11-RESPI VIRUSES Flashcards
Interferons are cytokines released by our immune system in response to what type of microorganisms?
invading microorganisms especially RNA viruses
Interferons are more associated with which type of viruses
RNA or DNA?
Interferons are not antiviral agents but they induce what?
an antiviral state
What do interferons induce the production of
that inhibit the replication of viruses?
What are the two types of vaccines?
Killed microorganism and Attenuated
What characterizes killed microorganism vaccines?
part of the virus with short-lived immunity
What characterizes attenuated vaccines?
weakened version of the virus with long-lived immunity
What are the problems associated with attenuated vaccines?
storage issues and risk of causing actual disease in immunocompromised patients
RSV is a highly contagious virus affecting which system?
respiratory system
RSV is the leading cause of what in infants and young children?
lower respiratory tract infections
RSV infections contribute significantly to what public health concerns?
hospitalizations and medical costs worldwide
Who are the high-risk groups for severe RSV infections?
infants young children older adults immunocompromised individuals and those with chronic medical conditions
In immunocompetent individuals
how does RSV usually manifest?
During which season does RSV peak?
winter or cold season
Are respiratory viruses more common during cold weather?
majority peak during cold weather but some cause infections year-round
What family does RSV belong to?
Paramyxoviridae
What genus does RSV belong to?
Orthopneumovirus
What type of genome does RSV have?
negative-sense single-stranded RNA
Into how many major groups is RSV categorized based on genetic and antigenic differences?
two major groups
What are the two major groups of RSV?
RSV-A and RSV-B
Where does RSV replication occur in the host cell?
cytoplasm of the host cell
What is the first step in the RSV replication cycle?
attachment of the virion to the apical surface of polarized+ciliated airway epithelial cells via the G glycoprotein
Which RSV glycoprotein mediates attachment to host cell receptors?
G glycoprotein
Which RSV glycoprotein is responsible for membrane fusion and viral entry?
F glycoprotein
After entry
where is the RSV genome released?
What enzyme transcribes RSV RNA into mRNAs?
RNA-dependent RNA polymerase
What happens to RSV mRNAs after transcription?
they are translated into viral proteins
What are the next steps after translation of viral proteins in RSV replication?
viral RNA undergoes replication+copies of RNA and viral proteins are assembled to form progeny particles
Where does assembly of new RSV virions occur?
at or near the plasma membrane
How are new RSV virions released from the infected cell?
through budding from the plasma membrane
What is the structure of RSV?
enveloped virus with a helical nucleocapsid
How many viral proteins does the RSV genome encode?
11 viral proteins
Which two glycoproteins are crucial for RSV entry and pathogenesis?
fusion (F) and attachment (G) glycoproteins
What is the shape of RSV particles under electron microscopy?
pleomorphic+appearing as spherical or filamentous particles
What is the target cell of RSV infection?
cells of the respiratory epithelium
Through which route does RSV enter the body?
respiratory tract
Does RSV remain confined to the respiratory tract?
yes
Name viruses that enter through the respiratory tract but can cause systemic infections
measles+chicken pox (varicella)+rubella
What host response contributes to RSV disease severity?
excessive inflammation
Which severe diseases can RSV cause in vulnerable populations?
bronchiolitis+pneumonia+respiratory failure
Who are particularly at risk for severe RSV infection?
infants+young children+older adults
What is the main mode of RSV transmission?
droplet transmission via respiratory droplets from coughing or sneezing
How can RSV spread via contact transmission?
direct or indirect contact with contaminated surfaces or objects+then touching mouth+nose+or eyes
How can RSV be transmitted through aerosols?
via smaller respiratory particles or aerosols that remain suspended in air for an extended period
What are contaminated fomites in RSV transmission?
surfaces or objects like toys+doorknobs+shared items that can carry the virus
How does close personal contact facilitate RSV transmission?
through exchange of respiratory secretions by kissing or sharing utensils
Which infants are at highest risk for severe RSV infection?
premature infants born before 29 weeks of gestation
Which children are at high risk for RSV complications?
children under 2 years old with chronic lung disease or congenital heart disease
Which adults are at increased risk for severe RSV?
adults aged 65 years and older with weakened immune systems
Which chronic conditions increase RSV risk?
asthma+COPD+diabetes
What are common clinical manifestations of RSV in infants?
cough+wheezing+difficulty breathing+fever+poor feeding
How do RSV infections often present in adults and older children?
