Viruses Flashcards

Question

Poxviridae

Answer 1

Replicate in the cytoplasm of host cell Smallpox Molluscum contagiosum - Common self-limited viral disease caused by Poxvirus look for cytoplasmic inclusions

Answer 2

Oncogenic transforming viruses: Viral E6 inhibits p53 protein and E7 inhibits pRB protein High-risk - types 16 and 18 responsible for most cancers and high grade dysplasias prevention: vaccination (females) and physical barriers

Answer 3

BK - Renal disease (failure) in AIDS or post-transplant patients Dx - BKV DNA by PCR or urine cytology with decoy cells (basophilic nuclear inclusions) JC - Progressive multifocal leukoencephalopathy in AIDS or post-transplant Dx - JCV DNA by PCR

Answer 4

Acute respiratory disease – serotypes 4,7 &21) upper respiratory infections in kids/young adults that can progress to pneumonia Gastroenteritis - adenoviruses that lead to diarrhea Pharyngoconjunctivitis – pink eye and sore throat Prevention – live adenovirus vaccine

Answer 5

Parvovirus B19 Naked ssDNA in segments (some positive, others negative) Erythema infectiosum (fifth disease) Fever, arthralgias and cheek rash children Aplastic anemia (infects erythroblasts) Can cause hydrops fetalis via in utero infection

Answer 6

Western/ Eastern Equine Encephalitis (alpha virus) Lt. Louis encephalitis virus (flavivirus) --> St Louis encephalitis West Nile virus (flavivirus) Dengue virus (flavivirus) Colorado tick fever virus (reovirus) --> headaches behind the eyes, photophobia, rash La Cross virus (bunyavirus) Other viruses that can cause encephalitis: HSV, VZV, Influenza, Enteroviruses, Rabies, Mumps, Measles

Answer 7

Arthropod borne viruses Togaviridae: WEE, EEE, VEE encephalitis, chikungunya & rubella Flaviviradae Yellow and dengue fevers, St. Louis and Japanese encephalitis, West Nile virus, hepatitis C Bunyaviradae California encephalitis, Rift Valley fever, hantavirus

Answer 8

Alphaviruses Chikungunya: get viremia with acute febrile illness with malaise, rash and arthritis Eastern and western equine encephalitis (EEE, WEE) ``` Rubivirus (no arthropod vector) – rubella (German measles) Congenital rubella (TORCH syndrome) ``` Flaviviruses (more to follow) Yellow fever virus, Dengue virus, St. Louis encephalitis, Japanese encephalitis, West Nile virus, hepatitis C virus Bunyaviruses California encephalitis, Rift Valley fever, pappataci (sandfly) fever, hantavirus pulmonary syndrome (more in emerging pathogens slides)

Answer 9

= German measles Congenital rubella syndrome affects the eyes, heart and brain Infection occurred during 1st trimester of pregnancy

Answer 10

Flaviviruses Mosquitoes St. Louis encephalitis (SLE): viremia (usually asymptomatic), in some CNS involvement causes encephalitis inflammation and neuronal degeneration West Nile encephalitis (WNE): viremia (usually asymptomatic), mild, flu-like cases ("West Nile fever“), more severe "West Nile encephalitis" or "West Nile meningitis" which can lead to death Yellow fever: viremia with severe systemic disease (fever, headache, nausea and vomiting) followed by liver damage and intestinal hemorrhages (jaundice, shock and death) Dengue fever: virus replicates in the skin and then goes to lymphoid tissue followed by a viremia which results in fever and rash lasting 3-9 days (self-limited) but can get dengue hemorrhagic fever (immunopathologic processes produce extreme vascular permeability, shock and death and associated with serotype 2)

Answer 11

Heparnavirus – discussed with hepatitis viruses Rhinoviruses - Attach via ICAM-1 receptor to respiratory epithelial cells Enteroviruses (Poliovirus, Coxsackievirus, Echovirus, etc.) - spread fecal-oral

Answer 12

Polioviruses Prevention- Inactive (Salk vaccine), oral (Sabin vaccine) Coxsackie A & B can cause aseptic meningitis. A Group A - herpangina, acute hemorrhagic conjunctivitis & hand-foot-and-mouth disease Group B - pleurodynia, myocarditis, pericarditis, and hepatitis Echoviruses

Answer 13

bullet-shaped (think: shoot the rabid dog) (encephalitis) via acetylcholine receptor with retrograde axoplasmic transport to dorsal root ganglia and spinal cord Negri bodies (Neurons accumulate ribonucleoprotein as intracytoplasmic inclusions) hydrophobia, anxiety, dilation of pupils Once symptomatic death is almost certain despite optimal supportive care Prevention: vaccines for dogs and cats

Answer 14

cholera, cryptosporidiosis, Ebola hemorrhagic fever, dengue fever, hantavirus pulmonary syndrome, hep C, HIV/ AIDS, influenza, legionnaires' disease and Pontiac fever, malaria, MRSA, SARS, VISA/ VRSA, Staph aureus, West Nile virus Of Biodefense importance: Ehrlichiosis, Hep C and E, among many others.

