Coxsackievirus

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Transcript Coxsackievirus

Coxsackievirus
Shandong university school of medicine
Class 2 Grade 2002 clinical medicine for seven years
 Kayla Nicole
Clingerman of
Woollum, KY
was tragically
taken from us
at the age of 6
from Viral
Meningitis.
October 13,
1997 - October
11, 2004
 This is a
picture of
Seven month
old Olivia
Grace Hamilton
at Cayuga
Lake in 2004.
Viral Meningitis.
tragically took
her life.
Introduction
 Late summer or early fall…It’s not yet cold
or flu season, but your child is sick.
Consider coxsackievirus.
 It’s often the culprit when parents leave a
doctor’s appointment without knowing what
disease their child has.
History
 1947 Coxsackievirus was first identified
 1957 associated with "hand, foot and
mouth" disease and first documented
 1988 epidemics occurred
 1994 the largest epidemic in Britain
Most of the 952 cases were children
aged one to four
Definition
 Coxsackieviruses, a family of enteroviruses.
These viruses share in common that they
infect the human intestines (and stool), but
they can cause symptoms throughout the
body.
 spherical,2030nm.
 Icosahedral
symmetry,
 non-enveloped.
 Capsid:VP1-VP4
 +ssRNA.
 Capsid:VP1-VP4
VP1 is associated with absorption of
VP4 locates in the capsid
virus
Once VP1 bound to receptor on the
target cell,then VP4 is released,+ssRNA
enter the cell.
 +ssRNA:infectious.
Pathogenic mechanism
 To cell
 CV are characterized by their ability to cause CPE in tissue
culture and by their capacity to initiate acute disease by
inducing apoptosis within targeted organs in vivo. So,these
viruses are considered highly cytolytic.
 CV can establish persistence in susceptible cells,
indicating that a regulatory mechanism may exist to shut off
viral protein synthesis and replication under certain
situations. The persistence of coxsackieviral RNA is of
particular medical interest due to its association with
chronic human diseases.
To defence system
 Basically, the virus confuses the body's defence system.
 First, the body detects the presence of an enemy using its
antigen recognition system. The virus, meanwhile, may
mimic the protein structure of the heart muscle, and
sometimes, may even interact and alter the antigenic
configuration there.
 Second, the body's defence system reads the signals
wrongly. It deploys killer white cells to attack the enemy.
The white cells do two things. One, it fires virus-seeking
missiles called antibodies to neutralise Coxsackie B and
removes it. Two, the white cells also attack the wrong
target: the heart. the white cells attack one of its own life
support systems.
Immunity
 sIgA is very important to resist absorption
and replication of virus in alimentery tract.
 Neutralizing Ab in serum can prevent the
diffusion of virus,which can last for several
years,even all the life.
 Inapparant infectors also get firm immunity.
Incubation
 The incubation period (the time
between infection and the onset of
symptoms) for most coxsackie
virus infections is about 2 to 10
days
symptoms
 Hand-foot-and-mouth disease
mainly affecting young children
 Rash.
 Nonspecific fever, headache
 Herpangina.
 Respiratory Infection.
 Gastrointestinal Infection.
Hand-foot-and-mouth disease
 rash
 conjunctivitis
 Herpangina
 Meningitis
 Viral myocarditis
Duration
 The duration usually varies, depending on
the specific type.
 Coxsackie fever often asymptoms, a child's
temperature may return to normal within 24
hours, although the average fever lasts 3 to
4 days. In pleurodynia, fever and muscle
pain usually last 1 to 2 days, and in
herpangina, symptoms generally last 3 to 6
days.
Diagnose
 Diagnosis is made based on the
history and physical exam
 Lab tests are available
test stool or fluids from the back of the throat
 Serum test for specific Ab
 PCR for viral nucleic acid
Susceptible group
 Most common in young people.
 Adults can be infected, but this is much
less common
 Most infections occur in the summer or
early fall, with a peak from August to
October in the northern hemisphere.
Transmission
 Coxsackieviruses are present both in
the stool and in the respiratory
secretions
Fecal-oral transmission
Droplet transmission
Contact transmission
Prevention
 There is no vaccine to prevent
coxsackie virus infection
 Hand washing is the best
prevention,especially after
toileting and before eating—can
help reduce their spread
Treatment
 Antibiotics do not help with coxsackievirus
infections
 Plenty of fluids is useful
 Acetaminophen (such as Tylenol) may be
given to relieve any minor aches and pains
 Most children with a simple coxsackie
infection recover completely after a few
days at home.
 Last year, a drug called acyclovir, an antiviral chemical normally used to treat
herpes simplex,made a surprising success
in treating patients with Coxsackie A16.
The study was not conclusive.
 It speculated that in these patients,
something else was at work: these are the
interferons, which are chemical
messages sent from cell to cell like
warnings to uninfected cells to defend
themselves. .