viruses

Virus Family Genus Nucleic Acid Capsid Envelope Serotypes Polio Picornaviridae Enteravirus (PENCH) Echovirus Picornaviridae Enteravirus (PENCH) New Enteravirus Picornaviridae Enteravirus (PENCH) Icosahedral (REO speedwagon Calls RNA, single strand, + (Pierre To Pink Retro Can Covertly Return To Florida) Flamers) Icosahedral (REO speedwagon Calls RNA, single strand, + (Pierre To Pink Retro Can Covertly Return To Florida) Flamers) Icosahedral (REO speedwagon Calls RNA, single strand, + (Pierre To Pink Retro Can Covertly Return To Florida) Flamers) no, (Can Picture REO) A, B, C no, (Can Picture REO) 32 no, (Can Picture REO) 4 Coxsackie Picornaviridae Enteravirus (PENCH) Icosahedral (REO speedwagon Calls RNA, single strand, + (Pierre To Pink Retro no, (Can Can Covertly Return To Florida) Flamers) Picture REO) A - 22, B - 6 Icosahedral (REO speedwagon Calls RNA, single strand, + (Pierre To Pink Retro no, (Can Can Covertly Return To Florida) Flamers) Picture REO) only 1 Icosahedral (REO speedwagon Calls RNA, single strand, + (Pierre To Pink Retro no, (Can Can Covertly Return To Florida) Flamers), 60 Picture REO) ~115 Hepatitis A Picornaviridae Enteravirus (PENCH) Rhinovirus Picornaviridae Rhinovirus Norwalk virus Caliciviridae Calcivirus Hepatitis E Caliciviridae Icosahedral (REO speedwagon Calls RNA, single strand, + (Pierre To Pink Retro Can Covertly Return To Florida) Flamers), 32 Icosahedral (REO speedwagon Calls RNA, single strand, + (Pierre To Pink Retro Can Covertly Return To Florida) Flamers) no, (Can Picture REO) no, (Can Picture REO) Coronavirus Coronaviridae Coronavirus RNA, single strand, + (Pierre Helical, petal Can Covertly Return To Florida) shaped spikes yes Rubella WEE (Western Equine Encephalitis) EEE (Eastern Equine Encephalitis) Icosahedral (REO speedwagon Calls RNA, single strand, + (Pierre To Pink Retro Can Covertly Return To Florida) Flamers) Icosahedral (REO speedwagon Calls Togaviridae (an To Pink Retro Arbovirus) RNA, single strand, + (Pierre Flamers), 1 ARthropod BOrne Alphavirus (RAT) Can Covertly Return To Florida) Capside protein Icosahedral (REO speedwagon Calls Togaviridae (an To Pink Retro Arbovirus) RNA, single strand, + (Pierre Flamers), 1 ARthropod BOrne Alphavirus (RAT) Can Covertly Return To Florida) Capside protein Togaviridae (an Arbovirus) ARthropod BOrne Rubivirus (RAT) yes yes, 3 envelope glycoproteins E1, E2, E3 yes, 3 envelope glycoproteins E1, E2, E3 Icosahedral (REO speedwagon Calls VEE (Venezualan Togaviridae (an To Pink Retro Equine Arbovirus) RNA, single strand, + (Pierre Flamers), 1 Encephalitis) ARthropod BOrne Alphavirus (RAT) Can Covertly Return To Florida) Capside protein Flavivirae (an Arbovirus) ARthropod BOrne Flavivirus Flavivirae (an Arbovirus) ARthropod BOrne Flavivirus Flavivirae (an Arbovirus) ARthropod BOrne Flavivirus yes, 3 envelope glycoproteins E1, E2, E3 St. Louis Encephalitis RNA, single strand, + (Pierre Can Covertly Return To Florida) Icosahedral yes Hepatitis C RNA, single strand, + (Pierre Can Covertly Return To Florida) Icosahedral yes 9 Yellow Fever RNA, single strand, + (Pierre Can Covertly Return To Florida) Icosahedral yes Dengue (Breakbone fever) Flavivirae (an Arbovirus) ARthropod BOrne Flavivirus Flavivirae (an Arbovirus) ARthropod BOrne Flavivirus Bunyaviridae (an Bunyavirus Arbovirus) (Bunyons Present ARthropod BOrne as Hard Nodules) Bunyaviridae (an Phlebovirus Arbovirus) (Bunyons Present ARthropod BOrne as Hard Nodules) RNA, single strand, + (Pierre Can Covertly Return To Florida) Icosahedral yes 4 Japanese B encephalitis Bunyavirus Phlebovirus RNA, single strand, + (Pierre Can