Plague Inc. Wiki

The following are strategies for the Bio-Weapon Plague Type. Please feel free to add your own strategies, tips, and Q&A here: If you aren't quick enough to devolve a mutation before it's spotted, then pause the game time, then devolve the mutation.
If you want to write new strategies, please use this page.

Strategy 1

Note: This strategy does not seem to work on mega-brutal difficulty. Due to high cost of DNA, you will be unable to evolve the trait "Unlock Annihilate Gene" since you will be lacking DNA points. You can overcome this by either using Patho-Stasis to prevent the ability cost from going up, or use Ionised Helix and de-volve the transmission traits when there is "No healthy people left in the world" to have enough DNA to purchase "Unlock Annihilate Gene". This guide may also not work on Brutal. Disease always struggles to infect Greenland fast enough to infect whole world. Not enough DNA to slow down cure research.

  1. Start in India.
  2. Buy Gene Compression 1 and 2.
  3. Buy Air 1 and Water 1.
  4. Buy Coughing. Don't worry about this. It isn't enough for scientists to notice.
  5. Buy Gene Compression 3.
  6. Buy Deactivate modified genes 1. With Gene Compressions 1-3, this will be very effective and Lethality will come up relatively slow.
  7. Evolve the following (better in order) : Water 2, Air 2, Cold Resistance 1, Extreme Bioaerosol, Cold Resistance 2, and Drug Resistance 1 and 2.
  8. During step 7, if your plague starts killing again, get Deactivate modified genes 2.
  9. Also, until more than 5 countries starts work on the cure, devolve any symptoms that are not Coughing (you're lucky if this evolve the first, you will save some DNA points), Rash, Cysts, Sneezing or Sweating.
  10. Stock up on DNA points now. If your plague starts killing, evolve Nucleic Acid Neutralisation 1, wait until it kills a few more people (100,000), and then evolve Nucleic Acid Neutralisation 2, and after it kills again, evolve Deactivate modified genes 3.
  11. By now your DNA bar should fills up quickly, if your plague starts to kill a lot again, gets Nucleic Acid Neutralisation 3.
  12. When there are no healthy people left in the world, get Unlock Annihilate gene. The cure shouldn't be over 50% by now.
  13. Sit back and win. If you are cautious and want to make your victory 100%. Slow the cure with Insomnia, Paranoia, Seizures, Insanity, Paralysis and Coma. If you are not done, evolve Genetic ReShuffle 1.
  • That's all done, this plague's final stage is pretty easy, but the start and the middle is the difficult part.

Strategy 2

Recommended Genetic Code:

  • ATP Boost: Gene Compression is essential at the very beginning of the game.
  • Genetic Mimic: The cure progresses at a slower rate.
  • Aquacyte: Island countries are not a big problem with this gene evolved.
  • Extremophile: A good bonus in all environments is always nice to have.
  • Patho-stasis: The use of special abilities is essential for Bio-Weapon. Keeping DNA costs to a minimum is generally useful.
  1. Start in a country with a hot climate (i.e. India).
  2. Evolve Gene Compression 1, 2 and 3 as soon as possible.
  3. Evolve in order: Water 1, Air 1, Water 2, Air 2, Cold Resistance 1, Drug Resistance 1, Extreme Bioaerosol and Drug Resistance 2.
  4. If a plague's lethality is too high or the plague unexpectedly mutates a lethal symptom, evolve Deactivate modified genes 1 (Reduces lethality) and Nucleic Acid Neutralisation 1 (Lethality does not increase for a short time).
  5. Evolve Cold Resistance 2 to ensure infectivity in cold countries, especially Greenland.
  6. Keep the plague under control by evolving Deactivate modified genes 2 and Nucleic Acid Neutralisation 2.
  7. When every country is infected, evolve Coughing to increase infectivity.
  8. When the "There are no healthy people in the world" popup appears, evolve Deactivate modified genes 3 and Nucleic Acid Neutralisation 3 if they had not been evolved before. Then, evolve Unlock Annihilate gene, and after that evolve Genetic Hardening 1 and 2, Insomnia, Paranoia, Seizures, Insanity and Coma (if you have the DNA for it).

