Types of the most dangerous viruses

Viruses transmitted primarily through the air

Orthomyxoviruses
enveloped viruses with single-stranded (-)RNA gene
Coronaviruses
enveloped viruses with a single-stranded (+)RNA gene
Paramyxoviruses
enveloped viruses with single-stranded (-)RNA gene
Influenza A
HxNx
Corona
HCOV
RhinoŠ
HRV
Rep. Sinc.
RSV
Metapneumo
HMPV
parainflu
HPIV
Measles
MEV
Nipah
NIV
Hendra
HEV
Newcastle
NDV

Viruses transmitted primarily through biofluids

Filoviruses
enveloped viruses with single-stranded (-)RNA gene

Retroviruses
enveloped viruses with a double-stranded (+)RNA gene
Picornaviruses
non-enveloped viruses with a single-stranded (+)RNA gene
Ebola
EBOV
Marburg
MARV
HIV 1
HIV1
Rhino
HRV
Entero
EV71
Hepatitis B
HBV
Coxsackie
CV
Polio
EV/POV

Viruses transmitted primarily through the blood

Flaviviruses
enveloped viruses with a single-stranded (+)RNA gene
Hepatitis C
HCV
Dengue 2
DENV2
Zika
ZIKV
West. Nile
WNV
Tick-borne encephalitis
TBVE
Japanese encephalitis
JEV

The colors from red to yellow here indicate viruses, the chances of which to create an epidemic are subjectively assessed from maximum to minimum. The list is incomplete, because several more viruses known to virologists can unexpectedly cause an epidemic. And we know even less about the means of combating them than against Ebola, Hendra, Newcastle or Marburg.