infection: Quick Facts

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World Health Organization

Color-enhanced microscope image showing numerous rod-shaped EHEC (E. coli) bacteria in pink on a textured yellowish surface.

Infographic showing estimated lives saved by childhood vaccinations worldwide from 1974 to 2024, with syringe-shaped bars for each disease. Measles tops the list at 93.71 million lives saved, followed by tetanus, whooping cough, and others, for a total of 153.84 million lives saved.

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infectious disease 6 Common Infections We Wish Never Existed What are the five ways infectious diseases can be spread?resistance carrier healthcare-associated infection direct transmission cyclic disease transmission opportunistic infection subclinical infection inflammation mental disorder cardiovascular disease nervous system disease digestive system disease nutritional disease childhood disease and disorder Plant disease respiratory disease human genetic disease

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Key People

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Leonard Colebrook

British medical researcher

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Heinz L. Fraenkel-Conrat

American biochemist

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