Ambler Viruses Flashcards
(42 cards)
RNA virus families that are from blood sucking arthropods
Bunya, Toga, Flavi
PICORNAviridae
Poliovirus- still wild type cases in India and certain African countries. Recommended booster for travel.
- Mild illness
Asymptomatic or mild fever
- Aseptic meningitis
Fever and meningismus with recovery ~1wk - Paralytic
Destroys presynaptic neurons leaving the horn
Mild fever resolves but 5-10 days later, returns followed by meningismus and then some paralysis
Atrophy of affected muscle group from nerve to follow
Coxsackie A/B
Range asymptomatic to febrile
Respiratory symptoms
Rashes
Aseptic meningitis
Coxsackie A
Herpangina – mild self-limiting fever, sore throat and red vesicles on back of throat
HandFootMouth – children with fever, oral vesicles and small red lesions….guess where?
Coxsackie B
Pleurodynia – fever, H/A and pleurisy
Myocarditis/pericarditis – can be severe (enough for heart transplant eval) but usually self limited.
Rhinovirus/Enterovirus*
Along with corona = common cold. Enterovirus has numerous clinical presentations including cns, gi and respiratory.
CALCIviridae
Vomiting and Explosive watery diarrhea breaks out in a nursing home = norovirus(norwalk like virus)/norwalk virus
vomiting primary problem
267 million infections with 200k deaths/yr
90% of all epidemic outbreaks and 50% all US foodborn illness
24-48 hr incubation
REOviridae
Colorado Tick Fever –’coltivirus’
Fever 1-3 days then ok then fever 1-3 days, then fine. Pretty typical ‘viral syndrome’ +/- rash, +/- hepatosplenomegaly with thrombocytopenia
Infects particularly erythrocytes
March to September (worst June)
Rotavirus
VACCINE! – old vaccine caused intussusception
Rotateq- human bovine reassortment vaccine
Rotarix – live attenuated oral vaccine
One of the leading causes of diarrhea worldwide (mainly children)
BUNYAviridae
Hantavirus
Fever with pulmonary edema/vascular leak and ARDS presentation. Aka ‘sin nombre’ virus in SW USA
Breaks the arthropod rule as it is rodent and insectavore resevoirs.
Asia form is hemmorraghic fever with renal failure
Treatment is supportive
TOGAviridae: Rubella
Rubella (German measles)
Causes fever, lymphadenopathy, rash goes face down and out for 3 days. ‘less sick’ than measles.
Probably life long immunity once disease clears
Young women can get arthritis
toRch – risk increases with earlier infection
–> sensorineural deafness when contracted in utero
Togaviridae: Encephalitis
Eastern Equine Encephalitis, Western EE(none recently) and Venezuelan EE.
EEE with longer prodrome 5-10 days where as little as 1 day in others.
Fever with rigors, H/A, some GI issues
Those that go onto CNS (more likely as we age), can have seizures/epilepsy, coma, hyponatremia, mental retardation, behavior changes and paralysis.
FLAVIviridae
Really crazy how different these viruses are.
Comprise over 60 arthropod born viruses with 30+ causing human disease.
examples: yellow fever, japanese encephalitis, west nile virus, tick borne encephalitis
Yellow Fever
Has live attenuated vaccine
Incubation 3-6 days
Sudden fever, chills, severe H/A, back pain, body aches, vomiting and fatigue/weakness
15% develop severe form with jaundice, bleeding and shock with 20-50% mortality
Supportive
Effective Live Vaccine available
Amazonian area
West Nile
WNF: sudden flu like with myalgias, backache, poss retro-orbital pain w/o neuro. Rash in 50% with LN
Neuro: above without really LN. Can be biphasic. 2/3 enceph;1/3 meningitis. Can affect ant horn with paralysis which can be asymmetric and life long cliniclally like polio.
ST. Louis encephalitis
5-15 days post skeeter
Sudden onset with fever, H/A, dizziness and nausea
Resolve over days to weeks but some go onto CNS:
- Stiff neck, confusion, disorientation, dizzy, tremors and unsteady.
