The COVID-19 infection caused by severe acute respiratory syndrome
coronavirus 2 (SARS-CoV-2), progressed to a global pandemic and led to millions of
deaths worldwide over the years since its COVID-19 origin. Coronavirus transmission
is a zoonotic spillover, which means that virus transmission can occur from a vertebrate
animal to a human host. The CoV genome underwent continuous recombination and
evolution, which resulted in interspecies transmission and the virus' recurrent
emergence as a pandemic. The SARS-CoV-2 infection primarily results in respiratory
symptoms, like pneumonia, that range from mild to severe in severity, along with
alveolar injury ultimately leading to acute respiratory distress syndrome (ARDS) and
death. This chapter outlines the SARS-CoV-2 transmission pathways, how the disease
spreads by infected people, and the consequences for the prevention and control of
infection, both inside and outside healthcare facilities. This section also covers modes
of transmission like horizontal, fomite, fecal-oral, nosocomial, and animal-to-human
transmission of SARS-CoV-2.
Keywords: COVID -19, Modes of transmission, SARS-CoV-2, Transmission cycle.
