Hepatitis A

Contents

What is Hepatitis A

What is Hepatitis A

Hepatitis A is a vaccine-preventable, communicable disease of the liver caused by the hepatitis A virus (HAV) ¹⁾. Hepatitis A is usually transmitted person-to-person through the fecal-oral route or consumption of contaminated food or water. Hepatitis is an inflammation of the liver. Hepatitis A is a self-limited disease that does not result in chronic infection. Most adults with hepatitis A have symptoms, including fatigue, low appetite, stomach pain, nausea, and jaundice, that usually resolve within 2 months of infection; most children less than 6 years of age do not have symptoms or have an unrecognized infection. Antibodies produced in response to hepatitis A infection last for life and protect against reinfection. The best way to prevent hepatitis A infection is to get vaccinated.

Hepatitis A, is caused by the hepatitis A virus (HAV). The disease spreads through contact with an infected person’s stool. You can get it from:

Eating food made by an infected person who did not wash their hands after using the bathroom
Drinking untreated water or eating food washed in untreated water
Putting into your mouth a finger or object that came into contact with an infected person’s stool
Having close contact with an infected person, such as through sex or caring for someone who is ill.

In rare cases, hepatitis A can cause a sudden loss of liver function, especially in older adults or people with chronic liver diseases. Acute liver failure requires a stay in the hospital for monitoring and treatment. Some people with acute liver failure may need a liver transplant.

How common is hepatitis A virus infection in the United States ?

Hepatitis A rates in the United States have declined by more than 95% since hepatitis A vaccine first became available in 1995. National Notifiable Diseases Surveillance System (NNDSS) at ²⁾

In 2015, a total of 1,390 cases of hepatitis A were reported to Centers for Disease Prevention and Control (CDC) from 50 states, a 12.2% increase from the number of reported cases in 2014. However, the overall incidence rate in 2015 was 0.4 cases per 100,000 population, the same as 2014. After adjusting for under-ascertainment and under-reporting, an estimated 2,800 hepatitis A cases occurred in 2015. More information on hepatitis A surveillance is available at https://www.cdc.gov/hepatitis/statistics/2015surveillance/index.htm

Figure 1. Hepatitis A incidence rate 1984-2015

How is Hepatitis A Transmitted

Hepatitis A is caused by hepatitis A virus that infects liver cells and causes inflammation. The inflammation can affect how your liver works and cause other signs and symptoms of hepatitis A.

The virus most commonly spreads when you eat or drink something contaminated with fecal matter, even just tiny amounts. It does not spread through sneezing or coughing.

Person-to-person transmission through the fecal-oral route (i.e., ingestion of something that has been contaminated with the feces of an infected person) is the primary means of hepatitis A virus transmission in the United States. Infections in the United States result primarily from travel to another country where hepatitis A virus transmission is common, close personal contact with infected persons, sex among men who have sex with men, having sex with someone who has the virus and behaviors associated with injection drug use ³⁾, ⁴⁾ [see ⁵⁾].

Exposure to contaminated food or water can cause common-source outbreaks and sporadic cases of Hepatitis A virus infection. Uncooked foods contaminated with Hepatitis A virus can be a source of outbreaks, as well as cooked foods that are not heated to temperatures capable of killing the virus during preparation (i.e., 185 degrees F [>85 degrees C] for one minute) and foods that are contaminated after cooking, as occurs in outbreaks associated with infected food handlers ⁶⁾. Waterborne outbreaks are infrequent in developed countries with properly maintained sanitation and water supplies ⁷⁾. In the United States, floods are unlikely to cause outbreaks of communicable diseases, and outbreaks of Hepatitis A virus caused by flooding have not been documented [see ⁸⁾].

Who is at increased risk for acquiring hepatitis A virus (HAV) infection ?

Persons with direct contact with persons who have hepatitis A
Travelers to countries with high or intermediate endemicity of hepatitis A virus infection
Men who have sex with men
Have any type of sexual contact with someone who has hepatitis A
Are HIV positive
Users of injection and non-injection drugs
Persons with clotting factor disorders, such as hemophilia
Persons working with nonhuman primates
Household members and other close personal contacts of adopted children newly arriving from countries with high or intermediate hepatitis A endemicity.

