Subacute sclerosing panencephalitis: current threat

Abstract

The relevance of this problem is associated with a predicted increased incidence of subacute sclerosing panencephalitis, a steadily progressive and difficult to diagnose fatal brain disease. Subacute sclerosing panencephalitis develops after measles and it does not correlate with clinical type of an acute measles infection: it affects both persons with manifest measles and ones who have had an asymptomatic or abortive disease. WHO estimates the incidence of subacute sclerosing panencephalitis as 4–11 per 100,000 measles cases. The latency period from measles to the onset of subacute sclerosing panencephalitis is between 2.5 and 34 years. As a result of measles outbreaks in 2011–2014 and 2017–2019 an increase in the number of subacute sclerosing panencephalitis cases in Russia is expected soon. Diagnostic difficulties are caused by multiplicity of subacute sclerosing panencephalitis clinical manifestation and the absence of MRI changes in early stages. Thereby, it is important to exclude SSPE in patients with neurological symptoms. Screening tests for subacute sclerosing panencephalitis should be conducted in children with acute cognitive impairment, myoclonus, or a new onset of epileptic syndrome. The specific cure for subacute sclerosing panencephalitis has not been developed yet. Most treatments aim at reducing symptoms. Up to date, the only way to conquer this disease is routine measles vaccination.