An Australian man’s dream vacation in Asia turned into a nightmare after he got bit by a mosquito and contracted a potentially deadly virus that robbed him of his memory, news.com.au reported.

In January, 45-year-old Mark Schroeder visited Bali and contracted the rare condition Japanese encephalitis, which is fatal in up to one in four cases. The virus is attacking areas of Schroeder’s brain that control short-term memory, but it can also cause long-term memory loss.

Doctors initially believed that Schroeder, who was suffering from flu-like symptoms, may have contracted dengue fever, typhoid or malaria, according to news.com.au. His partner, Ann-Marie Freeman, called an ambulance on the morning of Monday, Jan. 5 after finding Schroeder in the same position she had left him sitting in the night before.

Schroeder then spent seven weeks in Monash Medical Centre where he started suffering from delusions and had to be constantly reminded of where he was.

“We would explain to him that he was in Melbourne, [Australia], in hospital, and reorient him,” Freeman told news.com.au.

“But with no short-term memory, five minutes after you’d given him the reassurance that he was home and safe, he would forget and go straight back into anxiety,” she told the news site.

Doctors aren’t certain if Schroeder will fully recover and have no definite timetable for his improvement.

“I just doubt everything … I have lost my memory,” Schroeder told the Herald Sun.

For now, he has returned home where Freeman is helping to care for him. Friends and family are hosting a fundraiser for him in April to help cover medical costs.

According to the Centers for Disease Control and Prevention (CDC), Japanese encephalitis virus is the leading cause of vaccine-preventable encephalitis in Asia and the western Pacific. While the risk for travelers to Asia is low, it varies based on destination and activities. It is maintained in a cycle involving mosquitoes, pigs and wading birds.

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