RNA Viruses

RNA Viruses

1. Positive Sense ss

   • quick note - arboviruses use ticks, mosquitoes, and flies to infect - include toga, flavi, and bunyaviridae 
   • Picornavirus
     • Enterovirus
       • mcc of aseptic meningitis especially in kids remember fungal meningitis mcc is cryptococcal
       • Rhinovirus
         • most common cause of hospitalizations in children. second mcc of bronchiolitis vaccine not feasible common cold.
       • Coxsackie
         • cav - herpangina (EV7) - always on posterior end of mouth (herpes leaves lesions on anterior mouth); exanthem and enanthem stuff CA16 - hand foot mouth (ev71) cbv - myocarditis and pericarditis
       • Poliovirus
         • 1 2 3  2 is pretty much gone. ev71 also cause polio. fecal oral. vaccines - opv ipv (we use ipv-inactivated) opv can cause disease (live)
       • Echovirus
     • Hepatovirus
       • hep a vaccine preventable.  not that bad.
     • Parechovirus
     • Kobuvirus
       • aiichi - diarrhea
   • Coronavirus
     • sars mucosally restricted new outbreak in saudi arabia 5/2013 mainly causes respiratory ilness; can cause GI issues in infants. no vaccine.
   • Flaviviridae
     • ixodes ticks - encephalitis these all cause encephalitis and hemorrhagic or normal fever.
     • Japanese Encephalitis Virus Group
       • JEV - vaccine preventable St. louis encephalitis West nile virus
     • Yellow Fever Virus
       • vaccine preventable. can be pretty darn serious. black vomitus
     • Dengue Fever
       • 4 serotypes. lifelong immunity if you get it. SOME cross reactivity.  no vaccine. 4 types of fever and rash: undifferentiated, classical hemorrhagic dengue shock
     • Hepacivirus - Hep c
   • Astrovirus
     • diarrhea. adenovirus 41 40 also cause diarrhea
   • Calicivirus
     • smaller than rotavirus in size.
     • Norovirus
       • fluids and electrolytes. less severe than rota in children watery diarrhea.just wash your hands.cruise ship virus
   • Togaviridae
     • Alphaviridae
       • old world - chikungunya new world - WEEV, EEEV, VEEV no treatment. just supportive. essentially - chikungunya = rash
     • Rubivirus
       • rubella - mmr live vaccine. cataracts cardiac problems not an arbovirus - spread person to person congenital - dangerous during 1 tm of pregnancy only.

2. Negative sense ss

   • Orthomyxoviridae
     • segmented boar
     • Influenza A B C
       • Na inhibitors - oseltamivir, zanamivir (>7 years old; inhaled, works better than oseltamivir) M2 ion channel inh (type A only) -  amantidine, rimantidine; current strains aren't susceptible. all HA's transmitted through water fowl parabasic region - makes virus "high path"
   • Paromyxoviridae
     • Mucosally restricted
       • Parainfluenza
         • croup steeple sign. NOT epiglottitis (HITB) odd years have outbreaks use steroids to prevent closing of trachea
       • hMPV
       • RSV
         • number one cause of bronchiolitis try ribavirin but really use synagis (mAB) need 10x more antibody for nose infection than lung infection.
     • Systemic
       • Morbillivirus - measles
         • koplik's spots rash everywhere very infectious - can be lethal mmr - vaccine.
       • rubulavirus - mumps
         • parotitis (can be any gland really) isolate individual.  mmr - live vaccine.
   • Rhabdoviridae
     • Rabies - vaccine 3 times before exposure. causes unstoppable encephalitis. bullet shaped virus. negri bodies. in texas - skunks and bats. 
   • Filoviridae
     • fruit bats hemorrhagic fever
     • Marburgvirus
     • Ebolavirus
   • Bunyaviridae
     • segmented boar
     • Bunyavirus
       • California encephalitis lacross
     • Hantavirus
       • HFRS - hantaan and seoul use ribavirin HPS - sin nombre virus. deer mouse and cotton rat. variants named by location. progresses quickly.
     • Phlebovirus
       • sandfly. rift valley fever
     • Nairovirus
       • tick borne crimean congo hemorrhagic fever use ribavirin for cchf
   • Deltavirus
     • hep d?

3. Ambisense

   • Arenaviridae
     • segmented boar
     • LCM
       • aseptic meningitis
     • Lassa Fever
       • hemorrhagic nausea, vomiting, diarrhea use ribavirin

4. double stranded

   • Reoviridae
     • segmented boar
     • rotavirus
       • watery diarrhea. 2 live vaccines; intussusception risk number 1 cause of diarrhea in developing countries. destroy the villi after 12 hours as seen on biopsy.
     • coltivirus
       • colorado tick fever
     • reovirus
     • orbivirus