L23 Respiratory Viruses Flashcards
Most important Pediatric respiratory virus?
Respiratory Syncytial Virus (RSV)
The major respiratory pathogen in young children
Essentially all children infected in first 3 years of life
Disease most common and severe in first 6 months of life
Leading cause of mortality due to infectious disease
acute respiratory infection (ARI)
Transmission/Virology/Infectiveness/Pathology/Treatment of RSV?
Transmitted by large particle Aerosol/Fomites
ssRNA
Infectious from the onset of symptoms
Causative of Brochiolitis
Treatment:
Ribavarin is licensed (Not recommended to be given routinely)
Palivizumab: humanized monoclonal antibody that can reduce disease severity
Given to children with predisposed immuno condition (5 doses)
NO therapeutic effect!!! -nothing gained giving to someone already infected with it
Reduces hospitalization when given prophylactically
Can lead to resistant RSV
_______________________:
ssRNA
Second only to RSV as a cause of bronchiolitis in early childhood
virtually all children infected in first 5 years of life
Why is it often overlooked?
Human Metapneumovirus (HMPV)
ssRNA
Second only to RSV as a cause of bronchiolitis in early childhood
virtually all children infected in first 5 years of life
overlooked because it:
grows slowly in vitro
has a delayed cytopathic effect
usually requires added trypsin for activation of the fusion protein
Transmission/Infectiveness/Pathology/Treatment of Human Metapneumovirus (HMPV)
Transmitted by respiratory secretions (Direct contact/Large droplets)
Infectious from the onset of symptoms
Causes: LRTI, URTI, Otitis Media, Wheezing
NO vaccine/Antiviral
_______________________: Name originally coined because some of the disease signs are influenza-like and because, like influenza, the particle is medium-sized, has a lipid envelope, and has haemagglutinin and neuraminidase activities/
Which serotypes have the highest pathogenicity?
Treatment?
Human Parainfluenza Virus (HPIV): Name originally coined because some of the disease signs are influenza-like and because, like influenza, the particle is medium-sized, has a lipid envelope, and has haemagglutinin and neuraminidase activities
ssRNA
Pathogenicity of 1 and 3 >2>4
Treat w/ Steroids (croup) or DAS181 Sialidase fusion protein
_____________________:
DNA Virus
During attempts to establish tissue culture lines from tonsils and adenoids (hence the name) surgically removed from children, it was recognized that a transmissible agent was causing degeneration of the epithelial-like cells
Pathogenicity?
Treatment/Prevention?
Human Adenovirus (HAdV)
DNA Virus
During attempts to establish tissue culture lines from tonsils and adenoids (hence the name) surgically removed from children, it was recognized that a transmissible agent was causing degeneration of the epithelial-like cells
Can cause sever illness in immunocompromised individuals
Pneumonia
Hepatitis
Colitis
Pancreatitis
Meningoencephalitis
Common in Military boot camps => diverse people undergoing physical strain
ORAL VACCINE Available (Types 4/7) for military recruits
CIDOFOVOIR Antiviral
____________________: Responsible for 25% of common cold infections (second only to Human Rhinovirus (HRV))
Antibodies?
Reinfection?
Transmission?
Vector?
Human Coronavirus (HCoV): Coronaviruses are responsible for 25% of common cold infections
Endemic in the human population
Antibodies appear early in life and are ubiquitous by adulthood
– All age groups uniformly infected
– Winter-Spring seasonality in temperate regions
Reinfection does occur, and often within months of previous
– Suggests even homologous immunity may be short-lived
– Antibodies also appear not to be cross-protective
Person to person transmission in the hospital
Bats an ideal vector
Similar receptors to humans
Echolocagtion
Roosting
Why Quarantine was effective for SARS COV-1?
Why Quarantine was effective for SARS COV-1?
Viral load increased over time
Only infectious when symptomatic
_________________________:
RNA Picornavirus
ssRNA
Historically classified into two species (A & B) on the basis of capsid sequences
In 2006 HRV-C identified by a number of groups around the world
– Do not grow in standard cell lines
– Remained undiscovered despite widespread circulation in humans for at least 250 years
Treatment?
Human Rhinovirus (HRV)
RNA Picornavirus
Historically classified into two species (A & B) on the basis of capsid sequences
In 2006 HRV-C identified by a number of groups around the world
– Do not grow in standard cell lines
– Remained undiscovered despite widespread circulation in humans for at least 250 years
NO ANTIVIRAL
NO VACCINE
________________
RNA Picornavirus
Primarily affect GI tract
Associated diseases? (3)
________ is Key: Need a baseline to know when an increase from normal
Enteroviruses
RNA Picornavirus
Primarily affect GI tract
Polio most well known and severe , only one vaccinated against
Coxsackie Viruses cause CAN disease in Humans
Hand-Foot-Mouth
Surveillance is Key: Need a baseline to know when an increase from normal
