Australian Encephalitis in Western Australia, 1978–1991

Abstract

ObjectiveTo review the various clinical manifestations of Murray Valley encephalitis (MVE) or Kunjin virus encephalitis in patients in Western Australia. DesignReview of clinical records, 1978 to 1991. PatientsOf 26 reported cases of Australian encephalitis, four were excluded from study because the patient's symptoms were not definitely associated with MVE virus or Kunjin virus infection. Two further cases of MVE were not reviewed as case records were not available. Of the remaining 20 patients, 18 had MVE and two had Kunjin virus encephalitis. ResultsSixteen cases were in the Kimberley, a tropical region where the viruses are endemic. Four were in the subtropical Pilbara and Gascoyne regions. Thirteen of the 20 cases were in Aborigines, of whom 11 were children. The seven non‐Aboriginal patients were adults. Seventeen of 20 cases were in males. The range of neurological disease and outcome was similar to that in previously reported cases, with convulsions, brainstem disease or respiratory failure in severe and fatal cases, and involvement of the spinal cord, cranial nerve or cerebellum in the moderate cases. One mild case without neurological involvement was caused by Kunjin virus. ConclusionsThe poor outcome in young Aboriginal children indicated that disease resulting from exposure early in life was more likely to be severe. The disease in adults, irrespective of racial background, was similar to that in cases reported previously from south‐eastern Australia, but generally milder.

Murray Valley encephalitis: Case report and review of neuroradiological features

“…The last epidemic occurred in the Murray Valley region of south‐eastern Australia in 1974 3 . Since then, it has occurred sporadic­ally throughout the tropical North of Australia, mostly in the Northern Territory and Western Australia 1,4 . Activity follows the monsoon rains 1 .…”

Genetic and phenotypic differences between isolates of Murray Valley encephalitis virus in Western Australia, 1972–2003

“…In recent years, MVEV activity has been detected as far south as the Midwest region of Western Australia (WA) [3,4]. Approximately 1:1000 infections with MVEV in humans lead to disease [5], although the clinical to subclinical infection rate is often higher in epizootic areas [6, C. Johansen and A. Broom, unpublished results].…”

Thymoma metastatic to the extradural spine

“…Up to two-thirds of patients with spinal epidural metastases will also have motor weakness at the time of diagnosis. 1 The more severe the neurologic deficit, the less the chance of complete recovery. Ability to walk at presentation is the most important prognostic factor.…”

“…6 His presentation was within the described incubation period of seven to 28 days. 1,7 In a review of clinical cases in the Northern Territory, 3 the presence of cranial nerve palsies, tremors or rigidity in adults was suggestive of MVE and reflected deep grey matter and brainstem involvement. In our patient the clinical features suggested HSE which is known to be the commonest identified cause of non-epidemic acute encephalitis in developed countries.…”