October 13:
(1) (1821) German physician, anthropologist, and pathologist Rudolf Virchow is born. He is known for advancing public health, and for helping to discredit humourism (a discredited branch of medicine that states that excess or deficiency of any of four distinct bodily fluids, or humours, causes disease).
(2) (1919) Sri Lankan Tamil physician, zoologist, and academic Ragunathar Kanagasuntheram is born. He worked at multiple universities as a professor of anatomy, biology and dean of the faculty of medicine.
(3) 1976 – The first electron micrograph of an Ebola viral particle is obtained by the CDC.