Chapter 18 Flashcards
1
Q
how do viruses cause diseases
A
- multiply within host cells
- they escape from host cells by lysis or budding which destroys host cells
- cell destruction leads to symptoms
2
Q
cold sores
A
- usually caused by HSV1 but can be caused by HSV2
- viruses target mucous membranes
- fever blisters, herpes labialis
3
Q
anogenital herpes
A
- genital herpes
- usually caused by HSV2 but can be caused by HSV1
4
Q
herpes simplex 1
A
cold sores
5
Q
herpes simplex 2
A
genital herpes
6
Q
varicella zoster (human herpes virus 3)
A
chickenpox and shingles
7
Q
chickenpox
A
- acute, generalized viral infection with fever and skin rash
- mild and self limiting
- can severely damage fetus
- leading cause of vaccine-preventable death in US
8
Q
chickenpox fetal complications
A
- pneumonia, secondary bacterial infections, hemorrhagic complications, and ecephalitis
9
Q
reye syndrome
A
- severe encephalomyelitis with liver damage
- may follow chickenpox if aspirin is given to children younger than 16
10
Q
shingles
A
- herpes zoster
- inflammation of sensory ganglia of cutaneous sensory nerves, producing fluid filled blisters, pain, and paresthesia
- most common after 50
- reactivation of varicella virus, often result of immunosuppression
11
Q
measles
A
- acute, highly communicable viral disease with fever, conjunctivitis, cough, photosensitivity, kopek spots in mouth, red blotchy skin rash
- rash begins on days 3-7 on face then becomes generalized
- complications include bronchitis, pneumonia, otitis media, and encephalitis
12
Q
German measles (rubella)
A
- mild, febrile viral disease
- a fine pink flat rash begins 1-2 days after onset of symptoms
- rash starts on face and neck and spreads to trunk, arms, and legs
- milder than hard measles with less complications
- first trimester complication
13
Q
first trimester rubella complication
A
- if acquired in first trimester it cause cause congenital rubella syndrome in fetus
- can lead to intrauterine death, spontaneous abortion, or congenital malformations of major organ systems
14
Q
warts
A
- papilloma virus
- 70 different types of HPV
- DNA virus
- transmission by direct contact
15
Q
genial warts
A
- genital papillomatosis, condyloma acuminatum
- HPV, DNA
- transmission occurs via direct contact, usually sexual
- can become malignant
16
Q
monkey pox
A
- transmission from animals
- rare viral disease causing fever, headache, muscle aches, backache, lymphadenitis, malaise, and rash
17
Q
various minor/major
A
- causes smallpox
- double stranded DNA enveloped
- humans only known source, droplet spread or skin inoculation
- systemic viral infection with fever, malaise, headache, prostration, severe backache, skin rash and occasional abdominal pain and vomiting
- potential for biological warfare and bioterrorism
- variola minor fatality rate of <1%
- variola major fatality rate of 20-40%
- contagious before eruption of rash
- eradicated in 1980
18
Q
keratoconjuntivitis
A
- caused by types of adenovirus and herpes simplex and varicella zoster
- acute viral disease of one or both eyes
- inflammation of conjunctiva, deem of eyelids and periorbital tissue, pain, photophobia and blurred vision
19
Q
hemorrhagic conjunctivitis
A
- caused by adenovirus and enterovirus
- viral disease with sudden onset with redness, swelling, and pain in one or both eyes
- small discrete subconjunctival hemorrhages may enlarge to form confluent subconjunctival hemorrhages
20
Q
colds
A
- 200 different viruses
- one cold doesn’t protect from another
- sore throat, runny nose, sneezing, nasal congestion, headache
- sometimes muscle aches and fatigue
- no vaccine
21
Q
influenza
A
- several viruses
- protection gained from individual strains
- high fever, chills, cough, headache, muscle aches, extreme fatigue
- sometimes sore throat, runny nose, vomiting, and diarrhea
- vaccines offer some protection
22
Q
the common cold
A
- acute viral rhinitis, acute coryza
- many different viruses
- rhinoviruses are major cause in adults, more than 100 serotypes
- coronavirus, parainfluenza virus, respiratory syncytial virus, influenza virus, adenovirus, enterovirus
- transmission via respiratory secretions by hands and fomites or direct contact
- viral infection of lining of nose, sinuses, throat, and large airway
- secondary bacterial infections may follow
23
Q
acute febrile viral respiratory disease
A
- cause by parainfluenza virus, respiratory syncytial virus, adenovirus, rhinovirus, certain coronaviruses, coxsackie viruses, and echoviruses
- transmission via direct oral contact or droplets
- fever and one of following: chills, headache, general aching, malaise, anorexia, GI disturbances
- may include rhinitis, pharyngitis, tonsillitis, laryngitis, bronchitis, pneumonia, conjunctivitis, otitis media, sinusitis
