Since the dawn of human history, various infectious diseases have appeared in different time periods. The effects of each infection on humans, their rates of spread and the processes of containment have differed. The COVID-19 pandemic that emerged in December 2019 has spread rapidly all over the world and still exists today. Within the scope of this study, it is aimed to draw attention to important infectious diseases which are neglected as a result of the negative impact of the COVID-19 pandemic on the health sector. The information on the effects of the COVID-19 pandemic on the diagnosis and treatment processes of the most common and most fatal diseases in the world such as tuberculosis, hepatitis, HIV,iInfluenza and malaria has been compiled from relevant literature. There is concern that the COVID-19 pandemic will cause short-term disruptions in the diagnosis and treatment processes of these diseases, an increase in the burden of these infections in the long term and disruption of control strategies.