Covertly Return To Florida) Icosahedral RNA, single strand, -. RNA bound to N-protein (noncovalent). RDRP. 3 segments (BARRO) Helical RNA, single strand, -. RNA bound to N-protein (noncovalent). RDRP. 3 segments (BARRO) Helical yes yes yes Hantavirus Nairovirus RNA, single strand, -. RNA Bunyaviridae (an Hantavirus bound to N-protein (nonArbovirus) (Bunyons Present covalent). RDRP. 3 segments ARthropod BOrne as Hard Nodules) (BARRO) Helical RNA, single strand, -. RNA Bunyaviridae (an Nairovirus bound to N-protein (nonArbovirus) (Bunyons Present covalent). RDRP. 3 segments ARthropod BOrne as Hard Nodules) (BARRO) Helical yes yes Influenza Orthomyxoviridae Influenza virus RNA, single strand, -. RNA bound to N-protein (noncovalent). RDRP. (8 segments). 2 surface glycoproteins, Hemagglutinin (HA) and neuraminidase (NA) Helical - actually spherical or pleomorphic yes Type A - major pandemic and epidemic strains Type B - milder disease, some epidemics Type C - little disease. Serotype determined by Nprotein. Parainfluenza virus Paramyxoviridae Paramyxovirus RNA, single strand, -. RNA bound to N-protein (noncovalent). RDRP. 2 surface glycoproteins, Hemagglutininneuraminidase (HN), and fusion protein (F). Helical yes 4 serotypes: 1-3 cause disease. Type 3 has infected 95% of kids by age 6. Mumps Paramyxoviridae Paramyxovirus RNA, single strand, -. RNA bound to N-protein (noncovalent). RDRP. 2 surface glycoproteins, HemagglutininNeuraminidase (HN) and fusion protein (F). Helical yes only 1 Measles Paramyxoviridae Morbillivirus RNA, single strand, -. RNA bound to N-protein (noncovalent). RDRP. 2 surface glycoproteins, Hemagglutinin (HA) and fusion protein (F). Helical yes only 1 RSV (Respiratory Syncytial Virus) Paramyxoviridae Pneumovirus RNA, single strand, -. RNA bound to N-protein (noncovalent). RDRP. 1 surface glycoprotein - fusion protein G. Helical yes Rabies VSV (Vesicular Stomatitis Virus) Rhabdoviridae Lyssavirus Rhabdoviridae Vesiculovirus RNA, single strand, -. RNA bound to N-protein (noncovalent). RDRP. RNA, single strand, -. RNA bound to N-protein (noncovalent). RDRP. Helical - bullet shaped Helical - bullet shaped yes yes Marburg Filoviridae Filoviridae Ebola Filoviridae Filoviridae RNA, single strand, -. RNA bound to N-protein (noncovalent). RDRP. RNA, single strand, -. RNA bound to N-protein (noncovalent). RDRP. ssRNA, +, coated with Nucleocapsid protein (NC), 2 identical segments. Reverse transcriptase (RNA dependent DNA polymerase) and Integrase (IN) contained in capsid. ssRNA, +, coated with Nucleocapsid protein (NC), 2 identical segments. Reverse transcriptase (RNA dependent DNA polymerase) and Integrase (IN) contained in capsid. ssRNA, +, coated with Nucleocapsid protein (NC), 2 identical segments. Reverse transcriptase (RNA dependent DNA polymerase) and Integrase (IN) contained in capsid. 3 replication genes: (1) GAG (Group Ag) - makes CA, NC, MA, PR (2) POL (polymerase) - makes RT and IN (3) ENV - makes SU, TM. dsRNA, 11 segments, carries RNA polymerase for dsRNA replication Helical yes HTLV - I, II Retroviridae Oncovirus Foamy viruses Retroviridae Spumavirus Helical Icosahedral (REO speedwagon Calls To Pink Retro Flamers). Protease contained between capsid and envelope Icosahedral (REO speedwagon Calls To Pink Retro Flamers). Protease contained between capsid and envelope yes yes, SU (gp120), TM (gp41), and matrix protein associated with envelope. yes, SU (gp120), TM (gp41), and matrix protein associated with envelope. HIV Retroviridae Lentivirus Reovirus Reoviridae Reovirus Icosahedral (REO speedwagon Calls To Pink Retro Flamers). Protease contained between