A period of about a decade has been estimated to pass for the emergence of a new infectious strain of a virus that may lead to the occurrence of a pandemic one. It is now suggested that the variants of the 1918 H1N1 and coronavirus disease-19 pandemics could have existed in humans after the initial cross-species introduction to humans and underwent multiple low-level seasonal epidemics before the occurrence of their outbreaks. They share similarities in the continuation, widespreadness due to high transmissibility, high fatality rate and clinical symptoms. They are assumed to share a similar principle of a zoonotic source and a cross-species pathway for transmission. They show some similarities in their pathogenesis with other enveloped viruses: Severe Acute Respiratory Syndrome Coronavirus-1 (SARS-CoV-1), Middle East respiratory syndrome coronavirus (MERS-CoV), human immunodeficiency virus, Ebola, Lassa and measles viruses. The highly pathogenic nature of these viruses and their genetic variants may depend on their binding affinity for host cell receptors, whereby they efficiently circumvent or block host cell immune responses triggered by cytokines (interferon). High transmission rates and viral pathogenicity are attributed to glycan moieties that facilitate virus binding to host multiple receptors and cell entry, thereby helping viruses to evade immune recognition and response. Also, mucosa glycotopes are a matter of concern that play as primary sites for virus attachment and body entry. Finding general lectins or ligands that block the viral–host receptors interaction or identifying individual glycotopes is the therapeutic and prognosis topic that demands the main focus.

据估计，大约需要十年的时间才能出现一种新的感染性病毒株，这种病毒株可能会导致大流行性病毒的发生。现在表明，1918 年 H1N1 和冠状病毒病 19 大流行的变种可能在最初跨物种引入人类后就已经存在于人类中，并在爆发之前经历了多次低水平的季节性流行。由于高传播性、高致死率和临床症状，它们在持续性、广泛性方面具有相似性。假定它们具有相似的人畜共患病源原则和跨物种传播途径。它们在发病机制上与其他包膜病毒有一些相似之处：严重急性呼吸系统综合症冠状病毒-1 (SARS-CoV-1)、中东呼吸综合征冠状病毒 (MERS-CoV)、人类免疫缺陷病毒、埃博拉病毒、拉沙病毒和麻疹病毒。这些病毒及其遗传变异体的高致病性可能取决于它们对宿主细胞受体的结合亲和力，从而有效地规避或阻断由细胞因子（干扰素）触发的宿主细胞免疫反应。高传播率和病毒致病性归因于聚糖部分，这些聚糖部分促进病毒结合宿主多个受体和细胞进入，从而帮助病毒逃避免疫识别和反应。此外，粘膜糖表位是一个值得关注的问题，它是病毒附着和进入人体的主要场所。