After a virus almost wiped out humanity, humans have relied on technology to be their guard and savior. Even going to greater lengths, by programming and releasing many gadgets and cameras among devices, to keep an eye on every single member of society. Some members of this society are even starting to fight against these eyes put over them, even more so after a mysterious murder takes place and no camera records were found. Mio Tsuzuki, a girl that has learned how to bypass these cameras, asks Hazuki Makino to join her and Ayumi Kono as they go into the rabbit hole and find out the truth behind this case.

The first series to start our list, we have an interesting perspective of the consequences of a deadly virus ripping through humanity. As we’ll see throughout this list, humans should never be counted out when it comes to adjusting and bringing their best game to fight against any kind of enemy. In this case, society turned to technology, not only to find a cure but beyond that. Here we see a society that has overused their helping hand and now it has evolved and been established as an oppressive tool of social manipulation. We’ve got to wonder, how far will people go in order to keep every variable in the equation under control? This series helps put things in perspective and it’s a great start as our number ten.

When a strange virus suddenly appears on earth, scientists start to research in order to counterattack its effects on people. With this virus in particular however, there seems to be no way to fight it and as a result, a 100% death rate is certain to whoever becomes infected. As years go by, a theory starts to earn more credibility. The virus might have come from Mars and with this theory, it’s not only given the name Alien Engine Virus (AE Virus for short) but also a series of field trips to Mars are planned to search for a vaccine. What they find in Mars though will be only the beginning of a nightmare.

While the main story follows Akari Hizamaru and the rest of the crew on their way to Mars to collect some samples or Terra Formars test subjects, the virus becomes the origin of this story. As lethal as it is, no victim figures are announced or assumed, but needless to say, it must have been a big number for UNASA to decide to start researching about it. A great series with a great deadly virus to start our list!

How far would you go in order to gain and keep power in the world? Many countries and groups have their own agenda as they move forward in their fight for what they would consider a “better tomorrow”. Such is the case for Snakes, a terrorist group whose leader, Alphard Alshaya attempts to use one of the most dangerous biological weapons, the Ua Virus. Used for an attack in the city of Shibuya two years ago, the virus causes bleeding from all parts of the body except from bone and skeletal muscle. Caught in the middle of their actions is the duo of Minoru and Maria, a couple of journalists who happened to cross paths with the terrorist group’s actions. Lucky for them, the mercenary and archenemy of Snake, Canaan makes her appearance to save her old friend Maria. Together, they will try and put an end to Snake and the looming bio-war before it spreads around the world.

This series has a particular characteristic that makes it stand out from the rest. The virus in this series not only has an origin story but also has ulterior motive of creation, which deepens the roots of chemical warfare between a different set of factions even more. When it comes to the virus itself, due to its use, instead of a pandemic rise among the world, we see a series of sudden outbreaks that will cause the death of a few in a matter of hours. While this is not the easiest virus to catch, it most certainly ranks high among our top ten contenders.

The city of Rondo, filled with its dull citizens and boring streets, make for one small “paradise” city, at least according to detective Re-l. After a global catastrophe doomed the planet beyond recognition, the only places where “life” can be found is within Rondo’s walls. Nevertheless, technology never stops progressing, since we can see in this dystopian future the creation of “AutoReivs”, humanoid-like creatures that assist humans in their everyday needs. This balance gets altered suddenly however with the appearance of the “Cogito Virus”, a virus that grants them a consciousness. This wouldn’t be a problem but ever since the appearance of the virus, more and more AutoReivs have been involved in the crime scenes of different murders. In the end, it’s up to Re-l and her AutoReiv “Iggy” to uncover the mysteries behind these strange cases.

Ergo Proxy mixes a cyberpunk tone with a mystery vibe around the edges of its plot. You might be thinking that it’s a bit strange we talk about a virus that doesn’t affect humans directly or spreads like a disease but the “Cogito Virus” has a unique feature that makes it more than a great fit to our list. The “Cogito Virus” doesn’t follow a certain pattern, which means any AutoReiv could get it at any given moment and also, it could potentially turn a well-known, trustworthy companion into your murderer. Silent and definitely deadly, Ergo Proxy’s “Cogito Virus” earns a spot in our list.

Shuu Ouma is a student that has gone through many rough experiences. For example, The loss of his mother, new marriage of his father and above all else, living through the worst years of his native country, Japan. Ten years ago, the “Apocalypse Virus” surfaced and started spreading throughout the country, turning skin into a crystal-like solid, paralyzing and eventually killing its host. Nevertheless, as time moved forward, the country was taken over by GHQ, an association of countries created by the UN to help the Japanese people to have order restored. Not all is peace in Japan, however, as Funeral Parlor, a resistance group created to liberate the country of GHQ’s grasp, will do anything in their power to succeed. If everything goes according to their plan, Gai Tsutsugami will have the last laugh.

The “Apocalypse” Virus earns a spot in our list due to its fast reaction to kill its host and also due to the sheer number of casualties. A virus that can bring such chaos to a country in a matter of days is enough to send a shiver down the spine of anybody who could become infected by it. However, unlike other viruses on this list, a “derivation” of the “Apocalypse” virus was created and named the Void Genome, which is a “weaponized” modification of the “Apocalypse” virus. It’s already enough when the virus alone kills too many innocent people but, turning it into a weapon? May god have mercy on their souls!

