The human population is in the midst of battling a rapidly-spreading virus— Severe Acute Respiratory Syndrome Coronavirus 2, responsible for Coronavirus disease 2019 or COVID-19. Despite the resurgences in positive cases after reopening businesses in May, the country is seeing a shift in mindset surrounding the pandemic as people have been eagerly trickling out from federally-mandated quarantine into restaurants, bars, and gyms across America. History can teach us about the past, and today’s pandemic is no exception. Without a vaccine available, three lessons from the 1918 Spanish flu pandemic may arm us in our fight against COVID-19. First, those who survived the first wave developed immunity to the second wave, highlighting the potential of passive immunity-based treatments like convalescent plasma and cell-based therapy. Second, the long-term consequences of COVID-19 are unknown. Slow-progressive cases of the Spanish flu have been linked to bacterial pneumonia and neurological disorders later in life, emphasizing the need to reduce COVID-19 transmission. Third, the Spanish flu killed approximately 17 to 50 million people, and the lack of human response, overcrowding, and poor hygiene were key in promoting the spread and high mortality. Human behavior is the most important strategy for preventing the virus spread and we must adhere to proper precautions. This review will cover our current understanding of the pathology and treatment for COVID-19 and highlight similarities between past pandemics. By revisiting history, we hope to emphasize the importance of human behavior and innovative therapies as we wait for the development of a vaccine.

人类正在与一种快速传播的病毒——严重急性呼吸系统综合症冠状病毒 2 作斗争，它是 2019 年冠状病毒病或 COVID-19 的罪魁祸首。尽管在五月份重新开业后，阳性病例再次出现，但随着人们急切地从联邦政府规定的隔离区涌入美国各地的餐馆、酒吧和健身房，人们对这一流行病的心态正在发生转变。历史可以让我们了解过去，今天的大流行也不例外。如果没有可用的疫苗，1918 年西班牙流感大流行的三个教训可能会帮助我们对抗 COVID-19。首先，那些在第一波浪潮中幸存下来的人对第二波浪潮产生了免疫力，这凸显了基于被动免疫的治疗（如恢复期血浆和细胞疗法）的潜力。其次，COVID-19 的长期后果尚不清楚。缓慢进展的西班牙流感病例与以后生活中的细菌性肺炎和神经系统疾病有关，这强调了减少 COVID-19 传播的必要性。第三，西班牙流感导致大约 17 至 5000 万人死亡，人类反应不足、过度拥挤和卫生条件差是促进传播和高死亡率的关键。人类行为是防止病毒传播的最重要策略，我们必须坚持适当的预防措施。这篇综述将涵盖我们目前对 COVID-19 病理学和治疗的理解，并强调过去流行病之间的相似之处。通过回顾历史，我们希望在等待疫苗研发的过程中强调人类行为和创新疗法的重要性。