Positive sense RNA Flashcards by Khienja Gonzaga

Is labile and transient

RNA VIRUS

How well did you know this?

Not at all

Perfectly

Most RNA virus replicate in the

Cytoplasm

How well did you know this?

Not at all

Perfectly

Cells cannot replicate RNA.

RNA viruses must encode an RNA-dependent RNA polymerase

How well did you know this?

Not at all

Perfectly

determines the mechanisms of transcription and replication

Genome structure

How well did you know this?

Not at all

Perfectly

Prone to mutations

RNA VIRUS

How well did you know this?

Not at all

Perfectly

determine how viral messenger RNA (mRNA) is generated and proteins are processes

genome structure polarity

How well did you know this?

Not at all

Perfectly

RNA viruses, except for (+) RNA genome, must carry?

polymerases

How well did you know this?

Not at all

Perfectly

All negative RNA viruses are

Enveloped

How well did you know this?

Not at all

Perfectly

(+) RNA genome resembles mRNA and is
translated into a polyprotein which is
proteolyzed. A (-) RNA template is used for
replication, early proteins are
translated from the genome and late
proteins from smaller mRNAs transcribed
from template

Picornaviruses,
Togaviruses,
Flaviviruses,
Caliciviruses,
Coronaviruses

How well did you know this?

Not at all

Perfectly

(-) RNA genome is a template for individual
mRNAs, but full-length (+) RNA template is
required for replication. Orthomyxoviruses
replicate and transcribe in the nucleus, and
each segment of the genome encodes one
mRNA and is a template

Orthomyxoviruses,
Paramyxoviruses,
Rhabdoviruses,
Filoviruses,
Bunyaviruses

How well did you know this?

Not at all

Perfectly

(+/-) Segmented RNA genome is a
template for mRNA (+RNA). (+) RNA may
also be encapsidated to generate the (+/-_
RNA and then more mRNA

Reoviruses

How well did you know this?

Not at all

Perfectly

(+) Retrovirus RNA genome is converted
into DNA, which is integrated into the host
chromatin and transcribed as a cellular gene

Retroviruses

How well did you know this?

Not at all

Perfectly

Positive sense RNA

● Picornaviridae
● Togaviridae
● Flaviviridae
● Caliciviridae
● Coronaviridae

How well did you know this?

Not at all

Perfectly

● Small (~30nm; from the Italian word piccolo, meaning “small”)
● Nonenveloped
● Single-stranded positive-sense RNA viruses
● Among the simplest of the RNA viruses

Picornaviridae

How well did you know this?

Not at all

Perfectly

Highly structured capsid that has limited surface elaboration. This family includes:

Enterovirus
Cardiovirus
Parechovirus
Rhinovirus
HAV

How well did you know this?

Not at all

Perfectly

✅Morphology :Naked + ssRNA (icosahedral symmetry)
✅Transmission Oral-fecal route
✅Pathogenesis : Replicates in motor neurons in anterior horn of spinal cord causing paralysis

Spectrum of disease Poliomyelitis and Meningitis
- Abortive poliomyelitis; non-paralytic poliomyelitis and paralytic poliomyelitis

Poliovirus

How well did you know this?

Not at all

Perfectly

Diagnosis for poliovirus

Cowdry B intranuclear inclusions

How well did you know this?

Not at all

Perfectly

Polio vacvine that is composed of killed virus

Salk

How well did you know this?

Not at all

Perfectly

OPV vaccine live attenuated virus

Sabin

How well did you know this?

Not at all

Perfectly

Polio virus is inactivated when heated at

55°C for 30 minutes, but Mg2+
prevents this inactivation.

How well did you know this?

Not at all

Perfectly

purified poliovirus is inactivated by a_____ much higher concentrations of____ are required to disinfect sewage containing virus in fecal suspensions and in the presence of other organic matter.

chlorine concentration of
0.1 ppm,

How well did you know this?

Not at all

Perfectly

Most strains can be grown in primary or
continuous cell line cultures derived from
a variety of human tissues or from monkey kidney, testis, or muscle but not
from tissues of lower animals.

Poliovirus

How well did you know this?

Not at all

Perfectly

Mouth is the portal of entry for poliovirus and primary multiplication takes place in the?

Oropharynx or intestine

How well did you know this?

Not at all

Perfectly

Poliovirus Antibodies appear early in
the disease, usually_____ paralysis
occurs

Before

How well did you know this?

Not at all

Perfectly

Incubation period of poliovirus

7-14 days or 3-35 days

Hands foot and mouth disease in humans

Coxsackie A virus

(Herpangina, acute Pleurodynia (B) hemorrhagic conjunctivitis, HFMD meningitis)

Coxsackie A

1/3 myocarditis

Coxsackie B

Pleurodynia, severe generalized disease of infants, pericarditis and myocarditis and aseptic meningitis

Coxsackie B

Is caused by all types of group B and by group A most commonly A7 and A9

Coxsackie virus Aseptic meningitis

Fever, malaise, headache, nausea and abdominal pain are common early symptoms

Poliovirus

Disease progress to mild muscle weakness suggestive of is caused by

Paralytic poliomyelitis

is a severe febrile pharyngitis that is caused by certain

Herpangina by coxsackie A

also known as epidemic myalgia caused by group B viruses. Fever and stabbing chest pain are usually abrupt in onset but are sometimes preceded by malaise, headache, and anorexia.

