Transcript hepatitis virus

Learning Your “A B C s”
THE HEPATITIS VIRUSES
JAY E S H A . PAT E L , M D , D T M & H
Conflicts of Interest
 No financial or other conflicts of interest for this talk.
Hepatitis causing Viruses
 Acute hepatitis may occur as part of the clinical
course of a number of viral infections, including
Human Cytomegalovirus, Epstein-Barr virus, Herpes
Simplex Virus, Yellow Fever Virus and Rubella.
 The term "hepatitis virus" is usually used to describe
infections caused by agents whose primary tissue
tropism is the liver. At least five hepatitis viruses
have been recognized and these have been named,
hepatitis A, B, C, D and E.
Clinical Features
 Hepatitis due to all these viruses presents clinically in a
very similar fashion, especially during the acute phase.
Thus, a specific diagnosis can only be made in the
laboratory.
 The majority of infections are often asymptomatic or
produce only mild non-specific symptoms.
 Common clinical features include: anorexia, nausea,
vomiting, right upper quadrant pain and raised liver
enzymes AST and ALT. Jaundice is the hall mark of
infection, but tends to develop late. Anicteric cases are
also very common.
Hepatitis A
 Family: Picornaviridae
Structure: small; 27 nm in diameter, nonenveloped spherical particle
Hepatitis A: Key Facts
 Hepatitis A can cause mild to severe illness.
 Globally, there are an estimated 1.4 million cases of
hepatitis A every year.
 The hepatitis A virus is transmitted through ingestion of
contaminated food and water, or through direct contact
with an infectious person.
 Hepatitis A is associated with a lack of safe water and poor
sanitation.
Hepatitis A: Key Facts
 Epidemics can be explosive in growth and cause
significant economic losses.
 Improved sanitation and the hepatitis A vaccine are
the most effective ways to combat the disease.
 Hepatitis A rates in the United States have declined by
95% since Hepatitis A vaccine first became available in
1995. In 2010, 1,670 acute symptomatic cases of
Hepatitis A were reported. After adjusting for
asymptomatic infection and underreporting, the
estimated number of new infections was 17,000
Hepatitis A: Clinical Features
 Incubation period 2-7 weeks (mean 28 days)
 Symptoms of hepatitis A range from mild to severe,
and can include fever, malaise, loss of appetite,
diarrhea, nausea, abdominal discomfort, darkcolored urine and jaundice
 Pre-icteric phase lasting about 5 days.
 The subsequent icteric phase resolves within 3
months in 85% of cases.
Hepatitis A: Clinical Features
 Convalescence may be prolonged, and fatigue and
alcohol intolerance can last up to 18 months. There is no
chronic form of the disease.
 Milder disease than Hepatitis B; asymptomatic infections
are very common, especially in children. Adults,
especially pregnant women, may develop more severe
disease.
 Fulminant hepatitis: rare; 0.3-1.8 % of cases
Highest risk: pregnant women, elderly, pre-existing liver
disease, other chronic medical conditions
Hepatitis A: Pathogenesis
 Virus enters via the gut; replicates in the alimentary
tract and spreads to infect the liver, where it
multiplies in hepatocytes. Viremia is transient. Virus
is excreted in the stools for two weeks preceding the
onset of symptoms.
Hepatitis A: Epidemiology
Hepatitis A: Diagnosis
 Virus cannot be cultured in vitro from clinical
material; diagnosis depends on:
Serology HAV-specific IgM
What does the Hepatitis A test result mean?
If you have not been given the hepatitis vaccine, results of
hepatitis testing indicates the following:
HAV IgM
Total HAV Antibody (IgM Results Indicate
and IgG)
Positive
---
Acute HAV infection
Negative
Positive
No active infection, but
previous HAV exposure;
has developed immunity to
HAV
Negetive
Positive
Has been exposed to HAV
but does not rule out acute
infection
negetive
Negative
No current or previous
HAV infection; vaccine
may be recommended if at
risk
Hepatitis A
Hepatitis A Treatment
 There is no specific treatment for hepatitis A.
Therapy is aimed at maintaining comfort and
adequate nutritional balance, including replacement
of fluids that are lost from vomiting and diarrhea.
Hepatitis A: Prevention
 Hygiene: Food hygiene, Hand hygiene
 Active Immunization
Inactivated cell culture derived vaccine is available; it is
recommended for travelers to developing countries and,
indeed, all adults who are not immune. It is the recommended
form of post-exposure prophylaxis if the exposure is identified
early, and if there are no predisposing risk factors for severe
disease. If there are such risk factors, or if prophylaxis is
delayed, passive immunization in addition to vaccination is
recommended.