Hepatitis A Virus Genotypes

What are the different types of hepatitis A virus genotypes ?

There are 6 HAV genotypes, with only genotypes I, II and III infecting humans. HAV genotypes I, II and III are further divided into subtypes A and B. HAV genotypes and subtypes have a distinctive geographic distribution ⁹⁾.

HAV genotype I is the most common genotype occurring around the world
HAV genotype IA is prevalent in South and North America, Europe, Asia and Africa
HAV genotype IB is predominant in the Middle East and South Africa
HAV genotype II is not as common
HAV genotype III is common around the world
HAV genotype IIIA circulates in Asia, Europe, Madagascar and the USA.

What are the clinical implications of different HAV genotypes ?

No differences in clinical presentation of infections with different genotypes are clearly established. However, HAV genotype IB is found more frequently among acute liver failure cases compared to the non-liver failure cases, suggesting its potential greater virulence. Host factors such as age of patients and underlying liver diseases as well as viral factors such as HAV RNA levels and genomic mutations were reported in some studies to be associated with disease severity ¹⁰⁾.

How does hepatitis A genotyping help to establish transmission in an outbreak setting ?

Hepatitis A genotyping is done to determine genetic identity of the HAV sequences in an outbreak. Sequence differences in the VP1-P2A junction of the HAV genome has been widely used to identify HAV sub-genotypes, and evaluate genetic relatedness among sequences derived from hepatitis A infected individuals ¹¹⁾. Genotyping assists significantly in the identification of a common source of infection during hepatitis A outbreaks, especially when paired with epidemiologic evidence ¹²⁾.

What are the signs and symptoms of hepatitis A virus (HAV) infection ?

Among older children and adults, infection is typically symptomatic. Symptoms usually occur abruptly and can include the following:

Fever (low grade fever)
Fatigue
Loss of appetite
Sudden Nausea
Sudden Vomiting
Abdominal pain or discomfort, especially on the upper right side beneath your lower ribs (by your liver)
Dark urine
Clay-colored bowel movements
Joint pain
Jaundice or yellowing of the skin and the whites of your eyes
Intense itching

Most (70%) of infections in children younger than age 6 are not accompanied by symptoms. When symptoms are present, young children typically do not have jaundice; most (>70%) older children and adults with hepatitis A virus infection have this symptom ¹³⁾.

When to see your doctor

Make an appointment with your doctor if you have signs or symptoms of hepatitis A.

Getting a hepatitis A vaccine or an injection of immunoglobulin (an antibody) within two weeks of exposure to hepatitis A may protect you from infection. Ask your doctor or your local health department about receiving the hepatitis A vaccine if:

You’ve traveled out of the country recently, particularly to Mexico or South or Central America, or to areas with poor sanitation
A restaurant where you recently ate reports a hepatitis A outbreak
Someone close to you, such as a roommate or caregiver, is diagnosed with hepatitis A
You recently had sexual contact with someone who has hepatitis A

When symptoms occur, how long do they last ?

Symptoms of hepatitis A usually last less than 2 months, although 10%–15% of symptomatic persons have prolonged or relapsing disease for up to 6 months ¹⁴⁾.

What is the incubation period for hepatitis A virus (HAV) ?

The average incubation period for hepatitis A virus is 28 days (range: 15–50 days) ¹⁵⁾.

How long does hepatitis A virus (HAV) survive outside the body ?

Hepatitis A virus can live outside the body for months, depending on the environmental conditions.

How is the hepatitis A virus (HAV) killed ?

In contaminated food, hepatitis A virus is killed when exposed to temperatures of >185 degrees F (>85 degrees C) for 1 minute. However, the virus can still be spread from cooked food that is contaminated after cooking. Freezing does not inactivate hepatitis A virus.