mild cold symptoms but can progress to more severe respiratory illness especially in individuals with underlying health conditions
What is typically involved in diagnosing respiratory syncytial virus (RSV)?
analyzing patient symptoms and conducting laboratory tests on respiratory samples
What are common laboratory methods for RSV diagnosis?
rapid antigen testing+molecular testing like RT-PCR+virus culture
What imaging may be used to evaluate severe RSV cases?
chest X-rays
What is the management for mild RSV cases?
oral hydration+pain relievers+rest+monitoring for worsening symptoms
What supportive care is given in severe RSV cases?
supplemental oxygen+intravenous fluids+respiratory support (mechanical ventilation if needed)
What antiviral medication may be considered for severe RSV cases?
ribavirin (effectiveness is limited)
What monoclonal antibody may be given to high-risk infants to prevent severe RSV disease?
palivizumab
What preventive measures can help prevent the spread of RSV?
frequent handwashing+avoiding close contact with infected individuals+keeping surfaces clean
Why is accurate and timely diagnosis of rhinovirus infections important?
for appropriate treatment+infection control measures+monitoring of potential complications especially in high-risk populations
What are general treatment and management principles for respiratory viral infections?
adequate fluid intake+rest+symptom relief medications+antibiotics for secondary bacterial infections
What are key prevention practices for respiratory viral infections?
frequent and thorough handwashing+cough etiquette+avoiding close contact with individuals exhibiting cold symptoms
What are some prevention strategies for RSV?
handwashing and hygiene+respiratory etiquette+avoiding close contact+potential maternal RSV vaccine+monoclonal antibody prophylaxis+development of pediatric RSV vaccine
What is a notable characteristic of rhinovirus infection timing?
causes year round infection but peaks during cold season
How is rhinovirus commonly transmitted?
through coughing+sneezing+touching contaminated surfaces
What is rhinovirus a leading cause of?
the common cold
Why is it challenging to develop effective vaccines or treatments for rhinovirus?
there are over 100 different strains of rhinovirus
Why can you get infected with rhinovirus multiple times?
antibodies produced are type specific and may not be protective against other strains
What makes rhinovirus a challenge in prevention and treatment?
it is highly contagious and has diverse strains
What family and genus does rhinovirus belong to?
Picornaviridae family+Enterovirus genus
What type of virus is rhinovirus?
non-enveloped positive-sense single-stranded RNA virus
What is rhinovirus’s primary role in disease?
primary causative agent of the common cold
How long is the rhinovirus genome?
approximately 7
What does the rhinovirus genome encode?
single polyprotein cleaved into structural and non-structural proteins
What is the shape of rhinovirus particles?
icosahedral with 30 nanometer diameter
What structural proteins make up rhinovirus?
VP1+VP2+VP3+VP4
How many serotypes of rhinovirus exist?
over 100 different serotypes
What receptors does rhinovirus bind to on human cells?
ICAM-1 (major group) or LDLR family (minor group)
Where does rhinovirus replication occur?
cytoplasm of host cells
What begins the rhinovirus replication cycle?
attachment to specific cell surface receptors
What happens after rhinovirus entry into host cells?
viral genome release and protein synthesis
How are new rhinovirus particles released?
assembled in host cytoplasm and released through cell lysis
How is rhinovirus primarily transmitted?
respiratory droplets and direct contact with contaminated surfaces
How long can rhinovirus survive on surfaces?
several hours
What are common clinical manifestations of rhinovirus?
runny nose+nasal congestion+sore throat+cough
What conditions can rhinovirus exacerbate?
asthma and chronic obstructive pulmonary disease (COPD)
When does rhinovirus prevalence peak?
fall and spring seasons
Where do rhinovirus transmission rates surge?
closed settings like schools and offices
What molecular feature complicates rhinovirus tracking?
multiple co-circulating strains per season
What environmental conditions favor rhinovirus stability?
colder temperatures and low humidity
Who contributes to rhinovirus community spread?
asymptomatic carriers
What does surveillance data track for rhinoviruses?
strain diversity and evolution
What triggers rhinovirus pathogenesis?
viral invasion of respiratory cells triggering immune responses
What are key symptoms of rhinovirus infection?
runny/stuffy nose+sore throat+cough+mild fever+headache/body aches
How is rhinovirus treated in immunocompetent individuals?
symptom management (antipyretics/pain relievers)
What type of immunity does rhinovirus infection confer?
