The mysterious outbreak of Hepatitis A in Los Angeles

Media organisations in the US and around the world were shocked to discover a new outbreak of Hepatitis A in Los Angeles, California.

Local authorities declared a community-wide outbreak of the highly contagious infection, which can cause serious health damage if left untreated.

The Los Angeles Department of Public Health confirmed 165 Hepatitis A cases in the county since 2024, three times the number of cases reported in 2023. Counts continue to climb as public health officials attempt to address the issue. A further 29 cases were confirmed in the first three months of 2025, double the number of the same period last year.

The Los Angeles Times reports that seven deaths have been linked to the 13-month-old outbreak.

Dr. Sharon Balter, director of the country’s Division of Communicable Disease Control and Prevention, told the LA Times: “We definitely think that the outbreak is bigger than the numbers imply.”

Hepatitis A can cause serious health issues if left untreated. Contact Better2Know today to book your STI test.

What caused the outbreak?

Health officials are still unsure what has caused the outbreak, and investigations into its cause are ongoing.

The outbreak began to emerge in LA County wastewater data. Testing wastewater for certain infections often provides a clearer picture of the scale of an outbreak, as many infected individuals may not seek care and treatment when they are unwell. These individuals may not realise they have the infection, or they may lack access to healthcare.

Genetic analysis of samples identified that the strain in this outbreak was primarily found in the region. Subsequent reports have shown that the infection is spreading among the city’s homeless population, the prison population, and even among employees at local grocery storesandrestaurants.

Historically, Hepatitis A infections tend to be identified in homeless people. This is because homeless people have limited access to toilets and handwashing facilities, allowing the infection to spread more easily.

Other risk factors for getting Hepatitis A include:

• Visiting parts of the world where Hepatitis A is common, like South and Central Africa, eastern Europe and parts of Asia
• Experiencing homelessness
• Men who have sex with men
• People who use needles to inject recreational and illegal drugs

However, most people contracting Hepatitis A do not possess these risk factors, making it all the more crucial to identify the cause of the outbreak.

Hepatitis A cases in the US fell 95.5% from 1996 to 2011, according to the Centre for Disease Control (CDC), but surged back in 2016. The current outbreak follows one in LA County in 2017 and another in San Diego County from 2016 to 2018.

What is Hepatitis A?

Hepatitis A is a virus that affects the liver. It is often found in countries with inadequate sewage disposal systems and poor water quality.

How does Hepatitis A spread?

Hepatitis A is a sexually transmitted infection (STI), so it can be contracted through unprotected sexual activity, including vaginal and anal intercourse.

However, Hepatitis A can also spread non-sexually through contaminated food (primarily fruits and vegetables that aren’t washed before eating), contaminated water, sharing cutlery and needles for drugs, and person-to-person skin contact.

What are the symptoms?

Most people who get Hepatitis A won’t experience any symptoms, so the only way to know if you have it is to get tested.

When symptoms do occur, they tend to appear around four weeks after the initial infection and go away within a few months. The main symptoms can include:

• Fatigue
• Physical weakness
• Headaches
• Fever
• Nausea
• Vomiting
• Stomach pain
• Dark brown urine
• Pale yellow or grey bowel movements
• Diarrhoea
• Jaundice – yellowing skin or white of the eyes, itchy skin or rash, and a swollen liver

Hepatitis A can be tricky to diagnose because the early symptoms can easily be mistaken for gastroenteritis or stomach flu.

Is there a vaccine for Hepatitis A?

There is a vaccine for Hepatitis A that is both safe and effective. The CDC advises that children receive their vaccination by the age of two.

However, most people can and ought to get vaccinated if they haven’t already or if they’re uncertain about whether they’ve been vaccinated in the first place.

Are there other ways to avoid getting Hepatitis A?

Vaccination is the best way to avoid contracting Hepatitis A, but there are other ways to stay safe.

Wash your hands thoroughly before preparing any meals and going to the toilet. Soap and warm water should do the trick. If you’re using hand sanitiser, use one with an alcohol concentration of 60% or more. Lower-alcohol options don’t always eliminate the virus.

Final thoughts

Hepatitis A is making a comeback, and not just in the US. If you think you may have been exposed to this infection, click the button below to get tested at a sexual health clinic near you.

Don’t leave your sexual health to chance. Book an STI test at a sexual health clinic near you.