Viral Hepatitis
HBcAg
A core protein antigen of hepatitis B virus present inside the nuclei of hepatic cells indicating previous or ongoing hepatitis B infection. Continues to be high following resolution of the infection and in chronically infected individuals
Hepatitis A Vaccination
Administered to individuals at increased risk: Those traveling to intermediate and high HAV-endemic countries (administered 3 weeks before travel to allow time for body to develop antibodies) Disabled or geriatric populations who reside in a nursing home or assisted living facility who have not previously received the vaccine Individuals with a compromised immune system, such as those with HIV
Tips for National Board
All forms of hepatitis that are bloodborne begin with a consonant (B, C, D, G). This is easy to remember because "bloodborne" begins with a consonant. Those that are oral-fecal begin with a vowel (A, E). This is easy to remember because "oral" begins with a vowel.
New cases of HBV
An estimated 19,800 new infections in 2013 and an estimated 1.2 million people with chronic HBV infection. (reported by CDC) This number has declined since 1992 because the administration of routine vaccinations was implemented in late 1991. Newborns now receive the first of 3 intramuscular vaccinations prior to leaving the hospital. In addition, in 1995, the CDC made the recommendation that all 12 year olds not previously vaccinated receive the HBV vaccination. CDC statistics estimate there are almost a million HBV carriers in the United States. Unfortunately, many people do not even know they are infected so strict infection control protocols are essential As the author of your text states, a millimeter of blood from an infected person may contain as many as 100 million virus particles meaning that only small amounts of blood or body fluids are necessary to transmit the disease to others. Children, the elder population and immunocompromised individuals being most susceptible.
HAV Immunity
Anti-HAV (antibodies) are usually detectable in the serum within 2 weeks of exposure Immunity to re-infection follows with recovery Passive immunity: immunoglobulin is used for the prevention or modification of HAV in a person known to be susceptible or who has been accidentally exposed (made from inactivated HAV to stimulate the body's immune system to develop antibodies)
Anti-HBsAg
Anti-HBsAg in the serum means the person had a previous exposure to hepatitis B and/or received the immunization and developed antibodies for HBsAg. If a previous exposure to HBV, the person may be carrying virus without knowing it because they may have been one of the 30% that developed no signs/ symptoms
HGV Prevention
Avoid blood-borne infection No vaccine No specific treatment
Now a "Recommended" Childhood Vaccination HAV
Became a recommended vaccination in 2000 Administered in two doses First dose given between 12- 23 months of age Second dose given 6-18 months later
Routes of Transmission HBV
Body fluids including Tears Saliva Semen Urine Sweat Vaginal Secretions Nasopharyngeal secretions
Effectiveness of Vaccines HBV
Both act in a comparable manner to stimulate antibodies and same degree of immunity 20 to 39 years - over 95% immunity Titer testing is recommended 2-3 months after last injection to verify seroconversion (presence of anti-HBsAg antibodies) Lower responses in smokers, the elderly, hemodialysis patients, and obese individuals No effect on a carrier Not contraindicated during pregnancy and would be recommended for a woman in a high-risk group
HEV
Clinical course and distribution mimics HAV Incubation period is 2 to 9 weeks Communicable period while infected Mortality rate in pregnant women 15%-25%
Jaundice
Condition in which there are bile pigments in the blood and deposition of bile pigments in the skin Skin takes on a yellowish appearance
Anti-HBs
Development of anti-HBs indicates past infection and immunity Approximately, 90% of those infected have complete recovery without developing a carrier state Approximately 2-10% of those infected become carriers. If an individual tests HBsAg positive on 2 different occasions when tested 2 months apart -or- being HBsAg positive and IgM anti-HBc negative at a single test. Anyone who is positive for HBsAg has potential to dpread the disease and unfortunately, carriers are usually asymptomatic so the disease goes undetected
HAV Transmission
Fecal-oral Transmission: the virus is excreted in stools two (2) weeks preceding the onset of symptoms. This is why it is so critical that hands be washed after using the restroom and/or when changing diapers Waterborne or food-borne: epidemics may occur when sanitation is inadequate; contaminated water may carry HAV directly to those using the water, and shellfish living in the water may become contaminated
HBV Immunization
First available in 1981 Two types: a ) Heptavax B vaccine (plasma derived from HBsAg from hepatitis B carriers) b) Recombivax DNA HB vaccine (a synthetically developed vaccine)
Hepatitis G Virus (HGV)
First recognized in 1996 Considered a distant relative to HCV Transmission of HGV through blood, blood products, and/or body fluids Little is known about the frequency of HGV infection, the nature of the illness, or how to prevent it.
