# Hepatitis A

> The content on this page is for informational and educational purposes only. It does not constitute medical advice, diagnosis, or treatment recommendations. If you have health concerns, consult a qualified healthcare professional. Medova is not a medical service provider.

Source: https://medova.health/en/knowledge/diseases/hepatitis-a · Language: en

## Overview

Acute viral liver infection transmitted through contaminated food and water. The most common vaccine-preventable travel disease worldwide.

## Medical Information

- ICD-10: B15
- ICD-11: 1D50
- Causative Agent: virus
- Severity: Moderate
- Incubation Period: 15–50 days
- Mortality Rate: 0.3%
- Vaccine available: Yes

## Symptoms

- Abdominal pain (60%)
- Dark urine (80%)
- Fatigue (80%)
- Fever (70%)
- Hepatomegaly (60%)
- Jaundice (70%)
- Loss of appetite (80%)
- Malaise (75%)
- Nausea (70%)
- Headache (50%)
- Itching (40%)
- Myalgia (50%)
- Vomiting (40%)
- Weight loss (30%)
- Arthralgia (15%)
- Diarrhea (20%)
- Splenomegaly (15%)
- Rash (5%)

## Transmission

- Fecal Oral (Primary route)
- Blood transfusion
- Contaminated Food
- Contaminated Water
- Direct Contact

## Overview

Highly contagious liver infection caused by the hepatitis A virus.

## Overview

Hepatitis A is caused by the Hepatitis A virus (HAV), a non-enveloped RNA virus of the family Picornaviridae. Transmission occurs via the fecal-oral route — through ingestion of contaminated water or food (especially raw shellfish, unpeeled fruits, salads), direct person-to-person contact, or rarely through blood. The virus is highly stable in the environment, surviving weeks on surfaces and resistant to freezing. Unlike hepatitis B and C, hepatitis A does not cause chronic infection; recovery confers lifelong immunity.

## Emergency Signs

Seek emergency medical care immediately if:

- Persistent vomiting with inability to keep fluids down

- Severe abdominal pain (especially right upper quadrant)

- Signs of liver failure: confusion, drowsiness, personality changes (hepatic encephalopathy)

- Bruising or bleeding easily (coagulopathy)

- Very dark urine with pale stools and worsening jaundice after initial improvement

- Fever returning after jaundice has appeared

## Detailed Symptoms

Incubation period: 15–50 days (average 28–30 days). Clinical presentation varies with age:

**Children <6 years:** Usually asymptomatic (>70% of cases) or mild non-specific illness without jaundice.

**Older children and adults — prodromal phase (5–7 days):**

- Abrupt onset of fatigue, malaise, and anorexia

- Nausea, vomiting, and abdominal discomfort (right upper quadrant)

- Low-grade fever (38–39°C)

- Myalgia and arthralgia

**Icteric phase (2–6 weeks):**

- Jaundice (scleral icterus progressing to skin yellowing)

- Dark urine (cola-colored) — often the first sign noticed

- Pale/clay-colored stools (acholic)

- Hepatomegaly with tenderness

- Pruritus (itching) in some patients

- Paradoxical improvement — fever and GI symptoms often resolve as jaundice appears

**Recovery phase:** Gradual resolution over weeks to months. Fatigue may persist for several months.

## Course of Disease

Hepatitis A typically resolves within 2-6 months. Rarely, it can cause acute liver failure.

## Diagnosis

Laboratory confirmation:

- **Anti-HAV IgM:** Positive at symptom onset, detectable for 3–6 months — confirms acute infection

- **Anti-HAV IgG:** Appears during convalescence, persists lifelong — indicates past infection or vaccination

- **Liver function tests:** ALT/AST markedly elevated (often >1,000 IU/L), bilirubin elevated in icteric cases

- **HAV RNA (RT-PCR):** Available in reference labs; useful for outbreak investigation and genotyping

- **Stool HAV detection:** Virus shed in stool 1–2 weeks before symptoms through ~1 week after jaundice onset

Differential diagnosis: hepatitis B, C, E; EBV; CMV; leptospirosis; drug-induced liver injury.

## Treatment

No specific antiviral therapy exists. Management is supportive:

- **Rest and hydration:** Avoid strenuous activity during acute phase

- **Nutrition:** Small, frequent meals

- avoid alcohol for ≥6 months after illness (hepatotoxicity risk)

- **Symptom relief:** Antiemetics for nausea

- cholestyramine for pruritus

- avoid hepatotoxic medications (paracetamol limited to <2 g/day)

- **Monitoring:** Serial liver function tests in severe cases

- **Hospitalization criteria:** Persistent vomiting, INR >1.5, encephalopathy signs, inability to maintain hydration

- **Fulminant hepatitis (<1% of cases):** Requires ICU care

- liver transplantation may be needed

- Most patients recover completely within 2–6 months with no residual liver damage.

