Viruses Flashcards
Herpes virus
Enveloped
DS + Linear DNA
Poxvirus
Enveloped
DS + Linear (biggest) DNA
Molluscum contagiosum (papule with central umbilication)
Hepadnavirus
Enveloped
Partially DS + Circular DNA
HBV (acute or chronic hepatitis, virus has a reverse transcriptase)
Adenovirus
DS + Linear DNA
Febrile pharyngitis (sore throat)
Conjunctivitis
Acute hemorrhagic cystitis
Pneumonia
Gastroenteritis
Myocarditis
Papillomavirus
DS + Circular DNA
HPV
- Warts (serotypes 1,2,6,11)
- Cancer (cervical, penile, anal etc serotypes 16, 18)
Polyomavirus
“Junky Cerebrum, Bad Kidney”
DS + Circular DNA
JC virus (Progressive multifocal leukoencephalitis in HIV)
BK virus (Kidney failure in transplants)
Parvovirus
SS + Linear (smallest) DNA
B19
- 5th disease/ Erythema Infectiosum, SCS
- Aplastic crisis in Sickle Cell Disease
- Hydrops fetalis (destroyed RBC precursors)
HSV1
Trans via respiratory droplets & saliva
Latent in Trigeminal ganglion
Causes:
Gingivostomatitis
Keratoconjunctivitis
Cold sores
Herpetic whitlow
Temporal lobe encephalitis
Esophagitis
Erythema multiforme
HSV2
Trans via sexual contact
Latent in Sacral ganglion
Genital herpes
Neonatal herpes
VZV (varicella zooster virus) HHV3
Trans via respiratory droplets & vesicle fluid
Latent in trigeminal or dorsal root ganglion
Chicken pox (all over)
Shingles (one dermatome)
Encephalitis
Pneumonia
EBV (Epstein Barr virus) HHV4
“must be 21 to drink Beer at a Barr”
Trans via respiratory droplets & saliva (Kissing disease)
Mononucleosis (monospot +, heterophile +, & Ab agglutination in sheeps blood)
Infects B cells via CD21
Fever hepatosplenomegaly
Pharyngitis
Lymphadenopathy
Nasopharyngeal carcinoma (asians)
Treating with amoxicillin = maculopapular rash
CMV (Cytomegalovirus) HHV 5
Trans via sex, urine, transfusions, or congenitally
Mononucleosis-like syndrome (monospot & heterophile -)
in AIDS & transplant patients
OWL eye inclusions & lies latent in mononuclear cells
Esophagitis
Cotton-wool exudates
Vison loss
Congenital CMV
HHV6-7
&
HHV8
6-7: picture I
Trans via saliva
Roseola infantum
First fever several days then macular rash (starting at trunk & spreading to arms/legs)
8: picture J
Trans via sex
Kaposi sarcoma in HIV/AIDS & transplant patients (dark/violaceous plaques/nodules)
ID HSV (4)
PCR skin lesion
CSF PCR (Herpes encephalitis)
Tzank smear (Multinucleated giant cells)
Intranuclear Cowdry A inclusions
Receptors for:
CMV
Integrins (heparan sulfate)
Receptors for:
EBV
CD21
Receptors for:
HIV
CD4, CXCR4, CCR5
Receptors for:
Parvovirus B19
P antigen on RBC’s
Receptors for:
Rabies
Nicotinic AChR
Receptors for:
Rhinovirus
ICAM 1
Reovirus
DS + Linear multisegmented RNA
Icosahedral
Coltivirus (Colorado tick fever)
Rotavirus (Fatal diarrhea in kids)
Picornavirus
“PERCH”
SS + Linear RNA
Icosahedral
Poliovirus
Echovirus
Rhinovirus
Coxsackie virus
HAV
Hepevirus
SS + Linear RNA
Icosahedral
HEV
Calicivirus
SS + Linear
Icosahedral
Norovirus (Viral gastroenteritis)
Flavivirus
Enveloped
SS + Linear RNA
Icosahedral
HCV
Yellow fever
Dengue
St. Louis encephalitis
West Nile virus (meningoencephalitis + flaccid paralysis)
Zika
Togavirus
“CREW”
Enveloped
SS + Linear RNA
Icosahedral
Chikungunya virus
Rubella
Easter/Western equine encephalitis
Retrovirus
Enveloped
SS + Linear (with 2 copies) RNA
Have a reverse transcriptase
Icosahedral (HTLV= T cell leukemia)
Conical (HIV = AIDS)
Coronavirus
Enveloped
SS + Linear RNA
Helical
SARS
MERS
Covid 19
Orthomyxovirus
Enveloped
SS + Linear RNA in 8 segments
Helical
Influenza
Paramyxoviruses
(childhood viruses)
Enveloped
SS + Linear RNA Non-segmented
Helical
Parainfluenza
RSV (Croup)
Measles
Mumps
Rhabdovirus
Enveloped
SS - Linear RNA
Helical
Rabies
Filovirus
Enveloped
SS - Linear RNA
Helical
EBOLA
Marburg hemorrhagic fever
Arenaviruses
Enveloped
SS +/- Circular RNA in 2 segments
Helical
LCMV (Lymphocytic Choriomeningitis virus)
Lassa fever encephalitis (Rodents)
Bunyaviruses
Enveloped
SS - Circular RNA in 3 segments
Helical
California encephalitis
Sandfly/Rift valley fever
