The following is a list of, as well as an overview of, symptoms in the Simian Flu DLC:


The Simian Flu, like standard plague types, starts off with six symptom trees. However, the most notable of these six trees is the Neuro-enhancement 1 tree, which is separate from its peers, and does not connect with the web. What is surprising about these symptoms is that they greatly increase human intelligence and help humans create a cure at a higher speed, unlike any symptoms before them. However, at Neuro-enhancement 3, very small numbers of casualties start appearing, and, at Total Brain Death, it kills in large numbers.

It also has symptoms that were previously only in the Smallpox, Swine Flu, and Nipah Virus scenarios: Headache, Subconjunctival Bleed, Pharyngitis, Meningitis, and Haemoptysis. It also introduces the symptoms Joint Pain, Epistaxis, Gastric Ulceration, Hydrocephalus, Hypocoagulability, and Subconjunctival Haemorrhage.


Symptom Description Base Cost Infectivity Severity Lethality Change to cure requirement


Sensitivity and pain when eyes exposed to sunlight. Slows future research speed but slightly reduces infection rates





0.02 (0.01 Change to Research Efficiency)

Subconjunctival Bleed Blood gathering in the anterior chamber of the eye gives a red appearance to the iris or cornea. Decreases cure speed. 4 2 6 0

0.01 (0.025 Change to Research Efficiency)

Subconjunctival Haemorrhage Blood vessels between conjunctiva and sclera burst, causing severe red eyes with occasional external bleeding. Decreases future research speed. 6 3 7 0 0.01 (0.05 Change to Research Efficiency)
Blindness Severe bleeding in the retina causes blindness. Significantly decreases research speed. 6 0 18 0.01 0.01 (0.15 Change to Research Efficiency)
Rash The skin becomes blistered and painful, slightly increasing infectivity 4 2 2 0 0.01
Joint Pain  Inflammation in the joints causes pain when moving. Decreases chance of infection due to reduced movement. 1 -5 4 0 0.01
Hydrocephalus Cerebrospinal fluid accumulates in cavities in the brain, increasing intracranial pressure. Highly lethal without treatment 16 1 11 8 0.01
Hypocoagulability Significantly reduced blood clotting ability results in heavy external bleeding. Often fatal due to exsanguination 23 4 10 9 0.01
Internal Haemorrhaging Flesh eating pathogens breaks down arterial membranes causing rapid internal bleeding and death 16 0 9 8 0.01
Headache Disturbance of the pain-sensitive structures around the brain. Reduces concentration. 4 1 2 0 0.01 (0.02 Change to Research Efficiency)
Fever Increase in temperature, contagiousness and severe dehydration, which can be fatal 7 4 6 1 0.01
Coma Neuropathic effects in the brain stem cause loss of consciousness and sometimes death. Significantly harder to cure 31 0 18 3 0.24
Meningitis Acute inflammation of the protective membranes covering of the brain and spinal cord. Highly fatal 31 0 16 15 0.01
Neuro-enhancement 1 Virus able to enter brain cells and modify DNA, improving existing neural pathways. Increases human intelligence. 4 0 1 0 (0.5 Change to Mutation Likelihood) -0.15 Change to Research Efficiency
Neuro-enhancement 2 Virus able to further modify brain cell DNA, triggering development of new neural pathways. Increases human intelligence. 5 0 1 0 (0.5 Change to Mutation Likelihood) -0.25 Change to Research Efficiency
Neuro-enhancement 3 Virus aggressively manipulates brain cell DNA, accelerating neural growth. Increases intelligence but with chance of immune response 6 0 1 1 (0.5 Change to Mutation Likelihood) -0.45 Change to Research Efficiency
Total Brain Death Comprehensive replacement of brain cell DNA triggers massive immune response, leading to complete and irreversible loss of brain function. 7 0 20 30 0
Pharyngitis Sore throat causes discomfort and increases likelihood that coughing will spread disease 1 1 2 0 0
Coughing Chance of infection by spreading pathogen into surroundings. especially in high density, urban areas 4 3 2 0 0.01
Sneezing Fluid discharge through sneezing greatly increases infection rates. 7 5 2 0 0.01
Epistaxis Haemorrhage of the nasal mucous membranes cause severe nosebleeds, increasing likelihood of infection 4 5 7 0 0.01
Haemoptysis Coughing up blood from inflamed bronchi increases infectivity and is fatal in extreme cases. 12 7 8 2 0.01
Hemorrhagic Shock Severe loss of blood volume causes oxygen deprivation, loss of consciousness and death 31 0 12 15 0.01
Pneumonia Serious fluid build and discharge from the lungs. People in cold climates especially vulnerable 3 3 5 0 0.01
Pulmonary Hemorrhage Severe bleeding in the upper respiratory tract and the trachea. Increasing infectivity and often fatal. 24 5 13 9 0.01
Nausea Irritated stomach lining leads to discomfort. Slight chance of infection when kissing. 2 1 2 0 0.01
Vomiting The expulsion of infected material through projectile vomiting increases the risk of infection. 4 3 3 0 0.01
Diarrhoea Pathogen active in digestive tract, causing infection through faeces and potentially lethal dehydration. Poor countries v. vulnerable. 11 6 6 2 0.01
Dysentery A complete breakdown in the digestive tract causes infected sewage, dehydration, starvation and death 22 8 13 7 0.01
Gastric Ulceration Multiple sores develop in the lining of the stomach, causing severe pain in the abdominal region. Can be lethal 13 3 7 5 0.01
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