Coxsckie B pleurodynia

Aseptic meningitis,URTI, febrile illness with or without rash, infantile diarrhea and hemorrhagic conjunctivitis

ECHO (Enteric Cytopathic Human Orphan) virus

Transmission for rhinovirus

Aerosol droplets and hand to nose contact

Rhinovirus replicates better at what temperature

33c

Number 1 cause of common colds

Rhinovirus

Hepatitis A serotype

Enterovirus 72

replicated in the GI tract and then spreads to the liver during a brief viremic period

Hepatitis virus

self-limited, short incubation hepatitis and anicteric hepatitis

Hepatitis A

Hepatitis A diagnosis

Anti- HAV IgM

Hepatitis A treatment and prevention

administration of immune globulin during IP and vaccination (killed virus)

Togaviridae

Rubella virus

Rubella virus MOT

Respiratory droplets and transplacental

Rubella prevention and control

MMR vax

Other names for RUBELLA

German measles 3day measles

IP for rubella

14-21 days

Period of communicability

1 week before and after appearance of rash

Most characteristic clinical feature of rubella

Postauricularlymphadenipathy

Enanthem of Rubella

Forchheimer spots

True or false Measles natural infection leads to lifelong immunity

True

In congenital rubella greatest early fetal development when cell differentiation is at the peak at?

First trimester

Chromosomal breakage and inhibition of mitosis

Rubivirus

Body parts affected by rubella virus

Heart, eye, CNS

In rubella virus Dermal extramedullary hematopoiesis results to

Blue muffin appearance

Flaviviridae viruses

Dengue virus Hepatitis C Zika virus Yellow fever West nile virus

bite of female Aedes aegypti mosquito ( A. albopictus)

Dengue

Diagnosis of dengue

NS1 antigen, RT-PCR, Dengue Diagnosis, IgM and IgG and CBC, platelet count

Influenza like syndrome characterized by biphasic fever, myalgia, arthralgia, rash, leukopenia and lymphadenopathy

Dengue (break bone fever)

Severe often fetal, febrile disease characterized by capillary permeability, abnormalities of hemostasis and protein losing shock syndrome

Dengue hemorrhagic fever

Is due to the production of large amount cross reacting antibody at the time of a second dengue infection antibody dependent enhancement

Hemorrhagic shock syndrome

Head ache Body malaise Myalgia Arthralgia Retro orbital pain Anorexia Nausea Vomiting Diahhrea Flushed skin Rash Herman sign

Dengue without warning sign

With fever lasting to 2-7 days • Abdominal pain or tenderness • Persistent vomiting • Clinical signs of fluid accumulation • Mucosal bleeding • Lethargy, restlessness • Liver enlargement • Laboratory: increase in Hct and/or decreasing platelet count

Dengue with warning signs

Lives in or travels to a dengue-endemic with fever of and any of the above clinical manifestations for dengue with or without warning signs, plus any of the following: • Severe plasma leakage, leading to: - Shock - Fluid accumulation with respiratory distress • Severe bleeding • Severe organ impairment - Liver: AST or ALT >1000 - CNS: e.g., seizures, impaired consciousness - Heart: e.g., myocarditis - Kidneys e.g., renal failure

Severe dengue

enveloped, icosahedral, non-segmented, (+ssRNA) [ at least 6 serotypes]

Hepatitis C under flaviviridae

Hepatitis C transmission

(major) blood-borne IV drug users; (minor) NSI, during birth and sexual

Replication of HCV in the liver is enhanced by a liver-specific microRNA called—- This micro-RNA acts by increasing the synthesis of HCV mRNA. The death of the hepatocytes is probably caused by immune attack by cytotoxic cells

miR-122.

Hepatitis C diagnosis

anti-HCV antibodies, recombinant immunoblot assay (RIBA) and PCR (HCV-RNA)

Hepatitis C prevention Acute hepatitis C:

Peginterferon alfa

Chronic hepatitis C prevention

Peginterferon alta-za and ribavirin if genotype 1, add: protease inhibitor (boceprevir, simeprevir)

In hepatitis C death of hepatocytes is caused by

Immune attack by cytotoxic T cells

Hepatitis C incubation

8 weeks

Hepatitis C resembles

Hepatitis B

HCV infection also leads to significant autoimmune reactions and extrahepatic manifestations, including:

• Thyroiditis • Autoimmune hemolytic anemia • ITP • MPGN • DM • leukocytoclastic vasculitis • increase risk of B-cell NHL • lichen planus orphyria cutanea tarda

is the main cause of essential mixed cryoalobulinemia

HCV

Zika virus transmission

Aedes mosquito bites sexual vertical transmission possible

conjunctivitis, low-grade fever, muscle and joint pain, headache, and photophobia. Complications: microcephaly and Guillain-Barre syndrome

Zika virus

Zika virus treatment

Supportive care

Yellow fever transmission

Monkey or human

characterized by jaundice and fever Prostration and shock occur, accompanied by upper gastrointestinal tract hemorrhage with hematemesis ("black vomit")

Yellow virus

Yellow virus treatment

Mosquitos control and live attenuated vaccine

West nile virus transmission

Bite of culex mosquito

West nile virus causes encephalitis

True

Calciviridae

Norwalk virus

Norovirus or norwalk virus transmission

Oral fecal

Most common viral gastroenteritis in adult

Norovirus or norwalk

enveloped helical non-segmented, (+ SSRNA), w/ prominent club-shaped spikes form a "corona"

Coronavirus

Reservoir of coronavirus

horseshoe bat; Immediate host: civet cat

Spectrum disease of coronavirus

1. Common colds (2nd to rhinovirus) 2. SARS 3. MERS-COV 4. COVID-19

Positive sense RNA Flashcards

(90 cards)