World Hepatitis Day (WHD) takes place every year on 28 July to help raise awareness of viral hepatitis and highlight the need for a greater global response.

According to the World Health Organisation (WHO), the date of 28 July was chosen because it is the birthday of Nobel-prize winning scientist Dr Baruch Blumberg, who discovered the hepatitis B virus (HBV) and developed a diagnostic test and vaccine for it.

The health agency reports that viral hepatitis B and C affect 325m people worldwide causing 1.4 million deaths a year.

It is the second major killer infectious disease after tuberculosis, and nine times more people are infected with hepatitis than HIV. 

WHO states that hepatitis is preventable, treatable, and in the case of hepatitis C, curable. However, over 80 per cent of people living with hepatitis are lacking prevention, testing and treatment services.

So what are the symptoms of hepatitis and can it be treated? Here's everything you need to know.

- What is hepatitis?

Hepatitis is the term used to describe inflammation of the liver, the NHS states.

Hepatitis viruses are the most common cause of hepatitis in the world but other infections, toxic substances, and autoimmune diseases can also cause hepatitis.

There are several different types of hepatitis and while some will pass without any serious problems, others can be long-lasting and cause scarring of the liver (cirrhosis), loss of liver function and, in some cases, liver cancer.

- What are the symptoms of hepatitis?

Short-term hepatitis often has no noticeable symptoms, so many people do not realise they have it. However, if symptoms do develop, the NHS states they can include:

muscle and joint pain

a high temperature

feeling and being sick

feeling unusually tired all the time 

a general sense of feeling unwell 

loss of appetite 

tummy pain

dark urine 

pale, grey-coloured poo 

itchy skin

yellowing of the eyes and skin (jaundice)

The NHS adds that long-term hepatitis also may not have any obvious symptoms until the liver stops working properly and may only be picked up during blood tests.

In the later stages it can cause jaundice, swelling in the legs, ankles and feet, confusion, and blood in stools or vomit.

- What are the different types hepatitis?

There are a number of different types of hepatitis including A, B, C, D, E, alcoholic and autoimmune.

More information on the different types below.

1. Hepatitis A

The NHS states that hepatitis A is caused by the hepatitis A virus. 

It is typically caught by consuming food and drink contaminated with the faeces of an infected person, and is most common in countries where sanitation is poor.

Hepatitis A usually passes within a few months, although it can occasionally be severe and even life threatening.

There is no specific treatment for it, other than to relieve symptoms like pain, nausea and itching.

2. Hepatitis B

Hepatitis B is caused by the hepatitis B virus, which is spread in the blood of an infected person, the NHS states.

It is a common infection worldwide and is usually spread from infected pregnant women to their babies, or from child-to-child contact. 

In rare cases, it can be spread through unprotected sex and injecting drugs.

Most adults infected with hepatitis B are able to fight off the virus and fully recover from the infection within a couple of months.

But most people infected as children develop a long-term infection. This is known as chronic hepatitis B and can lead to cirrhosis and liver cancer. Antiviral medication can be used to treat it.

3. Hepatitis C 

Hepatitis C is caused by the hepatitis C virus and is the most common type of viral hepatitis in the UK, the NHS states.

It is usually spread through blood-to-blood contact with an infected person.

In the UK, it is most commonly spread through sharing needles used to inject drugs.

Poor healthcare practices and unsafe medical injections are the main way it is spread outside the UK.

Hepatitis C often causes no noticeable symptoms, or only flu-like symptoms, so many people are unaware they're infected.

Around 1 in 4 people will fight off the infection and be free of the virus. In the remaining cases, it'll stay in the body for many years. This is known as chronic hepatitis C and can cause cirrhosis and liver failure.

Chronic hepatitis C can be treated with very effective antiviral medications, but there's currently no vaccine available.

4. Hepatitis D

Hepatitis D is caused by the hepatitis D virus. It only affects people who are already infected with hepatitis B, as it needs the hepatitis B virus to be able to survive in the body.

Hepatitis D is usually spread through blood-to-blood contact or sexual contact, the NHS states.

Long-term infection with hepatitis D and hepatitis B can increase the risk of developing serious problems, such as cirrhosis and liver cancer.

There is no vaccine specifically for hepatitis D, but the hepatitis B vaccine can help protect people from it.

5. Hepatitis E

The NHS states that hepatitis E is caused by the hepatitis E virus. The number of cases in Europe has increased in recent years and it is now the most common cause of short-term hepatitis in the UK.

The virus has been mainly associated with the consumption of raw or undercooked pork meat or offal, but also with wild boar meat, venison and shellfish. 

Hepatitis E is generally a mild and short-term infection that does not require any treatment, but it can be serious in some people, such as those who have a weakened immune system.

6. Alcoholic hepatitis 

Alcoholic hepatitis is a type of hepatitis caused by drinking excessive amounts of alcohol over many years, the NHS states.

The condition is common in the UK and many people do not realise they have it.

This is because it does not usually cause any symptoms, although it can cause sudden jaundice and liver failure in some people.

Stopping drinking will usually allow the liver to recover, but there is a risk of eventually developing cirrhosis, liver failure or liver cancer if a person continues to drink alcohol excessively.

7. Autoimmune hepatitis

Autoimmune hepatitis is a rare cause of long-term hepatitis in which the immune system attacks and damages the liver, the NHS states.

Eventually, the liver can become so damaged that it stops working properly.

Treatment for autoimmune hepatitis involves very effective medicines that suppress the immune system and reduce inflammation.

It is not clear what causes autoimmune hepatitis and it is not known whether anything can be done to prevent it.