Adequate chlorination of water, as recommended in the United States, kills hepatitis A virus that enters the municipal water supply ¹⁶⁾. Transmission of hepatitis A virus from exposure to contaminated water is considered rare given that no substantial or consistent increase in prevalence of anti-hepatitis A virus has been documented among sewage workers.

In the environment, hepatitis A virus can be killed by cleaning household or other facility surfaces with a freshly prepared solution of 1:100 dilution of household bleach to water ¹⁷⁾.

Can hepatitis A become chronic ?

No. Unlike other types of viral hepatitis, hepatitis A does not cause long-term liver damage, and it doesn’t become chronic.

Can persons become re-infected with hepatitis A ?

No. IgG antibodies to hepatitis A virus (HAV), which appear early in the course of infection, provide lifelong protection against the disease ¹⁸⁾.

How is HAV infection prevented ?

Vaccination with the full, two-dose series of hepatitis A vaccine is the best way to prevent HAV infection. Hepatitis A vaccine has been licensed in the United States for use in persons 1 year of age and older. Additional Guidance is available at: https://www.cdc.gov/mmwr/preview/mmwrhtml/rr5507a1.htm.

Immune globulin can provide short-term protection against hepatitis A, both pre- and post-exposure. Immune globulin must be administered within 2 weeks after exposure for maximum protection. Additional Guidance is available at: ¹⁹⁾

Given that the virus is transmitted through the fecal-oral route, good hand hygiene—including hand washing after using the bathroom, changing diapers, and before preparing or eating food—is integral to hepatitis A prevention ²⁰⁾.

Following are the updated recommended doses of GamaSTAN S/D for hepatitis A pre-exposure and post-exposure prophylaxis ²¹⁾.

Pre-exposure Prophylaxis in Persons Who Plan to Travel in Areas with High or Intermediate Hepatitis A Endemicity

The recommended dosages of GamaSTAN S/D, which vary according to planned duration of travel are as follows (see Table 1):

Up to 1 month: 0.1 mL/kg
Up to 2 months: 0.2 mL/kg
2 months or longer: repeat dose of 0.2 mL/kg every 2 months.

Table 1. Indications and updated dosage recommendations for GamaSTAN S/D human immune globulin for preexposure and postexposure prophylaxis against hepatitis A infection

Indication	Updated dosage recommendation
Preexposure prophylaxis
Up to 1 month of travel	0.1 mL/kg
Up to 2 months of travel	0.2 mL/kg
2 months of travel or longer	0.2 mL/kg (repeat every 2 months)
Postexposure prophylaxis	0.1 mL/kg

[Source ]

Pre-exposure Prophylaxis for International Travel

Hepatitis A vaccine at the age-appropriate dose is preferred to IG. For travel that will begin in ≤2 weeks to countries with high or intermediate hepatitis A endemicity, older adults, immunocompromised persons, and persons with chronic liver disease or other chronic medical conditions may receive IG simultaneously with hepatitis A vaccine at a separate anatomic injection site. Travelers who elect not to receive hepatitis A vaccine, who are aged <12 months, or who are allergic to a component of hepatitis A vaccine should receive a single dose of IG before travel ²³⁾.

Post-exposure Prophylaxis

IG should be used for children aged <12 months, immunocompromised persons, persons who have chronic liver disease, and persons for whom vaccine is contraindicated. IG is also preferred over hepatitis A vaccine for persons aged >40 years; however, vaccine may be used if IG cannot be obtained ²⁴⁾.

Postexposure Prophylaxis of Household and Institutional Hepatitis A Case Contacts

The recommended dosage of GamaSTAN S/D is 0.1 mL/kg (see Table 1 above). There is no maximum dosage of GamaSTAN S/D for hepatitis A prophylaxis ²⁵⁾.

The effect of IG preparations on the response to certain live-virus vaccines is unknown, but antibodies in GamaSTAN S/D might interfere with live-virus vaccines such as measles, mumps, and rubella (MMR) vaccine and varicella vaccine ²⁶⁾. The recommendations for the timing of administration of GamaSTAN S/D with live-virus vaccines has not changed ²⁷⁾. The Advisory Committee on Immunization Practices (ACIP) recommends that MMR and varicella vaccines should be administered at least 2 weeks before or at least 3 months after the administration of IG preparations ²⁸⁾. If an IG preparation must be administered less than 2 weeks after the administration of MMR or varicella vaccine, the patient should be revaccinated no sooner than 3 months after receipt of the IG preparation.

