How the Infection Started in The Last of Us – Unraveling the Origins of the Pandemic

The infection that ravages the world in the game “The Last of Us” is a terrifying and deadly force that completely changes the course of humanity. It is a start of despair, fear, and the fight for survival. What exactly is this infection and how did it come to be? In this article, we will explore the origins of the infection in “The Last of Us” and how it spreads.

The infection in “The Last of Us” is caused by a mutated strain of the Cordyceps fungus, a real-world fungus that typically affects insects. However, in the world of the game, this fungus has somehow adapted to infect humans and turn them into mindless, aggressive creatures. This adaptation is believed to have occurred through a combination of natural evolution and genetic engineering gone wrong.

At the start of the game, it is revealed that the infection first spread in the United States, leading to the collapse of society and the rise of infected creatures known as the “infected.” The exact source of the initial outbreak is never fully explained, but it is suggested that it may have originated from a combination of factors, including contaminated food or water supplies, as well as the accidental release of the fungus in laboratory experiments.

The infection spreads through direct contact with the infected or their bodily fluids, making it highly contagious and difficult to contain. Once a person becomes infected, the fungus slowly takes over their body, transforming them into a terrifying and dangerous creature. The infection progresses at different rates depending on the individual, with some succumbing to the fungus’s control within days, while others may take weeks or even months before fully transforming.

Overall, the origin of the infection in “The Last of Us” is a chilling reminder of the unpredictable nature of biological threats and the catastrophic consequences they can have on society. As players navigate the post-apocalyptic world of the game, they are confronted with the grim reality of a world devastated by infection, a constant reminder of the frailty of human existence and the desperate fight for survival.

Outbreak of Cordyceps Fungus

The start of the infection in The Last of Us centers around the outbreak of the Cordyceps fungus, a parasitic fungus that primarily affects insects. However, in this post-apocalyptic world, this fungus has evolved to infect humans and has devastating consequences.

The infection begins when spores from the Cordyceps fungus are inhaled or come into contact with an open wound. Once inside the body, the fungus quickly takes over the host’s brain, turning them into aggressive and mindless creatures known as infected.

Effects on the Infected

  • The infected become highly aggressive and attack any non-infected individuals they come across.
  • They lose all sense of their former selves and are driven solely by the desire to spread the infection.
  • Their appearance changes drastically, with fungal growths protruding from their bodies.
  • Their movements become erratic and unpredictable, making them formidable and difficult to kill.

Transmission and Spread

The infection can spread through various means:

  1. Direct contact with an infected individual, either through bites or close proximity.
  2. Inhalation of airborne spores released by infected individuals or fungal growths.
  3. Transmission through bodily fluids, such as blood or saliva.

Due to the highly contagious nature of the infection, it spreads rapidly through communities, resulting in the collapse of civilization as we know it.

In conclusion, the outbreak of the Cordyceps fungus in The Last of Us serves as the catalyst for the apocalyptic events depicted in the game. The infection is terrifying and relentless, posing a constant threat to the survival of the protagonists and creating a tense and dangerous environment.

Infectious Spores Spread

The infection in The Last of Us starts with the spread of infectious spores. These spores are released by the Cordyceps fungus, a parasitic fungus that primarily infects insects in the real world. However, in The Last of Us, the fungus has mutated and can infect humans as well.

The spores are highly contagious and can be transmitted through the air. When someone inhales the spores, they can become infected. The spores then start to grow inside the host’s body, eventually taking control of their brain and turning them into a mindless, aggressive creature known as an Infected.

It is believed that the infection initially spread through contact with infected animals or by breathing in spores that were released into the air. As the infection progressed, it became easier for humans to get infected, leading to the collapse of civilization.

The spores are highly resilient and can survive in different environments, making them difficult to eliminate. They can be found in areas with high humidity, such as underground tunnels and abandoned buildings. The spores can also be carried by infected creatures, further contributing to their spread.

Once infected, there is no known cure for the infection. The only way to prevent further spread is to avoid contact with infected individuals and areas heavily contaminated with spores. Survivors in The Last of Us have to constantly be on guard and take precautionary measures to avoid getting infected.