serotype-specific (no cross-protection between strains)
When do antibodies typically develop in rhinovirus infections?
after recovery begins (not required for symptom resolution)
What is PCR used for in rhinovirus detection?
highly sensitive and specific molecular method to detect rhinovirus genetic material and distinguish between different strains
What advantage does PCR offer in rhinovirus diagnosis?
rapid identification of the virus and strain differentiation aiding in targeted treatment
What does viral culture involve for rhinovirus?
growing the virus in a laboratory from a patient’s respiratory sample
How does the sensitivity of viral culture compare to PCR for rhinovirus?
viral culture is less sensitive than PCR
What valuable information can viral culture provide for rhinovirus?
information about the viability and infectivity of the virus
What are examples of cell lines used in rhinovirus viral culture?
organ culture using ferret and human trachea epithelial cells+WI-38 and MRC-5 cell lines
What does serology (antibody testing) detect in rhinovirus diagnosis?
presence of antibodies against rhinovirus in the patient’s blood
What does a positive serology test indicate for rhinovirus?
past or recent infection
What is a limitation of serology in acute rhinovirus infections?
limited diagnostic value
What reagent is used in rhinovirus antibody testing?
antigen
How can clinical symptoms help in rhinovirus diagnosis?
characteristic symptoms like runny nose+sore throat+cough can suggest rhinovirus infection especially during peak seasons and absence of fever
Why is accurate and timely diagnosis of rhinovirus infections important?
crucial for appropriate treatment+infection control+monitoring complications especially in high-risk populations
What are the main principles of rhinovirus treatment and management?
adequate fluid intake+rest+symptom relief medications+antibiotics for secondary bacterial infections
What is the first step in rhinovirus prevention?
practice frequent and thorough handwashing with soap and water or alcohol-based hand sanitizer
What is recommended for cough etiquette to prevent rhinovirus?
cover coughs and sneezes with a tissue or inside of the elbow
What should be avoided to prevent rhinovirus transmission?
close contact with individuals exhibiting cold symptoms
What is a long-term prevention strategy for rhinovirus?
explore potential vaccine development targeting common rhinovirus strains
Which genus includes human coronaviruses HCoV-229E and HCoV-NL63?
Alphacoronavirus
Which genus includes porcine transmissible gastroenteritis virus (TGEV)?
Alphacoronavirus
Which genus includes SARS-CoV
MERS-CoV
Which genus includes human coronavirus OC43 and HKU1?
Betacoronavirus
Which genus primarily infects birds but also includes porcine respiratory coronavirus and mink coronavirus?
Gammacoronavirus
Which genus mainly infects birds and mammals
including porcine deltacoronavirus?
What is the causative agent of the 2003 outbreak in Guangdong
China?
What is the causative agent of the 2012 outbreak first reported in Saudi Arabia?
MERS-CoV
What is the causative agent of the 2019 outbreak leading to the COVID-19 pandemic?
SARS-CoV-2
Which coronavirus genus includes the virus responsible for COVID-19?
Betacoronavirus
What is the family name of all coronaviruses?
Coronaviridae
Which structural feature is characteristic of coronaviruses?
enveloped viruses with crown-like spike proteins
Which protein on SARS-CoV-2 binds to ACE2 receptors?
spike protein
What is the primary mode of transmission for SARS-CoV-2?
respiratory droplets
Which coronavirus genus includes viruses that can infect both birds and mammals?
Deltacoronavirus
Which coronavirus genus includes viruses that primarily infect birds?
Gammacoronavirus
Which age group is at higher risk for severe COVID-19 illness?
older adults
Which underlying factor increases risk for severe COVID-19?
underlying medical conditions
What is the clinical presentation of COVID-19 in some individuals?
asymptomatic infection
What are common mild symptoms of COVID-19?
fever+dry cough+fatigue+loss of taste or smell
What severe complications can SARS-CoV-2 cause?
pneumonia+acute respiratory distress syndrome (ARDS)+multi-organ failure
What is the timeline event for the 2020 global health declaration?
WHO declares COVID-19 a global pandemic
What is the first widely available COVID-19 vaccine in the Philippines?
Sinovac COVID-19 vaccine
Which variant drove a new wave of COVID-19 cases in 2022?
Omicron variant
What is the gold standard test for COVID-19 diagnosis?
RT-PCR
Which COVID-19 test detects viral RNA?