 Passive immunisation
Normal immunoglobulin (antibody prepared from pooled
human serum) given to close contacts of acute cases.
Protection is short lived: three months
Hepatitis A Vaccines
 Havrix and Vaqta, Twinrix
 Hepatitis A vaccination is recommended for all children older
than age 1.
 People who work or travel in areas where hepatitis A is common
should be vaccinated. These areas include Africa, Asia (except
Japan), the Mediterranean, Eastern Europe, the Middle East,
Central and South America, Mexico, and parts of the Caribbean.
 If you are traveling to these areas before you are fully immunized
(fewer than 4 weeks after your first shot), you should get a
preventive dose of immunoglobulin (IG). If you are just a shortterm traveler to these areas, you may wish to receive
immunoglobulin (IG) instead of the vaccine.
Hepatitis A Vaccine
 Other people who are at higher risk for hepatitis A
include:








People who use recreational, injectable drugs
People who work with the hepatitis A virus in a laboratory or
with primates that may be infected with the virus
People who have chronic liver disease
People who receive clotting factor concentrate to treat
hemophilia or other clotting disorders
Military personnel
Men who have sex with other men
Employees of child day care centers
People who care for patients living in long-term nursing
homes and other facilities
Hepatitis A Vaccines
Post-exposure Prophylaxis: Hepatitis A
 Persons who have recently been exposed to HAV and who have not been




vaccinated previously should be administered a single dose of Hepatitis A vaccine
or IG (0.02 mL/kg) as soon as possible, within 2 weeks after exposure. The
guidelines vary by age and health status:
For healthy persons aged 12 months–40 years, Hepatitis A vaccine at the ageappropriate dose is preferred to IG because of the vaccine’s advantages, including
long-term protection and ease of administration, as well as the equivalent
efficacy of vaccine to IG.
For persons aged 40 years and older, IG is preferred because of the absence of
information regarding vaccine performance in this age group and because of the
more severe manifestations of Hepatitis A in older adults. The magnitude of the
risk of HAV transmission from the exposure should be considered in decisions to
use vaccine or IG in this age group.
Vaccine can be used if IG cannot be obtained.
IG should be used for children aged less than12 months, immunocompromised
persons, persons with chronic liver disease, and persons who are allergic to the
vaccine
Which groups do NOT need routine vaccination
against Hepatitis A?
 Food service workers. Consideration may be given to vaccination




of employees who work in areas where community-wide outbreaks
are occurring and where state and local health authorities or private
employers determine that such vaccination is cost-effective.
Health care workers. If a patient with Hepatitis A is admitted to
the hospital, routine infection-control precautions will prevent
transmission to hospital staff.
Children under 12 months of age. Because of the limited
experience with Hepatitis A vaccination among children in this age
group, the vaccine is not currently licensed for children age <12
months.
Child care center attendees. The frequency of outbreaks of
Hepatitis A is not high enough in this setting to warrant routine
Hepatitis A vaccination of staff
Residents of institutions for developmentally disabled
persons. The occurrence of HAV infection has diminished, and
routine vaccination against Hepatitis A is no longer recommended for
this population.
Who requires protection (i.e., IG or Hepatitis A
vaccine) after exposure to HAV?
 Close personal contacts. Close personal
contacts of persons with serologically confirmed
Hepatitis A (i.e., through a blood test), including:
Household and sex contacts
 Persons who have shared illicit drugs with someone
with Hepatitis A
 Consideration should also be given for other types of
ongoing, close personal contact with a person with
Hepatitis A (e.g., a regular babysitter or caretaker).

Who requires protection (i.e., IG or Hepatitis A
vaccine) AFTER exposure to HAV?
 Child-care center staff, attendees, and attendees'
household members
 PEP should be administered to all previously unvaccinated staff
and attendees of child care centers or homes if 1) one or more cases
of Hepatitis A are recognized in children or employees or 2) cases
are recognized in two or more households of center attendees.
 In centers that provide care only to older children who no longer
wear diapers, PEP need be administered only to classroom contacts
of the index patient (i.e., not to children or staff in other
classrooms).
 When an outbreak occurs (i.e., Hepatitis A cases in three or more
families), PEP should also be considered for members of
households that have diaper-wearing children attending the center.
If a case of Hepatitis A is found in a school, hospital, or
office setting, what should be done?
