Hepatitis A can begin with fever and flu-like symptoms such as tiredness, headache, muscle aches, and loss of appetite. Some people also develop nausea, vomiting, or discomfort in the upper abdomen. Dark urine, pale stools, or yellowing of the eyes or skin may appear later. Not everyone has symptoms, especially young children, and a blood test is needed to confirm hepatitis A.
What do fever and flu-like symptoms of hepatitis A feel like?
Hepatitis A is a viral infection that causes inflammation of the liver. In its early stages, it can feel similar to the flu or another common viral illness. A person may experience a fever, low energy, headache, or muscle aches before noticing signs that suggest a problem involving the liver.
According to the Centers for Disease Control and Prevention (CDC), symptoms can include fever, fatigue, joint pain, nausea, vomiting, abdominal pain, and loss of appetite. Some people experience only a few of these symptoms, while others have no noticeable illness.
These early symptoms are not unique to hepatitis A. Influenza, other viral infections, and several digestive conditions can cause similar problems. The timing of symptoms, possible exposure to the virus, and any changes in urine, stools, or skin color can help a healthcare professional decide whether testing is appropriate.
Which symptoms may appear alongside a fever?
Fever may be one of the first noticeable signs of hepatitis A. As the illness develops, digestive symptoms and changes associated with liver inflammation may become more apparent. The pattern differs from person to person, and some individuals never develop the full range of symptoms.
- Fever: A raised body temperature may occur during the early stage of illness.
- Fatigue and weakness: Everyday activities may become more tiring, and the person may need additional rest.
- Headache and muscle aches: These flu-like complaints may occur along with a general feeling of being unwell.
- Loss of appetite: Food may seem less appealing, sometimes alongside nausea.
- Nausea, vomiting, or diarrhea: Digestive symptoms can make eating and drinking difficult.
- Abdominal discomfort: Pain or tenderness may occur in the upper abdomen, particularly on the right side, where the liver is located.
- Dark urine and pale stools: Urine may become darker than usual, while stools may appear unusually light or clay-colored.
- Jaundice: The whites of the eyes or skin may turn yellow. This change can be harder to notice on darker skin tones.
- Itching or joint pain: Some people develop itchy skin or aching joints during the illness.
The UK National Health Service (NHS) describes flu-like symptoms, including tiredness, headache, and muscle pains, among the possible early features of hepatitis A. These symptoms may occur before more recognizable signs, such as dark urine, pale stools, or jaundice.
When do hepatitis A fever and flu-like symptoms start?
Hepatitis A symptoms usually develop between two and seven weeks after exposure to the virus. The CDC reports an average incubation period of about 28 days, although the time between exposure and illness varies. This delay means that someone may not connect a recent illness with an earlier exposure to contaminated food or water or contact with an infected person.
Fever, fatigue, and reduced appetite may occur early. Digestive symptoms can follow, and some people later notice dark urine, pale stools, or yellowing of the eyes or skin. These changes do not necessarily occur in a fixed order. Jaundice may be absent, especially in young children, so its absence does not rule out infection.
According to the CDC, adults are more likely than children to develop recognizable symptoms. Children younger than six years often have no obvious symptoms, while older children and adults are more likely to experience a noticeable illness. When symptoms do occur, they generally resolve within two months, although some people remain unwell or experience returning symptoms for as long as six months.
How is hepatitis A different from the flu?
Hepatitis A and influenza can both cause fever, tiredness, and muscle aches. However, hepatitis A affects the liver, so changes in urine or stool color, jaundice, reduced appetite, nausea, and upper abdominal discomfort may provide important additional clues.
Influenza more commonly presents as a respiratory illness, often with cough, sore throat, or a runny or blocked nose. These differences can help guide an assessment, but they are not enough to establish a diagnosis. Symptoms overlap with other infections, and a person with hepatitis A may initially feel as though they have an ordinary viral illness.
For that reason, a persistent or unexplained fever accompanied by dark urine, pale stools, yellowing of the eyes or skin, or recent contact with someone who has hepatitis A deserves medical assessment. A healthcare professional can consider the full symptom pattern and exposure history rather than relying on one symptom alone.
How do doctors confirm whether the symptoms are caused by hepatitis A?
Symptoms alone cannot reliably distinguish hepatitis A from other viral infections or other forms of hepatitis. According to the CDC's clinical guidance on hepatitis A testing, a blood test is used to confirm a suspected infection. Testing is particularly relevant when symptoms are consistent with hepatitis A or a possible exposure has occurred.
The healthcare professional may ask when the fever started, whether the person has experienced nausea or abdominal discomfort, and whether there has been recent travel, consumption of potentially contaminated food or water, or close contact with an infected person. A physical examination and additional blood tests may help assess the liver and the person's overall condition.
One important test looks for immunoglobulin M antibodies to the hepatitis A virus, commonly called IgM anti-HAV. Detecting these antibodies can indicate a current or recent infection. Other antibody tests may show immunity from previous infection or vaccination, so results need to be interpreted in the appropriate clinical context.
When should you seek medical care for fever and flu-like symptoms?
Arrange a medical assessment if fever and flu-like symptoms occur alongside dark urine, pale stools, yellowing of the eyes or skin, or unexplained discomfort in the upper abdomen. Seek advice promptly if you believe you have been exposed to hepatitis A, even if symptoms have not yet developed.
Some people need more urgent assessment because hepatitis A can be more serious in certain circumstances. The NHS advises prompt medical contact when hepatitis A is suspected in someone who is pregnant, older than 60, or living with a liver condition. People with persistent vomiting, difficulty keeping fluids down, significant worsening of symptoms, confusion, or unusual drowsiness should also seek urgent medical attention.
Older adults and people with existing liver disease have a greater risk of severe illness. A clinician can assess these factors alongside symptoms and test results to determine what care is needed.
What can help during recovery from hepatitis A?
There is no specific antiviral medicine that cures hepatitis A. According to the CDC's clinical care guidance, treatment generally focuses on supportive care while the body recovers. This usually includes adequate rest, a balanced diet, and sufficient fluids. People who develop more serious symptoms may need hospital care.
Fever, nausea, and fatigue can affect daily activities, so rest and regular fluid intake are important. If vomiting or diarrhea makes drinking difficult, seek medical advice rather than allowing dehydration to develop. Appetite may return gradually, and tiredness can persist even after the initial flu-like symptoms improve.
Avoid alcohol while recovering, and check with a healthcare professional before using medicines or supplements that may affect the liver. Do not assume that common fever or pain medicines are appropriate for every person with suspected liver inflammation. A clinician or pharmacist can help identify suitable options based on age, medical history, and other medicines being taken.
Hepatitis A does not usually cause long-term liver infection, and most people recover fully. However, the recovery period may be prolonged, and symptoms can sometimes return. Follow-up care and any recommended blood tests help clinicians assess recovery when needed.
Can hepatitis A spread to other people during the early illness?
Yes. Hepatitis A spreads mainly through the fecal-oral route, when tiny amounts of infected stool enter another person's mouth through contaminated food, water, hands, or objects. An infected person may transmit the virus before realizing that they are ill, so the absence of jaundice does not mean that transmission is impossible.
Wash hands carefully with soap and water after using the toilet and before preparing or eating food. Avoid preparing food for others while infectious, and follow advice from a healthcare professional or local public health service about preventing further spread.
If you have had close contact with someone diagnosed with hepatitis A and are not vaccinated or otherwise known to be immune, contact a healthcare professional promptly. The hepatitis A vaccine, and in selected circumstances immune globulin, may help prevent illness when given within two weeks of exposure. Recommendations depend on factors such as age, vaccination history, and underlying health conditions.