A Short Note On The Common Foodborne Viruses

Each and everyday, millions of humans spread infection without realizing it. A simple handshake and a nervous finger bite can lead in to something that can have great effect on your health. Norovirus or acute gastroenteritis, commonly known as Norwalk virus, is one of the most common sources of stomach infections. Norwalk is extremely contagious and can often be found in long term care facilities. The virus can be found in the stool and vomit of the infected person. To the majority of the population, Norwalk is nothing more than the everyday stomach flu and is usually cured without treatment. Although, there are exceptions to the young, the elderly, and people with a disease as they do not have as strong immune systems as the average adult.

The prototype of norovirus was identified in 1968 by electron microscopy as a cause of Gastroenteritis in Norwalk, Ohio. Human noroviruses are a major cause of Epidemic Gastroenteritis, and Epidemic Gastroenteritis is a major cause of foodborne illness. Outbreaks occur throughout the year, but it is most common in the winter. Causes 19-21 million cases of acute gastroenteritis, and contributes to 56,000-71,000 hospitalizations and 570-800 deaths, mostly among young children and older adults. Responsible for 58% of domestically-acquired foodborne illnesses, and about 50% of foodborne disease outbreaks due to known agents.

Norovirus is the most common cause of gastroenteritis. Infection is characterized by diarrhea, vomiting, and stomach pain, and fever or headaches may also occur. This usually develops 12 to 48 hours after being exposed. Individuals with norovirus may vomit and have diarrhea many times a day, leading to extreme dehydration, especially in young children, older adults, and people with other illnesses. The recovery typically occurs within 1 to 3 days.

Norovirus and Salmonella are the two most common pathogens, resulting in the most hospitalizations and deaths. Norovirus is a pathogen that infects the stomach and intestines by causing inflammation. Symptoms of norovirus include; nausea/vomiting, diarrhea and stomach pain leading to dehydration causing one to urinate more frequently and feel dizzy while standing up. In order to avoid contracting the Norovirus, the CDC recommends thoroughly washing fruits, vegetables and cooking seafood to appropriate temperatures, which can survive up to 140 degrees Fahrenheit (https://www.cdc.gov/norovirus/preventing-infection.html). Salmonella affects the gastrointestinal tract when bacteria is swallowed, mainly coming from raw food products; eggs,

The influenza virus is part of the Orthomyxoviridae family and is spherical in shape with many spike-like projections of glycoproteins HA. The viral core is composed of eight negative-sense, single

Noroviruses (NoV) are important human pathogens and a major public health threat. Noroviruses are non-enveloped, single-stranded, positive sense RNA viruses that cause acute gastroenteritis in humans (1-4). Noroviruses have been referred to as ‘cruise ship viruses’ from well-publicized cruise ship outbreaks although these outbreaks account for less than 1% of all outbreaks worldwide (5). The symptoms and illness associated with Norovirus infections is often referred to as ‘stomach flu’, despite little resemblance to the influenza virus. Noroviruses are responsible for 21 million infections and over 70,000 hospitalizations annually in the USA, and account for 10-15% of severe cases of gastroenteritis in children less than 5 years old (6). In

Viruses affect us in our everyday life and they have become something that is not an abnormal phenomenon or a fatal occurrence like it was in olden times. (Alic and Longe , 2015) Likewise, the viruses that affect us have much impact of what the actual disease is. Norovirus being an example of a virus that affects our daily lives and can be fatal. (Longe, 2015) This disease is highly contagious and is very often overlooked by the public eye, however it can have much impact on our daily lives and how we live. This virus can be seen throughout all of your lifetime and can affect anybody at any age, it is harder to treat as it can withstand high temperatures and can live in almost any environment making it difficult to damage and control. (Alic and Longe , 2015) Norovirus outbreaks are very common

Cytomegalovirus (CMV) is a double stranded DNA virus that causes no to mild flu-like symptoms in normal individuals. However, it can cause severe disease in immunocompromised patients. CMV is a major cause for birth defects. Infants who develop congenital CMV infection experience seizures, intellectual disability, muscle weakness, and hearing loss. According to the National CMV Foundation, 1 in every 150 babies are infected with CMV per year, making it one of the most common congenital viral infection in the United States. In previous studies, researchers found poliovirus can bind to the lipopolysaccharide of enteric bacteria. By doing so, the poliovirus enhances infectivity and association with the host cell. Inspired by these findings, our

