Bao‐Gui Jiang

BACKGROUND: Severe community-acquired pneumonia (SCAP) is associated with a substantial number of hospitalisations and deaths worldwide. Infection or co-infection patterns, along with their age dependence and clinical effects are poorly understood. We aimed to explore the causal and epidemiological characteristics by age, to better describe patterns of community-acquired pneumonia (CAP) and their association with severe disease. METHODS: National surveillance of CAP was conducted through a network of hospitals in 30 provinces in China from 2009-20 inclusive. Patients with CAP were included if they had evidence of acute respiratory tract, had evidence of pneumonia by chest radiography, diagnosis of pneumonia within 24 h of hospital admission, and resided in the study catchment area. For the enrolled patients with CAP, nasopharyngeal and oral swabs were taken and tested for eight viral pathogens; and blood, urine, or expectorated sputum was tested for six bacterial pathogens. Clinical outcomes, including SCAP, were investigated with respect to age and patterns of infections or co-infections by performing binary logistic regression and multivariate analysis. FINDINGS: Between January, 2009, and December, 2020, 18 807 patients with CAP (3771 [20·05%] with SCAP) were enrolled. For both children (aged ≤5 years) and older adults (aged >60 years), a higher overall rate of viral and bacterial infections, as well as viral-bacterial co-infections were seen in patients with SCAP than in patients with non-SCAP. For adults (aged 18-60 years), however, only a higher rate of bacterial-bacterial co-infection was observed. The most frequent pathogens associated with SCAP were respiratory syncytial virus (RSV; 21·30%) and Streptococcus pneumoniae (12·61%) among children, and influenza virus (10·94%) and Pseudomonas aeruginosa (15·37%) among older adults. Positive rates of detection of most of the tested pathogens decreased during 2020 compared with the 2009-19 period, except for RSV, P aeruginosa, and Klebsiella pneumoniae. Multivariate analyses showed SCAP was significantly associated with infection with human adenovirus, human rhinovirus, K pneumoniae, or co-infection of RSV and Haemophilus influenzae or RSV and Staphylococcus aureus in children and adolescents (aged <18 years), and significantly associated with infection with P aeruginosa, K pneumoniae, or S pneumoniae, or co-infection with P aeruginosa and K pneumoniae in adults (aged ≥18 years). INTERPRETATION: Both prevalence and infection pattern of respiratory pathogens differed between patients with SCAP and patients with non-SCAP in an age-dependent manner. These findings suggest potential advantages to age-related strategies for vaccine schedules, as well as clinical diagnosis, treatment, and therapy. FUNDING: China Mega-Project on Infectious Disease Prevention and The National Natural Science Funds of China. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.

BACKGROUND: A tick-borne segmented RNA virus called Jingmen tick virus (JMTV) was recently identified, variants of which were detected in a non-human primate host and fatal patients with Crimean-Congo haemorrhagic fever. We investigated its infectivity and pathogenicity for humans. METHODS: We obtained skin-biopsy, blood and serum samples from patients with tick bites, and used high-throughput sequencing, in situ hybridisation, and serologic testing to diagnose and ascertain the cases of JMTV infection. FINDINGS: A JMTV strain was isolated from the tick Amblyomma javanense into an embryo-derived tick cell line. We obtained sustained passage of JMTV, and revealed that it was able to accumulate in salivary glands of experimentally infected ticks. Four JMTV-infected patients were identified by high-throughput sequencing of skin biopsies and blood samples. The virus replication in skin tissue was visualised by in situ hybridisation. The four patients all had an itchy or painful eschar at the site of tick bite, with or without lymphadenopathy. Immunohistochemical examination revealed remarkable local inflammation manifested as infiltration by neutrophils. Eight patients were identified by serological testing and showed more severe clinical manifestations. Two Ixodes persulcatus ticks detached from patients were positive for JMTV. All JMTV strains identified in this study formed a well-supported sub-lineage, distinct from those previously reported in China. Interpretation The public significance of JMTV should be highly concerning due to its potential pathogenicity for humans and efficient transmission by potential ticks. FUND: China Natural Science Foundation, State Key Research Development Programme, and United Kingdom Biotechnology and Biological Sciences Research Council.

Nationwide nonpharmaceutical interventions (NPIs) have been effective at mitigating the spread of the novel coronavirus disease (COVID-19), but their broad impact on other diseases remains under-investigated. Here we report an ecological analysis comparing the incidence of 31 major notifiable infectious diseases in China in 2020 to the average level during 2014-2019, controlling for temporal phases defined by NPI intensity levels. Respiratory diseases and gastrointestinal or enteroviral diseases declined more than sexually transmitted or bloodborne diseases and vector-borne or zoonotic diseases. Early pandemic phases with more stringent NPIs were associated with greater reductions in disease incidence. Non-respiratory diseases, such as hand, foot and mouth disease, rebounded substantially towards the end of the year 2020 as the NPIs were relaxed. Statistical modeling analyses confirm that strong NPIs were associated with a broad mitigation effect on communicable diseases, but resurgence of non-respiratory diseases should be expected when the NPIs, especially restrictions of human movement and gathering, become less stringent.