Rotavirus

12 Key excerpts on "Rotavirus"

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  Molecular Detection of Human Viral Pathogens

  • Dongyou Liu(Author)
  • 2016(Publication Date)
  • CRC Press

    (Publisher)

  Rotavirus infects most children early in life and although the majority of first infections cause only mild diarrhea, 15–20% need treatment at a clinic, and 1–3% lead to dehydration that require hospi-talization [6]. 72.1.1 M ORPHOLOGY , G ENOME O RGANIZATION , C LASSIFICATION , E PIDEMIOLOGY , AND B IOLOGY Rotavirus morphology. Rotavirus is classified as a genus in the Reoviridae family. Complete viral particle is a large nonenveloped virus, approximately 70 nm in diameter, con-sisting of three concentric icosahedral capsid structures. The viral genome, comprising 11 segments of double-stranded RNA (dsRNA), is packaged entirely within the innermost core layer [4]. The innermost layer is formed by the VP2 protein, known as RNA binding protein. The transcription enzymes VP1 (viral RNA polymerase) and VP3 (guanylyl-transferase) are attached as a heterodimeric complex to the inside of the VP2 innermost surface protein. The middle layer is formed exclusively by the most abundant protein of the virus, VP6, which defines group and subgroup (SG) specificities. The outermost viral capsid is primarily com-posed of two proteins, VP4 and VP7. The VP4 contributes to the spikes that extend from the surface of the viral parti-cle, while VP7 forms the smooth outer surface of the virion [7,8]. Both of these proteins have essential functions in the replication cycle of the viruses, including receptor binding and cell penetration and thus represent important targets of neutralizing antibodies [4,9]. Rotavirus infectivity could be significantly increased by trypsin treatment of the viral par-ticles. This proteolytic enzyme treatment results in specific cleavage of VP4 (776 amino acids) into two polypeptides, VP8 (amino acids 1–231) and VP5 (amino acids 248–776), and appears to play an important role in cellular attachment and penetration of the virus into the cells [10]. Rotavirus genome organization and proteins. The Rotavirus genome consists of 11 segments of dsRNA [4].

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  Human Viruses in Water

  Perspectives in Medical Virology

  • Albert Bosch(Author)
  • 2007(Publication Date)
  • Elsevier Science

    (Publisher)

  Among children younger than 2 years, nearly half of all the cases of diarrhea requiring admission into a hospital can be attributed to Rotavirus infection. Rotavirus is increasingly recognized as a cause of infectious diarrhea in adults as well as children ( Anderson and Weber, 2004 ). Rotaviruses are a genus of the Reoviridae family and possess a genome of 11 segments of double-stranded RNA. The genome codes for six structural viral proteins (VPs; termed VP1, VP2, VP3, VP4, VP6 and VP7) and six non-structural proteins (NSPs; termed NSP1–NSP6) ( Estes, 2001 ). Rotaviruses are triple-layered icosahedral particles approximately 75 nm in diameter with the RNA segments residing within the core. The core is surrounded by an inner capsid, composed mostly of VP6, the primary group antigen, and includes the epitope detected by most common diagnostic assays. Seven distinct groups of Rotavirus (named A–G) have been shown to infect various animal species. Of these, only groups A, B and C have been reported as human pathogens ( Estes, 2001 ). Group A is the primary path-ogen worldwide and is the group detected by commercially available assays. Additional subgroups and serotypes can be identified by further characterization of VP4, VP6 and VP7 antigens ( Kapikian et al., 2001 ). Group B appears to be limited to causing epidemic infection is Asia and the Indian subcontinent, whereas group C Rotavirus causes endemic infections that frequently go unrec-ognized ( Kapikian et al., 2001 ). Protective immunity to Rotavirus is of short duration and reinfection occurs throughout life due to the great number of serotypes ( Estes, 2001 ). Rotaviruses are shed in extremely high numbers (up to 10 10 g –1 ) from the feces of infected individuals and can persist in the environment for extended periods of time ( Carter, 2005 ) resulting in the potential for recreational and drinking water contamination.

