Hepatitis is a misused term. Strictly speaking, it refers to any process which causes inflammation in the liver. These include viruses, bacteria, drugs, fungi, protozoa, congenital disorders and even the body's own immune system. The liver is an organ with many functions. It produces bile to aid in digestion, converts sugar to glucose and releases it into the blood as needed. It also synthesizes and releases certain proteins, some of which transport triglycerides, and metabolizes fat and cholesterol. In addition, it stores Vitamins A, B, D & K, as well as metals such as iron, hormones, and enzymes. We measure liver efficiency by determining enzyme levels found in the blood, such as AST, ALP, GGT and ALT. The liver also has a key role in detoxification and metabolism of drugs and toxins.
Nowadays, hepatitis is commonly used to refer to two forms of viral liver infection: B and C. There are at least five known viral agents which can attack the liver. Hepatitis A is spread by poor hygiene or ingesting contaminated food. It is usually benign and most people recover. It is rampant in poorer countries, and we often administer a vaccine to travelers to prevent it. Hepatitis B is transmitted by blood or sexual contact. It can be very serious and leads to cirrhosis and liver failure. In Ontario, all children in Grade 7 are eligible to receive vaccination with one or two booster shots. Hepatitis C is a similar blood transmitted disease caused by a different virus. Risk factors include IV (intravenous) drug use, pre-1992 blood transfusion, unhygienic tattoos and piercings, hemodialysis and others. 75% of people with Hepatitis C don't recover and go on to develop chronic infection with a risk of cirrhosis and cancer. There is no Hepatitis C vaccine yet. Hepatitis D is rarer, affects mostly IV drug abusers and occurs only in the presence of Hepatitis B. Hepatitis G is also rare, affecting hemodialysis patients.
It is most likely that the child in your question was probably afflicted with either Hepatitis B or C. In the case of Hepatitis B, your child can receive immunization sooner. In both cases, transmission is of very low risk in a normal school population. It could only occur in a case of blood transmission such as a bite, and not by saliva, tears or coughing. There are no reports that I could find documenting spontaneous spread in a school population.
● Viral Hepatitis. Information on Hepatitis A, B, C, D, and E from Centers for Disease Control and Prevention (CEC), National Center for Infectious Diseases (NCID).
● Hepatitis B. Fact Sheet from World Health Organization (WHO).
● Hepatitis E. Fact Sheet from WHO.
● Hepatitis A B C from New Zealand Ministry of Health.