capsid and envelope Icosahedral core with 2 capsid shells yes, SU (gp120), TM (gp41), and matrix protein associated with envelope. no (Can Picture Reo naked) Rotavirus Reoviridae Rotavirus Orbivirus Reoviridae Orbivirus dsRNA, 11 segments, carries RNA polymerase for dsRNA replication dsRNA, 11 segments, carries RNA polymerase for dsRNA replication Icosahedral core with 2 capsid shells Icosahedral core with 2 capsid shells no (Can Picture Reo - 3 subgroups, 9 naked) serotypes no (Can Picture Reo naked) Adenovirus Adenoviridae DNA, double strand, linear, bound to histone-like proteins Icosahedral, with 12 penton spikes no 47, divided into 6 groups HHV-1 (HSV-1) Herpesviridae alpha Simplexvirus DNA, double strand, linear, nuclear replication Icosahedral yes HHV-2 (HSV-2) Herpesviridae alpha Simplexvirus DNA, double strand, linear, nuclear replication Icosahedral yes HHV-3 (VZV) Herpesviridae alpha Varicellovirus DNA, double strand, linear, nuclear replication Icosahedral yes HHV-4 (EBV) Herpesviridae gamma Lymphocryptoviru DNA, double strand, linear, s nuclear replication Icosahedral yes HHV-5 (CMV) HHV-6 HHV-7 Herpesviridae beta Herpesviridae beta Herpesviridae beta DNA, double strand, linear, Cytomegalovirus nuclear replication DNA, double strand, linear, Roseolovirus nuclear replication DNA, double strand, linear, Roseolovirus nuclear replication Icosahedral Icosahedral Icosahedral yes yes yes HHV-8 (KSHV) Herpesviridae gamma Rhadinovirus DNA, double strand, linear, nuclear replication Icosahedral yes Herpes Simiae yes assembled by "Wrapping" yes assembled by "Wrapping" Smallpox Poxviridae Orthopoxvirus DNA, double strand, linear, cytoplasmic replication Complex Molluscum Contagiosum Poxviridae Orthopoxvirus DNA, double strand, linear, cytoplasmic replication Complex Papillomavirus Papovaviridae Papillomavirus DNA, double strand, closed circular, has histones. Makes 8 early proteins and 2 capsid (late) proteins Icosahedral no, (Naked woman getting a PAPsmear). 42 strains JC Polyomavirus Papovaviridae Polyomavirus DNA, double strand, closed circular, has histones. Makes 3 T antigens, and 3 capsid proteins (VP1, VP2, VP3) Icosahedral DNA, double strand, closed circular, has histones. Makes 3 T antigens, and 3 capsid proteins (VP1, VP2, VP3) Icosahedral no, (Naked woman getting a PAPsmear). no, (Naked woman getting a PAPsmear). BK Polyomavirus Papovaviridae Polyomavirus Parvovirus B19 Parvoviridae Parvovirus DNA, single strand (PAR 1), linear Defective parvoviruses, require Adenovirus to replicate. Icosahedral no, (Naked woman getting a PAPsmear). AAV - AdenoAssociated Virus Parvoviridae Hepatitis B Hepatitis D Hepadnaviridae Hepadnavirus DNA, partially double stranded, part single stranded, nuclear replication. (1st complete dsDNA - via DNA-dependent DNA polymerase. Then transcribe RNA, and encapsidate RNA in cytoplasm. RNA in new capsid uses reverse transcriptase to make new DNA - partial double strand.) Icosahedral ssRNA yes Kuru Prion Creutzfeldt-Jakob disease Prion Scrapie BSE - Bovine Spongiform Encephalopathy Prion Prion TORCHES Six Diseases of Childhood Method of self-defense of cells. When PKR activated, it inactivates eIF2-alpha, which halts protein synthesis. see PKR Method of communication for cell defense against viral attack. When cell is infected, it releases IFN, which activates neighbor cell's 2-5(A). 