Hepatitis A is a Hepatotrophic virus that predominantly affects liver. Besides Hepatitis A, other Hepatotrophic viruses are Hepatitis B, Hepatitis C, Hepatitis D and Hepatitis E. All of them are contagious and some are life threatening too. Hepatitis A and E are waterborne; Hepatitis B, C and D are transmitted by bodily fluids (via syringes, needles, injections, toothbrush, razors).
Hepatitis A is the most common form of acute viral hepatitis worldwide. Nearly 119,000 cases of all cause viral hepatitis were reported in India in 2012. The Integrated Disease Surveillance Programme of the NCDC received notification of 290,000 cases of acute viral hepatitis in 2013. In addition to improving access to sanitation and clean drinking water, immunization plays an important role in prevention of Hepatitis A infection.
The virus is present in stools of infected person. It is also believed to have foodborne and water borne transmission, bloodborne transmission and perinatal transmission by contaminated maternal blood or feces intrapartum. Risk factors for HAV include socio economic status, household size, limited access to sanitation facilities, travel, immigration, intravenous drug use, homosexuality, and childcare employees. Millions of HAV infections occur worldwide annually.
Hepatitis A has worldwide but uneven distribution between geographical regions and population groups. About 15 years ago in India, the cord blood anti- HAV antibody levels in newborns was nearing 100 per cent, which in turn reflected the maternal antibody prevalence. In recent studies, this level has come down to 50-60 percent – reflective of good sanitation.
The incubation period is 15 to 45 days. It is unknown why hepatitis A is an age-dependent disease and most of children under six years of age develop subclinical or in apparent infections. Symptomatic hepatitis increases with age, being much more common in older children and adults. HAV infection is asymptomatic in 84% of children 1 and 2 years of age, 50% of children 3 and 4 years of age and 20 % of children over 5 years of age. Fifty percent of hepatitis A infections in adults above 60 years require admission. The case fatality which is 0.1% in children less than 15 years increases to 1.8% in patients above 50 years of age. The clinical illness starts with prodromal phase with symptoms of malaise, weakness, fever, anorexia and non-specific symptoms and lasts from a period of days to weeks. It is followed by an icteric phase lasting 2 to 4 weeks and is characterized by jaundice where the person turns yellow, the eyes and urine are prominently appearing yellow. During this phase bilirubin rises and can exceed 20 mg/dl and transaminases rise to a range of 500-2000 IU/L. In the final Convalescent phase of the disease, the virus is cleared, the patient recovers and biomarkers become normal.
Few patients develop relapsing hepatitis with worsening of jaundice and bilirubin even after it has started falling once. There could be a prolonged hepatitis A where the icterus may persist for even six months.
A small proportion of patients develops severe hepatitis and may develop fulminant hepatitis and acute liver failure (ALF). It can even cause acute on chronic liver failure (ACLF) in persons suffering from some form of chronic liver disease. In India, HAV forms the most common cause of ALF in pediatric age group below 10 years. Autoimmune hepatitis can be triggered by HAV infection in individuals with a genetic predisposition to the disease.
As there is no specific treatment the best alternative is prevention. It can be prevented by three general approaches. Because the predominant mode of HAV transmission is by poor sanitation, improving access to adequate hygiene and sanitation, including the appropriate disposal of human waste and provision of clean drinking water, is an important contributor to prevention of HAV. Good hand washing, can contribute to preventing transmission. Another modality is active immunization to those individuals at risk. Ask your doctor for a vaccination for yourself and your child if you are negative for protective antibody. A third approach is passive immunization with immunoglobulins only suitable after specialist consultations
If you are suffering from any of the above mentioned symptoms or would like to know more about the disease