In conclusion, the infectious spores in The Last of Us play a crucial role in the start and spread of the infection. They are highly contagious, resilient, and can infect both humans and animals. Understanding how the spores spread is essential for survival in the post-apocalyptic world of The Last of Us.

Initial Symptoms of Infection

In The Last of Us, the infection that plagues humanity is caused by a mutant strain of fungus known as Cordyceps. This fungus is airborne and attacks the human body, taking control of its host and transforming it into a mindless creature driven by its basic instincts.

When a person first becomes infected, they may experience a series of initial symptoms. These symptoms can vary from person to person, but there are several common signs to look out for.

1. Flu-like symptoms

One of the initial symptoms of infection is flu-like symptoms. This can include fever, chills, body aches, and fatigue. These symptoms can initially be mistaken for a regular seasonal flu, but they often persist and worsen over time.

2. Respiratory issues

As the infection progresses, the fungal spores take root in the respiratory system, leading to breathing difficulties. Infected individuals may develop a persistent cough, wheezing, and shortness of breath. These respiratory issues can become increasingly severe as the infection spreads.

It’s important to note that these initial symptoms may appear similar to other common illnesses, making it challenging to identify the infection at an early stage. However, as the infection progresses, it becomes evident that something far more sinister is at play.

In conclusion, the initial symptoms of infection in The Last of Us may include flu-like symptoms and respiratory issues. These signs serve as a harbinger of the devastating transformation that awaits those infected by the mutant strain of Cordyceps in this post-apocalyptic world.

Global Panic

The outbreak of infection in The Last of Us created mass panic worldwide. As the infection rapidly spread, governments and nations struggled to contain it. The origins of the infection are still not fully understood, but it is believed to have originated from a mutated fungus that affects the brain. This fungus, known as Cordyceps, is found in nature and typically infects insects. However, in The Last of Us, it has jumped species and can infect humans.

The global panic started as reports of a mysterious illness emerged, with individuals showing aggressive behavior and a rapid deterioration of their physical and mental state. As the infection spread, it became clear that it was highly contagious, easily transmitted through bodily fluids and close contact with infected individuals.

Infected individuals, known as “the infected” or “the clickers” due to the distinct clicking sound they make, would exhibit violent behavior and a hunger for human flesh. This, combined with the rapid speed at which the infection spread, caused widespread panic and chaos.

Humanity began to collapse under the weight of the infection. Governments and military forces struggled to maintain control and protect their citizens. Quarantine zones were established, but they proved to be ineffective in the long run. As the infection continued to spread, society crumbled, leaving survivors to fend for themselves in a world overrun by infected and desperate humans.

Ultimately, the global panic portrayed in The Last of Us demonstrates the devastating consequences of an uncontrollable and rapidly spreading infection. It serves as a reminder of the fragility of civilization and the lengths people will go to survive in a world where the infected are no longer human.

Government Struggle to Control

In the face of the last outbreak of infection, the government was faced with the daunting task of trying to control the rapidly spreading virus. The start of the infection caught authorities off guard, and they were ill-prepared to handle the crisis.

The government’s first response was to establish quarantine zones in major cities, hoping to isolate the infected and prevent the spread of the virus. However, these measures proved to be ineffective as the infection continued to spread outside of these zones.

Desperate to find a solution, the government implemented stricter regulations, including strict curfews and travel restrictions. They also allocated significant resources to research and development, hoping to find a vaccine or cure for the infection.

Despite their efforts, the government struggled to gain control over the infection, as the virus continued to mutate and adapt. This made it difficult for scientists to develop an effective treatment or preventive measure.

In the end, the government’s struggle to control the infection led to the collapse of society as we know it. The world descended into chaos, with survivors fighting for their lives in a post-apocalyptic wasteland.

Looking back, it’s clear that the government’s response was too little, too late. The last outbreak of infection was a stark reminder of the importance of early detection and response in the face of a global pandemic.

Quarantine Zones Established

As the infection started spreading rapidly, the authorities in the United States realized the need for immediate action to contain the outbreak. To prevent further spread of the infection, quarantine zones were established throughout the country. These zones were designated areas where the infected individuals were isolated and monitored, with strict restrictions placed on travel in and out of the zones.

In an attempt to maintain order and protect the uninfected population, the government set up military checkpoints at the entrances and exits of the quarantine zones. These checkpoints were heavily guarded to ensure that only authorized personnel were allowed to pass. Anyone showing signs of infection or attempting to leave the zone without proper clearance was apprehended and taken into custody.