2-5(A) activates RNaseL, which degrades cell's mRNA, and thus shuts down protein synthesis. PKR eIF2-alpha 2-5(A) Killed vaccines "Inactivated" Live attenuated vaccine Subunit vaccine Virus vector vaccine Disease Host Adsorption Route of Infection Resides in? Incubation Time polio - 3 courses: (1) mild febrile illness (2) Aseptic meningitis (3) paralytic poliomyelitis - destruction of motor neurons Human (1) Asymptomatic or mild febrile illness (2) Respiratory symptoms "cold" (3) Rashes (4) Aseptic meningitis (1) Asymptomatic or mild febrile illness (2) Respiratory symptoms "cold" (3) Rashes (4) Aseptic meningitis Type A - herpangina. Type B myocarditis, pericarditis. Both: (1) Asymptomatic or mild febrile illness (2) Respiratory symptoms "cold" (3) Rashes (4) Aseptic meningitis. More common in summer. Hepatitis - fever, malaise, jaundice, lasts 10-21 days, more common in summer. May cause asymptomatic infection in kids. Non-infectious after onset of jaundice. PVR (polio virus receptor) Fecal/Oral GI - Oropharyngeal and intestinal mucosa, viremia, spreads to CNS Humans, mice, etc. Fecal/Oral GI tract Humans, primates Common Cold - afebrile, 85% of adult common colds. Humans ICAM-1 Fecal/Oral Aerosol, fomites, hand to hand spread of mucus membrane secretions GI tract, liver hepatocytes nasopharynx, upper RT. Can grow at 33C, but not at 37C, thus no viremia! Epidemic outbreaks of diarrhea, vomiting, abdominal pain, fever, malaise, myalgia. Often follows common meal. Common in young children and infants. Named for outbreak at Norwalk Elementary school in Ohio. 1-2 days, symptoms last 4-7 days similar to Hep A Common Cold - afebrile, 15% of adult common colds. (1) German measles (3 day measles) fever, lymphadenopathy, red maculopapular rash like measles (cephalo-distal), but only lasts 3 days. (2) CRS - Congenital Rubella Syndrome - (TORCHES - transplacental) - causes heart defects, blindness, enlarged liver and spleen, mental retardation. Caused by maternal viremia, which may be asymptomatic. Fecal/Oral Aerosol, fomites, hand to hand spread of mucus membrane secretions Respiratory Primary growth in nonneural tissue. Viremia. Later spreads to all parts of CNS. Primary growth in nonneural tissue. Viremia. Later spreads to all parts of CNS. 2-3 week incubation, 3 day rash Encephalopathy - Headache, fever, chills, confusion, drowsiness, coma Bird-mosquitobird cycle Mosquito bite 4-21 day incubation Encephalopathy - Headache, fever, chills, confusion, drowsiness, coma Bird-mosquitobird cycle Mosquito bite 4-21 day incubation Encephalopathy - Headache, fever, chills, confusion, drowsiness, coma Bird-mosquitobird cycle Mosquito bite Primary growth in nonneural tissue. Viremia. Later spreads to all parts of CNS. 4-21 day incubation Major Flavivirus in USA, epidemics in fall Mosquito bite Bloodborne, sexual contact, NOT insects! Liver cirrhosis and HCC 10-20 years after infection. Yellow Fever - acute fever, jaundice, hemorrhage, proteinuria. 15% mortality. Discovered during Panama Canal construction. (1) Breakbone fever - Fever, Joint, muscle, back pain for 5-6 days. (2) DHF - Dengue Hemorrhagic fever prior infection with different serotypes. 10% mortality. Monkeys Mosquito bite Hepatocytes 10-20 years Initial growth in regional lymph nodes, viremia and spread to many organs Bird-mosquitobird cycle Mosquito bite Antibodies potentiate uptake? Endemic in SE Asia. Laryngitis, croup, tracheobronchitis, pneumonia. Influenza - IL-1, IFN-alpha, IFN-beta from macrophage causes fever, chills, myalgia, headache, arthralgia. Risk of secondary infections - pneumonia, bacterial infections (staph, etc.). There are 5HA and 2NA transmissible in humans, of total 14HA and 9NA found in animals. Antigenic drift - mutation in HA, NA which allows survival. Antigenic shift - combining of 2 different strains (dual concurrent infection) leads to brand new virus, pandemic! Respiratory disease in people of all ages. Croup in young children. 