The continuing issues surrounding hepatitis B
Hepatitis Roger Williams CBE, from The Institute of Hepatology London and Foundation for Liver Research, highlights two issues that require urgent resolution.
"The two continuing issues that I would like to comment on and do require urgent resolution are as follows:
Tests for immigrants
"Firstly, the lack of any testing for hepatitis virus infections of applicants coming into the country. This is compulsory in many countries around the world including Australia and America. These immigrants are often from areas of high HBV prevalence and bring with them the HBV virus. This is why the greatest concentrations of HBV infections are found in immigrant communities in the UK.
"It was proposed that a mandatory test for HBV should be included as part of visa application."
"The proposal put forward some years ago was that a mandatory test for HBV should be included as part of the application for getting a visa. However, despite much support, this was rejected which means that applicants who are positive for the infection are not diagnosed until they develop clinical symptoms – often too late with cirrhosis or primary hepatocellular carcinoma (HCC). It also means that there is no firm data as to the number of chronic infected cases in this country – variously estimated at between 200,000 to 300,000 subjects.
"If pre-visa testing was carried out those found to be positive could be treated with antiviral drugs (Entecavir or Tenofovir) which would lower their infectivity to others when they settled in the UK."
Proper use of antiviral drugs
"The second issue that needs to be stressed is that the chronically infected cases that do get antiviral treatment with Entecavir or Tenofovir do well in that the associated inflammation and liver damage is usually very well controlled. If the treatment is started early at the stage of chronic hepatitis, the development of cirrhosis can be prevented.
"Even treated cases remain potentially infectious, because of persistence of HBV DNA in the liver's cells."
"The introduction of these drugs has led to a fall in the number of cases of end-stage cirrhosis from HBV infection requiring liver transplantation. However, these cases remain potentially infectious, because of persistence of HBV DNA in the nucleus of the liver cell. Since infection can be reactivated with immunosuppressive drug therapy and although the risk of developing HCC is reduced, a tumour can still develop.
"There are also no clear guidelines in this country as to how long such antiviral treatment should be continued and these patients need to be monitored in liver clinics by blood tests and ultrasound or other imaging modalities at regular 6 – 12 monthly intervals.
"Finally, although much work is being done by ‘big Pharma’ on new agents to eradicate HBV DNA completely from the liver, these are some way off clinical introduction and the initial results of the entry inhibitor category of drugs have not been encouraging. It will be some years, before one will be able to talk of a cure for HBV infection."