Pattern of viral hepatitis infection in a selected population from Saudi Arabia

Military Medicine, Jul 2003 by Qasim, Laila, Abed, Eman, Memish, Ziad, AlBasheer, Amal, Et al

Viral hepatitis is an important health problem worldwide. Globally, three major viruses are the leading cause of hepatitis: hepatitis A, B, and C. In this study, we have investigated the pattern of hepatitis among the National Guard personnel and their extended families seen in the central region of Saudi Arabia. The most dominant type of hepatitis infection was hepatitis B virus (HBV), followed by hepatitis C virus (HCV), and to a lesser extent hepatitis A virus (HAV). Our results showed three different age groups at risk of acquiring the infection: HAV, which is mainly a disease of the young; HBV, a disease of adolescents and adults; and HCV, a disease of the elderly. There was no significant difference in the male:female ratio in HAV and HCV; however, as seen in the developed countries, more males were affected with HBV than females. These data will pave the way for further studies by identifying the risk groups for the three major hepatitis infections and by using the data as a preventive tool to educate those risk groups.

Introduction

Viral hepatitis is a major health burden worldwide and represents a significant cause of morbidity and mortality. Different viruses can cause hepatitis, the most common and important viruses being A, B, C, and E. One of the main differences among these viruses is the way they spread. In Saudi Arabia, viral hepatitis is a notifiable disease.

Hepatitis A has a worldwide distribution. It spreads through the fecal-oral route and is considered the most common type of viral hepatitis. Lower socioeconomic classes are more frequently affected with the virus because of overcrowding and poor sanitation. Classically, it is a childhood disease that is related to bad sanitation and hygiene.1 The epidemiology of hepatitis A virus (HAV) is rapidly changing. In Saudi Arabia, the presence of HAV-IgG declined from 50% in 1989 to 24.8% in 1997; this could be attributed to the improvement in hygiene and sanitation practices.2

Hepatitis B (HBV) is a major public health problem worldwide. About one-third of the world's population has already been infected with HBV, and it is estimated that 350 million people are chronic carriers.3,4 Risk factors for HBV infection include injection drug use (IDU), multiple sex partners, sexual contact with hepatitis carriers, homosexual activity, and tattooing and body piercing.5,6 Acute infection with HBV is usually asymptomatic in infants and children,7 unlike adults where 30 to 50% develop symptoms after infection. Age of onset is considered one of the major risk factors of developing chronic HBV infection; the younger the age of onset the higher the risk of developing chronic HBV infection. About one-fourth of hepatitis B surface antigen (HbsAg) carriers will develop cirrhosis and at a later stage about 5% of them will develop hepatocellular carcinoma.8

HBV infection is endemic in Saudi Arabia, where infection is transmitted horizontally early in life.9,10 A mass vaccination program was started in 1989 in the Kingdom11 and all infants are being vaccinated. In the 8 years following the mass vaccination, HbsAg carrier rates were reduced from 6.7% to 0.31%.2

Hepatitis C (HCV, formerly non-A, non-B) was only recently discovered in 1988. HCV is the most common viral hepatitis in the United States and is the leading cause of cirrhosis and end-stage liver disease.12 Risk factors for HCV infection include IDU, history of blood transfusion or receipt of blood products prior to 1990, sexual contact with an IDU person, occupational blood exposure, and a history of surgery.13 Data from Saudi Arabia snowed a 1 to 5% prevalence of HCV antibodies in blood bank donors and community studies.14,15

In this study, we investigated the characteristics of patients suffering from hepatitis who were referred to the National Guard Hospital or its satellite clinics in Riyadh. Hepatitis A, B, and C serology were investigated and results from 3 years were analyzed.

Materials and Methods

Subjects

King Fahad National Guard Hospital is a tertiary referral hospital primarily serving the Saudi Arabian National Guard soldiers and their eligible dependents. It is also a referral center to several primary health care centers in the Saudi Arabian National Guard. Samples of A, B, and C serology were analyzed for the 3 years (1999-2001). Table I shows the total number of requests for each hepatitis marker with the number of positive individuals and percent positive of the total. This is not a prevalence study, but investigates the total number of individuals tested for the virus each year and percent positive in our hospital. Our report concentrates only on the analysis of the positive results.

Immunoassays

Both hepatitis A IgM-specific antibodies and HbsAg were assayed on Axsym (Abbot Laboratories, Chicago, Illinois). This is a Microparticle Enzyme Immunoassay technology. Briefly, analytes (HbsAg or anti-HAV IgM antibodies) bound to the microparticles coated with a capture molecule (antigen, antibody, or viral particle) creating an immune complex Alkaline phosphatase-labeled conjugate was added to the matrix cell which would bind to the immune complex to complete the antibody-analyte-conjugate "sandwich." 4-Methylumbelliferyl phosphate substrate was added, and the alkaline phosphatase would catalyze the hydrolysis of 4-methylumbelliferyl phosphate to 4-methylumbellipherone. The rate of 4-methylumbellipherone generation is proportional to the analyte concentration.