+ RNA Viruses – Flashcards
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Unlock answers| Examples of enveloped +sense RNA viruses |
Toga flavi corona(helical) |
| Examples of non enveloped +RNA viruses |
Picorna calici astro |
| features to + sense RNA viruses |
Cubical nucleocapsid translation first step cytoplasmic life cycle Non segmented single strand one RNA genome |
| Positive RNA viruses |
| Carry a mRNA type positive RNA gneome |
| Examples of togaviruses |
Rubella alphavirus |
| How are alphaviruses transmitted |
| Mosquitos |
| What does rubella virus infect |
| Humans only |
| Rubella virus |
Positive sense RNA virus single serotype infects humans only |
| how is rubella transmitted and replicated |
| Droplet infections/respiratory replication in respiratory tract viremia |
| German measles |
Acute disease/self limiting disease in adults rubella, 3 days measles, third disease blotchy, non confluent rash-appear on the face and descend to body rashes stay for 3 days cervical lymphadenopathy |
| Congential rubella syndrome |
Teratogenic effect of rubella first trimester infections of the fetus cause severe damage |
| Permanent defects of congential rubella |
Congential heart disease (ductus arteriosis) total or partial blindness: cataract, chorioretinitis, glaucoma neurosensory deafness |
| Transient defects of congential rubella virus |
Thrombocytopenic purpura hepatospleenomegaly meningoencephalitis |
| CNS involvement in congenital rubella virus |
Mental retardation progressive rubella panencephalitis |
| Vaccine for rubella virus |
| Live attenuated virus |
| How do you diagnose rubella virus |
| Elisa for rubella antibodies |
| Alphaviruses |
Mosquito transmitted togavirus mostly subclinical or inapparent infections eastern equine encephalitis(eee) western equine encephalitis (wee) venezuelan equine encephalitis (vee) chikungunya: arthropathy causes viremia enecphalitis of horses, birds and humans |
| Arbovirus infections |
Encephalitis rash fevers hemorrhagic fevers virus introduced in bloodstream viremia produced fever, chills, aching, rapid onset |
| Arboviruses |
Insects (mosquito, sandfly, ticks) toga, flavi, rhabdo, reo and bunya all are RNA viruses cytoplasmic life cycle summer, fall, water stagnation, insect activity abandoned tires, rainfall, mosquito eggs multiply in insects, heavy load in saliva persistent infection in insects, no disease viremia in insects and vertebrate host overwintering in eggs jungle cycle, urban cycle |
| Flaviviruses |
| Single transcription, translation unit |
| St. Louis Encephalitis |
Mosquito-borne flavivirus birds as reservoir east coast, Midwest, endemic in the usa |
| Japanese Enceohaphalitis |
Mosquito borne flavivirus many Asian countries Pigs, birds as reservoirs killed virus vaccine |
| Ticked borne encephalitis |
| Mostly in Europe |
| Yellow fever |
Mosquito Borne flavivirus single serotype live attenuated vaccine (17D) endemic in South America, Africa thousands died in the USA in the past hepatitis, hemorrhage into stomach (black vomitus) |
| Dengue |
four different serotypes/vaccine hard mosquito borne flavivirus acute infection dengue H shock syndrome immune complex involving two different serotypes asain countries, south america(Nicaragua) |
| Hepatitis c |
Flavivirus, not transmitted by insects multiple serotypes most common cause of transfusion-associated non-A, non-B hepatitis by sexual activity, I/V drug use, blood products both acute and chronic infection major cause of hepatocellular carcinoma alpha interferon treatment |
| Coronaviruses |
The only enveloped helical (+) sense virus respiratory and gi infections an important cause of common cause infects animals and humans |
| SARS |
Type of coronavirus severe acute respiratory syndrome flu like symptoms, pneumonia feb 2003, Asia, 12 countries 10,000 infected, 900 died 2004 very few cases |
| Picorna virus |
Smallest group of RNA virus genome:single transcription, translation unit protein linked at 5' end Cap independent translation |
| Three subgroups of picoranaviruses |
Enteroviruses rhinoviruses heparnaviruses |
| examples of enteroviruses |
Polio 1,2,3 coxsackie a and b echoviruses |
| Enteroviruses |
Cubical, non enveloped viruses polyprotein produced from genome resistant to acid pH of stomach oral-fecal route of transmission most infections in children replicate in oropharynx, gut mucosa viremia, spread to CNS
|
| What is the host for polio virus |
| Humans only |
| Polio virus |
1,2,3 serotypes, human only host hematogenous and neuronal spread to CNS anterior horn of brain stem or spinal cord infected |
| Abortive poliomylitis |
| No CNS involvement |
| Aseptic meningitis |
| Stiff neck, meningeal irritation |
| Paralytic poliomyelitis |
| Assymmetric flaccid paralysis sensory perception intact |
| Bulbar polio |
| Paralysis of muscles of the soft palate, pharynx (9;10 cranial nerves severely affected) |
| Coxsackie A |
| Herpangina: sore throat, vesicles on soft palate similar to HSV-1 Acute hemorrhagic conjunctivitis Hand foot mouth disease: vesicular lesions on hand and face |
| Coxsackie B |
Pleurodynia (muscle pain in the chest, epidemic myalgia, Bornholm disease) Aseptic meningitis and mild paresis Neonatal myocarditis, pericarditis, Myocardiopathy, Diabetes Mellitus |
| ECHO virus |
enteric human orphan virus aseptic meningitis |
| rhinovirus |
picorna virus, +stranded RNA, cytoplasmic cycle unstable to acid pH of stomach (enteroviruses are acid stable) more than 100 serotypes known, vaccine development difficult |
| rhinovirus epidemiology and disease |
most frequent cause of common cold school children are considered to transmit this virus most efficiently respiratory route of enter, personal contact |
| hepatitis A structure and biology |
picorna, +sense RNA no envelope, stable to ether, acid, and heat relatively stable to disinfectants only one serogroup |
| hepatitis a epidemology and disease |
infectious hepatitis or short incubation hepatitis no chronic hepatitis or parentaral oral-fecal route (rarely by parentaral) raw seafood probably derived from feces contaminated water |
| hepatitis a vaccine |
| inactivated viral vaccine for foreign travellers |
| caliciviruses/norwalk virus (ohio) |
epidemic gasterenteritis non-enveloped plus RNA waterborne, food borne, (oral-fecal route) and shellfish associated |
| caliciviruses/norovirus |
| gastroenteritis |
| hepatitis E |
+ RNA, no envelope oral-fecal route of transmission raw seafood associated gastroenteritis and hepatitis |
| characteristic of most viruses that infect the gut |
| they dont have an envelope |
| astroviridae |
non-enveloped + RNA virus oral-fecal route of transmission infantile diarrhea |