95% of kids by age 6 have had it, 50% in first year of life. First infection more severe than subsequent. IgE response may contribute to disease. Also laryngitis/croup, tracheobronchitis, bronchiolitis, pneumonia. Type A humans, fowl, swine, horses Type B, C - only humans NA cleaves neuraminic acid, a major component of mucin (respiratory epithelial protective layer). HA binds to sialic acid residues. Respiratory (via fomites). Endocytosis and acidification via M2 ion channels. NA used to cut loose HA to prevent reinfection of same cell when progeny Virus grows in Upper released. RT, no viremia. Incubation period is 1-4 days. Symptoms for 2-3 days. Airborne, Aerosol droplets Upper RT, no viremia. Mumps - salivary glands become inflamed (parotitis), with possible involvement of testes, meninges, pancreas, ovaries. Complications include orchitis, aseptic meningitis Humans only Airborne, aerosol droplets Upper RT and lymph nodes, primary viremia, spread to salivary glands, testes, pancreas, meninges, Incubation period ovaries. 18 days. Measles - (1) prodrome: High fever, conjunctivitis, eyelid inflammation, photophobia, rhinitis, hacking cough, malaise. (2) Koplik's spots - red based lesions with blue/white centers in oropharynx. (2 days before rash). (3) Rash - Muculopapular (small, red, flat or raised), spreads from head down, drips off in 6 days. Complications: otitis media, croup, bronchiectasis, encephalitis, Guillian-Barre', SSPE (Subacute Sclerosing Panencephalitis) Humans only Airborne Lower RT infection in infants, young children. Colds in adults. Bronchiolitis, pneumonia. Progression of symptoms is very rapid. Zoonosis reservoir in bats. Maintained in foxes, rats, raccoons. Infects dog, cat. All vertebrates are susceptible Airborne ACh receptor. Glycoprotein spikes on surface of virion (G-protein trimer) aid in virus attachment and Animal bite, entry. spreads to CNS Initial growth in Upper RT, then viremia spreads virus to spleen, Incubation 9-11 kidneys, finally to skin. days Incubation 4-5 days, Virus shed for 1-3 weeks which is why it is the #1 cause of RT infections in Lower RT, no viremia. kids! Rabies - fatal CNS infection. CNS - nerve cells, produces negri bodies 1-2 months Hemorrhagic fever - organs liquefy, death Hemorrhagic fever - organs liquefy, death Monkeys Monkeys (1) Adult T-cell leukemia. (2) Tropical Spastic Paraparesis (aka HAM - HTLV1 associated myelopathy). Presents as ascending weakness in legs. Blood, sexual contact, breast milk Tropism of virus for T cells. (1) Acute HIV syndrome - (mono-like) fever, malaise, lymphadenopathy, pharyngitis, about 1 month after exposure, lasts for 8-12 weeks (2) Latency for 8 years. (3) AIDS - Fever, weight loss, night sweats, adenopathy, bacterial and skin infections - Candida esophagitis, PCP, MAI, Kaposi's sarcoma, encephalopathy Human, Monkey CD4 receptors + cytokine receptor CCR5 at early stage, CXCR4 at late stage Blood, sexual contact, transplacenta (TORCHES) Infects CD4+ lymphocytes, resides in macrophages and lymph nodes Latent for 1-2 months before ELISA or Western Blot is positive no human disease Acute gastroenteritis and severe diarrhea in children - leading cause of diarrheal death. Ubiquitous - 90% of kids by age 3 have antibodies. Most prevalent in winter months. Villi of small intestine (epithelial cells) no human disease Respiratory, conjunctivitis, GI, and urinary infections. Adenovirus can block host PKR and apoptosis defenses. It also causes tumors in hamsters. (1) Gingivostomatitis (Fever