Inside the quarantine zones, daily life became tightly controlled. Supplies were rationed, and strict curfews were implemented to minimize contact between individuals. Residents were required to clean and disinfect their living areas regularly to prevent the spread of the infection. Any symptoms of the infection were to be reported immediately to the designated medical staff.

Although the establishment of quarantine zones was a necessary measure to contain the infection, it also came with its challenges. The crowded living conditions and limited resources within the zones often led to tensions and conflicts among the residents. Additionally, the isolation within the zones meant that the authorities could not effectively control the black market trade and illegal activities that thrived underground.

Despite these challenges, the quarantine zones initially proved to be an effective way to slow down the spread of the infection. However, as the infection continued to evolve and new threats emerged, it became clear that the quarantine zones alone were not enough to contain the outbreak. The story of The Last of Us explores the aftermath of the infection and the struggles of the remaining survivors in a world where the concept of a safe quarantine zone is no longer viable.

Surge in Infected Numbers

The start of the infection in The Last of Us marked the beginning of a devastating global pandemic. The infection rapidly spread, causing a surge in infected numbers.

The infection, caused by the Cordyceps fungus, primarily affects humans. The Cordyceps fungus infects the brain, taking control of its host’s body and transforming them into aggressive and highly dangerous creatures known as the infected.

As the infection spreads, more and more individuals fall victim to its devastating effects. The infected exhibit various stages of the infection, ranging from early symptoms to full transformation. This surge in infected numbers puts survivors at an increased risk of encountering hostile creatures, making survival even more challenging.

The surge in infected numbers also led to the collapse of society as we know it. Governments were unable to contain the spread of the infection, resulting in widespread panic, chaos, and mass hysteria. The survivors are left to navigate a world overrun by infected and desperate humans, where every decision could mean the difference between life and death.

In The Last of Us, the surge in infected numbers serves as a constant reminder of the danger and despair that permeates the post-apocalyptic world. This overwhelming presence of infected creates an atmosphere of fear and tension, as survivors must constantly be on guard and make difficult choices to stay alive.

Transformation into Infected

The transformation into an infected individual in The Last of Us starts with the initial stages of infection. When a person is bitten or comes into contact with an infected individual, the infection begins to spread throughout their body. The infection gradually takes over the host, causing physical and mental changes.

The infection in The Last of Us is caused by a mutative strain of the cordyceps fungus. This fungus targets the brain, taking control of the host’s motor functions. As the infection progresses, the host’s body undergoes a series of changes.

  • Stage 1: The initial stage of infection is characterized by flu-like symptoms, including fatigue, fever, and body aches. The infected individual may experience headaches and coughing. This stage can last for several days.
  • Stage 2: In stage 2, the infection begins to affect the host’s behaviour. The infected individual becomes more aggressive and starts showing signs of decreased rationality. They may exhibit increased aggression and hostility towards others.
  • Stage 3: Stage 3 is the final stage of infection. At this point, the infected individual has completely transformed into a ferocious infected creature. Their body undergoes severe physical changes, including the growth of fungal growths, particularly around the face and head. The infected individual loses all sense of humanity and becomes a relentless predator.

The transformation into an infected in The Last of Us is a gradual process that ultimately results in the loss of humanity. The infected individuals become dangerous threats, spreading the infection further and posing a constant danger to uninfected survivors.

Different Stages of Infection

In The Last of Us, the infection begins with what is commonly referred to as “the start”. At this stage, a person becomes infected with the Cordyceps fungus, and it begins to replicate within their body. The infected individual may experience flu-like symptoms, such as fever, coughing, and weakness. However, these initial symptoms can be easily mistaken for a common illness.

As the infection progresses, it enters its second stage in which the fungus starts to take control of the host’s brain. At this point, the infected individual becomes highly aggressive and loses their cognitive functions. They are driven only by their urge to find a non-infected host and spread the infection further. Physical mutations become apparent, such as the growth of fungal structures on the face and body.

