Africa and the Atlantic Slave Trade. Before the 16th century, Europeans were not deeply involved in slave trading on the West African coast. However, there was some movement of African labour to Madeira and the Canary Islands by the early Portuguese explorers from 1470 onwards.
urticaria is not contagious you cannot pass it on to another person acute urticaria or acute hives when symptoms last less than 6 weeks it is called acute urticaria this is by far the most common type 25 % of people with acute urticaria also have angioedema swelling in the deeper layers of skin
You can be contagious from a few days up to two weeks or more, depending on which virus is causing your stomach flu (gastroenteritis).A number of viruses can cause gastroenteritis, including noroviruses and rotaviruses.The contagious period â the time during which a sick person can give the illness to others â is slightly different for each virus. 1  Norovirus.2  With norovirus â the most common cause of viral gastroenteritis in adults and children â you're contagious from the moment you begin to feel ill. number of viruses can cause gastroenteritis, including noroviruses and rotaviruses. The contagious period â the time during which a sick person can give the illness to others â is slightly different for each virus.