Viruses Flashcards
“PICORNAVIRUS overview
(the peak-orna animal nursery)”
Features: “* +ssRNA
- direct transl by host RNA Pol
- replicates in cytoplasm
*Naked
* Polyprotein product (cleaved w viral protease)”
Reservoir/Transmission: *Fecal oral route (except rhinovirus)
Diseases: “A: Hep A
B: Enterovirus (Birds) = Coxsackie A/B, Poliovirus, Echovirus
C: Rhinoviruses (Common Cold)
PERCH”
Diagnosis:
Treatment:
Vaccines:
RNA Viruses (+) sense
Enterovirus
Features: Poliovirus, Coxsackie A & B, Echovirus (3 most common causes of aspetic meningitis)
Reservoir/Transmission: Birds
Diseases: * #1 cause of aspetic meningitis (normal glucose, high protein CSF); mostly affects kids
Diagnosis:
Treatment:
Vaccines:
RNA Viruses (+) sense
“Poliovirus
(flamingo breeding pool)”
Features: “Picornavirus Family (+ssRNA, Naked, Polyprotein product, Acid stable)
“
Reservoir/Transmission: * Fecal oral route
Diseases: “* Replicates in oropharynx (tonsils) & sm intestine (Peyer’s patches) –> bloodstream & CNS
Destroys anterior horn (LMN) of spinal cord
Symptoms: Malaise, HA, fever, nausea, weakness, hypotonia, flaccid paralysis, atrophy, faciculations, hyporeflexia, muscle atrophy”
Diagnosis: “CSF with pleocytosis (high WBC, slight increase in protein)
* Virus recovered from stool/throat”
Treatment:
Vaccines: “ Inactivated vaccine: (IgG response, no IgA); only form used in US
- Prevents vaccine-associated poliovirus
*Live attenuated oral:l (IgG & IgA response); provides herd immunity w person to person contact (used in developing countries)”
RNA Viruses (+) sense
“Coxsackievirus
(coxsackie cockatoos)”
Features: “Picornavirus Family (+ssRNA, Naked, Polyprotein product, Acid stable)
- Infection common during summer/fall
“
Reservoir/Transmission: * Fecal oral route
Diseases: “Coxsackie A:
*Hand, foot & mouth disease: fever, red vasicular rash 1-2 days post-fever; poor appetite, malaise, sore throat –> meningitis, encephalitis, flaccid paralysis (lymphadenopathy ABSENT)- Herpangina: painful sores in mouth (1-2 days post fever)
*Aspetic meningitis
- Herpangina: painful sores in mouth (1-2 days post fever)
- Acute hemorrhagic conjunctivitis
Coxsackie B:
*Devil’s Grip / Bornholm’s Disease / Pleruodynia: extreme sharp unilateral pain in lower chest with difficulty breathing
*Myocarditis –> Dilated cardiomyopathy (pericarditis w/ blue cells seen on biopsy of myocardium)
* Associated with hepatitis”
Diagnosis: *PCR
Treatment: * Supportive care
Vaccines:
RNA Viruses (+) sense
“Rhinovirus
(rhino petting zoo)”
Features: “Picornavirus Family* (+ssRNA, Naked, Polyprotein product)
- Acid labile*
- Grows best at 33’C/cold
- MANY serotypes (no vaccine/tx)”
Reservoir/Transmission: * Inhalation of resp droplets or fomites that attach to ICAM-1 to enter host cells
Diseases: “* Upper resp tract infection (URI) - # 1 cause of the common cold”Diagnosis:
Treatment:
Vaccines: No vaccine/tx due to MANY serotypes
RNA Viruses (+) sense
“Hep A (HAV)
(hungry hungry hep A hippos)”
Features: “Picornavirus Family (+ssRNA, Naked, Polyprotein product, Acid stable)
Councilman bodies (eosinophilic apoptotic globules) on liver biopsy (also Yellow Fever)
“
Reservoir/Transmission: “ Fecal oral route: enters mouth & replicates in liver
* Contaminated shellfish in developed countries (produce too)
*Contaminated water in developing countries
- Incubation period = 15-50 days (avg 28); virus excretion can occur for up to 3 wks after symptom onset
- Risk factor: underlying liver disease”
Diseases: “* Self-limiting illness that lasts ~1 mo
*No chronic state - General symptoms: fever, malaise, jaundice (except in children), anorexia, N/V, elevated LFTs
*Adults are more likely to be symptomatic than kids
Smokers develop aversion to smoking”
Diagnosis: * Virus in blood/feces after 10-12 days
Treatment:
Vaccines: “ Inactivated vaccine (used in endemic areas, chronic liver pts, sexually active MSMs); can be used for PPX pre-exposure > 2 wk before - Ig for ppx pre-exposure < 2 wk before”
RNA Viruses (+) sense
Hep E (HEV)
Features: “* Acid stable
* Naked”
Reservoir/Transmission:
Diseases: “Fever, jaundice, elevated ALT/AST (all Hepatitis viruses)
* Self limiting
* No carrier state”
Diagnosis:
Treatment:
Vaccines:
RNA Viruses (+) sense
“Norovirus
(cali sea cruise)”
Features:”* Calicivirus
+ssRNA
* Naked
Polyprotein product”
Reservoir/Transmission: “ Raw shellfish (fecal oral route)
* Cruises & daycare (contact, fomites)”
Diseases: “Presents 12-48 hr after exposure & resolves in 1-4 days (shed in stool 4 wk post-infection)
* Explosive, watery diarrhea, cramps, fever, chills
*Most common cause of viral gastroenteritis in all age groups worldwide”
Diagnosis: *PCR
Treatment:
Vaccines:
RNA Viruses (+) sense
“FLAVIVIRUS
(flavor packed flavi)”
Features: “* +ssRNA
* Enveloped
* non-segmented RNA”
Reservoir/Transmission:
Diseases: West Nile, Dengue Fever, Yellow Fever, Hep C
Diagnosis:
Treatment:
Vaccines:
RNA Viruses (+) sense
West Nile Virus
Features: “* +ssRNA
* Enveloped
* non-segmented RNA”
Reservoir/Transmission: “* birds (crows, blue jays; reservoir)
* Culex mosquitoes (vector)”
Diseases: “*West Nile fever (20%): HA, vomiting, confusion
* Neurologic disease (1%, especially if elderly)”
Diagnosis: *IgM in serum/CSF (detected 3-8 days after onset, persists 30-90 days)
Treatment: Supportive therapy
Vaccines:
RNA Viruses (+) sense
“FLAVIVIRUS
(flavor packed flavi)”
Dengue Fever (Type 2)
Features: “* +ssRNA
* Enveloped
* non-segmented RNA”
Reservoir/Transmission: “*Aedes mosquitoes (vector), blood transfusion, organ transplant
*Enhancing Ab: Ab to one serotype increase efficiency of infection by another”
Diseases: “Dengue / Bone-break fever (infects bone marrow)
* Dengue Fever: (3-7 days post bite) Faint macular rash that is diffuse/blanches (50%), fever, myalgias, arthralgias, headaches, retro-orbital pain, elevated AST, thrombocytopenia, hemorrhage
Dengue Hemorrhagic Fever: Shock, OD, bleeding, marked thrombocytopenia, fever 2-7d, increased vascular permeability
* Dengue Shock Syndrome
* 4 different serotypes”
Diagnosis: “ Serology
PCR”
Treatment: “ Supportive therapy
*No antiviral therapy”
Vaccines: *Vaccine exists but NOT used in travelers
RNA Viruses (+) sense
“FLAVIVIRUS
(flavor packed flavi)”
Yellow Fever
Features: “* Flavirvirus
* Councilman bodies (eosinophilic apoptotic globules) on liver biopsy (also HAV)”
Reservoir/Transmission: “*Aedes mosquitoes (Africa)
Haemagogus mosquito (S America)”
Diseases: “ Jaundice, backache, bloody stool/vomiting (black)
*Asymptomatic –> febrile –> hemorrhagic fever with jaundice, renal failure, hemorrhage
Fever, malaise, diffuse pain, nausea/vomiting, dizzy, irritable –> remits 2d –> OD on d3”
Diagnosis:
Treatment:
Vaccines: “No anti-infective therapy for travelers
* Live attenuated vaccine (IM): > 9 mo living in/traveling to high risk area (Africa, South America)”
RNA Viruses (+) sense
“FLAVIVIRUS
(flavor packed flavi)”
Chikungunya
Features:Alphavirus
Reservoir/Transmission: “ Aedes mosquito
Outbreaks during rainy seasons”
Diseases: “ High fevers, severe polyarthralgias 2-5d after (bilateral, symmetric), macular/maculopapular rash, HA, myalgias, GI symptoms
* Lab abnormalities: lymphopenia, thrombocytopenia, transaminitis, AKI”
Diagnosis:
Treatment:
Vaccines:
RNA Viruses (+) sense
“FLAVIVIRUS
(flavor packed flavi)”
Zika virus
Features: * Flavivirus
Reservoir/Transmission: “* Aedes mosquito
Only vector-born infection that is transmitted sexually (transfusion & transplant too)
* Year round transmission in tropical/subtropical regions”
Diseases: “ Febrile illness: fever (3-5d), conjunctivitis, maculopopular rash, polyarthralgia (2-5d after fever), HA (1 wk) –> persistent arthritis & arthralgia following acute illness
* Complications: resp failure, meningoencephalitis, acute hepatitis, renal failure, CV decompensation
