something that causes people to leave their country.
Yellow fever is an acute viral infection transmitted by mosquitoes in tropical sub-Saharan Africa and in the rainforests of tropical South America. Risk to travelers is very low, but high death rates may occur in unvaccinated travelers. Vaccination is about 100% protective in healthy travelers; however, no treatment for the disease exists
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Yellow fever (YF), a viral infection that occurs in tropical sub-Saharan Africa and the rainforests of tropical South America, is acquired through the bite of an infected mosquito.
Risk is low to very low in travelers and depends on the time of year and itinerary. Risk is 10 times greater in Africa than it is in South America.
Symptoms include fever, chills, and muscle aches, which may progress to vomiting, upper abdominal pain, and bleeding.
Consequences of infection in unvaccinated travelers include mental confusion, coma, shock, and multiorgan failure. Death may occur in up to 90% of those infected.
Prevention includes wearing long sleeves and long pants as well as observing personal protective measures against mosquito bites.
YF vaccine is given as a single dose at least 10 days prior to travel (for personal protection or to meet an entry requirement). Some YF-free countries may require vaccination only for travelers coming from another country with risk of YF transmission.
Vaccine side effects are most commonly injection-site reactions. Serious side effects are rare but may include brain inflammation in young children, neurological reactions, and multiple organ dysfunction (first time vaccinees only, mainly persons 60 years and older).
Duration of vaccine protection is long term; a booster dose for personal protection is recommended every 10 years only for persons who will be visiting a high-risk area, travel frequently to risk areas, or may have had an inadequate response to a previous YF vaccination.
The division of Germany into military zones
The answer is A) He developed new methods of steel production.
