In recent years, mpox virus Clade Ib has emerged as a significant global public health threat due to its rapid transmission and potential for severe disease outcomes. This strain was first identified in the Democratic Republic of the Congo (DRC) in September 2023 and began spreading to neighboring African countries by July 2024. It was subsequently imported through international travel to 12 non-African countries across Asia, Europe, and the Americas. Clade Ib exhibits increased transmissibility, and current data suggest that infections may lead to more severe symptoms, with higher risks of severe illness and mortality, particularly among vulnerable populations such as children, pregnant individuals, and immunocompromised groups (e.g., people living with HIV/AIDS). Epidemiologically, Clade Ib primarily spreads through sexual contact, close household contact, and healthcare-related exposure. This review aims to provide an overview of the current understanding of mpox virus Clade Ib, including its genetic characteristics, epidemiological patterns, and prevention and control strategies. Additionally, it discusses the strategies and interventions needed to address this emerging threat.

Measles is an acute and highly contagious viral disease that poses significant public health challenges globally. Since 2001, continuous virologic surveillance has been conducted in Shanghai, enabling a comprehensive analysis of the evolution of the nucleoprotein (N gene) and fusion gene (F gene) of the measles virus (MeV) over a 21-year period. Between 2001 and 2022, there were a total of 1405 MeV strains isolated by the Shanghai Center for Disease Control and prevention (SCDC), including 6 strains of genotype D8, 8 strains of genotype B3, 12 strains of genotype H1b, and the remaining strains of genotype H1a. Reverse transcription polymerase chain reaction (RT-PCR) was used to amplify the 3' end of the N gene (450 nt) and the complete sequence of the F gene (1622 nt) from the viral isolates. Sequencing of the RT-PCR products was followed by nucleotide and amino acid phylogenetic analyses. The substitution rates were for the F and N genes in Shanghai were determined to be 0.89 × 10^-3 and 2.20 × 10^-3 substitutions site^/year, respectively. Globally, the nucleotide and amino acid similarities of the N gene among 13,498 MeV isolates ranged from 89.1 %-100.0 % and 90.2 %-100.0 %, respectively. Notably, the F gene exhibited 16 high-amino-acid-mutation sites, most of which differed among H1a MeV strains compared to the Shanghai-191 vaccine strain. The deletion of the glycosylation site at aa 9-11(NVS) was primarily observed in H1a and H1b of MeV strains. However, critical functional sites in the F gene remained conserved. In conclusion, the previously predominant indigenous H1a wild-type measles virus (MeV) has not been detected for over two years, with only imported MeV genotypes currently being identified. It is crucial to strengthen the surveillance of MeV genotypes to facilitate the timely identification and containment of imported measles cases, thereby preventing potential outbreaks.

Objectives: Understanding the antibody response in monkeypox virus (MPXV)-infected and uninfected individuals is essential for developing next-generation MPXV vaccines. This study aimed to characterize neutralizing antibody (NAb) and antibody-dependent cellular cytotoxicity (ADCC) responses in both groups, providing insights into immune protection and vaccine design. Methods: A recombinant vaccinia Tian Tan (VTT) virus was utilized to develop high-throughput luciferase-reporter-based neutralization and ADCC assays. These assays were applied to evaluate the presence and levels of poxvirus-specific antibodies in MPXV-infected and uninfected individuals, including those vaccinated with vaccinia-based vaccines. Results: Poxvirus-specific NAbs were detected in MPXV-negative individuals with prior vaccinia vaccination. However, MSM individuals exhibited significantly lower pre-existing NAb levels than non-MSM individuals, potentially contributing to their higher susceptibility to MPXV infection. In individuals with mild MPXV infection, robust NAb and ADCC responses were observed, regardless of vaccination status. Additionally, HIV-positive individuals demonstrated comparable antibody responses following MPXV infection. Conclusions: These findings highlight the potential role of pre-existing NAbs in MPXV susceptibility and the strong immune response elicited by mild MPXV infection. Further research is needed to determine whether MPXV-specific antibodies mitigate disease progression, which could inform the development of effective MPXV vaccines.

Human respiratory syncytial virus (HRSV) is a major cause of severe lower respiratory tract infections in infants, young children, and older adults worldwide. With the approval of nirsevimab and HRSV vaccines, accurate measurement of neutralizing antibody levels has become essential for vaccine evaluation, immunization strategy design, and seroepidemiology. The plaque reduction neutralization test (PRNT) remains the gold standard, but it is slow, low-throughput, and requires high biosafety. In recent years, newer methods including focus reduction neutralization testing (FRNT), pseudovirus neutralization testing (PNT), and fluorescent/luminescent reporter virus systems (RVSs) have improved speed and throughput while maintaining high specificity. This review summarizes the principles, performance, applications, and standardization challenges of these assays, offering methodological guidance for HRSV research and prevention in China.