Hepatitis E virus (HEV) is one of the most common causes of viral hepatitis globally. The infection is particularly severe in immunocompromised persons such as transplant recipients in whom infection can turn chronic. Fortunately, chronic hepatitis E is treatable with oral ribavirin. In 2018, we discovered for the first time that rat hepatitis E virus, a highly prevalent pathogen in street rats, can infect humans. This discovery subsequently enabled clinical recognition of rat hepatitis E as the causative pathogen in patients with unexplained hepatitis, many of whom could be cured with antivirals. We also discovered that the most common cause of human hepatitis E in Hong Kong (Paslahepevirus balayani genotype 4), which is a foodborne infection from swine, frequently causes chronic infections in immunocompromised patients that progress to liver fibrosis and cirrhosis if left untreated.
This presentation will detail the evolution and development of hepatitis E clinical services in the Hospital Authority. The diagnostic algorithm of hepatitis E in Hong Kong has historically been limited to IgM antibody testing, which is insensitive for diagnosis of rat hepatitis E and chronic HEV infections. Therefore, we developed quantitative RT-PCR assays for HEV that have since been adopted by Hospital Authority. These tests have filled the gap for diagnosis of hepatitis E, public health surveillance of rat hepatitis E (with demonstrable impacts on patient health and rodent disinfestation efforts in the city), and monitoring of chronic hepatitis E infection in transplant recipients. We have also set up genotypic resistance testing for management of challenging cases of ribavirin-refractory hepatitis E. We provide specialist consultation services for hepatitis E in immunocompromised persons on inpatient, outpatient, and telephone consultation basis. Our clinical services have incorporated innovative bench-to-clinic solutions such as the world's first application of molnupiravir, a SARS-CoV-2 drug, for the treatment of chronic hepatitis E.