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  Mucosal Immunology

  • Jiri Mestecky, Michael E. Lamm, Pearay L. Ogra, Warren Strober, John Bienenstock, Jerry R. McGhee, Lloyd Mayer(Authors)
  • 2005(Publication Date)
  • Academic Press

    (Publisher)

  This chapter reviews three enteric viral infections of humans in which the primary or sole site of viral replication and the underlying mechanisms of pathogenesis result from local infections in the cells of the gastrointestinal tract. Rotaviruses, human caliciviruses, and astroviruses are considered, with emphasis on Rotaviruses because of their significant clinical impact in children and because Rotavirus vaccines are in phase III trials and the furthest toward licensure. Immunity for these enteric viruses is complex, but studies on immunization and vaccine development involving these viruses are clearly useful as models for probing virus–cell interactions in the gastrointestinal tract and for learning how to induce mucosal immunity to prevent local infections.

  RotavirusES

  Introduction

  Rotaviruses are the single most important cause of severe infantile gastroenteritis. In the United States alone, these viruses are estimated to cause 50,000 to 100,000 hospitalizations in young children each year and approximately 20 to 40 deaths. On a world scale, Rotaviruses are estimated to be responsible for nearly 1 million deaths annually (

  Kapikian et al., 2001

  ). Cost estimates for hospitalizations due to Rotavirus infections in the United States are greater than $300 million each year, and this does not account for the cost of doctors’ visits and home care associated with 2 million less severe Rotavirus illnesses. For these reasons, Rotaviruses have received a high priority as a target for vaccine development.

  Rotavirus transmission occurs by the fecal–oral route, providing a highly efficient mechanism for universal exposure that has circumvented differences in regional and national cultural practices and public health standards. The symptoms associated with Rotavirus disease are typically diarrhea and vomiting, accompanied by fever, nausea, anorexia, cramping, and malaise, which can be mild and of short duration or produce severe dehydration. Severe disease occurs primarily in young children, most commonly between 6 and 24 months of age. Approximately 90% of children in both developed and developing countries experience a Rotavirus infection by 3 years of age. Rotavirus infection normally provides short-term protection and immunity against subsequent severe illnesses but does not provide life-long immunity, and there are numerous reports of sequential illnesses. Neonates can also experience Rotavirus infections, and these occur endemically in some settings but are typically asymptomatic. These neonatal infections have been reported to reduce the morbidity associated with a subsequent Rotavirus infection (

  Bishop et al., 1983

  ;

  Bhan et al., 1993

  ). Rotavirus illnesses also occur in adults and the elderly, but the symptoms generally have been believed to be mild. A recent study conducted in Japan, however, suggests that Rotaviruses are a major cause of hospitalization of adults due to acute diarrhea (

  Nakajima et al.,

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  Zoonoses: Viral, Rickettsial and Prion Diseases

  • Garg, Sudhi Ranjan(Authors)
  • 2021(Publication Date)
  • Daya Publishing House

    (Publisher)

  Rotavirus is non-enveloped virus of Reoviridae family consisting of 11 segments of double stranded RNA of molecular weights ranging from 2.0x10 5 to 2.2x10 6 , that codes six structural proteins (VP1, VP2, VP3, VP4, VP6 and VP7) and six non-structural proteins (NSP1 to NSP6). Each gene codes for one protein, except gene 11, which codes for two. The virus particles are about 76.5 nm in diameter with icosahedral symmetry. The virus is composed of three concentric shells that enclose 11 gene segments. The outermost shell contains two important proteins: VP7 or G-protein, and VP4 or P-protein. VP7 and VP4 define the serotype of the virus This ebook is exclusively for this university only. Cannot be resold/distributed. and induce neutralizing antibody that is probably involved in immune protection. Due to antigenic and genomic diversity, Rotavirus has been classified into seven groups as A, B, C, D, E, F and G. Of these seven, only group A, B and C are known to infect humans while other groups have been found in animals. Group A Rotaviruses are considered to be important zoonotic viral agents associated with diarrhoea in children and young animals worldwide. Group A Rotaviruses have been characterized as possessing 15 G and 21 P genotypes. However, 23 distinct G genotypes and 31 P genotypes have been identified till date (Mukherjee et al. 2010). Genotype P[27] was recently identified from porcine origin (Khamrin et al. 2008). Rotavirus is very stable and may remain viable in the environment for weeks or months if not disinfected. Geographical Distribution and Epidemiology Amongst all Rotavirus types, Rotavirus A is endemic worldwide, which accounts for more than 90 per cent gastroenteritis in humans. There is a tremendous amount of global illness and deaths caused by Rotavirus disease in children.

