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Hepatitis A Virus The first descriptions of hepatitis (epidemic jaundice) are generally attributed to Hippocrates (460 -370 BC)
Hepatitis A Virus • In the 1970 s, identification of the virus • Most commonly reported type of hepatitis in the United States • Humans only natural host
Resistance of HAV Stable to: Acid at p. H 3 Solvents(ether, chloroform) Detergents Salt water, groundwater(months) Drying(stable) Temperature: -20°C for years 4℃: weeks 56℃ for 30 minutes: stable 61℃ for 20 minutes: partial inactivation Hepatology, 2006, 43(2 Suppl 1): S 164– 172.
Resistance of HAV Inactivated by: Chlorine treatment of drinking water Sodium hypochlorite “Eau de Javel”(1: 100 dilution ) K Permanganate 30 mgL , 5 min Formalin [formaldehyde](0. 35%, 37℃, 72 hours) Acetic acid(2%, 4 hours) B-propiolactone (0. 25%, 1 hours)[inactivating reagent to viral vaccines] Ultraviolet radiation(2μW/㎝ 2/min) Hepatology, 2006, 43(2 Suppl 1): S 164– 172.
Hepatitis A Virus Transmission • Close personal contact (e. g. , household contact, sex contact, child day care centers) • Contaminated food, water (e. g. , infected food handlers, raw shellfish) • Blood exposure (rare) (e. g. , injecting drug use, transfusion)
Concentration of Hepatitis A Virus in Various Body Fluid Feces Serum Saliva Urine 100 102 104 106 108 Infectious Doses per ml Source: Viral Hepatitis and Liver Disease 1984; 9 -22 J Infect Dis 1989; 160: 887 -890 1010
Hepatitis A Transmission • Virus particles are present in the stool • Fecal-oral route via contaminated food or water • Saliva contact, sexual contact, and arthropods also have been implicated
HAV contagiousity • The peak infectivity occurs during the two weeks before the onset of jaundice or elevation of liver enzyme levels when the concentration of virus in the stool is highest. • When jaundice appears, the viral concentration in the stool declines and most patients are noninfectious after one week Lancet 1998; 351: 1643 -1649 Epidemiol Rev 2006; 28: 101 -111
Hepatitis A Virus Infection Typical Serologic Course Symptoms Total anti-HAV Titer ALT Fecal HAV 0 1 Ig. M anti-HAV 2 3 4 5 6 Months after Exposure 1 2 2 4
Preventing Hepatitis A • • Hygiene Sanitation Hepatitis A vaccine Immune Globulin
HEPATITIS A PREVENTION • virus can live on the fingers for up to four hours. • Hand hygiene — Hand washing is an essential and effective way to prevent the spread of infection. Hands should ideally be wet with water and plain or antimicrobial soap, and rubbed together for 15 to 30 seconds. • It is not clear if alcohol-based hand rubs are effective against hepatitis A virus. For this reason, food handlers, day care providers, travelers, and anyone else who is at risk of transmitting or becoming infected with HAV is advised to wash their hands with soap and water when possible.
HEPATITIS A PREVENTION • Alcohol-based hand rubs are a reasonable alternative if a sink is not available. • Hands should be cleaned after changing a diaper or touching any soiled item. • They should also be washed before and after preparing food and eating, after going to the bathroom, and after handling garbage or dirty laundry.
Hepatitis A Vaccines
Hepatitis A Prevention Immune Globulin
Clinical Management • Antibiotics are of no value in the treatment of HAV infection • Antiviral agents, as well as corticosteroids, have no effect in the management • Medical therapy can only be supportive • Adequate nutritional balance • No specific dietary recommendations other than avoiding alcohol or any other hepatotoxic substances (Acetaminophene) • Patients should rest in bed as needed Fields Virology. 3 rd ed. Philadelphia: Lippincott - Raven; 1996: 735 -782. Infectious Diseases. 5 th ed. Philadelphia: Lippincott Co; 1994: 790 - 797.
Questions frequently asked by hepatitis patient concerning diet and nutrition • What foods are good for the liver • Are there foods that can harm the liver • How much protein should I get in my diet
Diet in Acute Hepatitis • Patients with acute hepatitis are usually adequately nourished before the illness. • Acute hepatitis is usually a mild disease, associated with only a few days of anorexia, nausea, and occasionally vomiting. These are usually well tolerated by the patients, who require no nutritional supplementation, and are encouraged to eat normally. • Usually they can take some food by mouth and enough fluids to prevent dehydration.
• Most people with liver disease find that eating multiple small meals throughout the day is the best approach, as it maximizes energy levels and the ability to digest and absorb food • However, if one insists on eating three meals per day try to follow the saying “ eat breakfast like a king, lunch like prince and dinner like a pauper”
Diet in Acute Hepatitis • Old literature emphasized lipid restriction. This, however, is not true, and lipid restriction has no role in acute hepatitis unless fats aggravate nausea in an individual patient. • Dietary restrictions have no place in the management of mild or moderate acute hepatitis.
Diet in Acute Hepatitis • Nutritional supplementation and iv fluids and nutrients are reserved for the patients with excessive nausea and vomiting who cannot maintain a sufficient fluid balance. • Alcohol should be avoided in acute hepatitis and for the 6 months following recovery
Diet in Acute Hepatitis • Patients usually need 30 -35 kcal/kg/day. • Excess calories should be avoided, particularly as carbohydrates, as this promotes hepatic lipogenesis, liver dysfunction, and increase CO 2 production and the work of breathing. • Carbohydrates should be sufficient to maintain normal blood glucose levels, and should not exceed insulin reserves. They should supply 60 -70% of non nitrogen calories.
Diet in Acute Hepatitis • Lipid restriction has no scientific basis in patients with acute hepatitis • Fat helps make food tastier. This is important for people who suffer from a suppressed appetite • Around 30% of total calorie intake should be supplied as fat • Low-fat foods
Diet in Acute Hepatitis • Proteins should not be restricted in patients with acute hepatitis • Protein intake should be in the range of 1 -1. 5 g/kg/day. • Proteins should not be restricted in patients with liver disease unless they become protein intolerant due to encephalopath.
Caffeine’s Effect on Hepatitis • Caffeine is present in coffee, tea, chocolate, cola • Caffeine is metabolized through the liver • However, caffeine it self is not directly harmful to the liver • Avoidance of excessive caffeine
Coclusion • Hepatitis A virus infection is preventable with several strategies • Hand washing with soap & water is one of the most effective strategies • No antibiotics or other medicines will shorten the course of infectious hepatitis • Patients should rest in bed as needed • Follow a healthy diet