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
What is Cold Urticaria? Cold urticaria is a skin reaction to the cold temperatures, in which red and itchy bumps appear on the skin. The intensity of the symptoms depends on the actual stimulus (cold weather, cold object etc.) but also from one patient to the other, ranging from minor to severe reactions.