Plague Inc. Swine Flu Scenario Mega-Brutal(3 Biohazard) Guide & Walkthrough

Spreading an influenza that caused mass panic throughout the world just a few years back, this is what the Swine Flu scenario is all about. In this scenario, you are given a chance to once again spread the infamous A(H1N1) virus. But as we all know, the world now has anti-virals that are effective against this virus, However(as stated in the scenario description) recent studies of the Swine Flu virus say that it has the potential to be as deadly as the 1918 'Spanish Flu' which has killed over 5% of the world's population--5% is not enough, we need to aim higher! 100% maybe?

Right at the beginning, you will be given a fixed set of transmissions and symptoms that you will have with to work with towards the eradication of the virtual human race.

Finishing the Swine Flu scenario with 3 Biohazards in mega-brutal difficulty will not be easy--Any scenario in mega-brutal difficulty is never easy. Before we move on to strategies for this scenario, I'll give you guys a little more background on this swine-started plague.

About Transmissions, Symptoms, and Abilities

Transmissions evolved at start
Right at the beginning of the game you will be given a fixed set of evolved transmissions and symptoms--similar to other scenarios such as Black Death, Smallpox, and Frozen Virus.

On the transmission side, you are started with Droplets 1 and Swine 1(reasonable enough because this IS the swine flu). Because of the Swine Flu's nature of being a virus, you are mostly given with transmissions that increase mutation.

Symptoms evolved at start
On the symptom side, 6 will be evolved right at the start. These symptoms are Pneumonia, Coughing, Sneezing, Pharyngitis, Fever, and Headache. You can choose to devolve these symptoms if you want to, I'd advise against it, though, since it costs DNA and it'll be much better to work with what you're given. As you may also notice, these symptoms are quite infectious and severe, so don't panic when your plague gets detected early.

Unlike transmissions and symptoms, there will be no pre-evolved abilities. Besides basic resistances for heat, cold, and drugs, you will also have the choice to evolve Viral Instability. This ability is also present in the basic plague, Virus. What this does is increase the chances of mutation and, in the swine flu scenario, you will be able to evolve this 3 times.

A Swine Flu unique ability will also be present, Bacterial Pneumonia. This ability boosts swine flu's severity and lethality by a fair amount--I think the amount of boost it provides increases as the game goes on, although I'm not quite sure about this.

If you thoroughly checked the available symptoms for evolution, you may notice that your plague's lethality at the late stages of the game might not be enough to kill fast, even with Bacterial Pneumonia ability evolved. Don't worry though, Swine Flu has another unique ability, Historic Reassortment.

Historic Reassortment and what it unlocks

Historic Reassortment
Historic Reassortment is a Swine Flu unique ability that can only be unlocked once you evolve the Bird 1 transmission. What this ability does is unlock more lethal symptoms to make the plague much more deadlier. 

You have to be really careful when you evolved this ability. Evolve it too early and you might mutate more lethal symptoms than infectious ones, evolve it too late and you won't be able to finish within a year--basic requirement for a 3 biohazards run, from what I can tell from experience.

Boxed are the unlocked symptoms
from Historic Reassortment
After evolving Historic Reassortment, a new symptom should appear at the bottom left corner of the symptoms tab. This symptom is Epistaxis, and it stems into five more lethal symptoms which are: Haemoptysis, Pulmonary Haemorrhage, Haemorrhagic Shock, Cytokine Storm, and finally Total Organ Failure. These symptoms combined with the already available symptoms will max out the lethality enough to kill people within a few months. Speaking from experience, having these symptoms before maxing out every transmission is not a good idea. Without Necrosis, you will kill faster than infecting people.

What it takes to get a 3 Biohazard score

In my experience of playing a lot of Plague Inc. games in mega-brutal difficulty, the basic stats that I think you should have at the end of the game should be: 65,000 score or more, 370 days or less, with a cure completion of below 65%.

Because I'm not so sure about the stats you should have, here's some screenshots of my recent Swine Flu games that finished with a 3 biohazard score.

On average, you have to finish within 345 days with a 50% cure completion(This average is purely based upon the scores posted above.).

Things to remember:

Here are some tips and things to remember while using the strategies and guides posted here.
  1. Every Plague Inc. game is different. Country infection order, events, and bubble appearances are all different in every game.
  2. You don't have to follow the guide down to the last evolution. Always be prepared to change things up if you feel it's necessary.
  3. Mutations are random. The mutation order can be beneficial at times but it can also destroy your game. 
  4. If you have any tips you'd like to share, post them at the comments below. We'll include helpful ones along with this guide.

Spicy's Strategy

Current success rate and what affects it

On the last 5 games I've had using this strategy, I've won 3 times. The 2 losses I had were both because of the late infection of one island country--In the first loss, it was the Caribbean. In the second, it was New Zealand.

