Abstract

Communicable diseases, also known as infectious diseases, are illnesses caused by pathogens such as bacteria, viruses, fungi, and parasites. These diseases can spread from one person to another, either directly or indirectly, through various means including physical contact, contaminated food or water, and airborne droplets. The global impact of communicable diseases is profound, affecting millions of people annually and leading to significant morbidity and mortality. The pathogens responsible for communicable diseases come in various forms, each with unique transmission mechanisms. Bacteria, for instance, can cause illnesses such as tuberculosis and strep throat. Viruses, including influenza and HIV, lead to a range of conditions from the common cold to acquired immunodeficiency syndrome (AIDS). Fungal infections like candidiasis and parasitic diseases such as malaria also fall under the communicable disease category. Communicable diseases pose a significant challenge to global health. The World Health Organization (WHO) reports that such diseases are responsible for a substantial portion of global morbidity and mortality, particularly in low- and middle-income countries. The prevalence of communicable diseases is influenced by various factors including socioeconomic conditions, healthcare infrastructure, and public health policies.