Covid-19: How did the past outbreaks of deadly viruses end?
Before the Covid-19 epidemic, other viruses such as Ebola or the H1N1 influenza marked the history of the 21st century in spectacular fashion. But how did they end?
Ebola, SARS, H1N1 flu. These viruses, which cause deadly epidemics, have one thing in common: they have marked the history of the 21st century. Since December, Covid-19 has expanded this list. For now, no treatment or vaccine has yet been found to contain the epidemic, even with the international scientific community mobilized. But how were past epidemics stopped?
Ebola in 2013
The Ebola virus was first identified in 1976, but it was in 2013 that it caused a major epidemic in West Africa, resulting in 11,300 deaths. Although there is still no specific treatment for this disease, the epidemic has been contained thanks to restrictive measures. More effective measures than in the case of Covid-19, because the transmission of Ebola occurs only by human contact and not by aerosol. However, the virus saw a resurgence in 2018 in the Democratic Republic of the Congo, where it caused more than 2,200 deaths.
MERS in 2012
Middle East respiratory syndrome (MERS) occurred in 2012 in Saudi Arabia. Bats are believed to be the natural reservoir of the virus, but the intermediate host that would have transmitted it to humans is the dromedary. The Mers epidemic has affected more than 1,200 people and left almost 450 dead. Here again there is no treatment, but the spread of the virus has been contained thanks to restrictive measures, which consist of applying barrier gestures, as well as avoiding, in the Middle East, contact with people. patients and dromedaries.
Influenza H1N1 in 2009
The H1N1 flu first appeared in 2009 and claimed 18,500 lives worldwide according to the World Health Organization (WHO). A figure questioned by a study published in The Lancet Infectious Disesase, which estimates the number of deaths between 151,700 and 575,400.
The virus strain responsible for the disease was quickly isolated, which allowed the development of a vaccine, available a few months after the start of the epidemic. Vaccination has helped stop the epidemic, although the virus continues to circulate each winter.
Health officials said last April that the coronavirus responsible for Covid-19 was ten times more deadly than the virus that caused the H1N1 flu.
SARS in 2002
The severe acute respiratory syndrome (SARS) epidemic first appeared in China in 2002. The disease, which causes an atypical lung disease, is caused by SARS-CoV, a virus that belongs to the coronavirus family. Animals are believed to be the source of this virus - it is believed to have passed from bats to masked palm civets, which then passed on to humans.
In an attempt to stop the spread of the virus, containment and hygiene measures have been implemented in China. SARS affected more than 8,000 people worldwide and killed nearly 800 people, but was contained in the spring of 2003, thanks to isolation and quarantine measures.
Closing the markets where animals causing the virus were sold also helped slow its spread. "The epidemic ended quickly when we managed to stop the transmission from animals to humans", explains Frédéric Tangy, director of the Laboratory for Vaccine Innovation at the Institut Pasteur.