Disease/ syndrome Outbreak weekly threshold (UNHCR) Incubation period (WHO)
Acute Jaundice Syndrome NA 2-10 weeks
Cholera 1 case 2 hours to 5 days
Dengue Fever NA 4-10 days
Giardiasis NA 5-25 days
H1N1 NA 1-4 days
Hepatitis E NA 2-10 weeks
Influenza Like Illness NA 4-6 days*
Measles 1 case 10-18 days
Meningitis 5 cases or 1 confirmed Meningococcus or 5 cases or 1.5 times the baseline 2-10 days
Pertussis NA 6-20 days
Poliomyelitis 1 case 4-35 days
Rubella NA 5 days to 3 weeks
Shigella NA 1-4 days
Varicella NA 10-21 days
Watery Diarrhea 1.5 times the baseline 1-10 days