ABSTRACT
Echovirus 11 (E11) has gained attention owing to its association with severe neonatal infections. From 2018 to 2023, a surge in severe neonatal cases and fatalities linked to a novel variant of genotype D5 was documented in China, France, and Italy. However, the prevention and control of E11 variants have been hampered by limited background data on the virus circulation and genetic variance. Therefore, the present study investigated the circulating dynamics of E11 and the genetic variation and molecular evolution of genotype D5 through the collection of strains from the national acute flaccid paralysis (AFP) and hand, foot, and mouth disease (HFMD) surveillance system in China during 2000-2022 and genetic sequences published in the GenBank database. The results of this study revealed a prevalent dynamic of E11 circulation, with D5 being the predominant genotype worldwide. Further phylogenetic analysis of genotype D5 indicated that it could be subdivided into three important geographic clusters (D5-CHN1: 2014-2019, D5-CHN2: 2016-2022, and D5-EUR: 2022-2023). Additionally, variant-specific (144) amino acid mutation sites and positive-selection pressure sites (132, 262) were identified in the VP1 region. Cluster-specific recombination patterns were also identified, with CVB5, E6, and CVB4 as the major recombinant viruses. These findings provide a preliminary landscape of E11 circulation worldwide and basic scientific data for further study of the pathogenicity of E11 variants.
Subject(s)
Enterovirus B, Human , Evolution, Molecular , Genetic Variation , Genotype , Phylogeny , China/epidemiology , Humans , Enterovirus B, Human/genetics , Enterovirus B, Human/classification , Enterovirus B, Human/isolation & purification , Infant, Newborn , Echovirus Infections/virology , Echovirus Infections/epidemiology , Hand, Foot and Mouth Disease/virology , Hand, Foot and Mouth Disease/epidemiology , InfantABSTRACT
While the novel coronavirus continues to spread worldwide, the reported incubation period has varied between studies and is imprecise due to limited data. A literature search with certain selection criteria was conducted on May 30, 2020. In total, sixty-four articles were included, and 854 individual-level data were extracted from 30 studies for pooled analysis. Of these studies, 72% of them reported a median or mean incubation period of 4-7 days, while our estimated median was 4.9 days (95% confidence interval [CI]: 4.6-5.2). However, the inclusion of 81 asymptomatic and presymptomatic patients, as well as 31 cases with incubation periods exceeding 14 days, led to our estimation of 97.5 th percentile with 19.3 days (95% CI: 17.4-21.4), beyond the currently suggested 14-day quarantine period. Therefore, we appeal to prolong the quarantine duration, especially for areas that have insufficient testing resources, to protect susceptible populations from being infected. Article Summary LineThis article reviewed the COVID-19 studies involving incubation period and provided pooled estimation based on available data from these studies.The result showed that our estimated median incubation period is consistent with the estimates of formal studies but the 97.5 percentile is larger than ever on account of including a number of asymptomatic and presymptomatic patients.These finds suggested that we should properly prolong the isolation or quarantine period in order to identify more patients with longer incubation period and those without any symptoms.
