old and saw doctors for liver diseases, and invasive diagnosis and treatment should be referred to HCV antibody testing.

[Biological characteristics of HIV-1 isolates circulating in China are linked to its env V3 loop sequence variability].

OBJECTIVE: To investigate the biological characteristics of the HIV-1 isolates circulating in China and to define the association of these properties with env V3 loop sequence variability. METHODS: Primary viruses were isolated from fresh peripheral blood mononuclear cells (PBMCs) using the traditional co-culture method and their capacity of inducing syncytium was tested in MT-2 cells; meanwhile, their coreceptor usage was determined with GHOST-cell lines which stably express CD4 and the chemokine receptor CCR5 or CXCR4. Furthermore, HIV-1 V3 and its flanking region sequences were amplified by nest-polymerase chain reaction (nest-PCR) and sequenced. A GCG software was used to translate the DNA sequences into polypeptide sequences. RESULTS: Five primary viral strains were isolated from 3 different regions in China. The isolates LTG0213 and LTG0214 induced syncytia in MT-2 cells and used CXCR4 as coreceptor. The isolates XJN0021, XJN0091, and SHXDC0041 did not induce syncytia and used CCR5 as coreceptor. There were obvious differences between X4/SI and R5/NSI viruses in env V3 loop sequences. A consensus motif at the positions 8, 11, 18, and 25 in V3 loop was identified as follows: a sequence as "8-TXXS/GXXXXXXR/QXXXXXXE/D-25" will predict the usage of CCR5 coreceptor; a sequence replacing these positions with basic amino acids (except position 25) will very likely predict the usage of CXCR4 coreceptor. CONCLUSION: The biological characteristics of HIV isolates are linked to env V3 loop sequence variability: introducing basic amino acids (or translating from acidic amino acids into neutral amino acids) at the positions 8, 11, 18, and 25 in V3 loop will change viral strain's biological phenotype from NSI/CCR5 to SI/CXCR4. The biological phenotype of HIV-1 can be predicted with V3 loop sequence analysis.