POST VACCINAL SYNDROME

POST VACCINAL SYNDROME 

SOWNDHARYA S - MDCCC-137 

With the exception of having recently received a smallpox vaccination, post-vaccination encephalitis is a disease with an unknown etiology that has recently been identified. PVE is fatal in about 43% of cases and is accompanied by pathological changes in the central nervous system. PVE symptoms first appear between the 8th and 14th day following vaccination which includes fever, headache, disorientation, and nausea. Lethargy, convulsions, polyneuritis, seizures, memory impairments, localized paralysis, and hemiplegia develop over time. PVE may rarely result in coma and death. Histologically, the spinal cord and the brain both exhibit inflammatory extra-adventitial lesions. In the acute or subacute phases, lesions can either be uniform or dispersed. The majority of the damage is found in white brain matter. T cells, plasma cells, and phagocytic cells infiltrate the meninges. Only in severe lesions were polymorphonuclear cells found. Aside from cellular infiltrates in the perivascular space, there is tissue rarification in areas near damaged blood vessels. There is significant demyelination with rapid clearance of degraded myelin. Tissue damage eventually leads to necrosis. One death per million vaccinations is the generally accepted rate of deaths following live vaccine administration. However, several vaccination strains were used during the smallpox eradication campaign, and these strains varied greatly in how often they caused negative side effects. Vaccinia immunoglobulin was administered to PVE patients. This treatment's most notable effects were only seen when administered prior to the onset of PVE. Because of this, patients with PVE received only supportive care in an effort to lessen symptoms.