The third and final stage of infection in The Last of Us is known as the “clicker” stage. At this point, the Cordyceps fungus has completely taken over the host’s brain, transforming them into a highly dangerous and deadly creature. The infected individual loses their sight completely, but their hearing becomes highly sensitive. They navigate their surroundings through echolocation, emitting clicking noises to detect any potential threats.

Stage Symptoms Physical Changes
The Start Flu-like symptoms N/A
The Second Stage Aggression, loss of cognitive functions Growth of fungal structures
The Clicker Stage Loss of sight, enhanced hearing Grossly mutated appearance

In conclusion, The Last of Us portrays different stages of infection caused by the Cordyceps fungus. From the start with flu-like symptoms to the aggressive second stage and the deadly clicker stage, the infection’s progression is a pivotal aspect of the game’s narrative and gameplay mechanics.

Modes of Transmission

The infection in The Last of Us is primarily transmitted through direct contact with the infected individuals or their bodily fluids. The two main modes of transmission are:

1. Direct Contact Direct contact with infected individuals can occur through physical contact, such as touching, kissing, or sexual intercourse. This mode of transmission is particularly dangerous as it allows the infection to easily spread from one person to another.
2. Bodily Fluids Another mode of transmission is through exposure to infected bodily fluids, such as blood, saliva, and mucus. This can occur when there is contact with open wounds, mucous membranes, or through the sharing of contaminated objects.

It is important to note that the infection can also be transmitted through indirect contact with contaminated surfaces, although the risk of transmission is significantly lower compared to direct contact or exposure to bodily fluids.

The Last of Us portrays an incredibly realistic depiction of the spread of infection and the devastating consequences it has on humanity. By exploring the different modes of transmission, the game highlights the importance of caution and vigilance in a world plagued by a deadly outbreak.

Resistance and Immunity

In the world of The Last of Us, the start of the infection led to a catastrophic collapse of society. However, not everyone was affected equally by the Cordyceps fungus. Some individuals showed resistance to the infection, while others developed immunity.


Resistance to the Cordyceps infection is observed in certain individuals who can come into contact with the fungus without succumbing to its effects. These resistant individuals are generally able to withstand exposure to spores and avoid the transformation into infected creatures.

Resistance may be the result of genetic factors or prior exposure to the fungus, which allows the immune system to develop a defense mechanism against the infection. It is also possible that certain external environmental factors play a role in enhancing resistance.


Immunity, on the other hand, refers to the complete inability of an individual to be infected by the Cordyceps fungus. Immune individuals have an exceptionally strong immune system that can entirely repel the fungus and any attempts of infection.

While resistance provides some level of protection against the infection, immunity is a much rarer occurrence. Immune individuals are extremely rare in the world of The Last of Us, and they are often sought after by various factions and organizations.

Understanding the mechanisms behind resistance and immunity in The Last of Us is crucial for understanding the dynamics of the post-apocalyptic world. It sheds light on the factors that determine who succumbs to the infection and who manages to survive, and it plays a significant role in shaping the narrative of the game.

Human Response to the Outbreak

The outbreak in The Last of Us marked the beginning of a devastating chain of events, testing the limits of humanity’s ability to cope with an infection unlike anything seen before. As the infection spread rapidly, the world plunged into chaos, forcing individuals and governments to quickly adapt and respond to the crisis.

At the start of the outbreak, there was a general lack of understanding about the infection and how it spread. Panic and fear gripped society, leading to widespread panic-buying, looting, and social unrest. Governments struggled to contain the situation, implementing strict quarantine measures and establishing military-controlled zones to maintain order.

As the infection continued to spread and the true nature of the outbreak became clearer, efforts were made to develop a vaccine. Numerous research facilities and organizations around the world dedicated themselves to finding a cure and preventing the further spread of the infection. However, progress was slow, and the hope of a quick solution began to wane.

Human Response to the Outbreak
Initial panic and fear Widespread panic-buying, looting, and social unrest
Government response Implementing strict quarantine measures and military-controlled zones
Efforts to develop a vaccine Multiple research facilities and organizations dedicated to finding a cure

Survival quickly became the primary focus for many individuals, as law and order broke down in many regions. Communities formed, where people banded together for protection and support. However, not all settlements were successful, and conflicts emerged over limited resources.

With the absence of a widely available cure, society had to learn to adapt to the new reality. The infected posed a constant threat, and individuals had to be vigilant to avoid becoming one of them. The survivors quickly realized that traditional rules and norms no longer applied in this new world.