- RSV is major viral respiratory tract pathogen of early infancy and it may cause pneumonia, croup, bronchitis, otitis media, and death
24
Q
influenze viruses, flu
A
- types A, B, and C
- singel stranded RNA
- acute viral respiratory infection
- transmission via infected humans, pigs, birds; airborne spread or direct contact
- fever, chills, headache, aches, pains, sore throat, cough, nasal drainage
- sometimes bronchitis, pneumonia, and death
- nausea, vomiting, and diarrhea in children
25
influenza A
- cause severe symptoms and associated with pandemic and sever disease and more localized outbreaks
26
influenza C
usually does not cause epidemics or significant disease
27
hantavirus pulmonary syndrome
- cause by 5 different hantaviruses
- transmission by inhalation of aerosolized rodeo faces, urine, and saliva
- no person to person
- fever, malaise, GI complaints, cough, difficulty breathing, hypotension
- hemorrhagic fever and renal syndrome
- 40% won't recover
- 1-12% with hemorrhagic fever with renal syndrome won't recover
28
HPS different hantaviruses
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29
avian flu
- avian influenza type A (H5, H7, H9)
- bird to human transmission via contact with infected poultry or contaminated surfaced
- future concern with person to person transmission
- respiratory infection with influenza like symptoms to eye infections, pneumonia, acute and sever respiratory distress, and other life threatening complications
30
severe acute respiratory syndrome (SARS)
- SARS associated coronavirus, ssRNA, enveloped
- high fever, chills, headache, discomfort, body aches, dry cough, pneumonia, sometimes diarrhea
- transmission via respiratory droplets, or by toughing mouth nose or eye after contaminated surface
- 2003 outbreak infected 8098 ppl and killed 774
- no cases since 2004
31
H1N1
- swine flu
- novel influenza A virus
- pandemia in 2009, most common cause of influenza that ear, 1400 deaths worldwide
- transmission by droplet and direct contact
- fever, cough, sore throat, body aches, headache, chills, fever
- vaccine available
- pigs can be infected with human, bird and pig viruses can undergo genetic recombination
32
viral gastroenteritis
- viruses infecting children and adults are norovirus like viruses and rotavirus
- transmission by fecal oral route possibly from contaminated water or shellfish
- nausea, vomiting, diarrhea, abdominal pain, myalgia, headache, malaise, fever
- self limiting 24-48 hrs
33
most common viruses of gastroenteritis infecting chidden in 1st year of life
- adenoviruses, astroviruses, caliciviruses, and rotaviruses
| - can be fatal in young children
34
family calciviridae (gastroenteritis)
- Norwalk virus (norovirus)
- transmission through oral fecal route
- self limiting gastroenteritis with typical s&s
- young, elderly, and blood type O most susceptible
- treatment is supportive, rehydration
- post infection immunity is weak and temporary
35
family piconaviridae (gastroenteritis)
- enterovirus
- > 100 viruses from mild cold like symptoms to near problems
- transmission via respiratory droplet, direct contact, decal oral route
- no specific treatment, vaccines, or antivirals
36
enterovirus D68
- seasonal respiratory illness
| - infants and children most susceptible
37
coxsackievirus B
- causes dukes disease via oral fecal route
- exanthema (skin rash presenting with fever), nausea, vomiting, and diarrhea
- infections are seasonal
- children under 5 most susceptible
- highly contagious
- mostly asymptomatic but may cause mild respirator y illness, hemorrhagic conjunctivitis, hepangina
38
rotavirus
- vaccine development underway
- human milk that contains antibody is effective when given orally to treat immunodeficient pts with chronic infection
- virus specific drugs not available
39
diarrhea
- when it is resulting from an infectious disease the pathogen may be a virus, bacterium, protozoa, or helminth
- dehydration and malnourishment are concerns
40
dysentery
- may be caused by various pathogens
| - shingella spp
41
hepatitis
- viral hepatitis may be caused by HAV, HBV, HCV, HDV, HEV, HGV, and hepatitis GB virus C
- can result from mono, yellow fever, and cytomegalovirus
- liver necrosis, hepatomegaly, jaundice, and bilirubinemia
42
hepatitis vaccine
- available for HAV and HBV
43
hepatitis A vaccine
- inactivated virus grown in cell culture
| - recommended for people at increased risk
44
hepatitis B vaccine
- subunit vaccine produced by genetically engineered sacchromyces cerevisiae (bakers yeast)
- routinely administered to children and US
- required for HCP exposed to blood
- HBV immunoglobulin can be given to unvaccinated pt who have just been exposed to HBV
