Monday, July 28 marks World Hepatitis Day, a global public health campaign led by the WHO to raise awareness about the five hepatitis viruses (A, B, C, D, and E). Through this campaign, the WHO urges people worldwide to “think again” about hepatitis, an often neglected but potentially deadly group of viruses that kills almost 1.4 million people every year. The five hepatitis viruses cause acute and chronic liver disease. Hepatitis A and E (HAV, HEV) are usually acute, causing symptoms such as jaundice, abdominal pain, vomiting, loss of appetite, fever, and an enlarged liver. Though HAV and HEV are not usually fatal, infection can lead to acute liver failure, which may be deadly. Of the approximately 20 million people who are infected with HEV each year, 3 million develop inflamed livers and 56,600 die. An additional 1.4 million people are infected with HAV every year. These two viruses spread through contaminated food and water and are especially prevalent in rural areas of developing countries, where sanitation may be inadequate.