 If a single case of Hepatitis A is identified in a school
(other than a child care setting in which children wear
diapers), office, or other work setting, and if the source of
infection is outside the school or work setting, PEP (i.e.,
injection of IG or Hepatitis A vaccine) is not routinely
recommended. Similarly, when a person who has
Hepatitis A is admitted to a hospital, staff should not
routinely be administered PEP; instead, careful hygienic
practices should be emphasized.
 However, if it is determined that Hepatitis A has been
spread among students in a school or among patients and
staff in a hospital, PEP should be administered to
unvaccinated persons who have had close contact with an
infected person.
Hepatitis B: Key Facts
 Hepatitis B is a viral infection that can cause both acute
and chronic disease.
 The virus is transmitted through contact with the blood
or other body fluids of an infected person.
 About 240 million people are living with chronic hepatitis
B and 600 000 people die every year due to the
consequences of hepatitis B.(USA 1 mil./4000)
 Hepatitis B is an important occupational hazard for
health workers.
 Hepatitis B is preventable with the currently available
safe and effective vaccines.
Hepatitis B: Epidemiology
 In highly endemic areas, HBV is most commonly spread from mother to
child at birth, or from person to person in early childhood.
 Perinatal or early childhood transmission may also account for more than
one third of chronic infections in areas of low endemicity, although in
those settings, sexual transmission and the use of contaminated needles,
especially among injecting drug users, are the major routes of infection.
 The hepatitis B virus can survive outside the body for at least seven days.
During this time, the virus can still cause infection if it enters the body of a
person who is not protected by the vaccine.
 The hepatitis B virus is not spread by contaminated food or water, and
cannot be spread casually in the workplace.
 The incubation period of the hepatitis B virus is 75 days on average, but
can vary from 30 to 180 days. The virus may be detected 30 to 60 days
after infection and persists for variable periods of time.
Hepatitis B Prevalence
Hepatitis B Serology
 Hepatitis B surface antigen (HBsAg): A protein on
the surface of HBV; it can be detected in high levels in
serum during acute or chronic HBV infection. The
presence of HBsAg indicates that the person is infectious.
The body normally produces antibodies to HBsAg as part
of the normal immune response to infection. HBsAg is the
antigen used to make Hepatitis B vaccine.
 Hepatitis B surface antibody (anti-HBs): The
presence of anti-HBs is generally interpreted as indicating
recovery and immunity from HBV infection. Anti-HBs also
develops in a person who has been successfully vaccinated
against Hepatitis B.
Hepatitis B Serology
 IgM antibody to Hepatitis B core antigen
(IgM anti-HBc): Positivity indicates recent
infection with HBV (≤6 months). Its presence
indicates acute infection.
 Total Hepatitis B core antibody (anti-
HBc): Appears at the onset of symptoms in acute
Hepatitis B and persists for life. The presence of
anti-HBc indicates previous or ongoing infection
with HBV in an undefined time frame.
Hepatitis B Serology
 Hepatitis B e antigen (HBeAg): A secreted product
of the nucleocapsid gene of HBV that is found in serum
during acute and chronic Hepatitis B. Its presence
indicates that the virus is replicating and the infected
person has high levels of HBV.
 Hepatitis B e antibody (HBeAb or anti-
HBe): Produced by the immune system temporarily
during acute HBV infection or consistently during or
after a burst in viral replication. Spontaneous
conversion from e antigen to e antibody (a change
known as seroconversion) is a predictor of long-term
clearance of HBV in patients undergoing antiviral
therapy and indicates lower levels of HBV.
Hepatitis B Serology Interpretation
-
Tests
Results
Interpretation
HBsAg
anti-HBc
anti-HBs
negative
negative
negative
Susceptible
HBsAg
anti-HBc
anti-HBs
negative
positive
positive
Immune due to natural infection
HBsAg
anti-HBc
anti-HBs
negative
negative
positive
Immune due to Hepatitis B vaccination
HBsAg
anti-HBc
IgM anti-HBc
anti-HBs
positive
positive
positive
negative
Acutely infected
HBsAg
anti-HBc
IgM anti-HBc
anti-HBs
positive
positive
negative
negative
Chronically infected
HBsAg
anti-HBc
anti-HBs
negative
positive
negative
1.Interpretation unclear; four possibilities: Resolved infection (most common)
2.False-positive anti-HBc, thus susceptible
3."Low level" chronic infection
4.4. Resolving acute infection
Hepatitis B serology
 How long does it take for blood to test HBsAg-
positive after exposure to HBV?