Watch the plague destroy the world.

Strategy 3 (Mega Brutal)

This strategy works on Mega Brutal and it's not even that complicated. For genes, I think you could use any but here are my recommendations :

  • Catalytic Switch (Useful for DNA resources on late game)
  • Aquacyte (Needed to infect islands and the most annoying one; Greenland)
  • Patho-Stasis (Needed for the final kill)
  • Genetic Mimic (Absolutely required, in Mega Brutal, they will be curing the plague really fast)
  • Extremophile (Or literally anything)

Alright so for the strats, we gonna focus on infecting since Bio Weapon kills very fast, I won using this strategy after 2 times so I guess it's 50-50 to win (I lost because of Greenland)

  1. Start in Saudi Arabia
  2. Evolve Rash, Sweating, and Skin Lesions Note : Don't always devolve the symptoms except if it's too lethal like Necrosis
  3. Evolve Gene Compression 1,2,3
  4. Evolve Air 1, Air 2, Water 1, Water 2, and Extreme Bioaerosol
  5. Evolve Deactivate Modified Genes and Nucleic Acid Neutralisation (we'll need this for the final kill anyway so feel free to max them out)
  6. Evolve Cold Resistance 1,2 Drug Resistance 1,2 and Genetic Hardening 1,2
  7. Wait until the whole world infected, if it's not fast enough, evolve Coughing and Sneezing. Bird 1, 2 is optional
  8. If Greenland closes ports before you infect it, restart
  9. Evolve Genetic Reshuffles as needed (if the cure > 75%)
  10. If the whole world have been infected, evolve Unlock Annihilate Gene
  11. Watch the world dies and congratulations, you've won.


Strategy 4 (Mega-Brutal)

This strategy is extremely aggressive and requires some genes to work. The gene's purpose is listed with where they are


Atp Boost (Required for early symptoms)

Genetic Mimic (To counter Sympto-Stasis)

Aerocyte (Early bubbles)

Extremophile (It helps a lot with spreaded across all countries)

Sympto-Stasis (You will be buying a lot of symptoms)

  1. Start in Saudi Arabia
  2. Pop the red bubble immediately to evolve the following: Insomnia, Cysts, Rash, Nausea
  3. Evolve the following until you have infected a few countries: Sweating, Vomiting, Paranoia, Hyper sensitivity, Skin Lesions, Air 1, Water 1, Bird 1, Air 2, Water 2, Bird 2, Extreme Bio-aerosol, Diarrhea, Pulmonary Oedema, Pulmonary Fibrosis, Pneumonia, Coughing, and Sneezing
  4. Once you have infected several countries, you should be swimming in DNA points, Evolve Drug resistance 1, and Cold resistance 1 & 2.
  5. Evolve all traits missing from the top.
  6. Wait and if the cure is a problem evolve Genetic Hardening if it is early, and Genetic Reshuffle if it has already progressed a bit. The high infectivity that your symptoms gave will make you spread across the world at an alarming rate, and the severity of them will provide enough DNA to win.
  7. By the time the cure is about 30%, take or give a bit, you should have at least 1 infected in the entire world
  8. With the DNA points you saved up, evolve Necrosis and Hemorrhagic shock, with necrosis coming first. If possible, also evolve total organ failure. If there is still a lot of DNA points, you can either buy cure delaying symptoms like coma and insanity or buy more lethal genes to win faster.

This strategy works very well and extremely fast, in my 5 test runs on mega-brutal following this strategy, I win in around 275-400 days time, and the cure progress on 30-60%. This strategy heavily relies on the ATP Boost and Sympto-Stasis, and ignores the special traits that the Bio-Weapon provides entirely.

What if's:

Q: What if an island closes it's ports?

A: Do not panic, however, if 2 islands close their ports, reset. Immediately use all available dna points to buying extreme zoonosis, and use the bio-weapons special abilities and devolve extremely lethal symptoms, but don't do it too early, or else the cure will kill you.

