What is viral gastroenteritis?

Viral gastroenteritis (gastro) is a common infection of the stomach and intestines that causes vomiting and diarrhoea.

Gastro can be caused by many different viruses. Examples of viruses that cause gastro are rotavirus and norovirus.

There are many other causes of gastro including bacteria, toxins, parasites, and some other diseases.

What are the symptoms of viral gastroenteritis?

The symptoms of gastro can include:

• vomiting
• watery diarrhoea
• nausea
• fever
• abdominal pain
• headache
• muscle aches
• dehydration (from diarrhoea and vomiting)

Depending on the cause, symptoms usually take between one and three days to start. Symptoms usually last one to two days, or sometimes longer.

How is viral gastroenteritis spread?

Viral gastroenteritis can be highly infectious so it can spread very easily.

It spreads when a person comes in contact with the vomit or faeces (poo) of an infected person, including:

• person-to-person contact, for example shaking hands with someone who has been sick and has the virus on their hands
• contaminated objects
  
• contaminated food or drink

Infection may also be spread in the air when people vomit.

In most cases it is spread from a person who has symptoms.

Some people can pass on the infection without having symptoms. It is important to continue good hygiene for 48 hours after your symptoms have stopped to avoid passing the virus to other people.

Who is at risk of viral gastroenteritis?

Viral gastroenteritis can affect people of all ages, although young children and the elderly and people with reduced immune systems are most at risk of severe disease.

How is viral gastroenteritis prevented?

Wash your hands thoroughly with soap and running water for at least 20 seconds, and dry them with a clean towel:

• after using the toilet
• after changing nappies
• before eating or preparing food

How is viral gastroenteritis diagnosed?

A doctor will usually diagnose a person with gastro based on the person's symptoms. If there are a high number of cases in one place a doctor will test samples of faeces.

How is viral gastroenteritis treated?

There is no specific treatment for viral gastroenteritis. Most people will recover with rest and drinking a lot of fluid.

If you have gastro:

• rest at home and do not go to work. Children should not attend childcare or school until 48 hours after they no longer have symptoms (diarrhoea and vomiting).
• do not prepare food for others or care for patients, children, or elderly people. These precautions should continue until 48 hours after diarrhoea or vomiting stops. This includes people who prepare food in the home or work in the food industry.
• wash hands thoroughly with soap and running water for 20 seconds after using the toilet.
• drink plenty of clear fluids, such as water, or for example juice or soft drink diluted 1 part to 4 parts water, to prevent dehydration. Avoid undiluted fruit juice and soft drinks as they may increase dehydration and diarrhoea. Rehydration drinks that replace fluids and salts are available from chemists.
  
• In severe cases of dehydration, fluids may need to be administered through a needle or tube by a doctor.

If you are caring for someone with viral gastroenteritis:

• wash hands thoroughly with soap and running water for 20 seconds after any contact with the sick person.
• clean soiled surfaces and clothing to reduce the virus spreading further.
• when cleaning up vomit or faeces (poo):
  
• wear gloves
• wash your hands with soap and running water for 10 seconds after gloves are removed and disposed
• use disposable paper towels or rags to remove any solid material and seal them in a plastic bag before placing in the rubbish bin
• clean any soiled object or surface with hot water and detergent and allow to dry thoroughly
• wear a mask.

What is the public health response?

Outbreaks of gastroenteritis increase in winter and are common within families and group settings including nursing homes, hospitals, childcare centres, and schools. Doctors and hospitals are required to notify their local public health unit when there are two or more cases of gastro that are linked.

Public health units are able to:

• advise on how to identify an outbreak
• advise on how to control the outbreak
• help investigate outbreaks to determine the source and mode of transmission
• advise on the exclusion of people with viral gastro from work, school or other public gatherings.

Further information

• Norovirus fact sheet
• Controlling outbreaks fact sheet
• Guidelines for the public health management of gastroenteritis outbreaks due to norovirus
  
• How to look after children with gastroenteritis
  
• Hospital Gastro Pack
• Gastro Info Kit for Aged Care Facilities
• Petting zoos and personal hygiene fact sheet

For further information call your local Public Health Unit on 1300 066 055.