As I flew home from Panama yesterday, with my yellow fever immunization document tucked away with my travel documents, I was confident that I was going home disease free. Even without the immunization, I really don't need to worry because yellow fever was virtually wiped out of the canal zone in Panama early the 20th century. But it used to be one of the top killers in that area. Many workers lost their lives to yellow fever while building the Panama canal.
Today there are 44 countries where you can find pockets of yellow fever. More than 200,000 people still catch the disease today; 30,000 of them die from it. It's pretty nasty.
Mosquitos transmit this viral disease. The first symptoms are fever, pain, extreme shivers, headache, and nausea. If those pass, you might be one of the lucky survivors, but you might be one of the 15% for whom fever returns, whose skin turn yellow, who bleed from the mouth, noses eyes or stomach, and whose kidneys stop working properly. If you are one of the unlucky ones, you are likely to die from the disease.
The yellow fever virus (arbovirus of flavivirus genus) infects monkeys as well as humans. Mosquitos can pick up the virus from a monkey and transmit it to other monkeys as well as to humans. There are lots of New World monkeys in Panama. Fortunately all the ones I saw during my trip looked pretty healthy!
Find out more from the World Health Organization.