Modifiers matching sickness:

• natural,
• big,
• serious,
• dangerous,
• related,
• widespread,
• physical,
• little,
• external,
• common,
• temporary,
• curable,
• preventable,
• acute,
• foreign,
• scary,
• fatal,
• basic,
• nasty,

Simple categories matching fatal:

• event,
• virus,
• illness,
• disease,
• situation,
• condition,
• infection,
• abnormality,
• cancer,
• trouble,
• error,
• disaster,
• weapon,
• complication,
• ailment,
• sickness,
• malignancy,
• consequence,
• pathology,
• disorder,
• accident,
• symptom,
• result,
• injury,