Hepatitis E Virus (HEV)
Formerly known as enterically transmitted non-A, non-B hepatitis Hepatitis E is rare in the United States Carried into this country from under developed countries especially those with poor sanitary conditions Transmitted through contaminated water and fecal oral transmission just like HAV
Administration of Vaccination HBV
Given in three (3) doses: Initial dose, a second dose1 month later, and a third dose 6 months after the 2nd dose Injected into the deltoid muscle for adults and children; injected into the thigh muscle for infants Lowered response if given at the wrong site
National Board Questions
HBsAg = hepatitis B surface antigen (on the surface) HBcAg = hepatitis B core antigen (inside the virus) HBeAg = hepatitis B e antigen (inside the virus) (HB = hepatitis; and Ag = antigen)
HGV
HGV has been identified in between 1-2% of blood donors in the United States. Can only be identified through expensive and sophisticated lab testing Transfused blood containing HGV has caused some cases of Hepatitis. Patients with hemophilia and other bleeding conditions who require large amounts of blood or blood products are at risk of Hepatitis G.
Treatment of HAV
HVA can be treated. If you have been exposed you should be treated with the immunoglobulin within the first few days to prevent signs & symptoms. Occasionally chronic hepatitis develops but 85-90% of patients recover completely. There is no carrier state with HAV
Facts about HAV
Hepatitis A still occurs in the United States, although not as frequently as it once did. Over the last 20 years, there has been more than a 90% decrease in Hepatitis A cases. Many experts believe this decline is a result of the vaccination of infants and toddlers as well as people at risk for Hepatitis A" New cases are now estimated to be around 20,000 each year.
Hepatitis B Virus (HBV)
Hepatitis B is an enveloped DNA virus, while all of the rest of the hepatitis viruses are RNA viruses. (This is often a question on the national boards and another piece of trivia that should be stored in your memory bank).
Species Specific
Hepatitis B is passed through the transfer of serum from one human to another; and can not be passed from an animal to a human. Hepatitis B does not discriminate, it can occur at any age. However, statistics show the highest incidence in the US is in individuals between the ages of 20-40, most often sexually transmitted.
Disease Process
Hepatitis D is more severe and the mortality rate is greater than with HBV. Onset is abrupt and signs and symptoms resemble that of HBV. Receiving the Hepatitis B vaccine also provides protection for the delta virus.
HBeAg
Hepatitis e antigen also found inside the virus correlates with HBV replication during acute infection usually disappearing afterward but sometimes persisting in chronic disease Individuals testing positive for HBeAg indicates high communicability
HAV Incubation and Communicability
Incubation period is 15-40 days, with the average of 28-30 days. Although jaundice does not appear for 2-3 weeks, the virus is still communicable during this time frame. Therefore, one should not rely on jaundice as a means of infectivitiy. Communicability begins to diminish shortly after jaundice appears Seen more frequently in children and young adults who have not been vaccinated. More severe when occurs in adulthood.
Pathogenesis of Hepatitis B
Infected blood or serum through parenteral inoculation (entry into the body other than through the digestive tract) Contaminated dental or medical instruments Accidental self-inoculation by health care worker via a needlestick or accidental puncture with a sharp instrument Drug abusers sharing needles Blood transfusions before 1985
Peri-natal Transmission HBV
Most chronic Hepatitis B infected individuals were infected at birth or during early childhood. Preventive measures are possible when a pregnant woman tests positive for hepatitis B. There is a high incidence of Hepatitis B in Japan/Asia; and mothers are passing the virus to their babies at birth and the boys become hepatitis B "carriers".
Is a Booster Necessary? hbv
Not at this time But anti-HBs levels should be checked annually for high risk populations (those requiring hemodialysis, receiving chemotherapy, HIV+, etc) If antibody levels fall below 10m IU/ml than a booster is recommended
Hepatitis C Virus (HCV
Originally called non A, non B hepatitis Initially associated with blood transfusions. However now a serologic test for antibody HCV is done on blood donors Most common type of hepatitis seen and an estimated 3.2 million people in the U.S. with chronic HCV infection. AN estimated 29.700 new infections in 2013. (as reported by the CDC)
HCV Transmission
Percutaneous exposure to contaminated blood and plasma derivatives Contaminated needles; accidental needlesticks Transfusions Saliva Sexual transmission Perinatal exposure "The transmission of Hepatitis C Virus can occur via improper handling and cleaning of dental instruments.
