L28- Multi-system Infections I Flashcards
Multi-system Infection definition
Involves 3 or more of the following systems:
- mucous membrane
- GI
- hepatic
- muscular
- renal
- hematologic
- CNS
compare and contrast endemic and emerging zoonoses:
- (1) spreading potential
- (2) affected regions
- (3) prevention
(animal to human transmission) Endemic Zoonoses: -limited spreading potential -poorer countries / neglected communities -tools easily available for prevention
Emerging Zoonoses:
- potential for pandemic spread
- low and high-income countries
- limited tools available for prevention
list the common multi-system infections transmitted via mosquito
Yellow fever
Dengue
ChikV
Zika
list the common multi-system infections transmitted via ticks
Rocky mountain spotted fever (rickettsia rickettsii) Lyme disease (borrelia burgdorferi)
Ehrlichiosis (E. chaffeenis, E. Ewingii)
Anaplasmosis (A. phagocytophilium)
list the common multi-system infections transmitted via flies
Leishmaniasis (leishmania spp.)
Trypanosomiasis (trypanosomia spp.)
(1) are the common vector-born diseases transmitted through mosquitoes, specifically the (2) mosquito. (3) is the term used to group all of (1) and indicates (4) property of (3). (1) are spread in (5) methods.
1- YF, dengue, ChikV, zika
2- Aedes aegypti
3- Arboviruses
4- virus is transmitted by certain blood-feeding arthropods
5- human to human (vector, vertical, sex) OR animal to human
The common arboviruses are usually apart of the (1) or (2) viral family. (3) or (4) is the common initial presentation of an infection by (1) or (2). (5) is the subsequent presentation. (6) may be able to inhibit (4) or (5).
1- flaviviruses (YF, dengue, zika)
2- alphaviruses (ChikV- togaviridae)
3- asymptomatic (more common)
4- Primary viremia: mild systemic disease
5- Secondary viremia: severe systemic disease or encephalitis
6- Abs against virus –> prevents viremia
Flaviviruses and alphaviruses usually infect (1) cells. They are good inducers of (2) production as a result, which leads to (3) initially. Presence of (4) can block disease progression, but presence of (5) can enhance infections via Fc receptors.
1- myeloid progenitor cells – monocyte-macrophage lineage
2- IFN and CKs
3- prodromal syndrome
4- neutralizing Abs
5- non-neutralizing Abs
Common vector-borne Flaviviruses are (1). (2) is the main characteristic seen in all of (1). (3), give a brief description of the pathological highlights for each of (1).
1- YF, dengue, zika
2- high fever, ~104F
3:
- dengue: break-bone fever, retro-orbitial pain
- zika: milder disease in comparison, conjunctivitis, 20% symptomatic
- YF: severe disease, degeneration of liver (jaundice), heart, kidney + hemorrhage (massive GI bleeds = black vomit, coffee ground appearance)
(1) is the main Togavirus via vector-borne infections, where (2) is the main clinical presentation.
1- CHIK
2:
- intense / severe, debilitating disease
- viremia clear w/in 7 days
YF:
- (1) incubation time
- (2) duration
- (3) indicate presence of which symptoms: fever, HA, rash, myalgia, joint pain, conjunctivitis
1- 6-7 days
2- 4-5 days
3- fever, myalgia
Dengue:
- (1) incubation time
- (2) duration
- (3) indicate presence of which symptoms: fever, HA, rash, myalgia, joint pain, conjunctivitis
1- 4-10 days
2- 2-7 days
3:
- HA, myalgia, joint pain (always)
- fever, rash (possibly)
Chikungunya:
- (1) incubation time
- (2) duration
- (3) indicate presence of which symptoms: fever, HA, rash, myalgia, joint pain, conjunctivitis
1- 3-7 days
2- ~1wk
3:
- fever, joint pain (always)
- HA, myalgia, rash (possibly)
Zika:
- (1) incubation time
- (2) duration
- (3) indicate presence of which symptoms: fever, HA, rash, myalgia, joint pain, conjunctivitis
1- ~7 days
2- <1wk
3:
- fever, rash, joint pain, *conjunctivitis (always)
- HA, myalgia
Yellow Fever:
- (1) viral family
- (2) genomic makeup and viral structure
- (3) geographic locations
- (4) reservoirs
- (5) vector
1- flavivirus
2- (+)ssRNA, enveloped, icosahedral
3- 90% Africa, some in S. Amer. (no Asia)
4- non-human primates
5- Aedes aegypti (Africa), Haemagogus spp. / Aedes (S. Amer.)
After injection of yellow fever virus, it travels to (1) areas. (2) is the main target organ, where it will infect (3) cells and initiate (4). (5) is the net results of yellow fever pathogenesis. Note, for diagnosis of YF, (6) must be ruled out.