 HBsAg will be detected in an infected person’s
blood an average of 4 weeks (range: 1–9 weeks)
after exposure to the virus. About 1 of 2 patients
will no longer be infectious by 7 weeks after onset
of symptoms, and all patients who do not remain
chronically infected will be HBsAg-negative by 15
weeks after onset of symptoms
Who should be vaccinated against Hepatitis B?
 All infants, beginning at birth
 All children aged <19 years who have not been vaccinated






previously
Susceptible sex partners of Hepatitis B surface antigen
(HBsAg)-positive persons
Sexually active persons who are not in a long-term,
mutually monogamous relationship (e.g., >1 sex partner
during the previous 6 months)
Persons seeking evaluation or treatment for a sexually
transmitted disease
Men who have sex with men
Injection drug users
Susceptible household contacts of HBsAg-positive persons
Who should be vaccinated against Hepatitis B?
 Health care and public safety workers at risk for exposure to blood







or blood-contaminated body fluids
Persons with end-stage renal disease, including predialysis,
hemodialysis, peritoneal dialysis, and home dialysis patients
Residents and staff of facilities for developmentally disabled
persons
Travelers to areas with high Hepatitis B endemicity
Persons with chronic liver disease
Persons with HIV infection
Unvaccinated adults with diabetes mellitus who are aged 19
through 59 years (discretion of clinicians for unvaccinated adults
with diabetes mellitus who are aged ≥60 years)
All other persons seeking protection from HBV infection
What are the Hepatitis B vaccines licensed in the
United States?
Single-antigen Hepatitis B vaccines
ENGERIX-B®
RECOMBIVAX HB®
Combination vaccines
COMVAX®: Combined Hepatitis B-Haemophilus influenzae type b (Hib)
conjugate vaccine. Cannot be administered before age 6 weeks or after age
71 months.
PEDIARIX®: Combined Hepatitis B, diphtheria, tetanus, acellular
pertussis (DTaP), and inactivated poliovirus (IPV) vaccine. Cannot be
administered before age 6 weeks or after age 7 years.
TWINRIX®: Combined Hepatitis A and Hepatitis B vaccine. recommended
for persons aged ≥18 years who are at increased risk for both Hepatitis A
virus and HBV infections.
• Can a patient receive the first dose of Hepatitis B vaccine
from one manufacturer and subsequent doses from
another manufacturer?
Yes. No differences in immune response are observed when vaccines
from different manufacturers are used to complete the vaccine series.
• If there is an interruption between doses of Hepatitis B
vaccine, does the vaccine series need to be restarted?
No, the series does not need to be restarted. If the vaccine series was
interrupted after the first dose, the second dose should be
administered as soon as possible. The second and third doses should
be separated by an interval of at least 8 weeks. If only the third dose
is delayed, it should be administered as soon as possible.
• Is it harmful to administer an extra dose(s) of Hepatitis A
or Hepatitis B vaccine or to repeat the entire vaccine series
if documentation of vaccination history is unavailable?
No. If necessary, administering extra doses of Hepatitis A or
Hepatitis B vaccine is not harmful.
Who should receive postvaccination testing?
• Testing for immunity is advised only for persons whose
subsequent clinical management depends on knowledge of
their immune status, including
• Infants born to HBsAg-positive mothers
• Health care workers and public safety workers at high risk
for continued percutaneous or mucosal exposure to blood
or body fluids
• Chronic hemodialysis patients, HIV-infected persons, and
other immunocompromised persons (e.g., hematopoietic
stem-cell transplant recipients or persons receiving
chemotherapy)
• Sex partners of persons with chronic HBV infection
Are booster doses of Hepatitis B vaccine
recommended?
• Booster doses are recommended only in certain circumstances:
• For hemodialysis patients, the need for booster doses should be
assessed by annual testing for antibody to Hepatitis B surface antigen
(anti-HBs). A booster dose should be administered when anti-HBs
levels decline to <10 mIU/mL.
• For other immunocompromised persons (e.g., HIV-infected
persons, hematopoietic stem-cell transplant recipients, and persons
receiving chemotherapy), the need for booster doses has not been
determined. When anti-HBs levels decline to <10 mIU/mL, annual
anti-HBs testing and booster doses should be considered for those
with an ongoing risk for exposure.
For persons with normal immune status who have been
vaccinated, booster doses are not recommended.
Approved Hepatitis B Drugs
 Interferon Alpha (Intron A) is given by injection several times a week
for six months to a year, or sometimes longer. Can cause side effects such
as flu-like symptoms (mainly fever, headache, chills, myalgia, and fatigue).
