Disease Outbreaks Ebola Virus Disease Largest and longest

Disease Outbreaks

Ebola Virus Disease • Largest and longest outbreak occurred in 2014 in West Africa • Symptoms: Fever, muscle pain, diarrhea, vomiting, internal bleeding • Transmission: Direct contact with an infected person • 30 000 cases were reported; 12 000 people died in six countries.

Terms used to describe disease occurrence: Endemic: • The occurrence of disease cases is at a constant, stable amount within a geographic area. Epidemic: • The occurrence of disease cases exceeds the normal amount expected for a population in a geographic area. Outbreak: term used for an even smaller geographic area (i. e. , in a single community or in a particular nursing home)

Pandemic: • An epidemic that has spread over several countries or continents, or around the whole world. Was Ebola Virus Disease (EVD) an outbreak, epidemic or pandemic?

• Epidemics and pandemics can have both social and economic impacts on human populations (as well as environmental impacts). Refer to Fig. 1. 21 in your text. Classify each of the four cases as a social impact, an economic impact, or both. HIV has killed more than 25 million people since it was first identified in 1984. In just the first two decades of the 21 st century, more than 1 million people have died due to diseases suchs as SARS, H 1 N 1, measles, and typhoid. Some livestock animals can pass on diseases to people. In 2015, an outbreak of bird flu forced poultry producers to kill about 50 million chickens and turkeys. The price of eggs increased, and farmers lost millions of dollars. Sick days take their toll. Flu alone results in losses of half a billion dollars each year to the Canadian economy. Taking extra precautions, as well as concern about fear and panic, can lead governments to restrict travel as well as the importation of certain foods.

• It is possible to naturally build up immunity to pathogens over a longer period of time. • For example, European populations built up some immunity to measles and smallpox since 300 CE. • When Europeans came over to North America, large numbers of indigenous peoples died because they had never been exposed to the disease. (acquired immune response!)

Assignment: Go to the Assignment Tab on the Ribbon on the top of the Teams page and complete Assignment #1: Immune System and Infectious Disease Questions.