Epidemiology of Viral Hepatitis Ashry Gad Mohamed Prof. of Epidemiology Consultant Medical Epidemiologist

Hepatitis A Abrupt onset. Fever Malaise Anorexia Abdominal discomfort Jaundice

More than 90% are asymptomatic Seroprevalence increases with age. At age 15, 95% are seropositive. Case fatality rate (CFR)= 0.3%. If age > 40 years CFR=2%. Studies in KSA: % % Taif 10-82% Jazan (1-12 years)

Agent: RNA virus Reservior : Human (Clinical & subclinical cases) Incubation period: days ( median one month).

Period of communicability : Last two weeks of I.P. + one week of illness. Modes of transmission: Fecal-oral route. Common source outbreaks. Blood transfusion (rare).

Prevention and Control Good sanitation & personal hygiene. “Careful hand washing” Day- Care centers Hand washing after every diaper change and before eating. Shellfish heat 85-90C 4 minutes. steam 90 seconds.

Inactivated hepatitis A vaccine months. Protection after one month. Lasting immunity at least 10 years. Hepatitis A patient: Enteric precaution for the PC

Hepatitis B Incidous onset. Anorexia. Abdominal discomfort. Nausia. Vomiting. Arthralgia. Jaundice.

Carriage rates: Sudan 13-19% Pakistan 10-16% Egypt % Saudi Arabia 8.5% Jordan Syria 4-6% Iraq 4-5% Morocco 3-6% Yemen 5-6%

2 billion people infected 360 million CHB More than 500,000 death/year

OVERALL PREVALENCE OF HBsAg AMONG SAUDIS IN THE 80’S ACCORDING TO REGIONS Positivity (%) Al-Faleh. Annals of Saudi Medicine, 1988

COMPARISON OF PREVALENCE OF HBsAg AMONG SAUDI CHILDREN IN 1989 (n=4575) AND 1997 (n=5355) – ACCORDING TO AGE Al Faleh, J Infect 1999

PREVALENCE OF HBsAg POSITIVITY AMONG BLOOD DONORS IN KKUH FROM 1987 TO 2000 Positivity (%)

Natural History Gow, BMJ 2001

Agent: Double strand DNA. Serotypes adw, ayw, adr, ayr. Reservior: Human (case + carrier). I.P. 2-3 months. P.C. One week of I.P. + illness period + carriage. Carriage depends on age.

Modes of transmission: Percutaneous and permucosal exposure to infective body fluids. Blood transfusion. Organs transplants. Sharing needles. Haemodialysis. Needlestick. Tattooing. Razors & toothbrushes.

Sexual transmission. Perinatal transmission.

Prevention and control Wide scale immunization of infants. Immunization of high risk persons. Haemodialysis patients. Bleeding disorders. Susceptible households. Health care personnels. Blood banks: avoid donors from risky groups.

Education & history taking. Testing for HBs Ag. Discourage: Tattooing, Drug abuse, Extramarital sexual relations. Needle stick Single dose of HBIG (24 hours). Vaccine series.

Sexual exposure Single dose of HBIG (14 days). Vaccination. Infants to HBsAg +ve mothers. 0.5 ml HBIG im. First dose of the vaccine. 2 nd & 3 rd doses at 1 & 6 months later. Health care personnel. Universal precautions

Hepatitis C

USA 4 M USA 4 M SOUTH AMERICA 10 M SOUTH AMERICA 10 M AFRICA 32 M AFRICA 32 M EASTERN MEDITERRANEAN 20M EASTERN MEDITERRANEAN 20M SOUTH EAST ASIA 30 M SOUTH EAST ASIA 30 M AUSTRALIA 0.2 M AUSTRALIA 0.2 M WHO, 1999 WESTERN EUROPE 9 M WESTERN EUROPE 9 M FAR EAST/ASIA 60 M FAR EAST/ASIA 60 M 170 Million Hepatitis C virus (HCV) carriers 3-4 MM new cases / year 170 Million Hepatitis C virus (HCV) carriers 3-4 MM new cases / year

AGE SPECIFIC PREVALENCE OF ANTIBODY TO HCV/ANTI-HCV AMONG HEALTHY SAUDIS Age Group (years) Community Based Study No. testedAnti-HCV Pos. (%) Location 1 – ,9 Central Province Eastern Province North-Western Province South-Western Province Southern Province 10 – (1.2)Gizan 20 – (1.1)Gizan (2.1)Gizan 40 – (3.3)Gizan > (3.5)Gizan Total (1.8)Gizan Al-Faleh et al, Hepatology Vol. 14(2), 1991

COMPARISON OF PREVALENCE OF ANTI-HCV IN SAUDI CHILDREN BETWEEN THE STUDIES CARRIED OUT IN 1989 AND 1997

PREVALENCE OF ANTIBODY TO HCV TO SAUDI HIGH RISK GROUPS High Risk GroupNo. Tested No. Pos. %Location Hemophiliacs KKUH, Riyadh Thalassaemia and sickle cell disease KKUH, Riyadh  -thalassaemia major KKUH, Riyadh* Sickle cell anaemia KKUH, Riyadh* Patients with sexually transmitted diseases KKUH, Riyadh* 2 nd -generation anti-HCV tests and confirmation were only done in this study.