*Post-infection GBS
In utero: microcephaly, developmental problems, abortion, opthalmologic problems”
Diagnosis: “ Serology
*Viral culture “
Treatment: * supportive therapy
Vaccines:
RNA Viruses (+) sense
“FLAVIVIRUS
(flavor packed flavi)”
“Hep C (HCV)
(the hep sea)”
Features: “Flavivirus family (+ssRNA, enveloped, non-segmented RNA)
- Antigenic variation due to lack of 3-5’ proofreading exonuclease activity in virion encoded RNA Pol”
Reservoir/Transmission: “* Blood transfusion (also in placental, sex, breast milk)
Sharing needles”
Diseases: “Cryoglobulins: serum proteins containing IgM that precipitate in cool temp - Acute hepatitis: jaundice, enlarged liver, elevated liver enzymes; viral RNA in serum for < 6 mo
*Chronic hepatitis: viral RNA persists in serum > 6 mo; liver biopsy shows lymphocytes in portal tract (60-80% of infections become chronic) - Increased risk of hepatocellular carcinoma & cirrhosis”
Diagnosis: Acute infection characterized by rise & fall in ALT by 6 mo
Treatment: “ Protease/pol inhibitors (new) - IFN-a / Ribarvirin (older treatments)
*Genotype testing should be done
“
Vaccines: * No vaccine due to antigenic variation of envelope proteins
RNA Viruses (+) sense
“FLAVIVIRUS
(flavor packed flavi)”
“TOGAVIRUS
(toga-toga-togavirus)”
Features: “* +ssRNA
* Enveloped
* Polyprotein product”
Reservoir/Transmission:
Diseases: mainly rubella
Diagnosis:
Treatment:
Vaccines:
RNA Viruses (+) sense
“Rubella
(German Measles)”
Features: “* +ssRNA
* Enveloped
* Polyprotein product”
Reservoir/Transmission: “* Resp transmission (replicates in nasopharynx & regional LNs)
* Pts w/o vaccinations (immigrants, anti-vaxers)
* Incubation period = 14-21 days”
Diseases: “Childhood Exanthem = Third Disease: Mild, usually subclinical
*Postaricular/occipital lymphadenopathy
*Maculopapular rash beginning on face (14-17 days post-exposure) + spreads down (lasts ~3 days)
* Low grade fever
*Conjunctivitis & palatal enanthem (petechia on hard palate), encephalitis, thrombocytopenia
Congenital Rubella: infection during 1/2 trimesters (later infection results in less anomalies)
*Transient symptoms: lymphadenopathy, hepatosplenomegaly, poor growth, bone marrow involvement, microcephaly, jaundice, purpuritic blueberry muffin rash (due to dermal erythropoiesis; also seen w congenital CMV)
*Permanent findings: heart (PDA, pulm arterial/valve stenosis), eye (retinopathy, cataracts, microphthalmia), brain, auditory symptoms (bilateral deafness)
* Triad: Cataracts, sensory neural deafness, PDA (I heart ruby earrings)
Adults:
* Arthritis & arthralgia (also have lymphadenopathy & fever, like children do)”
Diagnosis:
Treatment:
Vaccines: *MMR vaccine: (live attenuated) Should NOT be given to pregnant women, immunocompromised (HIV pts if CD4 < 200)
RNA Viruses (+) sense
“TOGAVIRUS
(toga-toga-togavirus)”
Eastern Equine Encephalitis
Features: “* +ssRNA
* Enveloped
* Polyprotein product”
Reservoir/Transmission: “*Insect
* N America & Caribbean
*Peak incidence Aug-Sept
Hardwood swamp areass”
Diseases: “ Encephalitis in 4-5% infections
*Highest mortality rate (50%)”
Diagnosis:
Treatment:
Vaccines:
RNA Viruses (+) sense
“TOGAVIRUS
(toga-toga-togavirus)”
Western Equine Encephalitis
Features: “* +ssRNA
* Enveloped
* Polyprotein product”
Reservoir/Transmission: “* Culex mosquito
N & S America”
Diseases: “Encephalities is RARE
*Lower fatality rate 3-7%”
Diagnosis:
Treatment:
Vaccines:
RNA Viruses (+) sense
“TOGAVIRUS
(toga-toga-togavirus)”
“CORONAVIRUS
(kingdom of SARS)”
Features: “* +ssRNA
Enveloped
* Helical capsule”
Reservoir/Transmission:
Diseases: “Common cold (2nd most common cause behind rhinovirus)
*Acute bronchitis that can progress to ARDS (diagnosed with antibody/PCR)
* MERS (middle east resp syndrome)
* SARS (severe acute resp syndrome)”
Diagnosis:
Treatment:
Vaccines:
RNA Viruses (+) sense