Hepatitis A is a disease caused by a RNA virus that is classified as a member of the picornavirus family. Hepatitis A virus (HAV) is usually transmitted by the fecal-oral route, most frequently via contaminated food or water or close contact. The virus is also associated with poor sanitary conditions and low socioeconomic status.
HAV causes an acute benign disease that is generally self-limited, rarely fatal and normally limited to the liver. Seventy percent of infected children less than 6 years old are asymptomatic and even when illness occurs, it is usually subclinical. On the other hand, in children above the age of 6, infection is usually symptomatic and accompanied by jaundice in more than 70% of cases. Typical symptoms last less than 2 months, yet prolonged or relapsing disease accounts for 10-15% of cases.
The case fatality ratio of Hepatitis A is estimated to be 0.3-0.6% and reaches up to 1.8% in adults older than 50 years of age. Patients with chronic liver disease who acquire hepatitis A are at an increased risk of acute liver failure disease.[6,7]
At this point there is no specific treatment for HAV infection. The Centers for Disease Control and Prevention (CDC) recommends the vaccination of all children at age 1 year as it is the most effective method to prevent hepatitis A infection.
Previous vaccination attempts to reduce the incidence of HAV infection were very successful. Universal vaccination programs had a positive impact not only on the vaccinated groups but also on nonvaccinated groups mainly due to a herd immunity effect. In the USA, Hepatits A vaccine was implemented in 17 states, decreasing the Hepatitis A rate by 88% to a historic low. Vaccination has proven to be safe with no increases in serious adverse events compared with baseline.
In Syria, vaccination against HAV is not included in the Extended and Routine Program on Immunization, and currently there is no recommended HAV vaccination strategy in Syria.
The status of Hepatitis A in Syria
In 2000, a study conducted in Syria on over 800 patients noted serologically that 89% were previously infected, with 95% of cases occurring in patients under the age of 15 years.
In different parts of the world, there has been a gradual shift in the age of acquiring HAV to older age groups. This shift has also been documented in most of Syria's neighboring countries.[14,15] This is mainly due to enhancing sanitation of the drinking water, increased promotion of personal hygiene measures reflecting an improvement in the socioeconomic conditions. The same applies for Syria; with the current development of better sanitation and living conditions, a shift in the age of infection to an older age group would be expected in the near future.