Why are viruses causing such an impact on humans in recent times?
H1N1, MERS, swine flu, Zika, chikungunya, one more virus with a strange name always appears to be popping up, threatening to grow into a pandemic.
Quite a few of the pathogens that trigger deadly outbreaks are not entirely new viruses. Some of them have evolved with us for centuries. Nowadays, these viruses can travel and infect around the globe with larger efficiency and shorter times than ever before and when they appear suddenly in new areas, they take health systems, doctors and our immune systems by surprise.
We are able to transport anything farther than and at greater speeds and volumes than in any other period in the past. People these days are also more …show more content…
Globally, approximately 600 million people reside in endemic areas. The number of cases of yellow fever has been increasing drastically since the 80’s. This is thought to be due to more people living in cities, less people being immune, people moving frequently and of course, climate change. Originating in Africa, it spread to South America in the 17th century via the slave trade. Since then, numerous major occurrences of the disease have occurred in Europe, Africa and the Americas. Yellow fever was seen as one of the most dangerous infectious diseases in the 18th and 19th centuries. This disease is still around to this day and has caused an epidemic throughout the first half of this year. From February 2016 – June 2016, this virus had occurred in Africa as expected, but also in China. This is most probably due to people from Africa who travelled to china with the …show more content…
infection: Yellow fever arises after a period of three to six days of incubation in the host. Only a minor infection with headache, fever, back pain, chills, muscle pain, fatigue, loss of appetite, vomiting and nausea occur in most cases. The illness only lasts three to four days in these cases.
2. remission: Fever and most other symptoms disappear. Most people recover at this stage, others may get worse within 24 hours.
3. Intoxication: Fifteen percent of people infected go into a toxic phase of yellow fever with chronic fever, together with liver damage that induces jaundice and abdominal pain. Kidney failure, delirium and hiccups may also occur. Bleeding in the eyes, mouth and gastrointestinal tract cause vomiting of blood, that’s how the Spanish name for this virus became, vomito negro ("black vomit").
Twenty to fifty percent of toxic phases become fatal, causing the fatality rate of yellow fever disease to be between 3 – 7.5% before the toxic phase and over 50% after the toxic phase has struck. Surviving yellow fever infection affords a person with permanent immunity and generally there is only temporary organ