Life on Earth was going the way you would expect. Your everyday events wouldn’t have made anybody turn their heads or pay any more attention to them than their own personal agenda. That was until the Medusa Virus hit the world. This virus petrifies its host after one to two months of incubation and has a 100% fatality rate. Needless to say, thanks to the havoc created by it among society, people even become terrified to go on with their day by day errands and risk acquiring this virus. After years of research, Venus Gate announces the Cold Sleep experiment which allows hosts to sleep until an antidote is discovered. With only 160 possible candidates, these people start their process into the experiment; thing is, the time in this state could be for even longer than 100 years. It’s said that hope is the last thing you lose in despair, but how long can hope withstand the hands of time?

The Medusa virus might not be worse than other viruses in this list but what King of Thorn brings to the table is how this virus affects society from a different perspective. In this film, we’re able to see how our present world would react to a virus outbreak in a much more business-oriented, media-covered and political way. It also makes us comprehend how ready we are or not to face a global pandemic outbreak. From one to two months left to live after being infected and then a 12 hour progressive paralysis, this virus will haunt you silently without you being able to fight it, making exposure a frightening experience.

The world was never the same after the Kabane started to appear throughout the land. Emerging from a mysterious virus, these monstrous zombie-like creatures will hunt down any other healthy being and kill them. Doing so, not only has brought pain and despair to all people, but also spreads the virus even more, making this a vicious cycle of death. Not all hope is lost, though, as humanity, in their never-changing adaptability, were able to rearrange roads and cities, transporting people and supplies on enormous heavily-armored iron trains. Here we meet our main protagonist, Ikouma. Having sworn to get rid of the Kabane, he has created a weapon that can pierce through their solid heart. Sooner than later, he’ll find out how difficult it will be for his dream to come true.

Kabaneri of the Iron Fortress is a rollercoaster of a series. Our main protagonist suffers from having lost his family during the savage Kabane attack onto his village, which in turn, converted all of them into Kabane monsters themselves. This virus shows throughout many episodes how devastating it can be, and even though we don’t have an official number of victims, we can tell that humanity was in peril of extinction as it spread. Fueled with drama, revenge, political power struggles and lots of action, this is one series that everybody must watch at least once.

When the parasitic virus “Gastrea” made itself known among the population, it left the city in utter pandemonium, almost wiping out humanity in the city completely. Funny thing about humanity is that we’ve learned to adapt in order to survive the hardest of struggles and so we did with Gastrea. As monsters generated by the virus appeared, so did female children that were born from mothers infected by the virus. These “Cursed Children” would come to this world with abilities strong enough to defeat these monsters and with them, bring some balance and a fighting chance to society once again.

Rentarou Satomi, a survivor from Gastrea’s outbreak was able to witness the horrors of despair at a very young age. After ten long years he became a “Promoter” and partner of Enjou Aihara, one of many “Cursed Children” selected to be an “Initiator”. In other words, as soon as a monster appears, Enjou and Rentarou will arrive and fight until the monster is no more. While we don’t have a number of casualties, Gastrea is no simple virus. All it takes is a single wound infection and the host would start transforming into a monster that would go on attacking others. It may not be the fastest of viruses but it definitely is one of the deadliest, earning a spot in our list.

For the trio of Takashi Komuro, Rei Miyamoto and Hisashi Igou, high-school life couldn’t have been more stereotypical. Especially for Takashi, since it includes the classic love triangle drama. That would all change one day, however, as a strange man with undead features hurt high-school security and within a few seconds, that person died due to a flesh wound. Regardless, the man wouldn’t stay down for long and just like his predecessor, sharing his undead features would hurt and spread this virus quickly across the high-school. Now fighting for their lives, Takashi, Rei and Hisashi alongside other students, must find their way out, hoping to stay out of harm’s way before it’s too late and ultimately they become one of those undead creatures.

Coming straight out of a classic survival horror videogame-like story, Highschool of the Dead offers a set of likeable characters, lots of ecchi moments and angles and life or death situations thanks to one of the deadliest viruses to be set free in anime. Killing around 10.000 people in less than 24 hours, and spreading by infecting another being through open wounds, you can imagine how fast this virus could turn a city upside down and into a downright state/national quarantine! Definitely a series not only worth watching but also deserving of a spot in our list.

Yuichirou’s life had a rocky start, having parents that didn’t love him and being sent straight to an orphanage, you could imagine how chaotic his first years must have been. After arriving to the orphanage, though, he meets Mikaela. Another boy who welcomes him and helps him redefine what “family” really means. However, lurking from the shadows and unbeknownst to everyone around the world, other beings had plans that would affect the future of humanity. Unleashing a virus that killed every person under the age of thirteen, Vampires make their rise and enslave what’s left of humanity. As time goes by, both Yuichirou and Mikaela decide to escape their imprisonment; but as Vampires will show them, they might end up paying the ultimate price.

Owari no Seraph brings out in their story one of the most deadliest viruses there are in the world of anime and of course, on our list. By analyzing objectively, this virus released by the vampires is the cause of death of over 75% of the world’s population… in minutes. Without a doubt, this plan from hell was more than enough for them to overcome human society and establish themselves as the ruling beings on Earth. Definitely, one of the scariest viruses we hope never sees the light of day in our world.