Q: Since you have a lot of severe symptoms already, is it okay to leave something extra severe like necrosis?

A: No, even though the strategy is aggressive on severity, devolve any of the middle 6 symptoms (Which are Dysentery, insanity, total organ failure, coma, necrosis, and hemorrhagic shock), with the exception of possibly Dysentery

Strategy 5 (No Genes)

  1. Start in Saudi Arabia
  2. Evolve Gene Commpression 1 to 3
  3. Evolve Rash, Sweating, Skin Lessons
  4. Evolve Deactivate Modified Genes or Nucleic Acid Neutralisation if needed to remove lethality
  5. Evolve Cold Resistance 1, Drug Resistance 1, Genetic Hardening 1, Air 1, Water1, Air 2, Water 2, Drug Resistance 2, Cold resistance 2.
  6. Wait for more people to be infected (Somehow 80%)
  7. finish up the Deactivate Modified Genes and Nucleic Acid Neutralisation Branch.
  8. When the whole world is infected, evolve Unlock Annihilate Gene.

Strategy 6(speedrun no genes)

Difficulty: Causal--Brutal

Genetic codes wasn't tested in the run. But if you really want to, I'll recommend:

ATP Boost for basic evolution in early game

Base Oxidisation can be useful in some situations.

Aquacyte to get in to island countries easier

Extremophile to get anything, and to counter the debuff of Patho-Stasis. which wouldn't increase ability costs

Stage 1: spreading

Start in Saudi Arabia, immediately get Gene Compression 1 and 2

Get rash, sweating and Skin Lesions

Get Nausea, Vomiting and Diarrhoea. Get Deactivate Modified Genes 1 to counter the lethality

Then, go to transmission. Get Bird 1, Air 1, Air 2 and Water 1 by the order

If your plague has spread to Rich Countries, buy Drug Resistance 1

Your plague will get more lethality by now. Get Genetic ReShuffle 2 and 3, Deactivate modified genes 2, and possibly Nucleic Acid Neutralisation 1

Later, get symptoms like coughing and sneezing. Your plague will likely to get discovered.

Stage 2: Mid game

Your plague will get to more country, and cure progress should be starting now. Do NOT devolve mutated symptoms unless they got high severity

Get Water 2. Feel free to get Bird 2

The lethality will raise again now. Get Deactivate modified genes 3 and Nucleic Acid Neutralisation 2

Get even more tier 2 symptoms such as Abscesses, Hyper Sensitivity, Pneumonia

Get Cold Resistance 1 when cold climates were infected

Get Nucleic Acid Neutralisation 3 and Unlock Annihilate gene when all the countries are infected, no worries since infectivity outmatches the lethality

Stage 3: finish-off

Get transmission symptoms to avoid killing to fast. Such as Dysentery and Necrosis

If you don't feel safe, get Bird 2 and Livestock 1

If you want better results, get Insomnia, Paralysis, Seizures and Insanity to reduce cure progress

After a while, you will see "there are no healthy people left in the world"

Hurray! You have just won!


  • I found a major oversight by the developers that you can exploit on this plague type. It only works on Normal, and you need the gene Patho-Stasis. When you start the game, get your one DNA point from infecting your first country. Then go to the disease tab and go to the Abilities menu. Any of the three special abilities for the Bio-Weapon and then devolve it. You should have spent one DNA point on it and gotten back two. The Patho-Stasis gene keeps ability prices from going up as well. So with this you can continuously evolve and devolve it for more and more DNA points. You can also use this on the Bio-Weapon with the Spore Burst ability. -
    • On Normal, devolving doesn't seem to cost more. On Brutal, you'd need Translesion + though. And interestingly enough, the devolve counter is separate for each of the three tabs. - Tjmachado
      • This no longer works, since you only get one DNA point for devolving it. They also fixed it for the fungus: Spore Bursts cannot be devolved.
  • Activating Deactivate modified genes and Nucleic Acid Neutralisation will reduce the lethality bar and keep it down for a few days, enough for spreading to the last humans. -