Viruses cause a number of diseases in eukaryotes. In humans, smallpox, the common cold, chickenpox, influenza, shingles, herpes, polio, rabies, Ebola, hanta fever, and AIDS are examples of viral diseases.Even some types of cancer -- though definitely not all -- have been linked to viruses.n humans, smallpox, the common cold, chickenpox, influenza, shingles, herpes, polio, rabies, Ebola, hanta fever, and AIDS are examples of viral diseases. Even some types of cancer -- though definitely not all -- have been linked to viruses.
Map of the fortifications. Located in Canada, the Ramparts of Quebec City are the only remaining fortified city walls in North America north of Mexico. The British began refortifying the existing walls, after they took Quebec City from the French in the Battle of the Plains of Abraham in 1759.
Quebec, French QuÃ©bec , Quebec cityÂ© Creatas/JupiterImagescity, port, and capital of Quebec province, Canada. One of the oldest cities in Canadaâhaving celebrated its 400th anniversary in 2008âQuebec city has a distinct old-world character and charm. It is the only remaining walled city in North America north of Mexico and was recognized as a UNESCO World Heritage site in 1985.