Viral enteritis Flashcards
(13 cards)
describe viral gastroenteritis ?
Viral gastro-enteritis inflammation of the lining of the stomach, small intestine, large intestine
Several different viruses can cause viral gastro-enteritis cause millions of cause diarrhea each year
Anyone can get viral gastroenteritis but most people recover with any complication unless they become dehydrated
Viruses are up to 3/4 of the cause of infective diarrhea
Viral gastroenteritis the second most common viral illness after URTI
ROTAVIRUSES = IN CHILDREN AND INFANTS and most imp
viruses associated with gastro-enteritis ?
Major viruses :
Rotavirus
Enteric adenovriuses
Nonviruses –> norwalklike virus, calicviruses, astrovirus
MMinor viruses :
Coronaviruses
Parvoviruses
Pestiviruses
Toroviruses
describe rotavirus ?
Infect bowels causing SEVERE INFLAMMATION OF THE STOMACH AND BOWEL
SEVERE DIARRHEA AMONG INFANTS —> 6M TO 2 YEARS
HUMAN AND ANIMAL STRAINS
can affect adults but less severe illness
rota virus is a member of what?
Reoviridae family of viruses and CONTAIN :
double stranded RNA ( De segmented RNA )
Enclosed by double shelled outer layer ( CAPSID )
Rota = looks like a wheel
Similar to corona virus in shape but not pathogenicity
how does rota virus enter?
Mouth and replicate in epithelium of small intestines
SHORT INCUBATION PERIOD - 1-3 DAYS ( short )
GI symptoms resolve in 3 to 7 days and can last up to 6 days
What does rota virus lead to ?
Severe diarrhea
Dehydration
Electrolytes imbalance
children who are malnourished or weaker immune may have more or severe persistent disease
COMPLICATIONS LIKE DEHYDRATION CAN RESULT IN DEATH IN YOUNG CHILDREN
Characteristics of Rotavirus ?
Rota = wheel = WHEEL LIKE APPERANCE
70-75 mn round
NON EVELOPED VIRUS
Double RNA strands enclosing a RNA genome consists of 11 segments of RNA coding for 12 proteins
Nucleic acid is surrounded by TWO layers :
Intermediate layer consisting of major capsid protein VP6
Outer layer that contains attachment protein VP4 and VP7
its icosahedral symmetry
Rotaviruses are stable to heat 50c
3-9 ph range
can survive Lipid solvents such as ether and chloroform but they are inactivated by 95% etahonol and phenol ,chloride, heat above 100 and ph less than 3 ( so to kill it boil it or spoil it by alcohol )
Groups of rotaviruses?
Seven serological groups have been identified AG three of which A,B,C infect humans
Group A = subtypes 1,2,3,4 also infect humans and animals
Group B = Infect humans , pigs and rats (china )
Group C = Infect pigs ( occasionally man )
GROUP A = MOST COMMON
B= associated with china outbreak
C = sporadic cases of diarrhea in infants
how rota virus transmitted?
Fecal oral route primary ( USUALLY DIRECT CONTACT )
Ingestion of food water contamined
Highest rate of illness occurs among infant and children age 5 and under
Adults can get rota virus
DISINIFECTED USING ETHANOL FORMALIN
Sign and symptoms of rota virus ?
Inflammation of the stomach and intestines
SEVERE —> Diarrhea in infants and children ( WATTERRRYY DIARRHEAAA )
appear as watery , green , yellow but:
NO MUCUS AND BLOOD
FEVER
Vomiting , leading to dehydration , vomiting is usually of short duration and may occur before or after the onset of diarrhea
Abdominal pain
Lead to severe life threating dehydration
VARAEMIA –> PRESENCE OF VIRUS IN BLOOD
diagnosis and detection of rota virus ?
Electron microscopy EM :
Rotavirus particles can be detected from the stool through E microscope
Enzyme linked IMMUNOSORBENT ASSAY ( ELISA):
Involve detection of VP6 group A specific antigen in DIARRHEAL STOOL BY USING FLUOROSCEIN LABELED IMMUNOGLOBUIN
Passive particle agglutination test PPAT:
Based on antigen antibody interaction
PAGE : Polycrylamide gel electrophoresis :
Ritoviral double stranded RNA segments can be detected by electrophoresis on poly acrylamide gel
Reverse Transcription polymerase chain reaction RT PCR :
For detection of rotavirus in extraintestinal tissues BUT also for studying the correlation between disease severity and virus load and duration of viral shedding in stool
Treatment of rotavirus ?
healthy immune systems –> SELF LIMITED
Treatment is non specific –> primarily of ORAL REHYDRATION therapy to prevent dehydration
Zinc supplementation –> 2 pronged treatment of acute diarrhea
Probiotics –> Reduce duration of diarrhea caused of rotavrius
Prevention of rotavirus ?
Rotavirus transmitted by fecal-oral contact and possibly contaiminated surface
Good hygein like hand washing
Safe drinking water supplies
Sanitation
VACCATION :
Best way to protect child from rotavirus vaccine
Oral vaccines and are very effective
The vaccines differ in how they made the number of doses but are given ORALLY
both vaccines demonstrate similarly high lvls of protection against severe rotavirus gastroenteritis
