• Etiological Agents of Viral Hemorrhagic Fevers:
• VHFs are severe zoonotic syndromes caused by enveloped RNA viruses belonging to four major taxonomic families:

• Flaviviridae: Yellow fever virus, Dengue virus, Kyasanur Forest Disease (KFD) virus.
• Filoviridae: Ebola virus, Marburg virus.
• Bunyavirales (Bunyaviridae / Nairoviridae / Hantaviridae): Crimean-Congo Hemorrhagic Fever (CCHF) virus, Rift Valley Fever virus.
• Arenaviridae: Lassa fever virus, Junin virus.
  • nalysis:

• All listed families cause viral hemorrhagic fevers. Hence, Option 1 ((A), (B), (C) and (D)) is correct.

• WHO / WOAH Gold Standard for Rabies Diagnosis:
• The Direct Fluorescent Antibody Test (dFAT) performed on fresh brain impression smears (hippocampus / Ammon's horn, cerebellum, and medulla oblongata) is universally recognized by the WHO and WOAH as the gold standard test for rabies diagnosis in postmortem animal brains.
• It utilizes FITC-conjugated anti-rabies monoclonal or polyclonal antibodies to detect rabies nucleoprotein (N protein) antigen with sensitivity and specificity approaching $99-100\%$.
• nalysis:
• (Fluorescent antibody test): Correct.

Correct option: (4) Fluorescent antibody test

• Japanese Encephalitis Virus (JEV, Flaviviridae):
• Vector: Transmitted primarily by zoophilic mosquitoes belonging to the genus Culex (Culex tritaeniorhynchus, C. vishnui), which breed in flooded rice paddies. (Tick transmission by Haemaphysalis is characteristic of Kyasanur Forest Disease, not JE; Statement A is False).
• Amplifier Hosts (B): Pigs develop high-titer viremia without clinical illness, serving as the essential amplifying host that multiplies the virus in agricultural communities.
• Dead-End Hosts (C & D): Humans and Horses develop clinical encephalitis with transient, low-titer viremia that is insufficient to infect feeding mosquitoes, terminating the transmission chain.
• nalysis:
• Statements (B), (C), and (D) are true. Hence, Option 2 is correct.