infectious disease: Quick Facts

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Facts

Also Known As	contagious disease • communicable disease

Photos and Videos

Diagram showing the West Nile virus transmission cycle: a mosquito bites an infected bird (the primary reservoir host), then transmits the virus to humans or horses (incidental hosts) through subsequent bites.

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.

MRSA and neutrophil

Epidemic typhus and Rickettsia prowazekii

Doctors Hilary Koprowski and Herald R. Cox in lab coats sit at a desk covered with papers, discussing documents related to rabies vaccine research.

Ethnic Uzbek refugees from Kyrgyzstan

Illustration of Clostridium tetani bacteria showing rod-shaped cells with round red spores at one end, scattered on a pale background.

Diagram showing a microscope with a magnified view of a large, rod-shaped bacterium next to a much smaller, round virus particle.

Why is it so hard to fight tuberculosis?

How did the polio vaccine change the world?

Why don't flu shots always work?

Gloved hands draw liquid from a vial into a syringe, overlaid on a digitally colored microscopic image of a virus with round particles in clusters.

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Topics

prodomal period fecal-oral route cryptosporidiosis fungal infection Picardy sweat operative sepsis balanitis adenoiditis List of Vaccine-Preventable Diseases zoonotic disease cardiovascular disease mental disorder nutritional disease childhood disease and disorder blood disease eye disease renal system disease immune system disorder speech disorder reproductive system disease

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