hepatits b & c

HEPATITISPresented by/ Hams Hamed

outlineDefinition of hepatitisCauses of hepatitisTypes of hepatitis virusesHepatitis B virusHepatitis C virus

Definition of hepatitis:

Hepatitis is an inflammation of the liver, the condition can be self-limiting or can progress to fibrosis (scarring), cirrhosis or liver cancer.

CAUSES OF HEPATITIS

NON- VIRAL

Giant cell

hepatitisIschemic hepatitis

Non-alcoholic fatty liver hepatitis

Autoimmune hepatitis

Toxic and drug

induced hepatitis

Alcoholic hepatitis

VIRAL

A, B, C, D, E

HEPATITIS B & C VIRUSES

ROUTE OF TRANSMISSION

RISK OF TRANSMISSION:Risk of transmission mainly depend on:

Environmental Viability (ability to survive outside the

human body)

Frequency of the disease occurring

in population

Viral loadNumber of viruses in

patient’s blood

DIRECT INFECTIONthrough a cut on the skin (percutaneous), as a result of:An accidental bite by the

patient during a dental procedure.

Needle wound during an anesthetic procedure.

Cut with a sharp object such as a scalpel blade.

INDIRECT INFECTIONAerosols of saliva.Gingival fluid.Natural organic particles

(dental caries tissue) mixed with air and water.

e.g. blood splash to the eye.

HOW DENTISTS GET THE INFECTION?

SIGNS AND SYMPTOMS

HBV

HEPATITIS B VIRUS

HEPATITIS B VIRUS

Prevalence:

The world can be divided into three areas where the prevalence of chronic HBV infection is:

High (>8%), Intermediate (2-8%), and Low (<2%).

Egypt is of intermediate endemicity (2–8%), nearly 2-3 million Egyptians are chronic carriers.

HEPATITIS B VIRUS

Incubation period:

Symptoms begin an average of 90 days (range: 60–150 days) after exposure to HBV.

Diagnosis: (serology)

Detection of hepatitis B virus infection involve serum or blood tests that detect either viral antigens (proteins produced by the virus) or antibodies produced by the host.

HEPATITIS B VIRUSDiagnosis: (serology)

• indicating infectious person.• Used to make hepatitis B vaccine.(HBsAg)

• Indicating recovery and immunity.• In successfully vaccinated person.

(anti-HBs)

• Indicating replicating virus.• Person has high level of HBV.(HbeAg)

HEPATITIS B VIRUSTreatment: Acute hepatitis B infection does not usually require

treatment as most adults clear the infection spontaneously.

Treatment of chronic infection may be necessary to reduce the risk of cirrhosis and liver cancer.

Treatment lasts six months to year depending on medication and genotype.

Antiviral drugs lamivudine (Epivir), adefovir (Hepsera).

HEPATITIS B VIRUSVaccination:

Vaccine by 3 injections : 1st dose at base line, 2nd dose after one month, 3rd dose after 6 months from 1st and post vaccination (anti-HBs) antibody level one month later if:

>100 IU/l ---Responder (85%-90% of individual)10-100--- poor responder (need booster)<10 ---non responder (repeat vaccination)

HCV

HEPATITIS C VIRUS

Source of infection for persons of hepatitis C

HEPATITIS C VIRUS

Prevalence:

About 170 million people are living with HCV infection.

the prevalence is reported to be the highest (approximately 10%) in Egypt.

HEPATITIS C VIRUS

Incubation period:

The incubation period for hepatitis C virus is (2 weeks to 6 months).

The average time period from exposure to symptom onset is 4–12 weeks

(range: 2–24 weeks).

HEPATITIS C VIRUS

Diagnosis:

Several blood tests are performed to test for HCV infection, including:Screening tests for antibody to HCV (anti-HCV)

Qualitative tests to detect presence or absence of virus (HCV RNA polymerase chain reaction [PCR])

Quantitative tests to detect amount (titer) of virus (HCV RNA PCR)

HEPATITIS C VIRUSTreatment:Therapy based on interferon and ribavirin, which required weekly

injections for 48 weeks, cured approximately half of treated patients, but caused frequent and sometimes life-threatening adverse reactions.

Recently, new antiviral drugs have been developed.These medicines, called direct antiviral agents (DAA) are much more

effective, safer and better-tolerated than the older therapies. Therapy with DAAs result can cure most persons with HCV infection

and treatment is shorter (usually 12 weeks) and safer.

HEPATITIS C VIRUS

vaccination:There is no vaccine against HCV.There are major challenges to the future development of a

hepatitis C vaccine.

Refrences:http://www.cdc.gov/hepatitis/hcv/index.htmhttps://en.wikipedia.org/wiki/Hepatitishttp://www.healthline.com/health/hepatitis#Diagnosis5http://

www.dentalcare.com/media/en-US/education/ce307/ce307.pdfhttp://

www.ejgd.org/article.asp?issn=2278-9626;year=2013;volume=2;issue=1;spage=13;epage=19;aulast=Setia