What is the Norwalk Virus?

Norwalk virus is also called small round structure virus. Intestinal diseases caused by Norwalk virus are mild and transient. Common conditions can include nausea, vomiting, diarrhea, and abdominal cramps. According to the literature, Norwalk virus is a common pathogen in intestinal infectious diseases caused by viruses. Intestinal infectious diseases caused by the disease are more common in winter.

Norwalk virus

Norwalk virus is about 27nm in size. It is a parvovirus containing DNA. It is the main cause of epidemic gastroenteritis in developed countries. The disease can occur throughout the year, more in autumn and winter, more common in children 1 to 10 years old. It often occurs in schools, nurseries, recreational groups, military camps, or homes. Raw aquatic animals, such as sea shellfish and oysters, are the main route of infection with the virus and may also be transmitted through the respiratory tract. 55% to 90% of adults have antibodies against Norwalk virus, and about 6% of diarrhea among tourists is caused by Norwalk virus.

Norwalk virus overview

In January 2010, there was an outbreak of Norwalk virus in the United Kingdom. It is estimated that as many as 500,000 people were infected within a week. As a result, more than 140 hospital wards were forced to be closed and disinfected on the weekend, and many non-emergency surgeries and prohibition of visits were to be cancelled. To prevent the spread of epidemic tide. ^[1]

Norwalk virus transmission

Humans are the only known hosts. Food and water contaminated with feces are the main mediators of transmission. Other transmission channels include:

1. Have close contact with infected patients;

2. Direct contact with contaminated objects and airborne;

3. Eating or drinking food or water contaminated by the virus;

4. Contact the patient's vomit or feces;

5. Touch contaminated items; or spread by air.

Norwalk virus contamination source

Norwalk virus food contamination

Because Norwalk virus can exist in sewage, if the shellfish grows in the sewage area or the nearby waters, or the vegetables are irrigated by sewage, the chance of being infected by the virus will be greatly increased. Eating raw or undercooked foods (including shellfish, salads, and raw vegetables) is more susceptible to the Norwalk virus. In Hong Kong, consumption of oysters has been linked to cases of food poisoning caused by the Norwalk virus. In other countries, ice cubes, salads, raw vegetables and shellfish have also been identified as the main vectors of food poisoning by Norwalk virus. Anyone who eats contaminated food has the same chance of contracting Norwalk virus.

Norwalk virus environmental infection

Strict adherence to food, personal and environmental hygiene codes is the main method of preventing Norwalk virus infection.

Norwalk virus recommendations

Norwalk virus advice to citizens

You should patronize licensed and good restaurants, especially when choosing to eat high-risk foods such as oysters.

All food (especially shellfish) should be cooked thoroughly before eating.

If vegetables are to be eaten raw or used as salad ingredients, they must be thoroughly washed and packed with food, and stored in a freezer at 4C or below.

Wash hands thoroughly with soap and hot water after using the toilet, before handling food and eating.

Citizens should drink sterilized milk and bottled drinks without ice if they suspect that the water source has been contaminated. They should also eat thoroughly cooked food while hot.

Norwalk virus advice to manufacturers

Food materials (especially shellfish) should be purchased from reputable and approved suppliers.

The importer should first apply for a health certificate from the health authority in the place of origin to prove that the imported food products are suitable for human consumption.

Food handlers should not handle or contact food if they have symptoms such as vomiting or diarrhea. Do not handle food until you have recovered for at least two days.

Norwalk virus symptoms

Symptoms of this disease include nausea, vomiting, diarrhea, abdominal pain, mild fever, and discomfort. Symptoms usually last for 24 to 48 hours and resolve on their own. Norwalk-like viruses often cause food poisoning or gastroenteritis, and are likely to cause illness outbreaks in homes and schools. In addition, people of all age groups have the opportunity to contract the disease.

Norwalk virus latency

The incubation period is usually 24 to 48 hours.

Norwalk virus handling and prevention

Patients need to replenish lost water. Antibiotics have no effect on patients.

Maintain good personal, food and environmental hygiene.

Wash hands thoroughly before handling food or after eating, as well as afterwards, and after handling vomitus or feces.

Wear gloves when cleaning up vomitus and faeces, and wash hands afterwards.

Immediately wash and disinfect contaminated clothing and objects with diluted household bleach (5.85%) (1 part bleach plus 49 parts water).

Do not go to work if you are dealing with food or nursing staff if you have vomiting or diarrhea, and you should seek medical advice as soon as possible.

There is no vaccine to prevent Norwalk-like infections.