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  Veterinary Public Health: New Trends

  • Rahman, H(Authors)
  • 2021(Publication Date)
  • Biotech

    (Publisher)

  GLOBAL PREVALENCE OF Rotavirus AND NOROVIRUS AND THEIR GENOTYPIC DIVERSITY IN INDIA Z.B. Dubal, K.N. Bhilegaonkar and Shriya Rawat Diarrhoeal diseases are major cause of childhood morbidity and mortality all over the world. Many pathogenic bacteria like E. coli , Salmonella , Shigella etc. and enteric viruses like Rotavirus, norovirus, astrovirus, enterovirus etc. are responsible for gastroenteritis. Of the enteric viruses, Rotavirus and norovirus have been recognized as the most common cause of severe gastroenteritis in a wide variety of animal species worldwide. In low income countries, diarrhoea is the third most common cause of death with 17% deaths is under 5 yrs age group (WHO, 2004). In India, annually 18.6 million children under 5 yrs are affected with nearly 3,86,000 deaths. The two enteric viruses i.e. Rotavirus and norovirus, though contributing a major chunk of these diarrhoeagenic agents, are neglected especially in India. Both are RNA viruses with Rotavirus (family Reoviridae) possessing 11 segments of dsRNA, while norovirus (family Caliciviridae) has ssRNA as the genetic material. Rotavirus infection is mainly encountered in very young animals and children below five years of age, whereas norovirus affects all age groups and is usually associated with food-borne outbreaks in cafeterias, hospitals, ships etc. Rotavirus AND NOROVIRUS Rotavirus has a distinct wheel like appearance by negative staining electron microscopy (EM) and thus the name rota which in Latin means “wheel”. The virus particles are about 70 nm in diameter and posses icosahedral symmetry. They have triple layer capsid, the innermost layer of which, the core, contains the viral genome. This genome consisting of 11 This ebook is exclusively for this university only. Cannot be resold/distributed. segments of dsRNA that code for 6 structural proteins (VP1, VP2, VP3, VP4, VP6 and VP7), and 6 non-structural proteins (NSP1-NSP6). However, gene segment 11 encoding both NSP5 and NSP6 proteins.

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  Clinical Virology

  • Douglas D. Richman, Richard J. Whitley, Frederick G. Hayden, Douglas D. Richman, Richard J. Whitley, Frederick G. Hayden(Authors)
  • 2016(Publication Date)
  • ASM Press

    (Publisher)

  6 ).

  FIGURE 1    Map of the world showing Rotavirus mortality in 2008, reproduced with permission from (5 ).

  Rotaviruses do not account for a substantial number of deaths in developed countries, probably because of efficient and widespread access to rehydration and other supportive measures. Moreover, with the advent of Rotavirus vaccines the impact of this pathogen has diminished in recent years in most developed countries. For example, in the United States detection of Rotaviruses and costs for associated treatment have drastically diminished after vaccine introduction (7 , 8 ). Although Rotavirus was still identified in 12% of children with acute gastroenteritis in 2009 and 2010, during the same period norovirus replaced Rotavirus as the leading cause of medically attended acute gastroenteritis in U.S. children (9 ). A similar situation may be occurring in some developing countries, as exemplified in Nicaragua where the epidemiology of diarrhea is changing (10 ).

  VIROLOGY

  Classification

  Rotaviruses belong to the Reoviridae family of icosahedral, nonenveloped, segmented double-stranded (ds) RNA viruses. Rotaviruses are classified into five groups (A through E) depending on the presence of cross-reactive antigenic epitopes primarily located on the internal structural protein VP6. Among these, Group A Rotaviruses (RVA) are the most frequent pathogens of humans, and groups D and E have been found only in nonhuman animals. Unless otherwise noted, this chapter will address only RVA. Group B Rotaviruses (RVB) are sporadic pathogens of animals but have been implicated in several large outbreaks of adult diarrhea in China in the 1980s and less frequently in the 1990s (11 ). More recently, they have been identified in children and adults with diarrhea in India and Bangladesh (12 , 13 ). Group C Rotaviruses (RVC) are primarily veterinary pathogens but have been reported to be sporadically associated with diarrhea in children. The seroprevalence of these Rotaviruses is relatively high in humans, especially those living in rural areas, suggesting transmission from animals to humans (14 ). However, in some countries such as India, prevalence of antibodies against RVC is the same in urban and rural populations (15

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  Manual of Molecular and Clinical Laboratory Immunology

  • Barbara Detrick, John L. Schmitz, Robert G. Hamilton, Barbara Detrick, John L. Schmitz, Robert G. Hamilton, Barbara Detrick, Robert G. Hamilton, John L. Schmitz(Authors)
  • 2016(Publication Date)
  • ASM Press

    (Publisher)

  Table 1 . Although the field of diagnostic virology is advancing rapidly, with multipathogen formats gaining widespread use, the techniques described here for individual viral pathogens will continue to provide important information on the epidemiology, natural history, and evolution of these viruses.