## Prevention Details

**Vaccination (primary prevention):**

- **Inactivated HAV vaccine:** 2-dose schedule — dose 1 provides ~95% protection within 2–4 weeks; dose 2 at 6–12 months for long-term immunity (estimated 25–40+ years, possibly lifelong)

- **Combined HAV/HBV vaccine (Twinrix):** 3-dose schedule (0, 1, 6 months) or accelerated (0, 7, 21 days + 12-month booster)

- **Pre-travel:** Vaccinate ≥2 weeks before departure; single dose protects most travelers

- **Post-exposure prophylaxis:** HAV vaccine within 2 weeks of exposure (for healthy persons 1–40 years); immunoglobulin for <12 months, >40 years, immunocompromised, or chronic liver disease patients

**Food and water hygiene:**

- Drink only bottled or boiled water; avoid ice

- Eat thoroughly cooked food; peel fruits yourself

- Avoid raw shellfish (filter-feeding shellfish concentrate HAV)

- Strict hand hygiene with soap after toilet use and before eating

## Travel Advice

Risk to travelers:

- **High risk:** All destinations in Africa, Asia (except Japan), Central and South America, Eastern Europe, the Middle East

- Hepatitis A is the #1 vaccine-preventable travel infection — vaccinate before ALL travel to endemic regions, regardless of trip duration or accommodation standard

- Luxury resorts and business hotels are NOT protective — HAV outbreaks have occurred in 4-5 star hotels

- Single dose provides rapid protection (2 weeks); schedule dose 2 upon return for long-term immunity

- Combined HAV/HBV vaccine (Twinrix) is efficient for frequent travelers

- Practice strict food and water hygiene even when vaccinated (vaccine is ~95%, not 100% effective)

- Travelers with chronic liver disease should be prioritized for vaccination — hepatitis A superinfection carries high mortality

## How common is it?

Hepatitis A is the most common vaccine-preventable infection in travelers. WHO estimates ~159 million new infections annually (2019 data), with ~39,000 deaths. Prevalence correlates inversely with sanitation:

- **High endemicity:** Sub-Saharan Africa, South Asia, Central America — nearly universal childhood infection; most adults immune

- **Intermediate:** Eastern Europe, Middle East, Latin America — shifting epidemiology with rising adult susceptibility

- **Low endemicity:** Western Europe, North America, Japan, Australia — susceptible adult populations at risk when traveling

Outbreaks occur via contaminated water supplies, food handlers, MSM populations, PWID, and institutional settings. Seroprevalence in returning travelers with acute hepatitis: HAV is the cause in ~40% of cases (GeoSentinel data). Attack rate among unvaccinated travelers to endemic areas: 3–20 per 1,000 person-months of travel.

## Risk Factors

Traveling to endemic areas, consuming contaminated food or water, poor hygiene practices.

## Complications Details

Hepatitis A is generally self-limiting, but complications increase with age and pre-existing liver disease:

- **Prolonged/relapsing hepatitis:** 10–15% of cases

- symptoms relapse 1–3 months after initial resolution, may last up to 6 months

- **Cholestatic hepatitis:** Prolonged jaundice (>3 months) with intense pruritus

- excellent prognosis

- **Fulminant hepatic failure:** <1% overall (higher in patients >50 years and those with chronic hepatitis B or C)

- mortality 50–70% without transplantation

- **Autoimmune hepatitis trigger:** HAV may trigger autoimmune hepatitis in genetically predisposed individuals

- **Extrahepatic manifestations (rare):** Vasculitis, arthritis, cryoglobulinemia, acute kidney injury, aplastic anemia, pancreatitis

- **Case fatality rate:** 0.1% in children <15 years

- 0.3% in adults 15–39

- 2.1% in adults ≥40 (WHO data)

## Recovery & Outlook

Prognosis is excellent with supportive care. Most people recover completely within 2-6 months.

## Available Vaccines

- [Hepatitis A Vaccine](https://medova.health/en/knowledge/vaccines/hepatitis-a-vaccine)
- [Hepatitis AB Combo Vaccine](https://medova.health/en/knowledge/vaccines/hepatitis-ab-combo-vaccine)

## Sources & content verification

- Data sources: WHO/ICD-11, CDC Yellow Book 2024, ECDC (SafeTripVax QMR-004, 2026-03-23), WHO Disease Factsheets 2024 + CDC Travelers' Health 2024 + Heymann CDD 21st ed.
- Generated by: AI + Human review
- Review status: Awaiting medical review
- Last updated: 2026-03-29
- [www.who.int](https://www.who.int/emergencies/disease-outbreak-news)

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The content on this page is for informational and educational purposes only. It does not constitute medical advice, diagnosis, or treatment recommendations. If you have health concerns, consult a qualified healthcare professional. Medova is not a medical service provider.

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