The absolute lower limit of anti-HAV IgG required to prevent HAV infection has not been defined; however, 10 mIU/mL is considered to be the minimum protective level for HAV prophylaxis ²⁹⁾. The minimum anti-HAV IgG potency specified by the European Pharmacopoeia for intramuscular IG preparations indicated for HAV prophylaxis is >100 IU/mL ³⁰⁾. A recent study showed that only two of nine tested lots of commercially available IG preparations manufactured in the United States, Europe, and Asia had anti-HAV IgG potency of 100 IU/mL ³¹⁾. In addition, anti-HAV IgG decay models indicate that only five of nine lots of IG dosed at 0.02 mL/kg achieved postabsorption plasma anti-HAV IgG levels above the minimum protective level of 10 mIU/mL ³²⁾. The decay model also showed that none of the tested IG lots maintained the proposed minimal protective anti-HAV IgG level of 10 mIU/mL for 3 months ³³⁾.

Indications for the use of IG are based on ACIP recommendations published in 2007 for prevention of hepatitis A infection after exposure to HAV and in international travelers ³⁴⁾.

Hepatitis A Vaccine

Who should be vaccinated against hepatitis A ?

The Advisory Committee on Immunization Practices (ACIP) recommends that the following persons be vaccinated against hepatitis A:

All children at age 1 year,
Persons who are at increased risk for infection,
Persons who are at increased risk for complications from hepatitis A, and
Any person wishing to obtain immunity (protection).

Children

Advisory Committee on Immunization Practices (ACIP) recommends that all children in the United States receive hepatitis A vaccine at 1 year of age (i.e., 12-23 months) to avoid interference by passive maternal anti-HAV that may be present during the first year of life. In the United States, children who are not vaccinated by 2 years of age can be vaccinated at subsequent visits; vaccination can be considered for children 2 to 18 years old and for anyone who wants protection against hepatitis A infection. Booster doses are not recommended. More information is available at: ³⁵⁾

Persons at Increased Risk for Hepatitis A Infection

Persons traveling to or working in countries that have high or intermediate endemicity of hepatitis A. Persons who travel to developing countries are at high risk for hepatitis A, even those traveling to urban areas, staying in luxury hotels, and those who report maintaining good hand hygiene and being careful about what they drink and eat [see ³⁶⁾].

Men who have sex with men. Men who have sex with men should be vaccinated.

Users of injection and non-injection drugs. Persons who use injection and non-injection drugs should be vaccinated.

Persons who have occupational risk for infection. Persons who work with HAV-infected primates or with HAV in a research laboratory setting should be vaccinated. No other groups have been shown to be at increased risk for HAV infection because of occupational exposure.

Persons who have chronic liver disease. Persons with chronic liver disease who have never had hepatitis A should be vaccinated, as they have a higher likelihood of having fulminant hepatitis A (i.e., rapid onset of liver failure, often leading to death). Persons who are either awaiting or have received liver transplants also should be vaccinated.

Persons who have clotting-factor disorders. Persons who have never had hepatitis A and who are administered clotting-factor concentrates, especially solvent detergent-treated preparations, should be vaccinated.

Household members and other close personal contacts of adopted children newly arriving from countries with high or intermediate hepatitis A endemicity. Previously unvaccinated persons who anticipate close personal contact (e.g., household contact or regular babysitting) with an international adoptee from a country of high or intermediate endemicity during the first 60 days following arrival of the adoptee in the United States should be vaccinated. The first dose of the 2-dose hepatitis A vaccine series should be administered as soon as adoption is planned, ideally 2 or more weeks before the arrival of the adoptee. More information is available at: ³⁷⁾.

