Introduction- Viral Hepatitis may be defined as infection of the liver caused by any of half dozen viruses. Twenty years ago hepatitis A virus (HAV) and hepatitis B virus (HBV) were the only known aetiological agents of viral hepatitis. Today, in addition to HAV and HBV hepatitis viruses C,D,E and G have also been identified and are recognized as etiological agents of viral hepatitis.
TYPES OF HEPATITIS :-Its 5th types.
1. hepatitis a
2. hepatitis b
3. hepatitis c
4. hepatitis d
5. hepatitis e
Hepatitis A :-Prevention and containment :-
1. Control of Reservoir :- Control of reservoir is difficult because of the following factors :
(a) Faucal shedding of the virus is at its height during the incubation period and early phase of illness.
(b) The occurrence of large number of sub-clinical cases.
(c) Absence of specific treatment.
(d) Low socio-economic profile of the population usually involved.
2. Control of Transmission :- The best means of reducing the spread of infection is by promoting simple measures of personal and community hygiene e.g., hand-washing after eating and after toilet ; the sanitary disposal of excreta which will prevent contamination of water , food and milk ; and purification of community water supplies by flocculation, filtration and adequate chlorination. Studies indicated that 1mg/L of free residual chlorine can cause destruction of the virus in 30 minutes at PH values of 8.5 or less. Other control measures include proper autoclaving of syringes, needles and other equipment. If all these measures are properly implemented, a substantial reduction of HAV infection can be expected.
3.Control of Susceptible Population :-Human Immunoglobulin : A well established procedure is the use of normal human immunoglobulin prepared from pooled plasma of healthy donors (gamma globulin) to induce passive immunity. It is recommended for
(a) Susceptible persons traveling to highly endemic areas.
(b) Close personal contacts of persons with HAV, and
(c) for the control of outbreaks in institutions.
Several inactivated or live attenuated vaccines against hepatitis A have been developed, but only 4 inactivated hepatitis A vaccines are currently available internationally. All 4 vaccines are similar in terms of efficacy and side effect profile. The vaccines are given parenterally, as a 2 – dose series, 6 to 18 months apart. The dose of vaccine, vaccination schedule, age for which the vaccine is licensed, varies from manufacturer to manufacturer. No vaccine is licensed for children aged less than one year. A combination vaccine containing inactivated hepatitis A and recombinant hepatitis B.
vaccines has been licensed since 1996 for use in children aged 1 year or older in several countries. The combination vaccine is given as a 3 – dose series, using a 0, 1, 6 months schedule.
Hepatitis B:- Since there is no specific treatment, prevention has been the major aim in managing viral hepatitis B. The following measures are available.
PLASMA DERIVED VACCINE:- This is based on the surface antigen (HBsAg) which is harvested and purified from the plasma of human carriers of hepatitis B virus. The final vaccine is a formalin inactivated sub-unit viral vaccine for intramuscular injection. Each 1 ml dose of the vaccine contains 20 micrograms of hepatitis surface antigen formulated in an alum adjuvant.
Interferon is the only drug that has been found effective in the treatment of HCV infection. However, treatment is very expensive – thousands of dollars for the drug alone – and must be administered by injection several times a week for several months. Moreover, some patients, experience serious side effects. Also, about half of the patients go into remission, but 50 % relapse when the treatment is stopped ; only 25 % have long term remission. Given its cost, only a minority of patients can afford it, or are likely to be offered. Studies involving less costly, orally administered drugs are continuing, but results so far have been disappointing. For a number of technical reasons, the development of a vaccine to prevent HCV infection is unlikely for many years.
Hepatitis D :-
Hepatitis D, also known as the Hepatitis Delta Virus, is an infection that causes the liver to become inflamed. This swelling can impair liver function and cause long-term liver problems, including liver scarring and cancer.
Hepatitis D is spread when blood or other body fluids from a person infected with the virus enters the body of someone who is not infected. Hepatitis D can be an acute, short-term infection or become a long-term, chronic infection.
• Yellow skin and eyes (jaundice)
• Stomach upset.
• Pain in your belly.
• Throwing up.
• Not feeling hungry.
• Joint pain.
• Dark urine.
There is no vaccine to prevent hepatitis D. However, prevention of hepatitis B with hepatitis B vaccine also protects against future hepatitis D infection. Hepatitis D Serology Training – CDC offers an online training that covers the serology of hepatitis D and other types of viral hepatitis.
There are no known treatments for acute or chronic hepatitis D. Unlike other forms of hepatitis, current antiviral medications don’t seem to be very effective in treating HDV. You may be given large doses of a medication called interferon for up to 12 months.
Hepatitis E :-
Hepatitis E is a liver disease caused by infection with a virus known as hepatitis E virus (HEV). Every year, there are an estimated 20 million HEV infections worldwide, leading to an estimated 3.3 million symptomatic cases of hepatitis E.
The hepatitis E virus is transmitted mainly through the fecal-oral route due to fecal contamination of drinking water. This route accounts for a very large proportion of clinical cases with this disease.
Treatment :- Hepatitis E usually resolves on its own without treatment. There is no specific antiviral therapy for acute hepatitis E.
Mr. Durgesh Prajapat, II Sem., B Pharma, School of Pharmacy, Career Point University, Kota