MCQ of the Day: 3 November 2026

Hydrophobia following an untreated dog bite is classic encephalitic (furious) rabies, caused by rabies virus (genus Lyssavirus, family Rhabdoviridae); India carries a large share of the world's rabies deaths. Negri bodies are eosinophilic intracytoplasmic inclusions made of viral nucleocapsid aggregates, best seen in hippocampal pyramidal neurones and cerebellar Purkinje cells, with characteristic inner basophilic granules. They are pathognomonic but absent in a proportion of cases, so the direct fluorescent antibody test on brain tissue is the reference diagnostic method, and RT-PCR on saliva or nuchal skin biopsy is used ante-mortem.
A (Guarnieri bodies): eosinophilic intracytoplasmic inclusions of poxviruses (vaccinia, variola) in epithelial cells, not neurones.
B (Councilman bodies): apoptotic, eosinophilic hepatocytes seen in yellow fever and viral hepatitis.
D (Henderson-Patterson bodies): large intracytoplasmic inclusions in keratinocytes in molluscum contagiosum.