Card Set Information
what is hepatitis?
inflammation of the liver
which hepatitis virus is the most commonly occuring viral hepatitis?
what are the modes of transmission for HAV?
what is the incubation period for HAV?
when is HAV the most communicable?
2-3 weeks before the onset of jaundice (preicteric)
how are the signs and symptoms defined?
defined by jaundice
what is the icteric phase of HAV and who does it appear in?
jaundice is present
mostly adults rare in children
what is the preicteric phase and what are its symptoms?
abrupt onset of flu-like symptoms (long and severe)
liver is enlarged and tender to palpation
what is the anicteric phase?
absence of jaundice
2-3 times more prevalent than icteric
often misdiagnosed because it resembles the flu
how can you get HAV immunity?
AntiHAV in serum 2-3 weeks after onset
how can you prevent the transmission of HAV?
cooking food- 185 degree will inactivate virus
sanitation- public health
how do you prevent HAV in the dental setting?
who are the risk groups for HAV that should be vaccinated?
Travelers to places with high HAV
chronic liver disease
children living in places with high rate of HAV
what hepatitis virus has had an increased incidence in the past 20 years?
what fluids carry infectious HBV?
what are the modes of transmission for HBV?
what is a risk population?
those that have an increased prevalence of infection, increase chances or likelihood of infection and increased prevalence of disease carriers
who are the individuals at high risk for HBV?
infants-born to HIV infected mothers
IV drug users
Mental institutions-pt and staff
hemodialysis-pt and staff
recipients of blood products
health care presonnel-low risk if following ppe
contact with HBV carriers
military populations in countries with high endemic
returning travelers who stayed more than 3 months or were treated
morticians and embalmers
immigrants and refugees
sexual contact- multiple partners
what is the incubation period for HBV?
average of 60-90 days
what indicates the communicability of HBV and when is it no longer detectible in blood?
presence of HBsAG indicates communicability, found in blood as early as 30 days postexposure
after jaundice no longer detectible in blood.
what is the transient subclinical infection of HBV?
no icteric stage
transient infection-rapid strong immune response
what is the disease process of acute type B HBV?
onset is slower than other hep viruses
cannot be distinguished on basis of clinical signs and symptoms
period of illness is longer than hep A
what are the symptoms of acute type b HBV?
rash itching and joint pains
what percentages of children and infants become carriers of HBV?
5-10% infected after age five
30% infected between ages 1-5
90% infected at birth
How is immunity of HBV obtained other than vaccine?
presence of anti-HB's in serum-had an exposure
unknown presence-subclinical HBV
what are three ways to prevent HBV?
transmission in infancy and childhood-immunoprophylaxis
enforce blood bank control measures
enforce sterilization/disposable syringes and needles
what are the two types of active HBV immunizations?
how is plasma derived vaccines for active immunization of HBV prepared?
prepared by using purified and formalin-treated HBsAg from plasm of chronic HBsAg carrier, it inactivates viruses
how is recombinant DNA vaccine for active immunization of HBV prepared?
synthesis HBsAg in culture of yeast, it is purified and sterilized
what is the effectiveness for HBV vaccines?
20-39 years 95% effective
children 99% effective
what is the most common chronic blood-borne infection in the US?
what was hepatitis C originally called?
hep non A, non B
how is HCV transmitted?
percutaneous-blood, needles, syringes, transfusions
nonpercutaneous-sexual transmission, perinatl exposure
what is the disease process for HCV?
onset-no clinical symptoms or abdominal pain, nausea, vomiting and jaundice
acute infection-chronic infection
chronic liver disease
what are the risk factors of having HCV?
severe liver disease
what are the principle risk factors of transmitting HCV?
blood transfusion before 1991
IV drug us
intranasal cocaine user
tattooing, ear/body piercing
what are the prevention and control methods for HCV?
strict standard procedures
same measures for hep B
what is Hep D coinfection with?
HBV-cannot cause infection except in the presence of HBV
how is hep D transmitted?
multiple exposures to HBV
blood and body fluids
what are the characteristics of hep D
more severe than hep B alone
higher mortality rate
abrupt onset, signs and symptoms resemble HBV
what are the three parts of the disease process?
what is coinfection?
acute HDV occurring with acute HBV may lead to resolution of both types. If HBV is cleared HDV is cleared
what is superinfection?
acute HDV is superimposed on an existing carrier of HBV. HBV unchanged but delta state develops
what is superimposition?
chronic delta hepatitis superimposes on the chronic HBsAg carrier
what is the prevention of Hep D?
same as hep B
immunization for hep B protects against hep D
what is hep E similar to?
how is hep E transmitted?
person-person thru oral-fecal route
who is affected more with hep E?
adults affected more than children
what affect does hep E have on pregnant women?
high mortality rate
how can we prevent and control hep E?
sanitary disposal of waste