Lifeng Zhao

To determine the epidemiological status of influenza and understand the distribution of common respiratory viruses in adult patients with influenza-like illness (ILI) cases in Taiyuan City, Shanxi Province, China, epidemiological data between 2018 and 2019 were retrieved from the China Influenza Surveillance Information System, and two sentinel ILI surveillance hospitals were selected for sample collection. All specimens were screened for influenza virus (IFV) and the other 14 common respiratory viruses using real-time polymerase chain reaction. The results of the 2-year ILI surveillance showed that 26,205 (1.37%) of the 1,907,869 outpatients and emergency patients presented with ILI, with an average annual incidence of 297.75 per 100,000 individuals, and ILI cases were predominant in children <15 years (21,348 patients, 81.47%). Of the 2713 specimens collected from adult patients with ILI, the overall detection rate of respiratory viruses was 20.13%, with IFV being the most frequently detected (11.79%) and at a relatively lower rate than other respiratory viruses. Further subtype analysis indicated an alternating or mixed prevalence of H1N1 (2009), H3N2, Victoria, and Yamagata subtypes. This study provides a baseline epidemiological characterization of ILI and highlights the need for a nationwide detection and surveillance system for multiple respiratory pathogens.

Background: Mitochondrial myopathies (MMs) are a group of multi-system diseases caused by abnormalities in mitochondrial DNA (mtDNA) or mutations of nuclear DNA (nDNA). The diagnosis of mitochondrial myopathy (MM) is reliant on the combination of history and physical examination, muscle biopsy, histochemical studies, and next-generation sequencing. Patients with MMs have diverse clinical manifestations. In the contemporary literature, there is a paucity of reports on cardiac structure and function in this rare disease. We report a Chinese man with MM accompanied with both acute right heart failure and left ventricular hypertrophy. Case presentation: A 49-year-old man presented with clinical features suggestive of MM, i.e., ophthalmoparesis, weakness of the pharyngeal and extremity muscles, and respiratory muscles which gradually progressed to respiratory insufficiency. He had a family history of mitochondrial myopathy. He had increased levels of serum creatine kinase and lactate. Muscle biopsy of left lateral thigh revealed 8% ragged red fibers (RRF) and 42% COX-negative fibers. Gene sequencing revealed a novel heterozygote TK2 variant (NM_001172644: c.584T>C, p.Leu195Pro) and another heterozygous variant (NM_004614.4:c.156+958G>A; rs1965661603) in the intron of TK2 gene. Based on these findings, we diagnosed the patient as a case of MM. Echocardiography revealed right heart enlargement, pulmonary hypertension, left ventricular hypertrophy, and thickening of the main pulmonary artery and its branches. The patient received non-invasive ventilation and coenzyme Q10 (CoQ10). The cardiac structure and function were restored at 1-month follow-up. Conclusions: This is the first report of reversible cardiac function impairment and left ventricular hypertrophy in a case of adult-onset MM, nocturnal hypoxia is a potential mechanism for left ventricular hypertrophy in patients with MM.

In recent years, the prevalence of hand, foot, and mouth disease (HFMD) caused by enteroviruses other than enterovirus A71 (EV-A71) and coxsackievirus A16 (CVA16) has gradually increased. The throat swab specimens of 2701 HFMD cases were tested, the VP1 regions of CVA10 RNA were amplified using RT-PCR, and phylogenetic analysis of CVA10 was performed. Children aged 1–5 years accounted for the majority (81.65%) and boys were more than girls. The positivity rates of EV-A71, CVA16, and other EVs were 15.22% (219/1439), 28.77% (414/1439), and 56.01% (806/1439), respectively. CVA10 is one of the important viruses of other EVs. A total of 52 CVA10 strains were used for phylogenetic analysis based on the VP1 region, 31 were from this study, and 21 were downloaded from GenBank. All CVA10 sequences could be assigned to seven genotypes (A, B, C, D, E, F, and G), and genotype C was further divided into C1 and C2 subtypes, only one belonged to subtype C1 and the remaining 30 belonged to C2 in this study. This study emphasized the importance of strengthening the surveillance of HFMD to understand the mechanisms of pathogen variation and evolution, and to provide a scientific basis for HFMD prevention, control, and vaccine development.