Saha Sangeeta, Samanta Guruprasad, Nieto Juan J
Department of Mathematics, Indian Institute of Engineering Science and Technology, Shibpur, Howrah 711103, India.
Instituto de Matemáticas, Universidade de Santiago de Compostela, Santiago de Compostela 15782, Spain.
Math Comput Simul. 2022 Oct;200:285-314. doi: 10.1016/j.matcom.2022.04.025. Epub 2022 Apr 30.
The first COVID-19 case was reported at Wuhan in China at the end of December 2019 but till today the virus has caused millions of deaths worldwide. Governments of each country, observing the severity, took non-pharmaceutical interventions from the very beginning to break the chain of higher transmission. Fortunately, vaccines are available now in most countries and people are asked to take recommended vaccines as precautionary measures. In this work, an epidemiological model on COVID-19 is proposed where people from the susceptible and asymptomatically infected phase move to the vaccinated class after a full two-dose vaccination. The overall analysis says that the disease transmission rate from symptomatically infected people is most sensitive on the disease prevalence. Moreover, better disease control can be achieved by vaccination of the susceptible class. In the later part of the work, a corresponding optimal control problem is considered where maintaining social distancing and vaccination procedure change with time. The result says that even in absence of social distancing, only the vaccination to people can significantly reduce the overall infected population. From the analysis, it is observed that maintaining physical distancing and taking vaccines at an early stage decreases the infection level significantly in the environment by reducing the probability of becoming infected.
2019年12月底，中国武汉报告了首例新冠病毒病例，但截至目前，该病毒已在全球造成数百万人死亡。各国政府鉴于其严重性，从一开始就采取了非药物干预措施，以阻断更高传播链。幸运的是，现在大多数国家都有疫苗可供使用，人们被要求接种推荐的疫苗作为预防措施。在这项工作中，提出了一个关于新冠病毒的流行病学模型，处于易感和无症状感染阶段的人在完成两剂疫苗接种后进入接种疫苗类别。总体分析表明，有症状感染者的疾病传播率对疾病流行率最为敏感。此外，通过对易感人群进行疫苗接种可以实现更好的疾病控制。在工作的后期，考虑了一个相应的最优控制问题，其中保持社交距离和疫苗接种程序随时间变化。结果表明，即使没有社交距离，仅对人们进行疫苗接种也能显著减少总体感染人群。从分析中可以看出，保持身体距离并在早期接种疫苗，通过降低感染概率，可显著降低环境中的感染水平。