- 40% of children and young adults with fever, H/A and aseptic meningitis. 90% elderly with enceph and overall mortality 5-15%
Flaviviridae: Dengue
High fever and Severe H/A Eye pain Joint pain Mild* bleeding LOW wbc
Dengue Hemorrhagic Fever
Lasts 2-7 days.
24-48 hours of leaky capillaries
May lead to circulatory collapse and major fluid extravisation such as pleural effusions and ascites.
Supportive care quickly can save patient.
FLAVI-viridae: Japanese Encephalitis
Symptomatic in less than 1% but fatal in 25% of those with clinical disease
bad encephalitis symptoms
can present with cord “polio”
can regain neuro function over weeks to years
vaccine (ixiaro) available
Flaviviridae: Tick Borne Encephalitis
Symptoms in 1/250 pts Eastern more severe Biphasic If fever 1st then all good No fever, a second phase with CNS and cord presentation can occur inc meningoencephalitis, polio-like illness, Guillain Barre like illness. Fatal 1%
Zika
not new. 1st human case in 1952
no or mild symptoms to mild dengue.
Male sexual transmission
Pregnant women at risk for transmission to developing fetus.
latest info is all trimesters are at risk
brain pathology – microcephaly and possibly develops after birth
Aedes mosquito
CORONA-viridae
1st big outbreak SARS in 2003
Now MERS (middle eastern resp syndrome)
Only 2 in US (Indiana and Florida), both from Saudi Arabia working in Healthcare and both in May 2014.
Fatality of 35% (CDC) with mortality reported as high as 58%
“Flu-like”
Leuko(lympho)penia*
ORTHO/(PARA)MYXO-viridae
Influenza
Amantadine not used much anymore
Now oseltamivir (tamiflu ®) and zanamivir (relenza®) are mainstay of treatment. Used within 48 hrs of symptoms or else really not helpful.
Peramivir (rapivab®) IV medication
Human Metapneumovirus - paramyxoviridae
Mild URI to severe respiratory on vent
Fever more common than RSV and so is febrile sz
RHABDO-viridae
Rabies – 55k deaths each year but there have been a handful of ‘survivors’. Still nearly 100% fatal.
Vaccine : 4 shots if immunocompetent, 5 if not
Days 0, 3, 7, 14 (28)
IVIG at site if possible and systemically
Day 0 but up to 7 days post exposure with infiltrate as much as possible near wound.
Post Rabies Exposure
Vaccine IM days 0, 3, 7, 14 (28 if immunocompromised)
clean wound with povidine-iodine or soap if not available
HRIG (human rabies Immunoglobulin)
20 IU/kg with as much around the wound as possible otherwise IM near wound.
ARENA-viridae
Lymphocytic ChorioMeningitis virus (LCM)
Typical viral syndrome with leukopenia and thrombocytopenia, then brief improvement then aseptic meningitis and sometimes encephalitis with leukocytosis. *can have low glu in csf!
House mice (urine) associated
Seroprevalence appox 5%
Vertical transmission can occur in utero with inc spontaneous abortions in 1st trimester and later infection with malformations such as intracranial calcifications, hydrocephalus, micro/macrocephaly, mental retardation and seizures. Mortality 30% infants and those that survive, 2/3rds have neuro sequelae
RETRO-viridae: HTLV
Human T Lymphotropic Virus
HTLV-1
Associated with T cell leukemia/lymphoma (ATL)
Also HTLV-1-associated myelopathy (aka tropical spastic paraparesis)
One of the concerning infections for vertical transmission with breast milk
HTLV-2
Not as human tropic
Some ATL and neuro cases.
Human Immunodeficiency Virus
estimated to have entered human population ~1902-1932 based on preserved specimens AIDS first described in 1981 HIV 1983 First test 1985 AZT around 1986 Effective treatment 1996
CD4 T Cell is the general of the immune system army, hit by the HIV. Over time, you lose the war. CD4 count less than 200 = AIDS.
Window phase: test negative still but highly contageous. 0-4 weeks.
