| STEP 2: History of fever and clinical features | ||
|---|---|---|
| A. FEVER PATTERN | Daily / Continuous | Common: malaria, travellers’ diarrhea, RTI, enteric fever |
| Uncommon: rickettsioses | ||
| Rare: HIV, Q-fever, brucellosis, TB | ||
| Saddleback (biphasic) | Common: malaria, dengue | |
| Uncommon: leptospirosis | ||
| Rare: yellow fever, arbovirus | ||
| Relapsing | Common: malaria, enteric fever | |
| Uncommon: amoebic liver abscess, leptospirosis | ||
| Rare: HIV, Q-fever, brucellosis, TB, endemic mycoses, borreliosis | ||
| B. INCUBATION PERIOD (DEFINITION: TIME FROM EXPOSURE / INFECTION TO DISEASE MANIFESTATION) | <2 weeks | Common: malaria, travellers’ diarrhea, dengue, RTI, influenza |
| Uncommon: rickettsioses, meningitis | ||
| Rare: yellow fever, arbovirus, viral hemorrhagic fever | ||
| 2-6 weeks | Common: malaria, enteric fever | |
| Uncommon: hepatitis A virus (HAV), katayama fever, amoebic liver abscess, hepatitis E virus | ||
| Rare: HIV, Q-fever, brucellosis, East African trypanosomiasis | ||
| >6 weeks | Common: malaria | |
| Uncommon: HBV, amoebic liver abscess, TB | ||
| Rare: HIV, visceral leishmaniasis, endemic mycoses, West African trypanosomiasis, HCV | ||
| C. FEVER DURATION AT VISIT | <7 days | Common: malaria, travellers’ diarrhea, dengue, enteric fever, RTI |
| Uncommon: rickettsioses, leptospirosis, meningitis | ||
| Rare: yellow fever, arbovirus | ||
| 7-21 days | Common: malaria, enteric fever | |
| Uncommon: rickettsioses, viral hepatitis, leptospirosis | ||
| Rare: HIV, Q-fever, brucellosis | ||
| >21 days | Common: malaria, enteric fever | |
| Uncommon: TB, HBV, bacterial endocarditis | ||
| Rare: HIV, Q-fever, brucellosis | ||
Arbovirus: includes other mosquito-borne viruses such as chikungunya, mayaro, O’nyong-nyong, Ross River, sindbis, equine encephalitis, WNV, La Crosse, Oropouche, Rift Valley fever, and tick-borne viruses such as Kyasanur Forest, Omsk, and Crimean-Congo hemorrhagic fever