Table 1.

Summarized information discussed extensively in this review.

Organism	Group and Virology		Epidemiology		Pathogenesis		Management and Treatment
RNA Viruses	Zika; ss, + strand RNA genome encoding 7 non-structural proteins and 3 structural proteins		Started in Brazil in 2007; on decline since 2019. More than 200,000 cases		Transmitted by mosquito bites or sexual intercourse; humans – incidental hosts. Shed in the urine during illness		No proper antiviral or vaccine available; prevention of mosquito bites, awareness and knowledge of the disease practiced
	Ebola; ss, - strand RNA genome encoding structural and non-structural proteins		1st outbreak in Zaire in 1976; 2nd outbreak in Africa in 2014. On decline since 2019 but cases are still reported		Transmission by formite, aerosols or direct contact; no report through sexual intercourse. High rate of mortality		No antiviral or vaccine available; ringworm vaccine found to be effective. Preventive measures and awareness programmes undertaken
	SARS		1st reported in China in 2002		Mostly like respiratory illness; inter (between man and camel) and intra-human transmission reported		Sanitization, masking, social distancing
	MERS		1st reported in Oman in 2012; 27 countries affected
	COVID-19		1st reported in China in 2003 during Spring festival (not severe). Next outbreak at same time in 2020 in China; major countries affected – cases still being reported		Mostly like respiratory illness; inter (between bat and man) and intra-human transmission reported through direct contact		Diagnosis through RT-PCR, CRISPR-based assays. Vaccines from Pfizer, Serum Institute of India, Bharat Biotech available – some more vaccines are underway
COVID Mutations
αβ variant in 2019–2020; origin China		Δ variant in 2020–2021; origin United Kingdom		Omicron variant in 2021–2022; origin South Africa		New variant (deltacron???) in 2022–2023??; origin?