population (n.) 1610s, “whole number of inhabitants in a country, state, county, town, etc,” from Late Latin populationem (nominative populatio) “a people; a multitude,” as if from Latin populus “a people” (see people (n.)).

1a : the whole number of people or inhabitants in a country or region. b : the total of individuals occupying an area or making up a whole.

Viruses are living organisms that cannot replicate without a host cell. They are considered the most abundant biological entity on the planet. Diseases caused by viruses include rabies, herpes, and Ebola. There is no cure for a virus, but vaccination can prevent them from spreading.

In the summer of 1920, the Bubonic plague arrived on Galveston Island. The infectious disease that had killed large portions of the European population struck fear in residents and challenged scientists in the Texas port city 100 years ago.

The Great Plague of Marseille was the last major outbreak of bubonic plague in western Europe. Arriving in Marseille, France in 1720, the disease killed a total of 100,000 people: 50,000 in the city during the next two years and another 50,000 to the north in surrounding provinces and towns.

Plague repeatedly struck the cities of North Africa. Algiers lost 30,000–50,000 to it in 1620–21, and again in 1654–57, 1665, 1691, and 1740–42. Plague remained a major event in Ottoman society until the second quarter of the 19th century.

The Black Death was an epidemic of bubonic plague, a disease caused by the bacterium Yersinia pestis that circulates among wild rodents where they live in great numbers and density.

Plague is divided into three main types — bubonic, septicemic and pneumonic — depending on which part of your body is involved.