45
hepatitis A
- sing stranded RNA
- fecal oral transmission, person to person, infected food handler, focally contaminated food and wate
- abrupt onset
- mild lasting 1-2 wks to severe debilitating last several months
- no chronic infection
- most recover without treatment
46
hepatitis B
- double stranded enveloped DNA virus in hepadnaviridae family
- only DNA virus that causes hep
- sexual or household contact, mother to infant before or after birth, needles, tattooing
- gradual onset, jaundice is typical, may lead to cirrhosis or hepatocellular carcinoma
- unapparent to fulminating fatal cases
- chronic infection occurs
47
hepatitis C
- singel stranded enveloped RNA virus in flaviviridae family
- parenterally transmitted, rarely sexual
- gradual onset
- 50-80% develop chronic infection
- may lead to cirrhosis or hepatocellular carcinoma
- #1 reason for liver transplant
- no vaccine
48
hepatitis D
- single stranded enveloped RNA viral satellite in delta virus genus
- exposure to infected blood/fluids, contaminated needles, sexual,
- confection with HBV is necessary
- abrupt onset, may progress to chronic and severe disease
- HBV vaccine
49
hepatitis E
- single stranded noneveloped RNA virus in calciviridae family
- fecal oral transmission, mainly focally contaminated water, person to person
- similar to A, no chronic form
- children usually asymptomatic
- usually benign and self limiting
- high mortality in pregnant woman, more severe symptoms with age
50
hepatitis G
- single stranded RNA virus in flaviviridae family
- parenteral transmission
- chronicity
- little evidence of liver disease, no symptoms resembling hep viruses
- HGV may slow down progression of HIV to AIDS
51
human immunodeficiency virus infection/acquired immunodeficiency syndrome
- HIV/AIDS
- HIV 1 is more common than HIV 2
- single stranded virus in retrovirus family
- transmission: direct sexual contact, needles/syringes, transfusion of contaminated blood, mother to child through placenta, infected organ transplant, needle/scalpel/broken glass
- #6 cause of death worldwide
52
common HIV modes of transmission
- direct sexual contact
- transfusion of contaminated blood products
- contaminated needles and syringes by IV drug abuse
- placenta, breastfeeding, during delivery
- not through insect bites
53
laboratory diagnostics of HIV
- immunodiagnostic procedures of antigen and antibody detection
- most antibodies detectable within 1-3 month but can be 6+ months
- enzyme linked immunoabsorbant assay (ELISA) test first, then western blot analysis or indirect fluorescent antibody test to confirm
- quantitative assessment of viral RNA load used to monitor effectiveness of antiviral therapy
54
signs and symptoms of HIV
- occur within several weeks to months
- initially acute self-limiting mononucleosis like lasting 1-2 wks
- fever, rash, headache, lymphadenopathy, pharyngitis, myalgia, arthralgia, aseptic meningitis, retro-orbital pain, weight loss, depression, GI distress, night sweats, oral/genital ulcers
- often undiagnosed or misdiagnosed due to long time of developing antibodies
- without HIV treatment 90% develop AIDS
55
AIDS
- life threatening syndrome
- invasion and destruction of helper T cells leading to immunosuppression
- secondary infections caused by viruses, protozoa, bacteria, and fungi become systemic and cause death
- die as a result of overwhelming infections from pathogens and opportunistic pathogens
56
Kaposi sarcoma and AIDS
- Kaposi sarcoma is a cancer
- frequent complication of AIDS
- caused by human herpes virus 8
57
AIDS treatment
- combination of drugs are extending lives
| - without anti HIV treatment almost 100% of AIDS its die
58
mumps
- caused by mumps virus and RNA virus
- transmission via droplet spread and saliva contact
- acute viral infection characterized by fever and swelling and tenderness of salivary glands
- complications are orchitis, oophoritis, meningitis, encephalitis, deafness, pancreatitis, arthritis, nephritis, thyroiditis, and pericarditis
59
mumps virus (MuV)
- targets ported glands
- mild and self limiting complete and uncomplicated recovery
- incidence declining
60
measles virus
- morbillivirus
- causes measles but not German measles
- highly contagious but self limiting
- transmission via respiratory droplets
- contagious during incubation period
- Koplicks spots on tongue and oral epithelium followed by raised res rash that fades to brown, sore throat, cosh, headache, fever
- rash = end of contagiousness
- complications are laryngitis and pneumonia
- treatment is antipyretics, cough suppressants, hydration, and antibiotics as prophylactic
- MMR requires booster
61
infectious mononucleosis
- caused by Epstein Barr
