RNA Virus Flashcards
- Sand shape appearance in electron microscope
- Acquired through inhalation from infected rodent or direct contact
Arenavirus
Tacaribe, Guanarito, Junin and Machupo
New World Arena Virus
o Mus musculus
o Mastomys natalensis
o Lymphocytic Choriomeningitis
o Lassa virus
Old World Arena Virus
ARENAVIRUS
rare case of aseptic meningitis
Lymphocytic Choriomeningitis
ARENAVIRUS
hemorrhagic fever + influenza like
Lassa virus
- Star appearance in EM
- Account to 2-9% of pediatric gastroenteritis in the world
Astrovirus
Type and Organ damage associated with Bunyavirus
— Rift valley fever virus
Phlebovrift – (Brain and liver))
Type and Organ damage associated with Bunyavirus
— LaCrosse and California encephalitis
Orthobunyab – (Brain)
Type and Organ damage associated with Bunyavirus
— Crimean Congo Hemorrhagic fever
Nairovirus (Vascular, Endothelium and Liver)
Type and Organ damage associated with Bunyavirus
— rodent borne bunyavirus
— Disease is known as hemorrhagic fever with renal syndrome (HFRS)
Hantavirus
Small (30-38nm) rounded nonenveloped that causes gastroenteritis to human
Calicivirus
two types of calicivirus
Norovirus / Norwalk virus
Sapovirus
CALICIVIRUS
o Associated with 80% of nonbacterial acute gastroenteritis in underdeveloped countries
o Due to ingestion of contaminated shell fish and water
Norovirus/Norwalk virus
CALICIVIRUS
o Cup-shape in EM, also associated with gastroenteritis
Sapovirus
• Pleomorphic, roughly spherical
• Extremely fragile and difficult to culture
• Resemble halo/crown on external surface of the virus
Coronavirus
CORONAVIRUS
– acquired from civet cat that originated from Guangdong, China
SARS-COV1
CORONAVIRUS
– acquired from camel that originated in Middle East
MERS-COV
CORONAVIRUS
– possibly acquired from Pangolin (bat) that originated from Wuhan, China
SARS-COV2
SARS-COV2 detection
Direct – microscopy/viral nucleic acid (RT-PCR)
Indirect – serological testing (Antigen)
SARS-COV2 Variant of concern
Alpha (B117) –
Beta (B1351) –
Gamma (P1) –
Delta (B16172) –
United Kingdom
South Africa
Brazil
India
• Most pathogenic hemorrhagic virus
threadlike due to long filamentous morphology in EM
Filovirus
Filovirus Types
A. Marburg hemorrhagic fever
B. Ebola Virus
FILOVIRUS
• 25% fatality rate
• Acquired from African Green Monkey
Marburg hemorrhagic fever
FILOVIRUS
• Emerging virus due to eating of wild animal meat in Africa
• Acquired through direct contact with infected animal or human
• 80% fatality rate
Ebola Virus
Derived from flavus which means yellow
Flavivirus
Flavivirus types
A. Yellow Fever
B. Dengue Virus
C. St. Louis Encephalitis
D. Zika Virus
E. West Nile Virus
F. Hepatitis C
FLAVIVIRUS
Yellow fever three cycles:
- Sylvatic (monkey; transmitted by mosquitoes Aedes aegypti)
- Urban (human)
- Intermediate (human)
FLAVIVIRUS
• Dengue vectors - _________
• It has 4 serotypes (1 to 4)
• Major protein in dengue virus called “__” for enveloped protein
Denge Virus
— Aedes,aegypti, Aedes albopictus, and Aedes polynesiensis
— E
FLAVIVIRUS
Transmitted by Culex mosquitoes and mostly in summer months
St. Louis Encephalitis (SCE)
FLAVIVIRUS
Spread by daytime Aedes aegypti and albopictus
cause of Guillain-Barre syndrome in adults
Zika Virus
FLAVIVIRUS
• Vector is Culex mosquito
• Maintained in bird-mosquito cycle such as crows, ravens
West Nile Virus
FLAVIVIRUS
• Associated with chronic liver disease
• Not an arthropod because the MOT is parenteral etc.