  TABLE 1 Common viral agents of gastroenteritis identified in stoola

  RotavirusES

  Overview

  Rotaviruses

  are a major cause of acute gastroenteritis in humans and animals. They have a double-stranded RNA genome divided into 11 segments that encode the viral proteins: 6 structural proteins (VP1 to VP4, VP6, and VP7) and at least 5 nonstructural proteins (NSP1 to NSP5) (

  Fig. 1A ) (1 ). The Rotavirus segmented genome is enclosed within a triple-layered protein icosahedral capsid, in which the inner capsid is formed by the VP2, the intermediate capsid by the VP6, and the outer capsid by the VP7 and VP4 (Fig. 1A ). Based on differences within the VP6 protein, Rotaviruses can be divided into nine groups (A to I) (2 ), with group A Rotavirus (RVA) the most prevalent (> 99% of the isolates) in humans (1 ).

  FIGURE 1 Rotavirus genome and genotype distribution. (A) Representation of Rotavirus virion, proteins, and double-stranded RNA gene segments. Proteins are color coded, and genes used for typing are highlighted with corresponding colors. The Rotavirus virion was modeled using crystal coordinates from VP2, VP6, VP7, and VP4 proteins (PDBs: 3IYU and 3N09) and visualized in Chimera. (B) Global incidence of the most predominant Rotavirus strains in humans according to genotype. Numbers represent the percentage of total strains included (n = 16,474). (Adapted from reference 5 .)

  Antigenic and genetic differences within the two outermost proteins, VP4 and VP7, have been used to classify RVA by a dual nomenclature system into P and G types, respectively. Currently, 37 P types and 27 G types have been described in different animal species (3 , 4 ). Surveillance of RVA in humans has shown that five strains (G1P[8], G2P[4], G3P[8], G4P[8], and G9P[8]) are the most common (Fig. 1B ), but temporal and geographic changes in strain prevalence as well as the emergence of strains bearing unusual G types (e.g., G8, G10, or G12) have been observed (1 , 5 ). Based on full-genome sequencing and differences within each of the 11 segments, a comprehensive classification system has been established for RVA. This system recognizes the genomic characteristics of RVA from different species and defines the presence of three major genomic constellations, with two prevalent in humans (WA-like and DS1-like) and one in animals (AU1-like) (6

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  Antigenic Variation

  • Alister G. Craig, Artur Scherf(Authors)
  • 2003(Publication Date)
  • Academic Press

    (Publisher)

  VIRUS CLASSIFICATION AND STRUCTURE Rotavirus is a medium-sized (70–80 nm), unenveloped, round virus with a characteristic wheel-shaped morphology (Figure 5.1). ( Rota is Latin for a wheel.) Rotavirus is a genus within the family Reoviridae , which contains eight separate genera. Its genome consists of eleven segments of double- Rotavirus stranded RNA, which range in size from 0.6 to 3.3 kilobase pairs (kbp). Each segment encodes one or more polypeptides (Table 5.1). The polypeptides produced are either involved in viral replication and not found in the mature virion (non-structural proteins: NSP) or structural proteins making up the virus particles (virus proteins: VP). The mature virion has a trilayered structure (Figure 5.2). The inner layer consists of the 11 dsRNA segments surrounded by VP1, VP2 and VP3. The middle layer, also referred to as the inner capsid, is composed entirely of VP6, and the outer layer or capsid is made up from two proteins, VP7 and VP4. The latter is cleaved by proteolysis to VP5* and VP8*. The mature virion has 60 spikes or knobs extending 120Å from the surface (Estes, 1996). The virion has icosahedral symmetry, with 132 surface capsomers and a triangulation number of T13. There are also 132 large channels that traverse both the inner and the outer capsids. 85 Figure 5.1 Negative stain electron micrograph showing Rotavirus particles in a stool sample (Bar = 100 nm). Antigenic Variation ANTIGENS AND EPIDEMIOLOGICAL MARKERS Rotavirus can be subdivided into a puzzling array of group, subgroup, serotype, genotype, electropherotype and genogroup. Group Thus far Rotaviruses are split into seven groups based on epitopes on the inner capsid protein VP6 (Table 5.2).