Crimean-Congo hemorrhagic fever
Hantavirus (hemorrhagic fever & pneumonia)
Deltavirus
Enveloped
SS - Circular RNA
HDV (needs HBV to replicate)
Negative stranded viruses
Need to transcribe their negative RNA to positive
they bring their own RDRP
Arenavirus
Segmented RNA viruses
“BOARding flight 382 in 10-12 minutes”
Bunyavirus (3 segments)
Orthomyxovirus (8 segments)
Arenavirus (2 segments)
Reovirus (10-12 segments)
PircoRNAvirus
“Small RNA viruses PERCH “
Poliovirus
Echovirus
Rhinovirus
Coxsackie virus
HAV
All are main causes of Aseptic meningitis
Rhinovirus
A picornavirus
NON-Enveloped
100+ Serotypes causing the common cold
Acid labile (can’t infect the GI)
Rotavirus
A reovirus
Segmented DS RNA
Infantile gastroenteritis (destroys villi causing less Na absorption and loss of K+) aka diarrhea.
Influenza
An orthomyxovirus
Enveloped
SS - RNA with segments
Hemagglutinin (binds sialic acid and lets virus in)
Neuraminidase (prompts progeny release)
Influenza can be superinfected with which 3 viruses
S.aureus S. pneumoniae, & H.influenza
Influenza treatment
Oseltamivir & Zanamivir
(+/- Neuraminidase inhibitor)
Influenza vaccine
Killed and live attenuated (nasal only)
Influenza
Genetic Shift vs Drift
Shift:
2 different strains (swine + human) infect the same cell and recombine their RNA to make major changes causing a new variant (can cause PANDEMICS)
Drift:
Random hemagglutinin or neuraminidase protein/gene mutations that cause minor changes to a strain (can cause EPIDEMICS)
Rubella
A togavirus
Rubella/German Measles:
Fever, postauricular/lymphadenopathy, arthralgias, fine maculopapular rash (that starts at the face & spreads to the trunk then extremities)
mild in kids
severe congenital
Congenital Rubella
A severe TORCH syndrome
Deafness, Cataracts, Patent ductus arteriosus, Blueberry muffin rash appearance
Paramyxoviruses
Parainfluenza (croup)
Mumps
Measles
RSV
Human metapneumovirus z
All have F (fusion) surface proteins that cause respiratory epithelium to fuse forming multinucleated cells causing bronchiolitis & pneumonia
Treating Paramyxoviruses
Palivizumab (monoclonal antibody against F proteins)
Croup
aka acute laryngotracheobronchitis
presents with a seal bark cough & steeple sign on X-RAY
Measles
Prodromal fever + cough
Coryza, Conjunctivitis, Koplik spots (bright red spots with blue-white center in mouth)
Lymphadenitis with Warthin-Finkeldey Gian cells
Measles sequelae
Subacute sclerosing panencephalitis
Encephalitis
Giant cell pneumonia
Reduces Measles morbidity
Vitamin A supplements
Mumps
“mumps make your testes the size of POM PomS”
Parotitis
Orchitis
aseptic Meningitis
Pancreatitis
Sterility
Chikungunya virus
Togavirus (alphavirus)
Trans via aedes mosquito
Systemic infection (inflammatory polyarthritis, high fever, maculopapular rash, headache, & lymphadenopathy)
Diagnosis test for Chikungunya
RT-PCR & Serology
Dengue fever
Flavivirus
Trans via aedes mosquito
Dengue fever (fever, myalgia, rash, headache, arthralgias, & neutropenia)
Dengue Hemorrhagic fever (Dengue fever & thrombocytopenia)
Dengue Shock ( Circulatory collapse)
Dengue fever test & treatment
test:
PCR/Serology
Rx. Live recombinant vaccine
Rabies
Bullet shaped virus
Negri bodies usually in Purkinje cells of cerebellum & hippocampal neurons
Weeks to months IP
It travels to the CNS via retrograde (dynein) after binding ACh receptors causing fever, malaise –> agitation, photo/hydrophobia, & hypersalivation –> Paralysis, coma, & death
Treating Rabies
Post exposure prophylaxis with killed vaccine & rabies immunoglobin
Yellow Fever
A flavivirus
Trans via aedes mosquitos
High fever, black vomitus, jaundice, hemorrhages, backaches, & Councilman bodies in the liver
Ebola
A filovirus
21-day IP period
Abrupt onset of flu symptoms, diarrhea/vomiting, high fever, myalgia, & progressive diffuse hemorrhagic shock
Ebola test
RT-PCR within 48hrs
Zika virus
A flavivirus
Trans via aedes mosquito
Conjunctivitis, low-grade pyrexia, & itchy rash
Congenital Zika
Can end up in miscarriage or congenital Zika.