Injection site reaction. Rash, alopecia, anemia, neutropenia. Psychiatric
side effects have included depression (up to 40%), anxiety (up to 9%), and
nervousness (up to 3%). Abnormal dreaming, aggravated depression,
aggressive reaction, apathy, emotional lability, feeling of ebriety, manic
depression, manic reaction, personality disorder, psychosis, suicidal
ideation, and suicide attempt have been reported in less than 5% of
patients. Frontal subcortical dementia and choreic movements mimicking
Huntington's disease have been reported. Homicidal ideation and
psychosis including hallucinations have been reported.
 Pegylated Interferon (Pegasys) is given by injection once a week
usually for six months to a year. Same side effects as Interferon alpha but
less often, less sever.
Approved Hepatitis B Drugs
 Lamivudine (Epivir-HBV, Zeffix, or Heptodin) for at least one year or
longer. Can cause headache, nausea, malaise, fatigue, nasal signs and
symptoms, diarrhea, cough, lactic acidosis.
 Adefovir Dipivoxil (Hepsera) for at least one year or longer. Can cause
asthenia, headache, abdominal pain, nausea, flatulence, diarrhea, dyspepsia,
elevated creatinine, hematuria, hypophosphatemia.
 Entecavir (Baraclude) for at least one year or longer. Can cause headache,
fatigue, dizziness, and nausea.
 Telbivudine (Tyzeka, Sebivo) for at least one year or longer. Can cause
chills, fever, diarrhea, runny nose, cough, lactic acidosis.
 Tenofovir (Viread) is a pill taken once a day, for at least one year or
longer. Can cause rash, diarrhea, headache, body pain, depression, asthenia,
and nausea.
Hepatitis C
 Hepatitis C virus (HCV) infection is the most
common chronic bloodborne infection in the United
States; approximately 3.2 million persons are
chronically infected.
 It can range in severity from a mild illness lasting a
few weeks to a serious, lifelong illness.
Hepatitis C
 Sixty to 70% of persons newly infected with HCV typically
are usually asymptomatic or have a mild clinical illness.
 HCV RNA can be detected in blood within 1–3 weeks after
exposure.
 The average time from exposure to antibody to HCV (anti-
HCV) seroconversion is 8–9 weeks, and anti-HCV can be
detected in >97% of persons by 6 months after exposure.
 Chronic HCV infection develops in 70%–85% of HCV-
infected persons; 60%–70% of chronically infected persons
have evidence of active liver disease.
 The majority of infected persons might not be aware of
their infection because they are not clinically ill.
Hepatitis C
 HCV is most efficiently transmitted through percutaneous
exposure to infected blood (e.g., through transfusion of
blood from unscreened donors or through use of injecting
drugs).
 Although much less frequent, occupational, perinatal,
and sexual exposures also can result in transmission of
HCV.
 Can HCV be spread within a household?
Yes, but this does not occur very often. If HCV is spread
within a household, it is most likely a result of direct,
through-the-skin exposure to the blood of an infected
household member.
Hepatitis C
• What is the risk of acquiring HCV infection from transfused blood or
blood products in the United States?
Now that more advanced screening tests for HCV are used in blood banks, the risk
is considered to be less than 1 chance per 2 million units transfused. Before 1992,
when blood screening for HCV became available, blood transfusion was a leading
means of HCV transmission.
• Can HCV be spread during medical or dental procedures?
As long as Standard Precautions and other infection control practices are used
consistently, medical and dental procedures performed in the United States
generally do not pose a risk for the spread of HCV. However, HCV has been spread
in health care settings when injection equipment, such as syringes, was shared
between patients or when injectable medications or intravenous solutions were
mishandled and became contaminated with blood. Health care personnel should
understand and adhere to Standard Precautions, which includes safe injection
practices and other guidance aimed at reducing bloodborne pathogen risks for
patients and health care personnel.
Hepatitis C
 What percentage of persons infected with
HCV develop symptoms of acute illness?
 Approximately 20%–30% of those newly infected
with HCV experience fatigue, abdominal pain, poor
appetite, or jaundice.
 How soon after exposure to HCV do
symptoms appear?
 In those persons who do develop symptoms, the
average time period from exposure to symptom
onset is 4–12 weeks (range: 2–24 weeks).
Hepatitis C and Health Care Personnel
• What is the risk for HCV infection from a needlestick exposure
to HCV-contaminated blood?