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  Human Emerging and Re-emerging Infections

  • Sunit Kumar Singh(Author)
  • 2015(Publication Date)
  • Wiley-Blackwell

    (Publisher)

  Chapter 12 Pathogenesis of Rotavirus in Humans Carlos Fernando Narváez1 , Martha C. Mesa2 , Alfonso Barreto2 , Luz-Stella Rodríguez3 , and Juana Angel3

  1 Facultad de Salud, Programa de Medicina, Universidad Surcolombiana, Neiva, Colombia

  2 Departamento de Microbiología, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá, Colombia

  3 Instituto de Genética Humana, Facultad de Medicina, Pontificia Universidad Javeriana, Bogotá, Colombia

  12.1 Introduction

  12.1.1 Morphology

  In Latin, rota means “wheel” and this is the shape of a Rotavirus (RV), as seen by electron microscopy. The non-enveloped, viral particles have a diameter of approximately 100 nm with an icosahedral structure T = 13l. It is formed by three concentric protein layers, surrounding the viral genome made up of 11 segments of double-stranded RNA (dsRNA), which code for 6 viral structural proteins (VPs) and 6 non-structural proteins (NSPs) (see Figure 12.1 ). Each RNA segment codes for only one protein, except segment 11, which codes for NSP5 and NSP6 in some viral strains (Greenberg and Estes, 2009). The viral core is made of 120 copies of VP2 containing the genome, VP3 (with guanylyltransferase and methyltransferase) and VP1 (RNA-dependent RNA polymerase) associated with each dsRNA segment. The viral genome packed in the core is approximately 0.7–3.3 kb in size. The intermediate layer is formed of 260 dimers of VP6, the most abundant VP. The viral particles formed by VP1, VP2, VP3, and VP6 are called double-layered particles (DLPs). The external and third viral layer is formed by trimers of VP7 (calcium binding glycoprotein) and a spike protein VP4, which interacts with the intermediate layer by binding VP6. Trimerization of VP7 is calcium dependent. All VPs have auto-assembling capacity to form the triple-layered particles (TLPs) (Trask et al., 2012).

  Fig. 12.1

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  Emerging and Reemerging Viral Pathogens

  Volume 1: Fundamental and Basic Virology Aspects of Human, Animal and Plant Pathogens

  • Moulay Mustapha Ennaji(Author)
  • 2019(Publication Date)
  • Academic Press

    (Publisher)

  Chapter 45

  Worldwide Emerging and Reemerging Rotavirus Genotypes: Genetic Variability and Interspecies Transmission in Health and Environment

  Rihab Bouseettine1 , Najwa Hassou1 , A. Hatib1 , B. Berradi2 , Hlima Bessi1 and Moulay Mustapha Ennaji1 ,    

  1 Laboratory of Virology, Microbiology, Quality, Biotechnologies/Eco-Toxicology and Biodiversity, Faculty of Sciences and Techniques, Mohammedia, University Hassan II of Casablanca, Casablanca, Morroco

  ,    

  2 Laboratory of Cellular and Molecular Pathologies, Faculty of Medicine and Pharmacy, University Hassan II of Casablanca, Casablanca, Morocco

  Abstract

  Rotavirus (RV) is the causative agent of infectious diarrhea, severe in children in the world. It is a double-stranded ribonucleic acid virus belonging to the family Reoviridae (RV). Almost all the children in the world are infected by the RV at least once by the age of 5 years.

  This virus has a short incubation period of not exceeding 3 days. It is known by its transmission from person to person by the fecal–oral route. In developing countries the RV can also be transmitted by water contaminated by fecal materials. It is also suspected that the RV can spread from one child to another via the contamination by the infected surfaces.

  The genus Rotavirus belongs to the family Reoviridae. It is composed of seven serogroups, RV A–G, including RV A–C, that infect humans, mainly the Group A.

  To date, 15 G (glycoprotein) and 27 P (protease sensible) genotypes have been described. Studies of RV strains have demonstrated that the genes G1–G4 are the most common circulating G types. In the 1900s a new genotype, G9, appeared in 1983 and is now quite known worldwide. Several researchers have found a novel G12 RV. This gene presents a high prevalence due to its association with multiple VP4 genotypes. In addition, several other RV strains have demonstrated regional predominance. G5 RVs, previously found only in pigs and horses, were detected in Brazilian children in 1983 and have since been regularly reported from Brazil at a high incidence. Similarly, G8 RVs have been detected all over the African continent, especially in Malawi.

