Preface

The COVID-19 pandemic has had myriad negative consequences around the globe. As of December 2022, there were 649,038,437 confirmed cases and 6,645,812 deaths worldwide. In Mexico, for example, there were 7,222,611 confirmed cases and 331,030 deaths [1].

The pandemic caused much fear, especially when secondary effects such as anosmia, dysgeusia, coagulation disorders, stroke, and cardiovascular problems that could lead to death began to be reported. In addition, there were reports of other sequelae such as pulmonary fibrosis, mental disorders, kidney problems, and more. This book provides a comprehensive overview of post-COVID effects on human health. Chapter 1 discusses treatments of COVID-19 and vaccines and examines their relationship to post-COVID sequelae. Chapter 2 examines Multisystemic Inflammatory Syndrome in children (MIS-c); it was very important in children with COVID-19. Post-COVID-19 stroke and rehabilitation were reviewed in Chapter 3.

The relationship between mental health and COVID-19 was reviewed and analysed in Chapter 4; it is suggested that mental health in the aftermath of the pandemic should be closely monitored. This issue was very important because the threat of being infected by SARS-CoV-2 generated a lot of fear in the world population. In addition to those who were infected, anguish and emotional disorders were generated due to the fear of facing a serious illness or death and in those around them, isolation and not performing the usual tasks also cause disturbances in mental health. Chapter 5 reviewed hydro electrolytic alterations that could be mediated by antidiuretic hormones. Chapter 6 presents the effects on mental health in oncology mental health works, and finally, chapter 7 reviews Covid-19 in Mexico, where there were high numbers of cases as well as deaths due to the virus.

I wish to thank the staff at IntechOpen, especially the Publishing Process Manager, Ms. Dolores Kuzelj, for her excellent support throughout the publication process. I am also grateful to the contributing authors for their excellent chapters.

> **Dr. Nicolas Padilla-Raygoza** Department of Research and Technological Development, Directorate of Teaching and Research, Institute of Public Health from Guanajuato State, Guanajuato, Mexico
