Biosafety and Health最新文献

Enteroviruses (EVs) are classified into 15 species according to their sequence diversity. They include four human EV (A, B, C, and D) and three rhinoviruses (A, B, and C), and cause diseases in millions of people worldwide. Generally, individuals with enteroviral infections have mild clinical symptoms, including respiratory illness, vomiting, diarrhea, dizziness, and fever. More importantly, some members of the human EV family are neurotropic pathogens that may cause a wide range of clinical diseases, such as aseptic meningitis and encephalitis. Previously, the EV that caused the most severe neurotropic symptoms was poliovirus (PV), a member of the EV C group. Poliovirus has been eliminated in most countries through a global vaccination campaign. Non-PV EVs infect the central nervous system (CNS) and are the major EVs causing neurological diseases. These human non-PV EVs include EV A (e.g., EV-A71, CVA6, and CVA16), B (e.g., CVA9 and CVB3, CVB5, echovirus 11 [E11], E30, and E7), C (e.g., CVA24), and D (e.g., EV-D68). Here, we review the relationship between EV infection and CNS diseases and advance in the use of cellular receptors and host immune responses during viral infection.

The objective of this study was to investigate the outbreak of echovirus 11 (ECHO 11) infection in newborns at a hospital in Guangdong Province, China, and to study the effectiveness of prevention and control measures to infer the epidemiological characteristics of ECHO 11 and explore the effective measures for its prevention and control. We performed retrospective analyses of hospital records and laboratory test data. In this outbreak, ten cases of ECHO 11 infection were identified, of which nine cases were nosocomial infections. Most of the cases (90%) were severe, and three died. The onset time interval of 10 patients was 1–4 days, most of which occur in 1–2 days. There were eight (80%) males and two females (20%). The gestational age of the patients was 31 to 40 weeks (mean, 35⁺⁴ weeks; median, 35⁺⁴ weeks). The onset time was 3–26 days (average 9 days; median 8 days). The birth weights of the patients ranged from 1,650 g to 3,450 g (mean 2,385 g; median 2,250 g). We concluded that neonatal infection with ECHO 11 will lead to serious symptoms and high mortality, and is prone to outbreaks of nosocomial infection. We speculate that ECHO 11 is most likely to spread via contact transmission; however, we do not rule out the possibility of droplet transmission. Prevention and control measures can effectively prevent and control hospital enteroviral infections.

Monkeypox (mpox) is a zoonotic disease caused by the mpox virus (MPXV) that has been primarily limited to Central and West African nations since its discovery. The recent spread of the West African lineage of MPXV in historically unaffected countries has raised concerns for global public health. Despite a significant decrease in global mpox cases, there is still a risk of a global resurgence. This study reports the first local case of mpox caused by an imported case in the Chinese mainland. Polymerase chain reaction (PCR) diagnosed the two cases, and the viral genomes were obtained by next-generation sequencing. Genomic analysis revealed that the two strains shared an identical genome sequence and belonged to the B.1.3 branch of the West African lineage, which is the first local case of mpox caused by an imported case in the Chinese mainland, highlighting the potential threat of mpox in China and the immediate need for adequate surveillance measures.

This study aimed to compare the sensitivity of two-phase separation and the filtration method using a mixed cellulose ester (MCE) membrane to detect enteroviruses in sewage samples. From December 2015 to July 2016, four domestic sewage samples (1 L/sample) were collected monthly from the Guangzhou Liede Sewage Treatment Plant, and each sewage sample was divided into two aliquots (500 mL). The sewage sample was concentrated using the two-phase separation and the filtration method using an MCE membrane, and the treated solutions were inoculated into cells for enterovirus isolation. Polymerase chain reaction amplification, VP1 sequencing, and enterovirus molecular typing were performed on the positive isolates. The detection rates of poliovirus (PV) and non-polio enterovirus (NPEV) obtained using the filtration method using an MCE membrane were higher than those using the two-phase separation method. McNemar's test showed that the detection rates of PV, NPEV, type 1 Sabin-like (SL1), type 2 Sabin-like (SL2), and type 3 Sabin-like (SL3) strain were not statistically significant (P > 0.05). In Guangdong Province, China, the detection rates for PV and NPEV were 53.13% and 62.50% (20/32), respectively. Twenty-seven PVs were isolated, three highly variable strains of the type 1 vaccine, with seven nucleotide substitutions in the VP1 region, compared with the type 1 Sabin strains. Eighty-seven strains of NPEV were isolated and nine serotypes were identified, among which coxsackievirus B3 (CVB3), echovirus 6(E6), and echovirus 11(E11) were the dominant strains. The filtration method using an MCE membrane is more sensitive than two-phase separation and can be used as a robust, sensitive, and cost-effective method to isolate enteroviruses from sewage.

