د. وجدان اكرم                                                                        HEPATITIS
Hepatitis C is an infection caused by a virus that attacks the liver and leads to inflammation. Most people infected with the hepatitis C virus (HCV) have no symptoms. In fact, most people don't know they have the hepatitis C infection until liver damage shows up, decades later, during routine medical tests. 
Hepatitis C is one of several hepatitis viruses and is generally considered to be among the most serious of these viruses. Hepatitis C is passed through contact with contaminated blood — most commonly through needles shared during illegal drug use.
Hept.C; is of low endemicity with prevalence rate of carriers of about 0.5% in blood donors and normal population.
Estimated number of carriers is about
 100 000.
Chronic carrier state of  the disease might occur in more than 70% of the patients, with all possible chronic sequel like chronic active hepatitis, liver cirrhosis and hepatocellular carcinoma.

Reservoir:
Humans, virus has been transmitted experimentally to chimpanzees.
Period of communicability:
From one or more weeks before the onset of first symptoms.
Susceptibility: is general.

Chronic Hepatitis C 
Factors Promoting Progression or Severity 
Increased alcohol intake
Age > 40 years at time of infection
HIV co-infection
Other
–	Male gender
–	Chronic HBV co-infection
Perinatal Transmission of HCV
•	Transmission only from women HCV-RNA positive at delivery
–	Average rate of infection 6%
–	Higher (17%) if woman co-infected with HIV
–	Role of viral titer unclear
•	No association with
–	Delivery method
–	Breastfeeding
•	Infected infants do well
–	Severe hepatitis is rare

HCV Prevention and Control

Reduce or Eliminate Risks for 
Acquiring HCV Infection
•	Screen and test donors
•	Virus inactivation of plasma-derived products
•	Risk-reduction counseling and services
–	Obtain history of high-risk drug and sex behaviors
–	Provide information on minimizing risky behavior, including referral to other services
–	Vaccinate against hepatitis A and/or hepatitis B
•	Safe injection and infection control practices
Preventing HCV Transmission to Others
•	Do not donate blood, body organs, other tissue.
•	Do not share items that might have blood on them
–	personal care (e.g., razor, toothbrush)
–	home therapy (e.g., needles)
•	Cover cuts and sores on the skin
Other Transmission Issues
•	HCV not spread by kissing, hugging, sneezing, coughing, food or water, sharing eating utensils or drinking glasses, or casual contact
•	Do not exclude from work, school, play, child-care or other settings based on HCV infection status
•	What is hepatitis B?
Hepatitis B is a serious public health problem that affects people of all ages  Hepatitis B is caused by a highly infectious virus that attacks the liver and can lead to severe illness, liver damage, and in some cases, death.
•	The best way to be protected from hepatitis B is to be vaccinated with hepatitis B vaccine, a vaccine used for more than two decades and proven safe and effective 

Who is at risk for HBV infection?
*have a job that exposes you to human blood 
*share a household with someone who has lifelong HBV infection 
*inject drugs 
*have sex with a person infected with HBV 
*have sex with more than one partner during a six-month period 

*received blood transfusions in the past before excellent blood testing was available (1975) 

*have hemophilia 

*are a patient or worker in an institution for the developmentally disabled 
*travel internationally to areas with a high prevalence of hepatitis B

How is HBV spread?
*HBV is found in blood and certain body fluids—such as serum, semen, vaginal  secretions and saliva —of people infected with HBV. 
*HBV is not found in sweat, tears, urine, or respiratory secretions. Contact with even small amounts of infected blood can cause infection.

*re-chewing food for babies or sharing chewing gum 
*using unspecialized needles in ear or body piercing, tattooing, or acupuncture 
*using the same immunization needle on more than one person

Hepatitis B virus IS NOT spread by:
*casual contact like holding hands 
*eating food prepared by an infected person 
*kissing or hugging 
*sharing silverware, plates, or cups 
*visiting an infected person's home 
*sneezing or coughing
Do people usually recover from HBV infection?
Nearly 95% of adults recover after several months. They clear the infection from their bodies and become immune. 
Unfortunately, of those who become newly infected with HBV, about 5% of adults and up to 90% of children under age 5 are unable to clear the infection from their bodies; they become chronically infected. 
*HBsAg : Detection of acutely or chronically infected people, Ag used in Hepatitis B vaccine 
* Anti-HBs: Identification of people who have resolved infection ,immunity after immunization .
* HBeAg : Identification of people at increased risk of transmitting HBV.
Anti-HBe: Identification of people with lower risk of transmitting.
Anti-HBc: Identification of people with acute ,resolved or chronic HBV infection 
*No test is available for HBcAg .

Epidemiology:
occurrence: world wide, endemic with little seasonal variation.
WHO estimates that more than 2 billion persons have been infected with HBV ( including 350 million chronically infected ). Each year about 600000-1 million persons die as a result of HBV infections and over 4 million new acute clinical cases occur  

*In countries highly endemic with HBV, (HBsAg prevalance 8% or higher ) most infection occur during infancy and early childhood.
*Where HBV endemicity is intermediate (HBsAg prevalence from 2%- 7% ) infection occur in all age group.
*Where the endemicity is low (HBsAg prevalence under 2%) most infection occurs in young adult especialy those belonging to known risk group.                                                                              
Reservoir: human , chimpanzees are susceptible, but an animal reservoir in nature has not been recognized. 
HBVis stable on environmental surfaces for at least 7 days 
Incubation period:
usually 45-180 days ,average 60-90 days .As short as 2 weeks and rarely as long as 6-9 month , this depends on: 
1- amount of virus inoculum .
2, mode of transmission.
3. host factors. .
Period of communicability:
all persons who are HBsAg positive are .
potentially infectious. 
Susceptibility: is general . Disease is often milder and anicteric in children, in infants is usually asymptomatic. Protective immunity follows infection if Ab develop to HBsAg ( anti HBs). And HBsAg is negative 
 
Strategy for prevention 
•	Immunization of infants, children, adults at increased risk of infection .
•	Prevention of perinatal transmission by routine screening of all pregnant women
•	Routine immunization of infant.
•	Routine immunization of adolescents who previously have not immunized .
Hepatitis B immunoprophylaxis
Hepatitis B immunoglobulin provides short term protection ( 3-6) months & is indicated in post exposure circumstances .
Hepatitis B vaccine is used for pre and post exposure protection & provide long term protection.
Hepatitis B vaccine 
*Highly effective and save vaccine
* Is administered I.M.in the anterio lateral thigh or deltoid area, depending on the age and size of recipient .
*Administration in the buttocks or intradermally =decrease immunogenicity 
* 90-95 efficacy for preventing HBV infection & clinical HB among susceptible children and adults.  
*Immune memory remain intact for 15 years or more & protects against clinical acute & chronic HBV infection
* Booster doses are not recommended .
* Pregnancy& lactation is not contraindication to immunization