List of Most Contagious Diseases: Quick Facts

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The Information Architects of Encyclopaedia Britannica

Photos

Infographic comparing the maximum basic reproduction numbers (R0) of various contagious diseases, using diagrams of a red contagious person spreading infection to multiple blue figures, with R0 values increasing from 2 for Ebola and influenza up to 18 for measles.

DTaP vaccine vial labeled for diphtheria, tetanus, and pertussis sits in front of a syringe, green medical gloves, and a disposable face mask.

Close-up of skin with numerous red, raised spots and blisters characteristic of a chickenpox rash.

Disinfection workers wearing masks and gloves spray and wipe down railings at Incheon International Airport in South Korea during the COVID-19 pandemic.

Rusty warning sign in French reading Attention Ebola, with instructions not to touch or handle animals found dead in the forest, displayed beside a road in Makoua, Congo.

Boxes of Ixiaro, Twinrix, and Rabipur vaccines are arranged on a table, showing their labels for Japanese encephalitis, hepatitis A and B, and rabies protection.

Influenza virus

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Topics

infectious disease pneumonia bloodborne disease cellulitis dysentery vulvitis sweating sickness zoonotic disease sexually transmitted disease List of Vaccine-Preventable Diseases parasitic disease