What if Individual Does Not Seroconvert?
Physician will administer another series of 3 vaccinations and then order another titer test If individual does not convert after the second series, physician will conduct some additional testing because the inability to produce anti -HBsAg antibodies may be a sign that the person is a hepatitis B carrier or has a chronic HBV infection.
Phases of HAV
Preicteric Phase: abrupt onset of flu-like illness with fever, headache, fatigue, nausea, vomiting, and abdominal pain. Liver may be enlarged and tender to palpation Icteric Phase: jaundice appears; patient may be ill for a few days to a month
HEV prevention
Sanitary disposal of wastes Proper Hand washing No vaccine available IG (immunoglobulin) prepared from plasma collected in non-HEV-endemic areas is not effective in preventing clinical disease during HEV outbreaks and the efficacy of IG prepared from plasma collected in HEV-endemic areas is unclear.
HBV Symptoms
Similar to HAV but slower onset and longer duration Can include the following .......... Fever Fatigue Jaundice Joint Pain Rash Dark Urine Grey-colored stools Loss of Appetite Nausea & Vomiting Abdominal pain
New Drugs
Since 2013, new drugs have been utilized that are showing greater than a 90% success rate These drugs are very expensive and cost is a factor since it is estimated that a 12 week regimen is about $96,000 Patient compliance is also a factor
Causes and SymptomsHGV
Some researchers believe that there may be a group of G viruses, rather than just one. Others remain doubtful that HGV actually causes illness. If it does, the type of acute or chronic (long-lasting) illness that results is not clear. When diagnosed, acute HGV infection has usually been mild and brief.
HBsAg
Surface antigen is present in the serum of those infected with hepatitis B. Anyone who tests positive for HBsAg has a potential to spread the disease Testing for HBsAg is used in diagnosis of hepatitis B HBIg can be injected to trigger the immune system to develop antibodies after an accidental needlestick/puncture
HBV can result in ...how long can it live on A dry surface
That can result in ......... chronic hepatitis cirrhosis of the liver liver cancer death Note: Can live on a dry surface for 9-14 days
Hepatitis D Virus (HDV)
The delta hepatitis virus cannot cause infection except in the presence of HBV infection. Is a "concurrent infection" which means you must have B for the D virus to grow, if you treat B you get rid of D. Some think of Hepatitis D as a complication of Hepatitis B. Hepatitis D is primarily seen in persons who have had multiple exposures to HBV.
Incubation Period HBV
The incubation period is longer for Hepatitis B, and ranges from 6 weeks to 5-6 months. (the average time is 2-3 months) Unfortunately, 30% of those infected do not know they are carrying the virus because they have such vague symptoms that can be contributed to something else. Another 30% develop easily recognizable symptoms while approximately 30% do not develop any symptoms! So again many people have no idea they are transmitting the disease.
HCV Symptoms
The onset of Hepatitis C is slow and insidious (more dangerous that it appears to be) because 80% of those infected have no clinical signs or symptoms Other symptoms include nausea, vomiting and/or abdominal discomfort Can progress to jaundice More than 70% of those exposed will develop serious liver disease. Chronic liver disease (more common than HBV) With Hepatitis B although you are much sicker in the acute stages you get sick, get better, and you're done with it! Carrier state is possible No vaccination at this time but in progress
Hepatitis A Virus (HAV)
The virus is carried through contaminated water, food, and shellfish. Avoid drinking local water or drinks that are made with crushed ice in some parts of the world. Consume bottled water with an unbroken seal. Unwashed raw fruits and vegetables can also be a concern. Consider getting the HAV vaccination before traveling to a third world country.
HDV Transmission
Transmission similar to HBV Direct exposure to contaminated blood and serous body fluids Contaminated needles and syringes IV drug abusers Sexual contact Perinatal transfer
Viral Hep
Viruses cause a variety of types of hepatitis, a disease causing an inflammation of the liver. Hepatitis B, C, D, G are bloodborne diseases transmitted by direct or indirect contact with infected body fluids. Hepatitis B and C are the biggest concerns for the dental health team. Hepatitis A & E, transmitted via contaminated food and water are of little concern in the dental office.