In 2008, China launched a national surveillance system for hand-foot-and-mouth disease (HFMD). Several million cases of HFMD are reported every year, coxsackievirus A16 (CVA16) was the leading cause of HFMD epidemic in Yantai city, China in recent years, but the information of epidemiology and molecular characterization of CVA16 in Yantai is limited. The aim of this study is to investigate the epidemiological characteristics and pathogenic spectrum of HFMD, and most importantly, the molecular characterization of CVA16 in Yantai from 2018 to 2021. A total of 2,000 clinical samples were collected in Yantai city from 2018 to 2021 and the enterovirus typing was performed using real-time reverse transcriptase–polymerase chain reaction (qRT-PCR). VP1 coding regions of 41 CVA16 isolates were amplified and Sanger sequenced, and phylogenetic analysis was performed. During the study period, HFMD became prevalent from May to August each year. It peaked in June and declined in September. The incidence was highest in children aged 1 to 5 years, while more common in males than females. 1,617 out of 2,000 clinical collection of samples were tested positive for enterovirus. Among them, 614 were identified as CVA16, 45 were enterovirus A71 (EV A17), and 958 were other enterovirus serotypes. All 41 CVA16 strains belonged to the Bla and B1b genotypes. Homology analysis showed that 41 CVA16 isolates shared 83.2%–100% nucleotide and 93.7%–100% amino acid similarity among themselves. The results of this study update molecular epidemiology of CVA16 and provide a reference for HFMD prevention and control.

Aedes aegypti (Ae. aegypti) is a major vector of dengue virus (DENV) and Zika virus (ZIKV). Understanding the complex interaction mechanisms between mosquito vectors and arboviruses is essential to interrupt virus transmission. This study constructed CYP4C21 knockout (KO) Aag2 cells (Ae. aegypti cells) and confirmed that CYP4C21 KO reduced DENV2 and ZIKV copies in Aag2 cells, which suggests that CYP4C21 may play an important role in mosquito infection with arboviruses. Furthermore, it is the first report of the CYP4 family related to viral infection, which lays the foundation for exploring the role of the CYP4C21 in the interaction of Ae. aegypti and arbovirus and provides novel insights into the function of cytochrome family proteins.

Metagenomic next-generation sequencing (mNGS) has been widely applied to identify pathogens associated with infectious diseases. However, limited studies have explored the use of mNGS-based dynamic pathogen monitoring in intensive care unit patients with severe pneumonia. Here, we present a clinical case of an 86-year-old male patient with severe pneumonia caused by a fungal infection. During the clinical treatment, four mNGS analyses were performed within two consecutive weeks. Various respiratory fungal pathogens, including Candida orthopsilosis, Candida albicans, and Aspergillus fumigatus were detected by mNGS of bronchoalveolar lavage fluid (BALF). Based on conventional pathogen identification and clinical symptoms, the patient was diagnosed with severe pneumonia caused by a fungal infection. The abundance of fungal species decreased gradually in response to antifungal and empirical therapies, and the fungal infections were effectively controlled. In summary, our results demonstrated that mNGS could effectively identify pathogens in patients with severe pneumonia. Additionally, dynamic pathogen monitoring based on mNGS could assist in the precise diagnosis of complex infections and may facilitate rapid induction of the most appropriate therapy.