After a needlestick or sharps exposure to HCV-positive blood, the risk of
HCV infection is approximately 1.8%.
• Other than needlesticks, do other exposures, such as splashes
to the eye, pose a risk to health care personnel for HCV
transmission?
Although a few cases of HCV transmission via blood splash to the eye have
been reported, the risk for such transmission is expected to be very low.
Avoiding occupational exposure to blood is the primary way to prevent
transmission of bloodborne illnesses among health care personnel.
Depending on the medical procedure involved, Standard Precautions may
include the appropriate use of personal protective equipment (e.g., gloves,
masks, and protective eyewear).
What blood tests are used to detect HCV
infection?
• Screening tests for antibody to HCV (anti-HCV)
enzyme immunoassay (EIA)
enhanced chemiluminescence immunoassay (CIA)
• Recombinant immunoblot assay (RIBA)
• 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)
Drugs for Hepatitis C treatment
 Peginterferon
 Ribavirin
 Telaprevir( Incivek):protease inhibitor, effective for
Genotype 1. Side effects: rash, itching, diarrhea,
anemia, anal pruritus.
 Boceprevir (Victerelis): protease inhibitor, for
Genotype 1. Side effects: fatigue, anemia ,nausea,
diarrhea, taste disturbance
Hepatitis D/delta
 It can propagate only in the presence of the hepatitis B
virus (HBV).[1] Transmission of HDV can occur either via
simultaneous infection with HBV (coinfection) or
superimposed on chronic hepatitis B or hepatitis B carrier
state (superinfection).
 Both superinfection and coinfection with HDV results in
more severe complications compared to infection with HBV
alone. These complications include a greater likelihood of
experiencing liver failure in acute infections and a rapid
progression to liver cirrhosis, with an increased chance of
developing liver cancer in chronic infections.[2] In
combination with hepatitis B virus, hepatitis D has the
highest mortality rate of all the hepatitis infections, at 20%.
Hepatitis D/delta
 Distribution: more common in Russia, Mediterranean,
Africa, S. America. Uncommon in China.
 Transmitted same as hepatitis B.
 Prevention: prevent hepatitis B
 Diagnosis: Hepatitis delta antigen and antibody.
 Treatment: Peginterferon may have benefit. Liver
transplantation in fulminant and end stage hepatitis.
Hepatitis E
 Hepatitis E is a liver
disease caused by the
hepatitis E virus: a nonenveloped, positivesense, single-stranded
ribonucleic acid (RNA)
virus.
Hepatitis E: Pathogenesis
 Acute hepatitis E is similar to hepatitis A; virus
replicates in the gut initially, before invading the
liver and virus is shed in the stool prior to the onset
of symptoms. Viraemia is transient. A large
innoculum of virus is needed to establish infection.
Hepatitis E: Epidemiology
 Every year there are 20 million hepatitis E infections and
57 000 hepatitis E-related deaths.
 Prevalence of infection is low in first world countries. Large
outbreaks have been described in India, Mexico and North
Africa where the source of infection is usually gross fecal
contamination of drinking water supplies, which is the main
source of infection.
 Case-to-case transmission to household contacts appears to
be uncommon.
 Various animal species such as the domestic pig have been
identified as reservoirs of the virus and outbreaks of human
infections have been recorded associated with the
consumption of inadequately cooked meat.
Hepatitis E Prevalence
E
Hepatitis E: Diagnosis
 Diagnosis of hepatitis E infection is usually based on
the detection of specific antibodies to the virus in the
blood.
 Additional diagnostic tests require specialized
laboratory facilities and are used only in research
studies. These are:


PCR to detect the hepatitis E virus RNA
Immune electron microscopy to detect the hepatitis E virus.
 Hepatitis E should be suspected in outbreaks of
waterborne hepatitis occurring in developing countries,
especially if the disease is more severe in pregnant
women, or if hepatitis A has been excluded.
Hepatitis E Time Course
Hepatitis E: Prevention
 Maintaining quality standards for public water supplies
 Establishing proper disposal systems to eliminate
sanitary waste.
 On an individual level, infection risk can be reduced
by:



Maintaining hygienic practices such as hand washing with safe
water, particularly before handling food
Avoiding drinking water and/or ice of unknown purity
Avoiding eating uncooked shellfish, and uncooked fruits or
vegetables that are not peeled or that are prepared by people living
in or travelling in highly endemic countries.
 In 2011, the first vaccine to prevent hepatitis E
infection was registered in China. Although it is not
available globally, it could potentially become available
in a number of other countries.