Answer 15

not polio, but polio-like acute flaccid myelitis, new outbreak in US 2014-2015 Appears to be related to enterovirus 68

Answer 16

Appears to be associated with development of Guillain-Barré syndrome Appears to be associated with microcephaly, lissencephaly and other neurologic malformations with in utero infections (highest risk in second trimester) Vector is aedes mosquito species

Answer 17

RNA viruses Arenaviridae – South American hemorrhagic fever viruses and Lassa Fever Filoviridae – Ebola (4 subtypes) and Marburg viruses Bunyaviridae – Rift Valley fever & Crimean-Congo hemorrhagic fever Flaviviridae – Dengue hemorrhagic fever Rhabdoviridae – Bas-Congo virus hemorrhagic fever usually insect vector

Answer 18

Person-to-person transmission via blood or body fluids (urine, saliva, sweat, feces, vomit, breast milk, and semen) Symptoms appear 2 to 21 days after exposure 25-90% mortality

Answer 19

Classic dengue fever, “break bone fever,” - acute onset of high fever 3–14 days after the bite, frontal headache, retro-orbital pain, myalgias, arthralgias, hemorrhagic manifestations, rash, and low white blood cell count Dengue hemorrhagic fever - Fever lasting 2–7 days with any hemorrhagic manifestation, thrombocytopenia, evidence of increased vascular permeability. Can have severe abdominal pain, CNS symptoms, shock. RX- supportive, IV fluids, Dextran 40

Answer 20

Tick (Ixodes) borne virus found mostly in Canada, northeast and Great Lakes regions, and Russia 1 week to 1 month incubation and infections range from asymptomatic to encephalitis and meningitis Fever, headache, vomiting, weakness, confusion, loss of coordination, speech difficulties, and seizures 50% develop permanent neurologic deficits 10% die

Answer 21

Vector - mosquito (lots of different species) Human to human via blood or milk Acute viremia Usually subclinical infections or viral syndrome (20%) Maculopapular rash in 50% with viral syndrome Meningoencephalitis (

Answer 22

Symptoms begin 3–7 days after being bitten by infected Aedes mosquitos ``` Most common symptoms are fever and joint pain Self limited (1 wk. most symptoms and months for joints) ```

Answer 23

Severe acute atypical respiratory syndrome due to a novel coronavirus No cases since 2003 outbreak

Answer 24

Middle East Respiratory Syndrome Coronavirus Asymptomatic to severe acute respiratory syndrome (fever and pneumonia) in person coming from Arabian peninsula or in close contact with MERS patient Spread via saliva, respiratory droplets

Answer 25

California encephalitis- California encephalitis virus via mosquitos in Kern and Marin counties, CA La Crosse encephalitis- La Crosse virus via mosquitos in Eastern U.S. Hantavirus – worldwide Hemorrhagic fever with renal failure – Asia and Europe Pulmonary syndrome - spread via aerosolized rodent excrement causing pulmonary edema with 40% mortality; in U.S. around “four corners” region (Arizona, Colorado, New Mexico and Utah) Deer mice is carrier in Four Corners region serology to “Sin Nombre” virus; p.k.a “Four Corners virus”

Answer 26

Ubiquitous soil bacteria that also live in the gut of Anopheles gambiae mosquitos Can colonize human respiratory tract E. anopheles 2015-16 community acquired outbreak from unknown source in debilitated elderly around Milwaukee, Wisconsin has killed 15 (of 52 patients) as of March, 2016

Answer 27

Category A - can be easily disseminated or transmitted from person to person; result in high mortality - anthrax, smallpox (variola major), Viral hemorrhagic fevers (arenaviruses, bunyaviruses - hantaviruses, rift valley fever, crimean congo hemorrhagic fever, flaviruses- dengue, filoviruses- ebola & marburg) Category B - moderately easy to disseminate; result in moderate morbidity rates and low mortality rates; - Brucellosis (brucella species), Ricin toxin, water safety threats (vibrio cholerae, e.g.) Category C - emerging pathogens that could be engineered for mass dissemination. Emerging infectious diseases such as Nipah virus and hantavirus. SARS and MERS.

Answer 28

Rx- 3 concurrent antimicrobials Anthrasil (anthrax immune globulin intravenous [human]) for inhalational anthrax vaccine: Ava/BioThrax (used for combatants)-

Answer 29

Smallpox Variola virus Respiratory transmission Dx –Characteristic deep skin lesions with centrifugal pattern (mostly face and extremities) and synchronous development on individual areas of the body Smallpox vaccine – live vaccinia virus preparation