Hepatitis B (Acute)

107 cases in 2024 — near the 5-year baseline of ~184.

What is it?

Acute hepatitis B is the initial phase of infection with the hepatitis B virus (HBV). NYS had 107 acute cases in 2024. About 95% of adults infected with hepatitis B recover completely and develop immunity. However, infants and young children who are infected are much more likely to develop chronic hepatitis B, which significantly increases risk of liver cirrhosis and liver cancer.

How it spreads

Spreads through contact with infected blood, semen, vaginal fluids, and other body fluids. Routes include sharing needles or drug equipment, unprotected sex, needlestick injuries in healthcare settings, and from an infected mother to her newborn during delivery.

Symptoms

Many acute infections cause no symptoms. When present (appearing 1–4 months after exposure): fatigue, nausea, vomiting, abdominal pain, dark urine, clay-colored stools, joint pain, and jaundice. Symptoms typically resolve within a few months.

Who is at risk?

People who inject drugs, men who have sex with men, people with multiple sexual partners, healthcare workers exposed to blood, unvaccinated infants born to infected mothers, and household contacts of people with chronic hepatitis B.

What you can do

Vaccine information

Hepatitis B vaccine is highly effective and recommended for all children (starting at birth) and adults not previously vaccinated. A 2- or 3-dose series provides lasting immunity for most people.

Based on NYSDOH annual communicable disease report. Threat level reflects 2024 case counts compared to the 5-year baseline.