Overall, the human response to the outbreak in The Last of Us showcased the extremes of human nature. While some individuals displayed selflessness, compassion, and resilience, others succumbed to fear, violence, and despair. The struggle to survive and find hope in a world devastated by infection became the defining characteristic of humanity’s response to the outbreak.

Role of Military and Civilian Groups

The start of the infection in The Last of Us was a highly complex and devastating event that brought chaos and destruction to the world. Both military and civilian groups played significant roles in the outbreak and subsequent spread of the infection.

Military Groups

The military initially had a critical role in containing the infected and maintaining order. They were tasked with protecting civilians and establishing quarantine zones. Their presence was crucial in the early stages of the outbreak, as they were able to utilize their resources and expertise to combat the infected and maintain a semblance of control. However, as the infection continued to spread and resources became scarce, the military’s ability to effectively control the situation started to wane.

As the infection progressed, some military groups became more authoritarian and ruthless. They implemented strict rules and regulations, often resorting to violence to maintain order. This led to strained relationships with civilians and fueled resentment and distrust. Some military factions even resorted to conducting experiments on the infected, further exacerbating the situation and causing the infection to spread even more rapidly.

Civilian Groups

In contrast to the military, civilian groups emerged as pockets of resistance and a glimmer of hope amidst the chaos. People banded together in small communities, pooling their resources and skills to survive. These groups highlighted the power of human resilience and the importance of unity in the face of adversity.

Civilian groups often had to fend off both infected and military threats, facing constant danger and instability. They utilized a range of survival skills, such as scavenging for supplies, establishing makeshift defenses, and developing strategies for dealing with the infected. However, tensions and internal conflicts within these groups were also common, as the pressures of survival strained relationships and tested individuals’ morality.


The military and civilian groups were both integral to the origin and spread of the infection in The Last of Us. While the military initially served as a symbol of authority and protection, their increasing brutality and desperation ultimately contributed to the chaos. Civilian groups, on the other hand, represented the resilience and adaptability of humanity in the face of overwhelming odds. The roles and actions of these groups shaped the post-apocalyptic world portrayed in the game, creating a complex and immersive narrative experience.

Survival in Post-Apocalyptic World

In the post-apocalyptic world of The Last of Us, survival becomes the primary concern for the individuals navigating through the infected world. The infection that plagues us is not only deadly but also highly contagious, making every encounter with infected individuals a potential life-or-death situation.

To survive in this world, one must be equipped with the necessary skills and knowledge. The ability to scavenge for resources, such as food, water, and weapons, is crucial for sustaining oneself in the long run. Without these essential items, survival becomes nearly impossible in the harsh and unforgiving environment.

Adaptability is another vital aspect of surviving in the post-apocalyptic world. The infected in The Last of Us are not mindless zombies; they retain some level of intelligence and can strategize to hunt down their prey. Therefore, one must be constantly alert and ready to adapt to the ever-changing circumstances and threats that arise.

Forming alliances and building relationships with fellow survivors is also crucial for survival. As Joel and Ellie demonstrated throughout their journey, having someone to watch your back and provide support can make all the difference in the fight against the infected and other hostile factions. Trust and cooperation become essential elements for survival in this new world.

Furthermore, maintaining one’s mental and emotional well-being is vital in a world where despair and loss are commonplace. Coping with trauma and grief, finding moments of joy and hope, and holding onto humanity can provide the necessary motivation to keep fighting, even when all seems lost.

In conclusion, survival in the post-apocalyptic world of The Last of Us is a constant battle against the infected and the harsh environment. Scavenging for resources, adapting to the threats, forming alliances, and maintaining mental well-being are critical aspects of successfully navigating this dangerous world. Only those who are resilient, resourceful, and determined can hope to survive the brutal reality of The Last of Us.

Ethical Dilemmas and Moral Choices

Throughout the game, The Last of Us explores a number of ethical dilemmas and moral choices that the characters are forced to confront in their struggle for survival in a world ravaged by infection. The start of the infection leads to a breakdown of societal norms and raises important questions about what it means to be human.