Ventriculomegaly, Subcortical calcifications, microencephaly, ocular abnormalities, spasticity, & seizures
Common symptoms of all Hepatitis infections
Naked viruses that cause
Fever, Jaundice, High ALT/AST
HAV (Hepatitis A)
A picornavirus (RNA)
Trans via fecal-orally (shellfish)
Acute & self limiting (adults)
Asymptomatic (kids)
No hepatocellular carcinoma risk
No carrier state
HBV (Hepatitis B)
A hepadnavirus (DNA)
Trans via Parentally (Blood/Sex) & Perinatally (Birthing)
Initially like serum sickness (fever, arthralgia, rash, which may progress to carcinoma)
Adults (usually resolves)
Neonates (worse)
High risk of Hepatocellular carcinoma
Common carrier state
HBV (Hepatitis B) Liver biopsy shows
Granular eosinophilic “ground-glass opacities” that are the accumulation of surface antigens in infected hepatocytes
(CD8 mediated damage)
HCV (Hepatitis C)
A flavivirus (RNA)
Trans via (Blood, IV drugs, or post transfusions)
May progress to cirrhosis or carcinoma
Majority develop stable chronic hep C
High risk for hepatocellular carcinomas
Carrier state is common
HCV (Hepatitis C) Liver Biopsy
Lymphoid aggregates with focal areas of macrovesicular steatosis
HDV (Hepatitis Delta)
A deltavirus (RNA)
Trans via Blood/Sex/Perinatally
Superinfection (HDV after HBV) = short infection
Coinfection (HDV with HBV) = long infection
May progress to cirrhosis or carcinoma
High hepatocellular carcinoma risk
HDV needs HBV’s HBsAg coat to enter hepatocytes
HDV (Hepatitis Delta) Liver biopsy
Lymphoid aggregates with focal areas of macrovesicular steatosis
HEV (Hepatitis E)
A hepevirus (RNA)
Trans via Fecal-oral (waterborne)
Fulminant hepatitis in pregnant patients (higher mortality)
No hepatocellular carcinoma risk
No carrier states
HEV (Hepatitis E) Liver biopsy
Patchy necrosis
Extrahepatic manifestations of HBV
Aplastic anemia
Membranous Glomerular nephritis
Polyarthritis
Extrahepatic manifestations of HCV
Essential mixed cryoglobulinemia
High risk of B cell non-Hodkin lymphoma
Autoimmune hemolytic anemia
Membranoproliferative Glomerular nephritis
Leukocytoclastic vasculitis
Sporadic porphyria cutanea tarda
Lichen planus
High risk of diabetes mellitus
Auto immune hypothyroidism
Hepatitis serology markers:
Anti-HAV (IgM)
Anti-HAV (IgG)
Acute HAV
A prior HAV infection or vaccination (protects against reinfection)
Hepatitis serology markers:
HBsAg
Anti-HBs
HBV infection
Vaccination or recovery from infection indicates immunity
Hepatitis serology markers:
HBc-Ag
Anti-HBc (IgM or IgG)
Core HBV
IgM = acute/recent infection
IgG = Chronic/prior infection
Hepatitis serology markers:
HbeAg
Anti-HBe
Active viral replication + high transmissibility
Low transmissibility
Acute HBV infection Serology markers
HBsAg
HBeAg
Anti-HBc IgM
Window HBV infection Serology markers
Anti-HBe
Anti-HBc IgM
Chronic with high transmissibility HBV infection Serology markers
Anti-HBc IgG
HBeAg
HBsAg
Chronic with low transmissibility HBV infection Serology markers
Anti-HBc IgG
Anti-HBe
HBsAg
Recovery HBV infection Serology markers
Anti-HBc IgG
Anti-HBs
Anti-HBe
Immunized HBV infection Serology markers
Anti-HBs
HIV 3 structural genes
env:
gb120 (attaches to host CD4 + Tcell)
gb41 (fusion + entry)
gag:
p24 (capsid protein)
p17 (matrix protein)
pol:
Reverse transcriptase (makes DS DNA from RNA)
Integrase (DS DNA is integrated into host’s genome)
Protease (Virus binds CD4 & a coreceptor either CCR5 (Macrophages in early inf) or CXCR4 (T cells in late inf)
