Case 43: Rotavirus Flashcards
what’s another name for rotavirus?
infantile gastroenteritis
are rotaviruses RNA or DNA viruses?
nonenveloped RNA viruses
what family are rotaviruses?
Reoviridae
what is the structure of the capsid?
2 concentric shells
what is the shape of the virion particle?
double-shelled particles shaped like wheels with short spokes on an outer rim
virions have an icosahedral structure and lack an envelope
how many types of rotavirus are there?
3 major subgroups : A, B, C
9 serotypes
what type of genome do rotaviruses have?
they have a segmented genome with 11 segments of a double-stranded RNA genome
however, gene reassortment has played no role in genetic diversity of rotaviruses,
and the virus strains have remained stable
do rotaviruses grow well in cell cultures?
eh not really, enteric viral agents don’t normally
what is used to diagnose rotavirus?
rotavirus and other enteric viral agents grow poorly in cell culture
so instead, assays that detect viral antigen in stool
specimens have become the most widely used method of diagnosis
rotavirus antigen can be detected in the stool using enzyme immunoassay
what type of virus is responsible for the majority of the cases of gastroenteritis?
enteric viruses
what are the leading viral pathogens?
rotaviruses and noroviruses
followed by enteric
adenoviruses, astroviruses, and coronaviruses
what is the major clinical effect of rotaviruses?
rotaviruses are the single most
important cause of severe dehydrating diarrhea in infants and children younger
than 3 years of age worldwide
they are also responsible for up to 10% of all diarrheal episodes among children younger than 5 years in the US
during what season are rotaviruses most prominent?
rotavirus
infection has a seasonal distribution in the United States, with transmission occurring
during the winter months
how are rotaviruses transmitted?
fecal-oral route
rotaviruses are shed in high concentrations in the stools of
infected children and are transmitted by the fecal-oral route, both through close
person-to-person contact and through fomites
what are fomites?
objects or materials which are likely to carry infection, such as clothes, utensils, and furniture
how can rotaviruses negaitvely effect elderly?
elderly individuals who are
immunocompromised or who have undergone hematopoietic or solid organ
transplantation experience severe, prolonged, and sometimes fatal rotavirus diarrhea
what is the pathogenesis of the rotavirus?
after fecal-oral acquisition, the virus infects the mature villus tip cells of the small intestine
viral invasion of the epithelial cells of the small intestine results in
destruction of the mature absorptive cells
damaged cells on villi are replaced by
immature crypt cells that cannot absorb carbohydrates or other nutrients
efficiently, resulting in osmotic diarrhea
the severity of rotaviral diarrhea is
proportional to the extent of mucosal damage in the small intestine
how do you treat rotavirus?
there is no specific antiviral agent for this disease
symptomatic care is directed at
supportive measures, with particular attention to the prevention of dehydration through
the use of intravenous hydration or oral rehydration therapy
how do you prevent rotavirus?
an oral live attenuated rhesus-based rotavirus vaccine-tetravalent was licensed in the
United States in 1998 for vaccination of infants – it was withdrawn a year later because
of reports of intussusception, a form of intestinal obstruction, as an uncommon but
serious side effect
adherence to hand washing and barrier methods are important for
preventing disease spread in day care and in the hospital setting
in view of the fecaloral
route of transmission, wastewater treatment and sanitation are important control
measures in the community
what are some of the hallmark features of rotavirus?
- little kids
- winter months
- vomiting, watery diarrhea, fever
- acute, sudden onset presentation
- dry mucous membranes
