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Viruses were expected to be small, but the range of sizes came as a surprise. Some were only a little smaller than the smallest known bacteria, and the smaller viruses were of similar sizes to complex organic molecules. [14] In 1935, Wendell Stanley examined the tobacco mosaic virus and found it was mostly made of protein. [15]
Vaccination was made compulsory in England and Wales by the Vaccination Act 1853 (16 & 17 Vict. c. 100), and parents could be fined £1 if their children were not vaccinated before they were three months of age. The law was not adequately enforced, and the system for providing vaccinations, unchanged since 1840, was ineffective.
Paleovirology is the study of viruses that existed in the past but are now extinct. In general, viruses cannot leave behind physical fossils, [1] therefore indirect evidence is used to reconstruct the past. For example, viruses can cause evolution of their hosts, and the signatures of that evolution can be found and interpreted in the present ...
Western Hemisphere populations were ravaged mostly by smallpox, but also typhus, measles, influenza, bubonic plague, cholera, malaria, tuberculosis, mumps, yellow fever, and pertussis. The lack of written records in many places and the destruction of many native societies by disease, war, and colonization make estimates uncertain.
The history of biology traces the study of the living world from ancient to modern times. Although the concept of biology as a single coherent field arose in the 19th century, the biological sciences emerged from traditions of medicine and natural history reaching back to Ayurveda, ancient Egyptian medicine and the works of Aristotle, Theophrastus and Galen in the ancient Greco-Roman world.
Epidemics of the 19th century were faced without the medical advances that made 20th-century epidemics much rarer and less lethal. Micro-organisms (viruses and bacteria) had been discovered in the 18th century, but it was not until the late 19th century that the experiments of Lazzaro Spallanzani and Louis Pasteur disproved spontaneous generation conclusively, allowing germ theory and Robert ...
The findings, published in a series of articles in Current Archaeology, come from one of the largest ancient DNA projects in Europe involving 460 people who were buried in graves between 200AD and ...
Outbreaks were particularly severe in communities suffering from food scarcity. The epidemics of fevers and respiratory illness eventually became referred to as the new sickness in England, [2] new acquaintance [9] in Scotland, and coqueluche or simply catarrh by medical historians [17] in the rest of Europe.