Homozygous CCR5 = Immune
Heterozygous CCR5 = Slower disease course
Diagnosing HIV
HIV 1/2 Ag/Ab immunoassay
Detecting P24 Ag capsid protein & IgG Abs to HIV 1/2
AIDs Defining conditions:
CD4 <500
Candida albicans (oral thrush, a scrapable white plaque with pseudohypae on microscopy)
EBV (Oral hairy leukoplakia, an Un scrapable white plaque on tongue)
HHV8 (Kaposi sarcoma, perivascular spindle cells invading & forming vascular tumors)
HPV (Squamous cell carcinoma)
AIDs Defining conditions:
CD4 <200
Histoplasma (fever, weight loss, fatigue, cough, dyspnea, nausea, vomiting, & diarrhea, oval yeast cells in macrophages)
HIV (Dementia, cerebral atrophy)
JC virus (Progressive multifocal leukoencephalopathy, non-enhancing areas of focal demyelination on MRI)
Pneumocystis jirovecii (Pneumocystis pneumonia with ground-glass opacities on chest imaging)
AIDs Defining conditions:
CD4 <100
Aspergillus fumigatus (Hemoptysis, pleuritic pain, with cavitation on infiltrates on chest imaging)
Bartonella spp (Bacillary angiomatosis, Mutiple red-purple papules/nodules, biopsy with neutrophilic inflammation)
Candida albicans (esophagitis, white plaques on endoscopy with yeast + pseudohyphae on biopsy)
CMV (Colitis, Retinitis, Esophagitis, Encephalitis, Pneumonitis with Linear ulcers on endoscopy, cotton-wool spots on fundoscopy, & owl eye inclusions in biopsy)
Cryptococcus neoformans (Meningitis, with encapsulated yeast on Indian ink stain or capsular Ag +)
Cryptpsporidium spp (Chronic watery diarrhea with acid fast oocysts in stool)
EBV (B cell lymphoma showing ring enhancing lesions)
Mycobaterium avium intracellulare & complex (fever, night-sweats, weight loss or focal lymphadenitis, & risk of toxoplasma gondii infection)
Prion diseases are due to
A mutation causing a helix PrPc to convert to B-pleated PrPsc, which accumulate in CNS causing spongiform encephalitis, dementia, & ataxia
CJD (Creutzfeldt-Jakob disease)
Spongiform encephalopathy causing rapidly progressive dementia
BSE
Bovine Spongiform encephalopathy aka Mad cow disease
Kuru
Acquired prion disease noted in tribes that practice cannibalism
Normal dominant flora:
Skin
Nose
Oropharynx
Dental plaque
Colon
Vagina
Skin = S. epidermidis
Nose = S. epidermidis, colonized s. aureus
Oropharynx = Viridians group streptococci
Dental plaque = S. mutans
Colon = B. fragilis + E.coli
Vagina = Lactobacillus, colonized E.coli + group B streptococci
Bacillus cereus infection is from
Re-heated rice
C. botulinum infection is from
Improperly canned food (toxins) or raw honey (spores)
C. perfringes infection is from
Re-heated meat
E.coli 0157:H7
Undercooked meat
L. monocytogenes
Deli meats + soft cheese
Salmonella
Poultry + eggs
S. aureus
Meat, mayo, custard, preformed toxin
V. parahaemolyticus & V. vulnificus
Raw/undercooked seafood
Major causes of bloody diarrhea (infections)
Campylobacter
E. histolytica
Enterohemorrhagic E.coli
Enteroinvasive E.coli
Salmonella (non-typhi)
Shigella
Y enterocolitica
Major causes of watery diarrhea (infections)
C. difficile
C. perfringes
Enterotoxigenic E.coli
Giardia
Cryptosporidium
V. cholerae
Norovirus
Rotavirus
Enteric adenovirus
Major causes of pneumonia (infections):
Neonates
Children
N:
Group B streptococci
E.coli
C:
RSV
Mycoplasma
C. trachomatis
C. pneumoniae
S. pneumoniae
Major causes of pneumonia (infections):
Adults
Elderly
A:
Mycoplasma
