Járványok a 20. és 21. században.
Szeretnék egy áttekintést adni a 21. és 20. századik nagyobb járványokról. Mi volt a mostani vírus előtt?
First let’s clarify the difference between pandemic and epidemic – two English words used for ’járvány’ An epidemic is a disease that affects a large number of people within a community, population a region. A pandemic is an epidemic that has spread over multiple countries or continents.
The Zika fevercaused by the Brazilian Zika virus spread to other parts of South and North America resulting in over 1,5 million cases claiming approximately53 lives in 2015-16. While Zika did not make it to Europe – apart from a few isolated cases – it hit the headlines because of the approaching Rio de Janeiro Summer Olímpics and its particular danger to pregnant women and their fetuses. It spread mostly by the bite of an infected mosquito.
Ebola virus disease is a severe, often fatal illness affecting humans and other primates. The most serious Ebola outbreak ever took place between 2014 and 2016.The virus is transmitted to people from wild animals (such as fruit bats, porcupines and non-human primates) and then spreads in the human population through direct contact with the blood, secretions, organs or other bodily fluids of infected people, and with surfaces and materials (e.g. bedding, clothing) contaminated with these fluids. The average EVD case fatality rate is around 50%. outbreaks. The first EVD outbreaks occurred in remote villages in Central Africa, near tropical rainforests. The 2014–2016 outbreak in West Africa was the largest and most complex Ebola outbreak since the virus was first discovered in 1976. The course of the illness typically progresses from “dry” symptoms initially (such as fever, aches and pains, and fatigue), and then progresses to “wet” symptoms (such as diarrhea and vomiting) as the person becomes sicker.
First identified in Saudi Arabia the Middle East respiratory syndrome (MERS) was caused by a coronavirus that very much resembles the current one. nfection with MERS-CoV can cause severe disease resulting in high mortality. Humans are infected with MERS-CoV from direct or indirect contact with dromedaries. MERS-CoV has demonstrated the ability to transmit between humans. So far, the observed non-sustained human-to-human transmission has occurred mainly in health care settings
The 2009 swine flu pandemic was an influenza pandemic that lasted for about 19 months, from January 2009 to August 2010, and was the second of two pandemics involving H1N1 influenza virus (the first being the 1918–1920 Spanish flu pandemic). First described in April 2009, the virus appeared to be a new strain of H1N1, for which existing vaccines against seasonal flu provided little protection. Children had no preexisting immunity to the new strain but that adults, particularly those older than 60, had some degree of immunity.
The first pandemic of the 21st century also started from China. This was the SARS severe acute respiratory syndroem. SARS-CoV is thought to be an animal virus from an as-yet-uncertain animal reservoir, perhaps bats, that spread to other animals (civet cats). An epidemic of SARS affected 26 countries and resulted in more than 8000 cases in 2003. Since then, a small number of cases have occurred as a result of laboratory accidents or, possibly, through animal-to-human transmission (Guangdong, China).
Transmission of SARS-CoV is primarily from person to person. It appears to have occurred mainly during the second week of illness, which corresponds to the peak of virus excretion in respiratory secretions and stool, and when cases with severe disease start to deteriorate clinically. Most cases of human-to-human transmission occurred in the health care setting, in the absence of adequate infection control precautions. Implementation of appropriate infection control practices brought the global outbreak to an end.
1981-to date: AIDS
By far the most deadly epidemic of modern times: according to UNAIDS some 32 million people around the world have died of the disease which affects the immune system and leaves people vulnerable to opportunistic infections. Today around 24.5 million people have access to retroviral drugs which when taken regularly efficiently stop the illness in its tracks and heavily reduce the risk of contamination.
1968-1970: The Hong Kong flu
Around one million people died of this disease, according to the US Centers for Disease Control and Prevention (CDC).Transmitted around the world between mid-1968 and early 1970, it in particular killed many children. It first started in Hong Kong, spread through Asia and reached the United States in late 1968. After lying low for several months it then hit Europe in late 1969.For epidemic experts, this flu went down in history as the first of the modern era, due to the advent of high-speed air travel.
1957-1958: Asian flu
Around 1.1 million people died of Asian flu, according to the CDC. The pandemic hit in two aggressive waves. The virus first appeared in southern China in February 1957. Several months went by before it reached America and Europe.The disease, which results in serious lung complications, in particular affected the elderly.
1918-1919: Spanish flu
Spanish flu hit a large part of the world’s population in the wake of World War I, killing up to 50 million people, according to the CDC.Striking between September 1918 and April 1919, it is considered the most deadly in history over such a short period.Five times more people died of it than did in World War I. The first victims were recorded in the United States, before it spread to Europe and then around the world. Its mortality rate was estimated at more than 2.5 percent, according to the CDC.