Grantham Hospital, Aberdeen. Photo: Wikimedia Commons

A 52-year-old man who was the third person diagnosed with Japanese encephalitis in Hong Kong this year might have been infected through a blood transfusion.

In May, the man underwent a lung transplant, after which he stayed in Grantham Hospital in Wong Chuk Hang, RTHK reported. On July 6, he received a blood transfusion but then contracted a fever.

He was later transferred to the intensive care unit at Queen Mary Hospital and remained in critical condition. This Thursday, he was diagnosed with Japanese encephalitis, according to the Centre for Health Protection.

Whether the man contracted the disease through the blood transfusion or from mosquito bites remained unclear, the center said.

However, the Red Cross confirmed that a blood bag used during the transfusion had tested positive for Japanese encephalitis, Apple Daily reported, citing an unnamed source.

The Red Cross said it had run tests on donors’ blood for many diseases but not Japanese encephalitis. It only asked donors through questionnaires whether they had been to countries with serious mosquito problems.

On Friday, the Food and Environmental Hygiene Department sent staff to kill off mosquitoes in areas near Grantham Hospital.

Read: Man diagnosed with Japanese encephalitis after mosquito bites

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