C. pneumoniae
H. influenza
Anaerobes
E:
S. pneumoniae
Influenza
Anaerobes
Gram neg rods
Common infections with Alcohol use
Klebsiella
Anaerobes
Common infections with IV drugs
S. pneumoniae
S. aureus
Common infections causing meningitis
S. agalatiae
E.coli
Listeria monocytogenes
Bacterial CSF
High opening pressure
Elevated PMN cells
Elevated proteins
Low glucose
Fungal/TB CSF
High opening pressure
Elevated lymphocytes
Elevated proteins
Low glucose
Viral CSF
Normal or high opening pressure
Elevated lymphocytes
Normal or high proteins
Normal glucose
Bacterial vaginosis
Gardnerella vaginalis
No inflammation & thin white discharge with a fishy smell
Clue cells
Positive KOH Whiff test
Lower pH (below 4.5)
Treat Gardnerella vaginalis
Metronidazole or clindamycin
Trichomonas vaginitis
Inflammation (Strawberry cervix)
Frothy, yellow-green, & foul-smelling discharge
Motile pear-shaped trichomonads
Low pH (below 4.5)
Treat Trichomonas vaginitis
Metronidazole
Candida albicans
Inflammation
Thick-white “cottage-cheese” discharge
Pseudohyphae
Normal pH (4-4.5)
Treating Candida albicans
Azoles
TORCH
Toxoplasma gondii
Trans via cat poop or undercooked pork
Neonates:
chorioretinitis
hydrocephalus
intracranial calcifications
Blueberry muffin rash
TORCH
Rubella
Trans via respiratory droplets
Mom:
Rash, lymphadenopathy, pharyngitis, polyarthritis
Neonate:
Cataracts, deafness, congenital heart disease, Blueberry muffin rash
TORCH
CMV (Cytomegalovirus)
Trans via sex/transplants
Mom: Asymptomatic or mononucleosis-like illness
Neonate: Hearing loss, seizures, Blueberry muffin rash, chorioretinitis, periventricular calcifications
TORCH
HIV
Trans Sex/needle stick
Mom= variable
Neonate= Recurrent infections & chronic diarrhea
TORCH
Herpes Simplex Virus 2
Trans Skin/mucous membranes
Mom: Genital herpes
Neonate: Meningoencephalitis, herpetic vesicular lesions
TORCH
Syphilis
Trans Sex
Mom: Chancre & disseminated rash
Neonate:
Death via still birth or hydrops fetalis
Survived causes facial defects, saber shins, & VIII deafness
VZV (Varicella Zooster virus)
Chicken pox (Vesicular rash starts on the trunk & spreads to face/extremities with lesions at different stages)
Coxsackie A
Hand-foot-mouth disease (Oval-shaped vesicles on palms/soles; with vesicles + ulcers in the oral mucosal (herpangina))
HHV6
Roseola (exanthem subitum)
Asymptomatic rose colored macules on the body after a several day long fever with febrile seizures (usually infants)
Measles virus (Rubeola)
Confluent rash (starts at the head & moves down) then cough, coryza, conjunctivitis, & Koplik spots (blue-white spots on the mouth mucosa)
Parvovirus B19
Erythema infectious (5th disease) slapped cheek syndrome on the face.
&
Hydrops fetalis in pregnant patients
Rubella virus
Rubella (pink macules & papules (that start at the head and move down as a fine desquamating truncal rash, & post auricular lymphadenopathy)
Streptococcus pyogenes “SCARLET”
Scarlet fever”
Sore throat
Circumoral pallor
group A streptococci
Rash
Lymphadenopathy
Erythrogenic toxin
strawberry Tongue
Sexually transmitted infections:
HIV
AIDS (Opportunistic infections, Kaposi’s sarcoma, & lymphoma)
Sexually transmitted infections:
Haemophilus ducreyi
(do cry)
Chancroid (a painful genital ulcer with exudate & inguinal adenopathy)
Chlamydia trachomatis (D-K)
Chlamydia (urethritis, cervicitis, epididymitis, conjunctivitis, reactive arthritis, & PID)
