Background: Primary Human herpesvirus-7 (HHV-7) infection usually occurs during childhood and mainly causes exanthema subitum (Roseola infantum), followed by a lifelong latent state with possible reactivation in case of immunodeficiency. Occasionally, consequences of HHV-7 infection are reported in immunocompetent adults. The natural history of the infection is poorly studied, and little is known about its pathogenic role in central nervous system (CNS) disease in non-immune suppressed adults. Encephalitis results in substantial morbidity and mortality worldwide. Although rare, encephalitis follows infection with relatively common agents. CSF pleocytosis is suggestive of an inflammatory process and identification of a microorganism generally confirms a clinical diagnosis of encephalitis.

Case presentation: We describe here a case of probable encephalitis associated to HHV-7 with seizures in an immunocompetent patient. Clinical presentation and evolution may contribute to a better understanding of HHV-7 related pathology.

Conclusions: This case may alert clinicians to consider this specific etiology in the differential diagnosis of encephalopathy in patients with suspected infectious encephalitis. HHV-7 may be a pathological factor, and this etiology could be underestimated.