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  Vaccines for Biodefense and Emerging and Neglected Diseases

  • Alan D.T. Barrett, Lawrence R. Stanberry(Authors)
  • 2009(Publication Date)
  • Academic Press

    (Publisher)

  1974 ). Within a short time other investigators confirmed the association between the presence of Rotavirus in feces and acute gastroenteritis.

  In addition to their distinctive morphologic features, human Rotaviruses along with their animal counterparts, share a group antigen (Kapikian et al., 1976 ; Woode et al., 1976 ) and are classified as members of the Rotavirus genus within the Reoviridae family (Matthews, 1979 ). In 1980, particles that were morphologically indistinguishable from established Rotavirus strains but lacked the common group antigen were discovered in pigs (Bridger, 1980 ; Saif et al., 1980 ). This finding led to the identification of Rotaviruses belonging to six additional groups (B–G) based on common group antigens, with the original Rotavirus strains classified as group A (Saif and Jiang, 1994 ). Only groups A–C have been associated with human diseases, and most known cases of Rotavirus gastroenteritis are caused by group A strains. Although, there have been large outbreaks reported in China and Japan associated with nongroup A strains, particularly among adults (Hung, 1988 ; Kuzuya et al., 1998 ; Matsumoto et al., 1989 ), group A Rotaviruses are the strains to which vaccine development has been directed.

  Properties of the Virus

  Rotavirus is a double-stranded RNA virus. The genome segments of Rotavirus can be extracted from viral particles and separated by polyacrylamide gel electrophoresis into 11 bands visualized by ethidium bromide or silver staining as shown in Fig. 35.2 . Each Rotavirus strain has a characteristic RNA profile or electropherotype, a property that has been used extensively in epidemiologic studies of these viruses. The characteristic RNA electrophoretic pattern of group A Rotaviruses consists of four size classes containing segments 1–4, 5 and 6, 7–9, and 10 and 11 (Kapikian et al., 2001 ). A short pattern is seen when the segment 11 runs slower than segment 10. RNA segments of strains belonging to less well characterized Rotavirus groups (i.e., groups B–G) also can be separated into four size classes, but the distribution of segments within these classes differs from group to group (Saif, 1990

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  Vaccines

  New Approaches to Immunological Problems

  • Ronald W. Ellis(Author)
  • 2014(Publication Date)
  • Butterworth-Heinemann

    (Publisher)

  258 Rotavirus Vaccines portant impact in developed countries also, because the relative proportion of diarrheal cases attributed to Rotavirus is greater than that of all other agents, and the disease represents a heavy burden on health services. For instance, in a prospective study in Virginia, infection with Rotavirus oc-curred in 51% of participating families over a 29-month period. The inci-dence of gastroenteritis was 40 per 100 person years in the 12- to 23-month age group, and 12 per 100 and 13 per 100 person years in the 6- to 12- and 24-to 35-month age groups, respectively (Rodriguez et al. 1987). It was estimated from this study that about 3 million Rotavirus diarrhea cases occur yearly in the USA in children under 5 years of age, resulting in about 25,000 hospitalizations. The cost of treating such illnesses was estimated at over $115 million per year (Institute of Medicine 1985). Thus, although Rotavirus illness may not often lead to death in the USA it is nevertheless a common cause of morbidity and imposes an important burden on health services. 11.2 ASPECTS OF Rotavirus BIOLOGY RELEVANT TO VACCINE DEVELOPMENT 11.2.1 The Natural History of Rotavirus Infection Infection with Rotavirus leads to induction of specific secretory intestinal immunoglobulin A (IgA). Experiments in lambs, calves, and piglets showed that antibody in the intestinal lumen rather than circulating antibody was required for preventing Rotavirus diarrhea (Snodgrass and Wells 1976). Co-lostrum-deprived newborn lambs were protected against diarrhea if they were fed colostrum or serum that contained Rotavirus antibody prior to Rotavirus challenge. In contrast, serum antibody to Rotavirus failed to induce protection against Rotavirus challenge. It should be noted, however, that following intestinal infection, IgG, IgM, and IgA serum Rotavirus antibodies also develop and appear to be associated with resistance to Rotavirus illness or infection (Hjelt et al. 1986).

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