Hepatitis C
Previously under calicivirus
High case fatality rate in pregnant women (10-20%)
Hepevirus
Pleomorphic single strand with 8 segments
Transmitted through respiratory secretions
Orthomyxovirus
With three serotypes
o A – naturally infects ____
o B and C – ___
Influenza is further subdivided based on Hemagglutinin (HA) and neuraminidase (NA)
o Hemagglutinin are _ shape spikes
o Neuraminidase are ____ spikes
Orthomyxovirus
A - animals
B&C - human
rod;
mushroom
refers to alteration to influenza HA and NA antigens
Antigenic drift
occurs after having a completely new novel type
Antigenic shift
ONLY ___________ found in human population
o _____ – Spanish Flu
o _____ – Asian Flu
o _____ – Hongkong Flu
o ____ – Avian Flu
H1 H2 H3 N1 N2
o H1N1
o H2N2
o H3N2
o H5N1
Do not have segments that’s why they don’t undergo antigenic shift
paramyxovirus
paramyxovirus types
A. Mumps or Rubulavirus
B. Parainfluenza virus
C. Respiratory Synctial Virus (RSV) or Pneumovirus
D. Measles or Morbilivirus
E. Metapneumovirus
F. Nipah virus
PARAMYXOVIRUS
Characterized by inflamed salivary gland (infection of parotid gland) accompanied by high temperature and fatigue
Mumps or Rubulavirus
PARAMYXOVIRUS
Second cause of pneumonia and bronchiolitis in children after RSV
• 4 serotypes
o Parainfluenza 1 is associated with ___ (larygeotracheobronchitis)
o ____ is severe and fatal associated with -
Parainfluenza virus
croup
Parainfluenza 3
PARAMYXOVIRUS
• Most significant cause of acute RTI in children under 5 years of age worldwide
• Contains a surface F protein (Fusion)
• Leads to giant multinucleated cells
Respiratory Synctial Virus (RSV) or Pneumovirus
PARAMYXOVIRUS
Highly contagious accompanied by maculopapular rash and fever
Measles or Morbilivirus
PARAMYXOVIRUS
Associated with winter epidemics bronchiolitis and pneumonia which is common in children
Metapneumovirus
PARAMYXOVIRUS
Can cause febrile encephalitis in human
Nipah Virus
• Simplest of RNA viruses with highly structured capsid but limited surface elaboration
• Consist of 30% RNA and 70% protein
Picornavirus
PICORNAVIRUS
The most common cause of aseptic meningitis or inflammation of brain parenchyma
• Primary MOT: Respiratory or gastrointestinal
Enterovirus
PICORNAVIRUS
Major cause of cold virus
Resistant to detergents, lipid solvents, and temperature extremes, but sensitive to pH less than 6
Rhinovirus
Respiratory Enteric Orphan
Reovirus
REOVIRUS
The most common cause of viral gastroenteritis in infants and children worldwide
rotavirus
REOVIRUS
With 12 RNA segments
• Associated with Colorado tick fever
Coltivirus
Reovirus examples
A. Rotavirus
B. Coltivirus
Picornavirus examples
A. Enterovirus
B. Rhinovirus
Retrovirus examples:
A. Oncovirus
B. Lentivirus
_____ are oncovirus but not cytolytic
o HTLV 1 is known as ____
o HTLV 2 is known as _____
HTLV-1, HTLV-2 and HTLV-5
T cell leukemia
Hairy Cell Leukemia
HIV antigens :
HIV screening test:
HIV confirmatory test:
p24, gp41, gp120, gp160
S: ELISA
C: Western blot
Worldwide prevalence; main groups are M, N, O whereas A-K are subgroups
HIV 1
HIV in West Africa
HIV 2
o Bullet shape appearance
o It is characterized by saliva frothing with painful spasm
o May lead to coma or death
o Associated with negri bodies in brain tissues of infected animals
and humans
Lyssavirus / Rabies
(under RHABDOVIRUS)
Togavirus examples
- Alphavirus
- Rubella or Rubivirus
- Chikungunya virus
TOGAVIRUS
associated with equine encephalitis and transmitted by mosquitos
Alphavirus
TOGAVIRUS
German measles or 3-day measles – may lead to congenital defect if pregnant women is infected
Rubella or Rubivirus
TOGAVIRUS
associated with myositis and arthritis which is transmitted by Aedes aegypti
Chikungunya virus
