'More than devastating'-patient experiences and neurological sequelae of Japanese encephalitis§

Abstract

Background: Japanese encephalitis (JE), caused by the mosquito-borne JE virus, is a vaccine-preventable disease endemic to much of Asia. Travellers from non-endemic areas are susceptible if they travel to a JE endemic area. Although the risk to travellers of JE is low, the consequences may be severe.

Methods: Here, we describe three cases of JE in British travellers occurring in 2014-15. In addition, we report, through interviews with survivors and their families, personal experiences of life after JE.

Results: Three cases of JE were diagnosed in British travellers in 2014/15. One was acquired in Thailand, one in China and one in either Thailand, Laos or Cambodia. All three patients suffered severe, life-threatening illnesses, all were admitted to intensive care units and required medical evacuation back to the UK. One patient suffered a cardiac arrest during the acute stage but made a good recovery. The other two patients remain significantly paralysed and ventilator dependent. All three cases had clear indications for vaccination, and all have been left with life-changing neurological sequelae.

Conclusions: Travel health providers should be aware of the severity of JE, as well as the risk, allowing travellers to make fully informed decisions on JE vaccination.

Keywords: JE; JE vaccine; JE virus; Japanese encephalitis; Japanese encephalitis vaccine; Travel medicine; Traveller.

Figure 1

Map of the travel destination of the three cases, including medical evacuation routes within Asia

Figure 2

Neurological imaging of Patient two. (A), MRI scan performed in Bangkok on 18 July 2015 showing bilateral thalamic lesions, worse on the right (arrow). (B and C), MRI scan in Liverpool on 4 August 2015 showing persistent thalamic lesions (B, arrow) and high signal in the spinal cord (C, arrow)

Figure 3

MRI of Patient three. (A), FLAIR images from an MRI scan performed in Bangkok on 5 August 2015 showing symmetrical high signal affecting the thalami and lentiform nuclei bilaterally. Evidence of radiosurgery to the left basal ganglia arteriovenous malformation with associated encephalomalacia within the left cerebral white matter and some haemosiderin deposition from the arteriovenous malformation is seen. (B), The abnormal area extends into the medial temporal lobes, the cerebral peduncles and into the brain stem