RT-PCR
What type of sample is typically collected for COVID-19 testing?
nasal swab
Which proteins do antigen tests detect in COVID-19?
viral antigens
What is the primary purpose of monoclonal antibody therapies in COVID-19?
treatment for high-risk patients
Which drug is an approved antiviral for COVID-19 treatment?
remdesivir
What medication is used to reduce inflammation in severe COVID-19 cases?
dexamethasone
What is the primary prevention strategy against COVID-19?
vaccination
Which influenza type has the broadest host range?
Influenza A
What causes major antigenic changes in influenza viruses?
antigenic shift
Which influenza type causes seasonal epidemics but not pandemics?
Influenza B
Which influenza type typically causes mild respiratory infections?
Influenza C
What is the recommended physical distance to prevent COVID-19 transmission?
6 feet
Which diagnostic method provides COVID-19 results fastest?
antigen test
What type of immunity does COVID-19 vaccination provide?
acquired immunity
Which influenza type is responsible for most pandemics?
Influenza A
What is the key epidemiological factor in COVID-19 diagnosis?
exposure history
Which therapy uses casirivimab/imdevimab for COVID-19?
monoclonal antibodies
What is the primary transmission route for SARS-CoV-2?
respiratory droplets
Which influenza mutation mechanism causes minor antigenic changes?
antigenic drift
What percentage range represents Influenza A’s severity and host range?
(Scale not specified - text mentions “broadest range and highest severity” without numerical values)
Which influenza virus caused the 1918 Spanish Flu pandemic?
H1N1
Which influenza virus caused the 1957 Asian Flu pandemic?
H2N2
Which influenza virus caused the 1968 Hong Kong Flu pandemic?
H3N2
Which influenza virus caused the 2009 Swine Flu pandemic?
H1N1
What are the two major surface glycoproteins of influenza viruses?
hemagglutinin+neuraminidase
What do the numbers in influenza virus names like H1N1 and H2N2 refer to?
hemagglutinin and neuraminidase subtypes
Which protein facilitates influenza virus entry into host cells?
hemagglutinin
Which protein aids in the release of new influenza virus particles from host cells?
neuraminidase
What type of genome does the influenza virus have?
segmented negative-sense RNA genome
What process allows influenza viruses to exchange genetic material and create new combinations?
genetic reassortment
What is the structural feature that enables influenza virus replication and reassortment?
segmented genome
What is the main clinical manifestation of influenza involving body temperature?
fever
What common respiratory symptom is caused by influenza?
cough
What symptom of influenza involves painful inflammation of the throat?
sore throat
What influenza symptom is characterized by widespread body pain?
muscle aches
What is a common symptom of influenza involving lack of energy?
fatigue
What severe complication can influenza cause in high-risk groups?
pneumonia
What is the main risk of severe influenza cases?
respiratory failure and death
Which age group is most vulnerable to severe influenza complications?
Individuals over 65 years old
Which pediatric group faces the highest influenza risk?
Children under 5 (especially <2 years old)
Why are pregnant women at higher risk for influenza complications?
Pregnancy alters immune function and cardiorespiratory systems
What chronic conditions increase influenza risk?
Asthma+diabetes+heart disease
What is the primary influenza prevention method for high-risk groups?
Annual vaccination
Which antiviral medication inhibits influenza viral replication?
Oseltamivir (Tamiflu)
What type of immunity does influenza vaccination provide?
Strain-specific protection against predicted seasonal variants
Which influenza protein facilitates host cell entry?
Hemagglutinin
Which influenza protein enables viral particle release?
Neuraminidase
What genetic feature enables influenza virus diversity?
Segmented genome allowing genetic reassortment
Which influenza type has the broadest host range?
Influenza A
Which influenza type primarily infects humans?
Influenza B
Which influenza type causes mild respiratory illness in humans and animals?
Influenza C
What is the key difference between antigenic drift and shift?
Drift: minor mutations; Shift: major reassortment
Which coronavirus binds ACE2 receptors for host entry?
SARS-CoV-2
Which betacoronavirus originated in the Middle East from camels?
MERS-CoV
Which cell lines are used for rhinovirus culture?
WI-38 and MRC-5
What receptors do major-group rhinoviruses bind?
ICAM-1
What receptors do minor-group rhinoviruses bind?
LDLR family
Is rhinovirus immunity cross-protective across serotypes?
No (serotype-specific immunity)