Persons with direct contact with persons who have hepatitis A. Persons who have been recently exposed to hepatitis A virus and who have not previously received hepatitis A vaccine should be vaccinated. See ³⁸⁾

What is the Hepatitis A vaccine schedule and dosages ?

HAVRIX ^{® 1}

Licensed dosages and schedules for HAVRIX ® 1
Age	Dose (ELISA units)2	Volume (mL)	No. of doses	Schedule (mos)3
	720	0.5	2	0,6-12
	1,440	1.0	2	0,6-12

¹Hepatitis A vaccine, inactivated, GlaxoSmithKline.
²Enzyme-linked immunosorbent assay units.
³0 months represents timing of the initial dose; subsequent numbers represent months after the initial dose.

VAQTA ^{® 1}

Licensed dosages and schedules for VAQTA ® 1
Age	Dose (U.)2	Volume (mL)	No. of doses	Schedule (mos)3
12 mos–18 yrs	25	0.5	2	0,6-18
≥19 years	50	1.0	2	0,6-18

¹Hepatitis A vaccine, inactivated, Merck & Co., Inc.
²Units.
³0 months represents timing of the initial dose; subsequent numbers represent months after the initial dose.

TWINRIX ^{® 1} (HepAHepB) Vaccine Schedule (Not recommended for post exposure prophylaxis)

Licensed dosages and schedules for TWINRIX ® 1
Age	Dose (ELISA units)2	Volume (mL)	No. of doses	Schedule
≥ 18 yrs	720	1.0	3	0, 1, 6 mos
≥ 18 yrs	720	1.0	4	0, 7, 21–30 days + 12 mos3

¹Combined hepatitis A and hepatitis B vaccine, inactivated, GlaxoSmithKline.
²Enzyme-linked immunosorbent assay units.
³This 4-dose schedule enables patients to receive 3 doses in 21 days; this schedule is used prior to planned exposure with short notice and requires a fourth dose at 12 months.

Can hepatitis A vaccine be given during pregnancy ?

Yes ³⁹⁾. Hepatitis A vaccine is recommended for pregnant women with additional medical conditions or other indications for hepatitis A vaccine. The Adult Immunization Schedule by Medical and Other Indications is available at: ⁴⁰⁾

A recent review of the Vaccine Adverse Event Reporting System (VAERS) did not identify any concerning patterns of adverse events in pregnant women or their infants after hepatitis A vaccination (HAVRIX, VAQTA) or hepatitis A and B combined vaccination (TWINRIX) during pregnancy ⁴¹⁾. Pregnant women at risk for HAV infection during pregnancy should also be counseled concerning all options to prevent HAV infection.

Can Hepatitis A vaccine be given to immunocompromised persons (e.g., persons on hemodialysis or persons with AIDS) ?

Yes. Because hepatitis A vaccine is inactivated, no special precautions need to be taken when vaccinating immunocompromised persons.

Is it harmful to administer an extra dose(s) of hepatitis A vaccine or to repeat the entire vaccine series if documentation of vaccination history is unavailable ?

No. If necessary, administering extra doses of hepatitis A vaccine is not harmful.

Is it worthwhile to administer the first dose of hepatitis A vaccine if the timing of the second dose cannot be assured ?

Yes, It is not known for how long protection from one hepatitis A vaccine dose lasts, but it has been shown to last for at least 10 years ⁴²⁾. One dose of single-antigen hepatitis A vaccine administered at any time before International travel can provide adequate protection for most healthy persons ⁴³⁾.

Should pre-vaccination testing be performed before administering hepatitis A vaccine ?

To reduce the costs of vaccinating people who are already immune to hepatitis A, prevaccination testing is recommended only in certain persons, specific circumstances to reduce the costs of vaccinating people who are already immune to hepatitis A, including:

Persons who were born in geographic areas with high or intermediate prevalence of hepatitis A virus infection;
Older adolescents and adults in certain population groups (i.e., American Indians, Alaska Natives, and Hispanics); and
Adults in groups that have a high prevalence of infection (e.g., injection-drug users).

Pre-vaccination testing might also be warranted for older adults.

