The Hepatitis A virus is a non-enveloped single-stranded RNA virus.
Spread via the faeco-oral route, hepatitis A belongs to the Hepatovirus genus of the Picornaviridae family. Hand washing and good hand hygiene are key to reducing transmission.
It causes a viral hepatitis, and is frequently seen in travellers to endemic areas and those engaging in higher-risk sexual activities.
The majority of adults infected experience symptoms (approx 70-95%). Commonly a mild self-limiting illness manifesting with flu like symptoms, abdominal discomfort and nausea. Children under the age of 5 are frequently asymptomatic.
Though uncommon in the UK, there are a number of at risk groups.
Hepatitis A is said to follow four clinical phases (though significant variation exists).
Hepatitis A tends to cause a mild illness characterised by a flu-like illness and GI upset.
NOTE: One unusual symptom seen in smokers is a sudden distaste for cigarettes.
Hepatitis A IgM and Hepatitis A IgG antibodies (HAV-IgM, HAV-IgG) may be used to diagnose the infection.
HAV-IgM is positive soon after symptoms develop and tends to remain detectable for a few months. HAV-IgG becomes positive 5-10 days after symptoms develop and remains lifelong.
Repeat serology may be sent if negative but the patient is in the first 7-10 days of symptomatic disease.
NOTE: A hepatitis A RNA PCR has been developed but is not commonly available.
Management tends to be supportive except in the most severe cases.
The majority of patients do not need hospital admission. However any patient who is unwell or has significant liver impairment should be admitted and referred to hepatology.
The information on the impact of hepatitis A on pregnancy is limited. There is thought to be an increased risk of miscarriage or pre-term labour when it occurs in the second and third trimester.
Breastfeeding is not known to transmit the virus. Good personal hygiene is advised.
Clinicians should contact their local Health Protection Unit to allow contact tracing and monitoring of outbreaks.
In England hepatitis A is a ‘notifiable disease’, meaning you must notify a Proper Officer of the local authority.
At risk contacts should be reviewed, if they have not been vaccinated, immunoglobulin should be considered. Typically the hepatitis vaccine will be offered.
Hepatitis A vaccine is recommended to those at risk of infection and at risk of complications off infection.
Individuals who should be offered vaccination include:
It is available as a monovalent vaccine or in combination with hepatitis B or typhoid. The contents of each vaccine and the patients allergy status must be checked.
The first dose should be given at least 2-3 weeks prior to travel. Extra doses may be recommended if long term protection is needed.
Rarely hepatitis A leads to more serious illness and complications needing specialist care.
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