- acute viral disease that may be asymptomatic
- fever, sore throat, lymphadenopathy, splenomegaly, and fatigue
- self limiting 1- several weeks
- rarely fatal
62
epstein barr virus
- causes mononucleosis
- DNA virus in herpesviridae family
- transmission via saliva contact
- oncogenic or associated with lymphomas, carcinomas, and sarcomas
63
viral hemorrhagic diseases
- caused by dengue virus, yellow fever virus, crimean Congo hemorrhagic fever virus, Lassa virus, Ebola virus, and Marburg virus
- ebola and Marburg are very large filamentous viruses
- reservoirs include infected humans and infected African green monkeys (Marburg)
- transmission via direct contact with blood, secretions, internal organ, or semen
64
viral hemorrhagic disease symptoms
- sudden onset of fever, malaise, myalgia, headache, pharyngitis, vomiting, diarrhea, rash, internal hemorrhage
- marbug 25% fatal ebola 50-90% fatal
- all cases tracked back to africa
65
ebola and Marburg viruses
- pleomorphic viruses
- sever hemorrhagic fever, myalgia, rash, vomiting and bloody diarrhea
- no cure or treatment, high mortality, few survive past 3 wks
- monkeys are suspected resevoirs
66
poliomyelitis
- caused by poiliovirus
- minor illness with fever, headache, nausea, and vomiting
- 1% progresses to severe muscle pain, stiffness of neck/back with or without flaccid paralysis
- most common in older children and adults
- vaccine in 1950s
67
polio virus
- in enterovirus group with picornaviridae
- only affects humans
- transmission fecal oral route and throat secretions
- causes poliomyelitis
- most asymptomatic
- paralysis is permanent if neutrons are destroyed
- no cure but recovery confers immunity
- treatment is management of symptoms
68
abortive infection pattern of polio
- excludes CNS
| - presents with mild respiratory infection and minot symptoms
69
vital meningitis pattern of poilio
- non paralytic poliomyelisits
| - damage and destruction of neutrons, headaches, stiffness of neck, and fever
70
rabies
- caused by rabies virus an enveloped RNA virus
- reservoirs are dogs, foxes, coyotes, wolves, jackals, skunks, racoons, mongooses, bats
- transmission through bite of rabid animal, airborne through bats in caves
- usually a fatal, acute viral encephalomyelitis of mammals with mental depression, restlessness, headache, fever, malaise, paralysis, salivation, spasms of throat muscles, convulsions, and death from respiratory failure
- paralysis starts in lowers legs and moves up
- endemic everywhere except Hawaii and Antartica
- person to person transmission is rare
71
lyssavirus
- causative agent of rabies
- transmission by lick, bite, or scratch or inhalation of droplets
- vaccine available
- virus travels along nerves to CNS
- cycle complete when virus occupies salivary glands
- incubation period varies with site and severity of wound
- prodromal period; prickling at wound site, vague symptoms
- acute stage; muscle spams seizures, hydrophobia, coma and death
- recovery rare if untreated
72
viral meningitis
- caused by many different viruses
- common but rarely serious
- acute illness rarely exceeds 10 days
- sudden onset of febrile illness with s&s of meningeal involvement
- mononuclear WBC, increased protein, normal glucose and absence of bacteria in CSF
- rash may develop
- GI and respiratory symptoms may occur when caused by and enterovirus
- most commonly caused by enteroviruses
- other causes: coxsackie, arbovirus, measles/mumps virus, herpes, VZV, lymphocytic cchoriomeningitis, adenovirus, leptospirosis
73
viral encephalitis
- arthropod borne viral encephalitis is an acute inflammatory viral disease
- may be asymptomatic or have mild fever and headache
- severe infection possible with headache, high fever, stupor, disorientation, coma, tremors, convulsions, spastic paralysis, death
- person to person transmission is rare (transfusion, organ transplant, breast milk, transplcentally)
74
arboviruses
- west nile, yellow fever, dengue virus
- vaccine available and recommended for travellers
- dengue hemorrhagic fever and dengue shock syndrome
- mortality 5-40%
75
yellow fever virus (YFV)
- mostly benign or mild
| - extreme manifest with oral and nasal bleeding, jaundice, and kidney damage
76
undue virus
- breakbone fever
| - sever arthralgia and myalgia
77
dengue hemorrhagic fever and dengue shock syndome
- hypotension, bleeding, thrombocytopenia
78
west nile virus
- can infect humans, birds, mosquitos, horses
- human infection from mosquitos, also blood transfusion, organ transplant, transplacental and breast milk
- can cause severe CNS infection (encephalitis, meningitis, meningitoencephalitis)
- west nile fever: fever, headache, fatigue, aches, rash
- asymptomatic or mld in most cases (except encephalitis)