One of the main ethical dilemmas in the game is the decision to save or sacrifice others in order to ensure one’s own survival. As the infection spreads and resources become scarce, characters are faced with the difficult choice of choosing between their own well-being and the well-being of others. This moral choice is particularly prominent in the relationship between Joel and Ellie, as they navigate a harsh and unforgiving world together.

Another ethical dilemma explored in the game is the use of violence as a means of survival. The Last of Us presents a world where violence is often necessary for self-defense and protection. However, it also raises questions about the morality of killing others, even if it is in self-defense. The game forces players to confront their own moral compass and consider the impact of their actions on others.

The last of Us also delves into the ethics of scientific research and experimentation in the pursuit of finding a cure for the infection. In the game, characters are faced with the choice of using potentially harmful methods and sacrificing individuals for the greater good. This raises important questions about the value of individual lives and the lengths to which humans are willing to go in the face of a global crisis.

Overall, The Last of Us presents players with thought-provoking ethical dilemmas and moral choices that force them to examine their own values and beliefs. The game encourages players to consider the consequences of their actions and the impact they have on others in a world consumed by infection.

Hope for a Cure in The Last of Us

Throughout the game, The Last of Us, the start of the infection is depicted as a bleak and devastating event. However, amidst the despair and chaos, there is a glimmer of hope for a cure.

The infection that ravaged the world in The Last of Us has left most of humanity infected or dead. The origins of this infection are mysterious, but what is clear is that it spreads through bites or contact with infected bodily fluids.

Despite the grim situation, there are characters in the game who believe that a cure is possible. The protagonist, Joel, is tasked with escorting Ellie, a young girl who is immune to the infection, to a group of scientists who may be able to develop a cure using her unique biology.

This journey becomes a symbol of hope for both the characters and the players. The possibility of finding a cure offers a glimmer of hope in an otherwise bleak and desolate world.

Throughout their journey, Joel and Ellie face numerous obstacles and dangers, but they persevere, driven by the hope that their efforts will lead to a cure. Their determination and resilience inspire players to believe in the possibility of a better future.

While the game ultimately leaves the fate of humanity uncertain, it reminds us of the importance of hope in the face of adversity. The Last of Us reminds us that even in the darkest of times, there is always a chance for redemption and a brighter tomorrow.

Question and answer:

What is the origin of the infection in The Last of Us?

The origin of the infection in The Last of Us is a mutated strain of the Cordyceps fungus.

How does the infection spread in The Last of Us?

The infection in The Last of Us spreads through the air, as well as through direct contact with infected individuals or their bodily fluids.

When did the infection start in The Last of Us?

The infection in The Last of Us started in September 2013, when the Cordyceps fungus mutated and began infecting humans.

Are there any real-world equivalents to the Cordyceps fungus in The Last of Us?

Yes, the Cordyceps fungus in The Last of Us is based on a real-world fungus that infects insects and other arthropods.

What are the symptoms of infection in The Last of Us?

The infected in The Last of Us exhibit symptoms such as aggressive behavior, fungal growth on the body, and a loss of higher brain function.

What is the origin of the infection in The Last of Us?

The infection in The Last of Us is caused by a mutated strain of the Cordyceps fungus, which typically infects and takes over the brains of ants and other insects.

How does the infection spread in The Last of Us?

The infection in The Last of Us spreads through inhalation of fungal spores or through direct contact with infected fungal matter. Once the spores enter the body, they begin to grow and take over the host’s cells, eventually transforming them into “infected” creatures.

Is The Last of Us based on a real-life infection?

The Last of Us is not based on a specific real-life infection, but it takes inspiration from the Cordyceps fungus, which does have real-life counterparts that infect insects. The game’s depiction of the infection is fictional and exaggerated for dramatic effect.

Can humans be infected by the Cordyceps fungus in real life?

While the Cordyceps fungus primarily infects insects, there have been rare cases of humans being infected. However, these infections are typically localized and do not result in the same level of transformation seen in The Last of Us. It’s important to note that the game’s depiction of the infection is highly fictionalized.

Are there any similarities between the infection in The Last of Us and real-life diseases?

There are some similarities between the infection in The Last of Us and real-life infectious diseases. Both involve the spread of a pathogen and the transformation of infected individuals. However, the Cordyceps infection depicted in the game is a fictionalized and exaggerated version of real-life infections.