Introduction
Sustainability of cities is one of the comprehensive approaches of planners, designers, and researchers in the study, research, and action. The importance of which is doubly felt in special critical situations. One of these cases is the spread of epidemic diseases, which causes many problems. Disruption of the normal process of individual and Social life, closure and stagnation of social, cultural, sports, and recreational activities, destruction of businesses, mental disorders caused by quarantine, inadequate living, and working spaces, and the impossibility of physical distance from the most important issues facing cities and communities.

Methodology
The main purpose of the study is "to provide a conceptual framework for a sustainable city against epidemics" and sub-objectives include "explaining urban issues and needs in the face of epidemics" and "assessing the sustainability of Tabriz market areas against coronary heart disease" Is the basis of the conceptual framework of the plan. Also, according to the mentioned Aims, the research question is: What are the requirements and strategies for the sustainability of urban tissues against epidemic diseases?
The present study is one of the quantitative-qualitative researches and is one of the applied studies. The method of this research will be studied and analyzed according to the nature of the research in the theoretical studies section with a descriptive-analytical method and interdisciplinary studies of opinions, ideas, and related views. So that by reviewing the relevant documents from the latest findings by library and documentary study method to summarize, analyze, and provide a conceptual framework.
Results and discussion
The results show that strengthening communication and virtual media to help each other, especially vulnerable groups of the epidemic; Government and public support for the needy; Promoting a culture compatible with epidemic lifestyle, promoting a lifestyle compatible with epidemic restrictions, diligence in holding rituals, and celebrating ceremonies virtually and social distancing from cyberspace and efficient smart infrastructure, face-to-face use of appropriate physical spaces with the observance of spacing Social, citizenship education through virtual and face-to-face, holding rituals online and in-person by observing health protocols in the epidemic period is very effective. Also in the design of cities and urban spaces, having open and semi-open spaces, public and semi-private to observe physical distance and private and semi-private spaces to meet the recreational and leisure needs of families in the quarantine limits, neighborhood self-sufficiency ژه and especially multi-purpose neighborhood centers in meeting the needs of residents and not referring to crowded centers, citizenship training in observing the limitations of epidemic control, having efficient access infrastructure (smart city infrastructure and proper bike and pedestrian routes), advance Finding sufficient space per capita in urban centers and poles (especially green space and public open space with the possibility of physical distance) is one of the most important strategies.
Conclusion
Sustainability has a comprehensive view of all social, cultural, economic, and spatial-physical dimensions of human life and space, which makes it possible to study a sustainable city in various fields, especially during epidemics. Space is one of the needs of human individual and collective life, which is the bedrock of human life in all times and activities. Space can have many positive and negative effects on human life and cause its desirability and satisfaction. Sustainability of the city and urban spaces in times of epidemic and related constraints can meet the needs and related issues. A sustainable city in social, cultural, economic, and spatial-physical dimensions is facing many emerging issues that require the adoption of appropriate measures and methods in urban planning and design and related measures. The most important strategies for urban resilience against epidemics are:
Special attention and planning should be paid to the vulnerable groups in order to provide them with livelihood and financial, health, and psychological support. The most important of these are slums, informal settlements, poor families, nursing homes, working, and street children, garbage collectors, peddlers, epidemic patients and their families, immigrants, seasonal workers, and female-headed households.
Adopt a lifestyle consistent with the limitations of epidemic control and pay attention to the consequences of inactivity and long-term presence at home during quarantine and provide creative methods (such as exercise at home and at work, etc.).
• Having public and semi-private open and semi-open spaces to observe physical distance and private and semi-private spaces, especially yards, terraces, and roofs to meet the recreational and leisure needs of families in quarantine restrictions, neighborhood self-sufficiency, and especially Multi-purpose neighborhood centers in meeting the needs of residents and not referring to crowded centers.
• Citizenship education and incentives to promote it in compliance with the limitations of epidemic control through various means (media, virtual networks, schools, universities, public spaces and neighborhoods, and parks)
• Ensuring efficient access infrastructure in neighborhoods, regions, and cities (smart city infrastructure and suitable bicycle, pedestrian, and horse routes)
• Predicting sufficient space per capita in urban design and redesign, especially in urban functional centers and poles (especially green and public open spaces with the possibility of physical distance).