The decision to test should be based on ⁴⁴⁾:

The expected prevalence of immunity,
The cost of vaccination compared with the cost of serologic testing, and
The likelihood that testing will not interfere with initiation of vaccination.

Additional information is available at: ⁴⁵⁾

Should post-vaccination testing be performed ?

No. Postvaccination testing is not indicated because of the high rate of vaccine response among adults and children. In addition, not all testing methods approved for routine diagnostic use in the United States have the sensitivity to detect low, but protective, anti-HAV concentrations after vaccination. Additional information is available at ⁴⁶⁾.

How long does protection from hepatitis A vaccine last ?

The exact duration of protection after vaccination is unknown. Anti-HAV has been shown to persist for at least 20 years in adults administered inactivated vaccine as children with the three-dose schedule ⁴⁷⁾ and anti-HAV persistence of at least 20 years also was demonstrated among persons vaccinated with a two-dose schedule as adults ⁴⁸⁾. Detectable antibodies are estimated to persist for 40 years or longer based on mathematical modeling and anti-HAV kinetic studies ⁴⁹⁾.

Can hepatitis A vaccine be administered concurrently with other vaccines ?

Yes. Hepatitis B, diphtheria, poliovirus (oral and inactivated), tetanus, typhoid (oral and intramuscular), cholera, Japanese encephalitis, rabies, and yellow fever vaccines can be given at the same time that hepatitis A vaccine is given, but at a different injection site ⁵⁰⁾, ⁵¹⁾, ⁵²⁾. In studies among young children, simultaneous administration of hepatitis A vaccine did not affect the immunogenicity or reactogenicity of diphtheria-tetanus-acellular pertussis; inactivated polio; measles, mumps, rubella (MMR); hepatitis B; and Haemophilus influenzae type b vaccines ⁵³⁾.

Can a patient receive the first dose of hepatitis A vaccine from one manufacturer and the second (last) dose from another manufacturer ?

Yes. Results of several studies indicate that the response of adults administered hepatitis A vaccine according to a schedule that mixed the two single-antigen vaccines currently licensed in the United States was equivalent to that of adults vaccinated according to the licensed schedules with the single vaccine ⁵⁴⁾.

What should be done if an infant receives the first dose of hepatitis A vaccine at an age younger than 12 months ?

Although no known harm is associated with giving hepatitis A vaccine to infants, the hepatitis A vaccine dose(s) administered prior to 12 months of age might result in a suboptimal immune response, particularly in infants with passively acquired maternal antibody ⁵⁵⁾. Therefore, hepatitis A vaccine dose(s) administered at <12 months of age are not considered valid doses.

The hepatitis A vaccine two-dose series should be initiated starting at least 6 months after the last invalid dose and when the child is at least 1 year of age.

What should be done if the second (last) dose of hepatitis A vaccine is delayed ?

The second dose should be given as soon as possible. Even if the second does is delayed, the first dose does not need to be repeated.

How soon before international travel should the first dose of hepatitis A vaccine be given ?

The first dose of hepatitis A vaccine should be administered as soon as travel is considered.

For optimal protection, older adults, immunocompromised persons, and persons with chronic liver disease or other chronic medical conditions who are planning to depart in ≤2 weeks should receive the initial dose of vaccine and also can simultaneously be administered immune globulin at a separate anatomic injection site. Information on immune globulin dosing is available at ⁵⁶⁾.

Additional information on hepatitis A vaccine and travel is available at ⁵⁷⁾.

What should be done if a traveler cannot receive hepatitis A vaccine ?

Travelers who are allergic to a vaccine component, who elect not to receive vaccine, or who are aged <12 months should receive a single dose of immune globulin, which provides effective protection against Hepatitis A virus infection for up to 2 months depending on the dosage given.

Information on immune globulin dosing is available at ⁵⁸⁾

Who should receive protection against hepatitis A before travel ?