1- *liver, *kidney, spleen, lymph nodes, bone marrow, myocardium
2- liver
3- hepatocytes via Kupffer cells
4- eosinophilic degeneration –> CK release
5- Councilman bodies (see another slide) – apoptotic masses in hepatocyte cytoplasm
6- viral hepatitis
describe Councilman bodies
common after YF infection of liver
- apoptotic masses
- hepatocytic cytoplasm + renal system
Note- in other hemorrhagic fevers (DHF, Marburg, Ebola)
describe the clinical presentation and progression of yellow fever:
- initial phase
- secondary phase
1) incubation, 6-7 days
2) abrupt onset fever, myalgia, prostration (lying on floor) –> resolves in 4-5 days
3) Severe cases –> fever, jaundice, bleeding, kidney issues (hematemesis- black vomit) and collapse
4) possible fatality –> secondary to CK storm, shock, and or multi-organ failure
Dengue Fever:
- (1) viral family
- (2) genetic makeup and viral structure
- (3) serotypes
1- flavivirus
2- (+)ssRNA, enveloped, icosahedral
3- DEN-1, DEN-2, DEN-3, DEN-4
discuss immunity and re-infection of Dengue fever
-lifelong immunity develops for a particular serotype (DEN-1/2/3/4) after exposure and recovery
- partial temporary cross-immunity for other serotypes develops initially
- —>
- infection w/ different serotype => increased severe dengue (worse then previous infection- most likely DHF)
After injection of dengue fever virus, it replicates in (1) and infects (2) areas. (3) is the eventual target organ, where it infects (4) cells and initiates (5).
1- LNs
2- endothelial cells of capillaries, monocytes, macrophages, dendritic cells
3- liver
4- hepatocytes via Kupffer cells
5- eosinophilic degeneration –> CK release
describe the pathogenesis of DHF / DSS
Severe Dengue, DHF, Dengue Shock Syndrome (DSS)
1) repeat dengue infection of different serotype
2) memory T cells activated
3) CK release –> initiates inflammatory response
4) weakening and eventual rupture of vasculature
5) loss of plasma / blood –> shock
In reinfections with Dengue, (1) promotes viral uptake into macrophages and (2) limits the replication of virus.
1- non-neutralizing Abs (sub-neutralizing)
2- IFNs –> local secretion at injection site –> stimulates innate immune response
Dengue Fever clinical features:
- (1) incubation period
- (2) duration of Sxs
- (3) is the main Sx and is accompanied by at least two of the following Sxs: (4)
1- 4-10 days
2- 2-7 days
3- sudden high fever, ~104F
4- severe HA, retro-orbital pain, muscle / joint pains (breakbone fever), n/v, swollen glands, rash (petechiae: white islands in sea of red)
Warning signs for Severe Dengue occur (1) days after initial symptom in conjunction with (2) change. Warning signs at this time include (3). (4) is necessary in the next 24-48hr in order to avoid (5).
1- 3-7 days
2- dec in T –> ~100F
3- severe abdominal pain, persistent vomiting + hematemesis, tachypnea, bleeding gums, fatigue, restlessness
4- proper medical care and support
5- death or critical complications
Chikungunya:
- (1) viral family
- (2) genetic makeup and viral structure
- (3) pre-2013 outbreak affected regions –> (4) post-outbreak regions
1- togavirus (alphavirus)
2- (+)ssRNA, enveloped, icosahedral
3- africa, asia, europe, indian/pacific ocean (NOT N./S. Amer.)
4- global (w/ Americas)
After injection of chikungunya virus, it targets and replicates in (1). After replication, it disseminates and replicates into (2) areas. (3) is then recruited into infected organs and (4) results in those areas.
1- fibroblasts in dermis
2- muscles, joints, skin (+ liver, spleen, meninges (just neonates)
3- inflammatory cells
4- inflamed joints: fingers, wrists, elbows, knees, ankles, toes
Chikungunya:
- (1) are the people at highest risk
- (T/F) recovery leads to lifelong protection
- (T/F) infections can result in death
1- neonates (infected at birth), older adults (>65y/o), Pts with chronic medical conditions
2- ??T, possibly
3- F, not typically
Chikungunya clinical features:
- (1) incubation period
- (2) typical duration
- (3) most common Sxs
- (4) other Sxs
1- 3-7 days
2- ~1wk to recover —- although joint pain may last for months
3- short-lived fever, joint pain
4- HA, myalgia, joint swelling, rash (hard to see on darker skin)
Zika:
- (1) viral family
- (2) genetic makeup and viral structure
- (3) lineages
- (4) typical presentation
1- flavivirus
2- non-segmented (+)ssRNA, enveloped, icosahedral
3- African, Asian
4- asymptomatic
After injection of Zika virus, it targets (1) receptors on (2) cells in order to undergo fusion and replication. As opposed to DENV, (3) process is inhibited.
1- E-glycoproteins + other glycoprotein cellular receptors
2- epidermal keratinocytes, dendritic cells, **developing neurons
3- apoptosis
Zika clinical features:
- (1) incubation period
- (2) duration of Sxs
- (3) common Sxs
- (4) other Sxs
- (5) complications
1- ~7days
2- <1wk
3- fever, rash, joint pain, *conjunctivitis
4- myalgia, HA
5- Guillain Barre syndrome, microencephalopathy
Zika complications:
- (1) is the most known complication of neonates with (2) as the main feature
- (3) is another rare auto-immune condition where (4) are attacked; more common in (5) population
1- microencephalopathy
2- small head at birth
3- GBS- Guillain Barre syndrome
4- peripheral nerves
5- adult males
list the contraindications of YF vaccine
- children <9mos
- pregnant women
- those with egg allergies
- those with altered immune system