ANTI-HCV IN HAEMODYLYSIS PATIENTS IN SAUDI POPULATION AuthorNo. of PersonsType of Test% Fakunle et al895ELISA I53.7 Al-Mugeriren et al20 ChildrenELISA I45.0 Ayoola et al74ELISA I41.9 Huraib et al22 HD Centre 1147 Persons ELISA II68.8

11( 6 major) with many subtypes and quasispecies The predominate genotype in Saudi is Genotype 4 (62.9% ) Europe & America Genotype 1  75 (24.8) %  severe disease Genotype 2 = 10.8 (7.4) % Genotype 3 = 5.8 (5.9) % Genotype 1 & 4  Poor response to therapy Hepatitis C Virus Genotypes

Natural History of HCV Infection Exposure (Acute phase) ResolvedChronic CirrhosisStable SlowlyProgressive HCC Transplant Death 20% (17) 15% (15)85% (85) 25% (4) 80% (68) 75% (13) HIV and Alcohol Alcohol MJ Semin Liver Dis 1995; 15: Management of Hepatitis C NIH Consensus Statement 1997; March 24-26:15(3).

Blood transfusio n IV drug abuse Important HCV Transmission Modes 1:100,000 in US 80% infected in first year

Vertical transmission mother - Child Uncommon HCV Transmission Modes Household transmission 1-5% ? Needle stick injury 3%

Features of Hepatitis C Virus Infection Incubation periodAverage 6-7 weeks Range 2-26 weeks Range 2-26 weeks Acute illness (jaundice)Mild (<20%) Case fatality rateLow Chronic infection60%-85% Chronic hepatitis10%-70% Cirrhosis<5%-20% Mortality from CLD1%-5% Age- related

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

Serologic Pattern of Acute HCV Infection with Progression to Chronic Infection Symptoms +/- Time after Exposure Titer anti- HCV ALT Normal Years Months HCV RNA

Exposures Known to Be Associated With HCV Infection in the United States Injecting drug use Transfusion, transplant from infected donor Occupational exposure to blood –Mostly needle sticks Iatrogenic (unsafe injections) Birth to HCV-infected mother Sex with infected partner –Multiple sex partners

Injecting Drug Use and HCV Transmission Highly efficient –Contamination of drug paraphernalia, not just needles and syringes Rapidly acquired after initiation –30% prevalence after 3 years –>50% after 5 years Four times more common than HIV

Occupational Transmission of HCV Average incidence 1.8% following needle stick from HCV-positive source –Associated with hollow-bore needles Prevalence 1-2% among health care workers –Lower than adults in the general population –10 times lower than for HBV infection

HCV Related to Health Care Procedures Recognized primarily in context of outbreaks –Chronic hemodialysis –Hospital inpatient setting –Private practice setting –Home therapy Unsafe injection practices –Reuse of syringes and needles –Contaminated multiple dose medication vials

HCW to Patient Transmission of HCV Rare –In U.S., none related to performing invasive procedures Most appear related to HCW substance abuse –Reuse of needles or sharing narcotics used for self-injection No restrictions routinely recommended for HCV-infected HCWs

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

Sexual Transmission of HCV Case-control, cross sectional studies –Infected partner, multiple partners, early sex, non- use of condoms, other STDs, sex with trauma, Partner studies –Low prevalence (1.5%) among long-term partners infections might be due to common percutaneous exposures (e.g., drug use), BUT –Male to female transmission more efficient more indicative of sexual transmission

Household Transmission of HCV Rare but not absent Could occur through percutaneous/mucosal exposures to blood –Contaminated equipment used for home therapies IV therapy, injections –Theoretically through sharing of contaminated personal articles (razors, toothbrushes)

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

Reduce Risks for Disease Progression and Further Transmission Identify persons at risk for HCV and test to determine infection status –Routinely identify at risk persons through history, record review Provide HCV-positive persons –Medical evaluation and management –Counseling Prevent further liver damage Prevent transmission to others MMWR 1998;47 (No. RR-19)

HCV Prevalence by Selected Groups United States Hemophilia Injecting drug users Surgeons, PSWs Hemodialysis Average Percent Anti-HCV Positive Gen population adults Military personnel STD clients Pregnant women

HCV Testing Routinely Recommended Ever injected illegal drugs Received clotting factors made before 1987 Received blood/organs before July 1992 Ever on chronic hemodialysis Evidence of liver disease Healthcare, emergency, public safety workers after needle stick/mucosal exposures to HCV- positive blood Children born to HCV-positive women Based on increased risk for infection Based on need for exposure management

Postexposure Management for HCV IG, antivirals not recommended for prophylaxis Follow-up after needlesticks, sharps, or mucosal exposures to HCV-positive blood –Test source for anti-HCV –Test worker if source anti-HCV positive Anti-HCV and ALT at baseline and 4-6 months later For earlier diagnosis, HCV RNA at 4-6 weeks –Confirm all anti-HCV results with RIBA Refer infected worker to specialist for medical evaluation and management

Hepatitis E - Clinical Features Incubation period:Average 40 days Range days Case-fatality rate:Overall, 1%-3% Pregnant women, 15%-25% Illness severity:Increased with age Chronic sequelae:None identified

Most outbreaks associated with fecally contaminated drinking water Minimal person-to-person transmission Hepatitis E - Epidemiologic Features Hepatitis E - Epidemiologic Features

Geographic Distribution of Hepatitis E Outbreaks or Confirmed Infection in >25% of Sporadic Non-ABC Hepatitis