The long filaments are 80 nm in diameter and either 800–1000 nanometers long. RNA is only 1% of the mass of the virus. The large virus structure is composed of three compartments the nucleocapsid, the matrix space and the envelope. The central core of each filovirus virion consists of the single RNA genomic molecule and its adherent nucleoproteins NP and VP30 (the nucleocapsid). They are linked by matrix proteins VP24 and VP40 to the inner surface of the lipid bilayer of the viral envelope, which is derived from the host cell. Trimeric spikes of the surface envelope glycoprotein are anchored in the bilayer. Two other proteins, VP35 and large protein (RNA-dependent RNA polymerase), are also present within the virion. The surface GP is coded by the GP gene, and is expressed in two molecular forms (GP1 and GP2) that are generated by an RNA editing mechanism; it has important roles in virus infection and pathogenesis, and its expression is tightly regulated during virus replication. It has been recently demonstrated that the level of GP1 and 2 expressions regulates the virus production and

Viruses come in different genomes and different forms however they all have a capsid where they maintain their genetic material. Viruses are classified into families that are distinguish based on their shape and form as well as they have names that are used for identification and is usually related to the type of disease they cause. Rotavirus is a member of the family Reoviridae that is nonenveloped segmented double stranded RNA and globally is the leading cause of severe diarrhea problems among infants and young children worldwide (1). Rotavirus developed in a wheel shaped virus that is surrounded by a triple layer coat composed of different structural proteins. The outer layer is composed of VP7 and VP4 that is cleaved by trypsin into two

As it is known to everyone, the influenza is a worldwide infectious disease and very familiar to those people who are living in small villages or in very big cities. The influenza or the flu as it usually referred is caused by RNA viruses which belong to Orthomyxoviridae family. These viruses affect mammals and birds as well. The influenza is typically transmitted through the air by sneezes or coughs creating virus containing aerosols. This is not the only way for influenza transmission but it could be also transmitted by nasal secretions or bird droppings if directly contact (Collier et al., 2006).

The incubation period is for an average of two days, implying that norovirus takes two days from the mouth to the small intestine to cause the adverse effect with biologically active dose. The illness is typically acute onset because extremely short-term, only minute dose of the exposure with usually one contact can cause the infection to humans indiscriminately. A specific fraction of the population such as elderly people, children and pregnant women are susceptible, due to the incomplete immunity, showing severe illness with extra symptoms such as dehydration and the fever, which indicates that the human body response may not be limited in the small intestine but extended to the entire body. Children are at risk of exposure because of the frequent non-dietary ingestion with random hand-to-mouth activities. (Atmar et al., 2008; Division of Viral Diseases, 2011; Hall, 2012)With a low infectious dose and high levels of shedding, a norovirus outbreak can occur in this environment, accompanied with the poor infrastructure destructed by the disaster and the weather in the affected area, therefore it is important to take public health

The most common cause of Gastroenteritis in the United States is triggered by the Norovirus with approximately 21 million cases per year, which contributes to nearly 800 deaths and 71,000-hospitalization annually.1 The virus not only afflict United States Citizens but, persons all over the world. Worldwide Norovirus accounts for 9 to 24% of all sporadic gastroenteritis.2 Norovirus is a very contagious virus that affects people of all ages, sexes, genders, and ethnicities, with the most adverse health effects for the elderly and the young. The most severe health affects occur in children under 5 years of age and adults over the age of 65, because they are considered immunocompromised.3 Recurrences often occurs because the virus is extremely diverse and lacks long-term immunity. Therefore, there are many ways in which a person can contract the virus, which includes drinking contaminated water or touching contaminated surfaces. In the case definition of norovirus, the afflicted persons experience issues with their intestines and stomach, or experience acute gastroenteritis; this is followed by severe vomiting and diarrhea.1

Lujo Hemorrhagic Fever is caused by a bi-segmented negative RNA virus that is one of the several viruses known to cause viral hemorrhagic fever. The Lujo virus is part of the Arenaviridae family, that consist of several viruses categorized into two primary groups. The Lujo virus is categorized in the “Old World” group, which signifies that the virus in question was discovered in the Eastern Hemisphere, specifically in Africa. The majority of the arenaviruses that are categorized in the “Old World” group do not cause severe illness, with the exception of a few including the Lassa and Lujo virus. As of 2012, the Lujo virus is classified as a select agent as it is distinguished to possess the potential to severely threaten the US public’s health and safety when the mortality rate and modes of transmission is taken into consideration.

The following is a literature review of the Norovirus. According to Prasad, Hardy, Dokland, Bella, Rossmann and Estes, Norovirus is classified as a virus belonging to the Caliciviridae family. The genus Norovirus has only one species known as the Norwalk Virus (NV) and a number of serotypes. These strains of Norovirus are classified genetically into five genogroups, namely GI, GII, GIII, GIV and GV. Only viruses in the GI and GII genotypes affect humans. Noroviruses under GI genotype include the Southampton Virus and the Norwalk Virus. Noroviruses under GII genotype include the Lordsdale Virus, Hawaii Virus, Mexico Virus, Bristol Virus and the Snow Mountain Virus. The rest of this paper covers the characteristics of the Norovirus, the diseases it causes, its diagnosis and treatment, its hosts and finally its prevalence in the United States.