The patient was placed on immunosuppressant drugs and showed persistently abnormal liver function tests results.
The world's first human case of rat disease has been diagnosed in China.
Dr. Yuen Kwok-yung, chairman of the infectious diseases section of the microbiology department at the University of Hong Kong, called the case "a wake-up call".
The full extent of the rat-specific version of hepatitis E is not fully known, aside from what was observed in the patient.
Hepatitis E in rats has a different genetic signature than the human strain, so it's probably not something that routine testing can detect, Adalja said. It was described as being "highly divergent" from the strain seen among infected humans. But viruses are said to be the most common cause around the world.
Humans tend to be infected by ingesting infected faecal matter, such as drinking contaminated water or through contact with poor sanitation. In rare cases, it can also cause liver failure and death. The virus is a liver infection that can cause fever, abdominal pain and jaundice. The animal form of the disease is thought to infect wild boars, domestic pigs and deer, as well as rats and other rodents.
It can not be spread through sex or sharing needles like other forms of the virus, but has been caught from blood transfusions and organ transplants in the past.
The man is said to be recovering.
There is no treatment for hepatitis but it usually clears up by itself.
There are five types (namely A, B, C, D, and E) of viral hepatitis, which can be spread by various means such as food contamination, sexual intercourse, sharing needles, pregnancy, and childbirth.
The human form of hepatitis E is generally transmitted through contaminated water and is guesstimated to infest 20 million people worldwide, consequential of 3.3 million people showing symptoms each year as per the World Health Organization.
Cases of HEV typically present in one of two ways, either as large outbreaks and sporadic cases in areas where HEV is endemic (genotype 1) in Asia and Africa, (genotype 2) in Mexico and West Africa and (genotype 4) in Taiwan and China or as isolated cases in developed countries (genotype 3), reports the WHO.