There isn't one single "deadliest" virus, as it depends on the metric: Rabies is nearly 100% fatal if symptoms show (highest case fatality rate), while viruses like Ebola (Zaire strain) and Marburg have extremely high fatality rates (up to 90%) during outbreaks. Historically, viruses causing pandemics like the 1918 Flu or HIV/AIDS have caused massive death tolls, but Rabies has the highest fatality once symptoms appear.
Rabies virus has a characteristic bullet-shaped virion structure. Rabies virus infection in mammals is nearly 100% fatal if left untreated.
In 2025, a resurgence of chikungunya virus (CHIKV) disease was noted in a number of countries, including some that had not reported substantial case numbers in recent years.
Marburg virus disease (MVD), formerly known as Marburg haemorrhagic fever, is a severe, often fatal illness in humans. The average MVD case fatality rate is around 50%. Case fatality rates have varied from 24% to 88% in past outbreaks. Early supportive care with rehydration, and symptomatic treatment improves survival.
7 Deadliest Diseases in History: Where are they now?
The number one killer in the world is Cardiovascular Disease (CVD), also known as heart disease, which causes about one-third of all global deaths annually, killing millions each year and remaining the leading cause for the past two decades. Diseases like ischaemic heart disease (coronary artery disease) and stroke are major contributors, with COVID-19 temporarily disrupting trends but CVD consistently holding the top spot.
Both septicemic plague (blood infection) and pneumonic plague (lung infection) had a nearly 100% death rate if left untreated, with pneumonic plague being the most contagious form, spreading through airborne droplets and being rapidly fatal. Untreated bubonic plague (swollen lymph nodes) could also develop into these deadly forms, leading to high mortality.
He died on Dec. 6, 2013, at age 2, and the domino effect of his illness has spiraled into the outbreak currently ravaging three nations in West Africa. His name was Emile Ouamouno. Emile's 3-year-old sister, his mother and his grandmother all died by January, leaving his father behind.
Ebola virus infection is slightly more virulent than Marburg virus infection. Ebola virus isolates have been differentiated into 5 species: Zaire Ebola virus. Sudan Ebola virus.
It's a life-threatening virus that can cause lasting health effects. But more and more people are surviving Ebola with advances in vaccines to prevent its transmission and better treatments. If you're at risk of encountering Ebola, there are steps you can take to protect yourself and prevent the spread.
The next pandemic is not a case of if, but when. This could be caused by a coronavirus related to COVID-19, such as the even deadlier Severe Acute Respiratory Syndrome (SARS) or Middle Eastern Respiratory Syndrome (MERS), or a new coronavirus lurking somewhere in the world that could soon 'jump' into people.
prepared and cooked poultry and eggs are safe to eat.
Called FLiRT due to the technical names for its spike protein mutations, which include the letters F, L, R and T, FLiRT is a subvariant of last winter's dominant strain Omicron, and is driving this summer's COVID wave.
A pandemic may have been responsible for the widespread collapse of the dinosaurs. More than a hundred hypotheses have been linked to the extinction of the dinosaurs.
Abstract. We recently described Megavirus chilensis, a giant virus isolated off the coast of Chile, also replicating in fresh water acanthamoeba. Its 1,259,197-bp genome encodes 1,120 proteins and is the largest known viral genome.
The SARS-CoV-2 virus that causes Covid-19 illness surpassed a grim milestone in early July. The number of deaths from Covid-19 in Africa—more than 11,950—exceeded the total number of people who died during the largest-ever Ebola outbreak in West Africa, according to the World Health Organization.
Marburg virus disease. Marburg hemorrhagic fever is a severe and highly fatal disease caused by a virus from the same family as the one that causes Ebola hemorrhagic fever. Both diseases are rare, but can cause dramatic outbreaks with high fatality.
Some viral infections can be cured, but others cause chronic conditions that cannot yet be cured. Antivirals can eliminate some viruses like flu and Ebola. Viral infections like HIV, hepatitis, and herpes are chronic and antivirals cannot get rid of these viruses once you have them in your body.
Symptoms of Ebola include: fever, headache, joint and muscle pain, diarrhea, vomiting, stomach pain, lack of appetite and abnormal bleeding. These symptoms are not specific to Ebola and are often seen with other illnesses.
On 11 March 2015, a UK military health worker contracted the disease in Sierra Leone while volunteering as a nurse.
Situation at a glance. On 1 December 2025, the Ministry of Health (MoH) of the Democratic Republic of the Congo (DRC) declared the end of the Ebola virus disease (EVD) outbreak which had been declared on 4 September 2025.
The film follows a tween boy at a water polo camp who soon finds himself the victim of a cruel tradition. The tradition is the rumor that he has a plague, an infectious disease that is contagious if the subject is not shunned. This functions as an allegory for isolation and exclusion.
The Heaviest Hitters
Symptoms usually develop two to six days after exposure. The best recovery happens if you are treated within 24 hours of developing symptoms. You'll probably feel better after one to two weeks. However, untreated bubonic plague can be fatal.