All susceptible persons traveling to or working in countries that have high or intermediate rates of hepatitis A should be vaccinated or receive immune globulin (IG) before traveling. Persons who travel to developing countries are at high risk for hepatitis A. Even those traveling to urban areas, staying in luxury hotels, and those reporting that they maintain good hand hygiene and are careful about what they drink and eat are at high risk. For more information on international travel and HAV, see CDC’s travel page at ⁵⁹⁾ or ACIP updated recommendations on Prevention of Hepatitis A after Exposure to Hepatitis A Virus and in International Travelers at ⁶⁰⁾.

Hepatitis A Vaccine Side Effects

HAVRIX ^®

In studies of adults and children 2 years of age and older, the most common solicited adverse events were injection site soreness (56% of adults and 21% of children) and headache (14% of adults and less than 9% of children) ⁶¹⁾.

In studies of children 11 to 25 months of age, the most frequently reported solicited local reactions were pain (32%) and redness (29%). Common solicited general adverse events were irritability (42%), drowsiness (28%), and loss of appetite (28%) ⁶²⁾.

VAQTA ^®

The most common local adverse reactions and systemic adverse events (≥15%) reported in different clinical trials across different age groups when VAQTA was administered alone or concomitantly were ⁶³⁾:

Children — 12 through 23 months of age: injection-site pain/tenderness (37.0%), injection-site erythema (21.2%), fever (16.4% when administered alone, and 27.0% when administered concomitantly).
Children/Adolescents — 2 through 18 years of age: injection-site pain (18.7%).
Adults — 19 years of age and older: injection-site pain, tenderness, or soreness (67.0%), injection-site warmth (18.2%) and headache (16.1%).

TWINRIX ^®

Following any dose of TWINRIX, the most common (≥10%) solicited injection site reactions were injection site soreness (35% to 41%) and redness (8% to 11%); the most common solicited systemic adverse events were headache (13% to 22%) and fatigue (11% to 14%) ⁶⁴⁾.

Hepatitis A Outbreak

For the current U.S. outbreaks among people who are homeless and/or people who use injection and non-injection drugs, Centers for Disease Control and Prevention (CDC) has provided interim outbreak-specific guidance on hepatitis A vaccine administration.

Post exposure prophylaxis is recommended for unvaccinated people who have been exposed to hepatitis A virus (HAV) in the last 2 weeks; those with evidence of previous vaccination do not require post exposure prophylaxis .

Post exposure prophylaxis consists of:

Hepatitis A vaccine for people aged 1-40 years
Hepatitis A virus-specific immunoglobulin (IG) for people outside of this age range. If immunoglobulin is not available, hepatitis A vaccine can be substituted

NOTE: CDC recommends that all children be vaccinated against hepatitis A at age 1 year. Parents or caregivers who are unsure if a child has been vaccinated should consult the child’s health-care provider to confirm vaccination status.

Hepatitis A Treatment

No specific treatment exists for hepatitis A. Your body will clear the hepatitis A virus on its own. In most cases of hepatitis A, the liver heals within six months with no lasting damage.

Hepatitis A treatment usually focuses on keeping comfortable and controlling signs and symptoms. You may need to ⁶⁵⁾:

Rest. Many people with hepatitis A infection feel tired and sick and have less energy.
Manage nausea. Nausea can make it difficult to eat. Try snacking throughout the day rather than eating full meals. To get enough calories, eat more high-calorie foods. For instance, drink fruit juice or milk rather than water. Drinking plenty of fluids is important to prevent dehydration if vomiting occurs.
Avoid alcohol and use medications with care. Your liver may have difficulty processing medications and alcohol. If you have hepatitis, don’t drink alcohol. It can cause more liver damage. Talk to your doctor about all the medications you take, including over-the-counter drugs.

Lifestyle and home remedies

You can take steps to reduce the risk of passing hepatitis A to others.

Avoid sexual activity. Avoid all sexual activity if you have hepatitis A. Many kinds of sexual activity can spread the infection to your partner. Condoms don’t offer adequate protection.
Wash your hands thoroughly after using the toilet and changing diapers. Scrub vigorously for at least 20 seconds and rinse well. Dry your hands with a disposable towel.
Don’t prepare food for others while you’re actively infected. You can easily pass the infection to others.

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