Hepatitis A is the most prevalent type of hepatitis. Hepatitis A and hepatitis E are mainly transmitted through the fecal-oral route, while hepatitis B, C, and D are spread through blood or other body fluids.
Hepatitis A (HAV) is a highly contagious virus that attacks the liver. It is the seventh most commonly reported infectious disease in the United States (behind gonorrhea, chicken pox, syphilis, AIDS, salmonellosis, and shigellosis). HAV accounts for as many as 65 percent of all viral hepatitis cases in the U.S. each year.
In 1996, approximately 29,000 cases of HAV were reported in the U.S. However,the Federal Centers for Disease Control and Prevention (CDC) estimate that there are approximately 143,000 HAV infections in the United States each year. Worldwide, there are an estimated 1.4 million cases reported annually.
There are several types of hepatitis. Hepatitis A is the most prevalent. Hepatitis A and hepatitis E are mainly transmitted through the fecal-oral route, while hepatitis B, C, and D are spread through blood or other body fluids.
Common Symptoms of Hepatitis A
— pain in the liver area
— dark urine
— light-colored stools
— abdominal pain
There is currently no treatment for hepatitis A, although rest and proper nutrition can relieve some symptoms. The most important factor affecting the severity of the disease is age. Children less than a year old rarely show clinical signs of the illness. This means that parents and child-care workers handling soiled diapers can catch or transmit the disease without knowing they have been exposed.
Clinical manifestations of hepatitis A often pass unrecognized in children younger than two years of age. Overt hepatitis develops in the majority of infected older children and adults. In adults, approximately 22 percent will be hospitalized.
An estimated 100 deaths occur in the U.S. each year from hepatitis A. In out breaks, three people died in northern California in December, 1995, and another person died in Canada in January, 1996.
The incubation period for hepatitis A ranges from 20 to 50 days , which means that infectious patients, such as food handlers or children, can spread the disease well before they are even aware they have it. Incubation is shorter with increasing age.
Most patients begin recovery within three weeks, although some have prolonged or relapsing symptoms for up to six months.
How Is Hepatitis A Spread?
The hepatitis A virus is transmitted by the fecal-oral route, through close person-to-person contact, or by ingesting contaminated food or water. Infection has been shown to be spread by:
— close personal contact with someone infected with hepatitis A.
— eating foods contaminated by infected food handlers.
— contact with infected children (who do not usually show symptoms), who can then infect non-immune children or adults at home or in child-care centers.
— ingesting raw or undercooked shellfish (e.g. oysters, clams, mussels) from waters contaminated with the hepatitis A virus.
— ingesting contaminated food or water during travel to underdeveloped areas.
— transmission through blood transfusions or sharing needles with infected people using injectable drugs.
In the United States and other developed countries, people potentially susceptible to catching hepatitis A include:
— those who travel to less developed areas of the world where hepatitis A is common. These areas include Africa, Asia (except Japan), the Mediterranean basin, Eastern Europe, the Middle East, Central and South American, Mexico andparts of the Caribbean.
— military personnel
— individuals living in areas where hepatitis A is endemic
— certain ethnic and geographic populations that experience cyclic epidemics
— male homosexuals and others who engage in high-risk sexual activity
— hemophiliacs and other recipients of therapeutic blood products
— youngsters in child-care facilities, their families, and facility staff
— food handlers
— healthcare workers who treat patients infected with the virus
— institutionalized persons and their caregivers
— laboratory workers who handle live hepatitis A virus
— handlers of primates that may harbor hepatitis A.
Also at risk are people who live in frequently affected communities with poor sanitation or overcrowded living conditions.
Why Worry About Children?
The highest incidence of hepatitis A is in children. Nearly 30 percent of the reported cases occur in children younger than 15. Many very young children do not show symptoms, so the unreported number is likely much higher.
Many health experts suggest that children are a silent source in spreading the disease. Approximately 45% of persons with HAV cannot identify a recognized risk factor associated with their disease, but about half of them have children under five years of age living in their households.
How Can Hepatitis A Be Prevented?
Historically, the most common preventative has been immune globulin administration, which is effective for about three to six months. Now, however,there are two vaccines that provide longer-term protection and eliminate the need for repeated shots. These vaccines typically are administered as oneinitial shot followed by a booster shot in about six to 18 months.
Prior infection with hepatitis A confers lifetime protection against a second attack. If in doubt, a blood test can determine if an individual has had hepatitis A in the past or needs protection.
What Is The Economic Impact Of Hepatitis A?
The annual direct and indirect costs of treating cases and controlling outbreaks of hepatitis A in the United States are estimated to be $200 million. Additional economic costs are incurred when adults who contract the disease miss an average of 27 days of work, which translates into approximately $2600 in lostwages for each adult case ($2600 x 150,000 cases annually = $390 million in losttime). These estimates do not include business losses in the restaurant ortourist industries related to outbreaks of the disease.
Source: PR Newswire