Aspects of epidemiology, pathology, virology, immunology, transmission, prevention, prognosis, diagnosis, and treatment of COVID-19 Pandemic: A narrative review

Sajjad Rahimi Pordanjani, Ali Hasanpour Dehkordi, Hasan Askarpour, Dariush Bastam, Mohammad Rafiee, Zaher Khazaei, Elaheh Mazaheri, Mohammad Hossein Vaziri, Siamak Sabour


Undoubtedly, COVID‑19 pandemic is one of the largest pandemics and one of the biggest international challenges for health‑care system of various countries in the world. This is a narrative review study based on the studies published related with different aspects of COVID‑19. The highest numbers of active cases are in the USA, Brazil, India, Russia, South Africa, as well as Colombia and the disease surveillance system must operate more quickly, timely, effectively, and sensitively in these countries. What is clear is that the SARS‑CoV‑2 basic reproduction number is significantly higher than one and its transmission power is extremely high. In general, it can be stated that mortality and fatality risk due to COVID‑19 in men, age increase, severity of disease, systemic disease, as well as inadequate access to the sufficient health‑care services will increase. There is currently no specific treatment and effective vaccine for COVID‑19. The novel coronavirus pandemic is more consistent with the epidemiological triangle model, which emphasizes that the disease is the result of the interaction of three factors of host, agent, and environment. Therefore, prevention and treatment activities should focus on cutting the virus transmission chain. The main way to deal with viral epidemics is prevention. The emerging of this ruthless virus has once again reminded us that communicable diseases should never be underestimated and forgotten. Considering the rapid transmission of COVID‑19, the health‑care authorities and workers should consider timely detection and safeguards to prevent the transmission to healthy individuals.


COVID‑19; epidemiology; infectious; narrative review; pandemics

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