These are the things, which I believe, affects the success of this strategy
  • Random mutations. These heavily affect this strategy's success. Swine Flu is considered to be a Virus(see Disease type at stats page) so mutations are always bound to happen. Most transmissions are also of the animal type which further boosts the chances of mutations.
  • Events such as "being placed on the WHO watch list" and "Threat level increase by WHO" will significantly increase the cure progression and also prompt countries to close their borders and point of entries(harbors and airports) earlier than usual.
  • Late infection of Rich and Island countries. Rich countries take quite a considerable time to infect so you want them to be infected as soon as possible. And as always, Island countries that can only be accessed through a harbor are always a problem. 
  • Additional tips will be added as soon as people comment on the strategy.

Gene Setup:

Feel free to change this up if you want.
  • ATP Boost - This has always been my go-to gene on every mega-brutal game, 8 DNA at the very beginning is always helpful
  • Aquacyte - Island countries are hard to infect since some of them can only be accessed by ship. 
  • Trans-Stasis - We'll be evolving more transmissions than symptoms and abilities, so it's only necessary to have this to prevent the increase of DNA costs
  • Darwinist - Genetic Mimic is also an option but I'd rather take my chances on mutations with this strategy. Due to the nature of Swine Flu of being a Virus, symptoms will mutate either way.
  • Hydrophile - This is to boost the infection rate in our starting country. The infection bonus is also carried to other humid countries.

The Strategy:

1.) Before selecting a country to start in, evolve the following:
  • Droplets 2
  • Nausea - I chose to evolve this just in case the event "festival of love" shows up.
  • Rash
2.) Start in India
3.) Evolve the following in this order:
  • Swine 2
  • Livestock 1
  • Water 1
  • Air 1
  • Water 2
  • Livestock 2
  • Air 2
  • Extreme Bioaerosol
  • Blood 1
  • Blood 2
  • Cold Resistance 1
  • Drug Resistance 1
  • Cold Resistance 2
  • Drug Resistance 2
  • Bird 1 - This unlocks the Historic Reassortment ability
  • Bird 2
  • Extreme Zoonosis
  • Historic Reassortment
  • Genetic Hardening 1
  • Genetic Hardening 2 - I always skip this when its DNA cost increases to 40 or more. There are also some games where I just skipped this.
4.) At this point, most countries should already be infected. Continue by evolving the following symptoms if they have yet to mutate(best to follow the order):

  • Vomiting
  • Hyper Sensitivity
  • Diarrhoea
  • Inflammation - This along with the 3 symptoms above are evolved to increase infection
  • Insomnia
  • Paranoia
  • Fatigue - This along with the 2 symptoms above are evolved to further slow the cure
  • Epistaxis
  • Haemoptysis
  • Pulmonary Haemorrhage - This along with the 2 symptoms above are evolved so that mutations will evolve much more lethal symptoms.
5.) At this point in the game, all countries should now be infected. Spend DNA on evolving all three Genetic Re-Shuffles. After all three Re-Shuffles are evolved, remaining DNA is best put towards evolving lethal symptoms--You could also choose to evolve lethal symptoms earlier if the whole world is already infected. Remember to keep the cure completion below 60% to ensure a 3 biohazard score. 

The evolutions at this part of the game is usually based on your decision. Do you need more lethality? Or do you need to stall the cure? A piece of advice, only evolve lethal symptoms when the whole world is completely infected.

Here's what my Plague's abilities, transmissions, and symptoms looked like when I got the "humans to be eradicated" pop-up.

That about does it. I hope this guide has helped you get those 3 sweet golden biohazards at the end of the game. Remember to post helpful tips and strategies you may have to further improve this guide. HSG!


  1. Great, Didnt work for the 3 biohazards but still finished it on mega brutal 2 biohazards.

  2. Worked great for three bio-hazards! I also used the secondary infection ability towards the end to wipe them out that much faster.

  3. Sheer bad luck in that, despite its boat port staying open to the end, no one - NO ONE - took a damn boat to Greenland.

  4. I actually cheered quite loudly when all the islands were infected. Got there in the end :)

  5. I got 3/3 biohazards with Spicy's strategy. It works so well

  6. Chelsea EnergizerBunny BlairAugust 22, 2014 at 2:59 PM

    Carribean closed its port. ugh

  7. Canada was left with half population infected with Canada only left and it dried becaus total organ failure mutated 3 times after devolving it lost SO CLOSE!

  8. This strategy doesn't work any more. Are you going to update it?

  9. You have to hope that Canada gets infected early, or else the infection rate won't be high enough in the end. If you get to USA early, you might want to evolve the Bird transmissions earlier to get into Canada through land.

  10. I read as far as gene set up and have it a go. First attempt I got over 71k score and 3 platinum bio symbols (first time ordering that) so now all my gold bio symbols mean nothing to me...-,-

  11. * First time seeing that