Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of the novel respiratory disease COVID-19, has reached pandemic status and presents a wide range of manifestations of diverse magnitude, including fever, cough, shortness of breath, and damage to vital organs, such as the heart, lung, kidney, and brain. Normally, older individuals and those with underlying health issues are more at risk. However, about 40% of COVID-19 positive individuals are asymptomatic. This review aims to identify suggested mechanisms of diverse manifestations of COVID-19. Studies suggest that T cell-mediated immunity and specific and/or nonspecific immunity from other vaccines could protect against SARS-CoV-2. The potential role of cross-reacting antibodies to coronaviruses that cause the common cold, mumps virus, polio virus, and pneumococcal bacteria are also suggested to help protect against COVID-19. Decreased production of Type I interferons (IFN-α and IFN-β) could also be linked to COVID-19 manifestations. Several studies suggest that ACE2 cell membrane receptors are involved in SARS-CoV-2 infection. However, the relationship between an abundance of ACE2 receptors and the infectivity of the virus is unknown. Unlocking these manifestation mysteries could be crucial as this could help researchers better understand the virulence, pathology, and immune responses associated with SARS-CoV-2, leading to the development of effective therapies and treatment plans.

Mpox, a zoonotic viral disease, has emerged as a global concern due to outbreaks in both endemic and non-endemic regions in 2022. Rodents, including African squirrels and Gambian pouched rats, are suspected key reservoirs, with human infections occurring through direct contact with infected animals or bushmeat consumption. Previously confined to rural Africa, mpox has spread via international travel and the exotic pet trade. Human-to-human transmission occurs mainly via respiratory droplets and direct contact with bodily fluids or lesions. The virus has a double-stranded DNA genome within a lipid envelope. Despite lower mutation rates in DNA viruses, mpox has developed mutations, particularly in genes like F8L, G9R, and F13L, facilitating viral replication and immune evasion. The virus targets immune cells such as monocytes and macrophages, weakening host defenses and prolonging infection. Immunocompromised individuals are at higher risk of severe complications. Although generally self-limiting, severe cases may require antiviral treatment. This article briefly summarizes the therapeutic and preventive strategies, and public health measures to combat zoonotic threats.