blisters) lips. (2) Keratoconjunctivitis (aka herpetic keratitis) - eyes, can lead to blindness. Lesions usually last 8-10 days and heal w/ no scarring. (3) Human Encephalitis - fever, focal neuro deficits. beginning 6-18 Treatable! months of age Capsid protein spikes involved in Fecal/Oral, binding Respiratory Heparan Sulfate, HveA Direct contact w/ infected person Trigeminal ganglia Latent w/ lifelong recurrences Genital herpes, neonatal herpes. Human Heparan Sulfate, HveA Sexual contact Sacral ganglia Latent w/ lifelong recurrences Varicella (chickenpox) - children 2-6 years old. Zoster (shingles) - 10-20% of adults. Unilateral dermatomal distribution - Very painful lesions, usually in patients over 60. Someone with shingles CAN spread VZV to kids and cause chicken pox, but cannot infect themself with chicken pox! After we have chicken pox, VZV lies dormant in dorsal root ganglia and re-activates to cause shingles, but never chicken pox. Human Infectious mononucleosis - polyclonal activation of B cells, abnormal cytotoxic T cells produced to kill infected B cells. Also causes Burkitt's lymphoma, Nasopharyngeal carcinoma, Oral hairy leukoplakia, Hodgkin's Lymphoma (1) Cytomegalic inclusion disease (Salivary gland disease) - mostly in infants. (2) Severe disease w/ immunocompromised - CMV retinitis, CMV colitis, lymphoma (3) Mononucleosis-like disease in adolescents and adults - heterophil negative. (4) In neonates, can cause MR or deafness (in 10% of babies w/ CMV), and mortality. (5) May cause restenosis following angioplasty, may promote growth of vascular endothelium. (6) CMV pneumonitis in transplant (BM) patients Rash in infants (roseola, exanthum subitum, "sixth disease"). Phosphatidyl serine receptors Respiratory mucosa, then spreads to liver, spleen, skin. Pox rash Respiratory route - is due to infection of aerosolized vascular endothelial particles - VERY cells. VZV remains in contagious from dorsal root ganglion to infected child cause shingles. Human CR2 receptor Virus is ubiquitous, salivary transmission called "kissing disease" Epithelial cells of pharynx. Spreads to lymph nodes, salivary glands. Latent period of 1021 days, infection lasts 2-3 weeks Infectious mononucleosis 30-50 day incubation period, 2-4 week illness. Pan-B cell activation Humans - other strains found in mice, monkeys Ubiquitous Person-person spread, downregulation of Most human cells and MHC molecules organs, slow growth via 2-5A compared to HSV-1 Blood mononuclear Oral secretions cells Lies dormant in macrophages. Kaposi's sarcoma Resembles HSV-1, causes encephalomyelitis, 75% fatal. Hazard for monkey handlers. Sexual contact Lymphoid cells Smallpox - rash for 2-4 weeks, 25% mortality rate Small, pink or white, wart like papules with central dimple appear on face, arms, back. Lesions persist for up to 2 years. Respiratory URT, regional lymph nodes, viremia, skin 1-12 day latency, then rash for 2-4 weeks Direct contact spread. Epithelial cells of skin and mucus membranes. Virus transforms stratum basale cells (via p53, Rb) to cause rapid proliferation. (1) Warts - hands, feet, genitalia, etc. Human strain, (2) Increased cervical cancer risk in deer strain, women bovine strain, etc. PML - Progressive Multifocal Leukoencephalopathy. Shopper at JCPenny's stumbling, saying "Where are the P-P-Pants?" Amnesia, dysarthria, Ataxia. 70-80% of people may have antibodies to JC polyoma, but symptom much more common in immunosuppressed. Ubiquitous like Burger King - mild or asymptomatic respiratory infection in kids. 70-80% of people may have antibodies, but symptoms more common in immunosuppressed. Direct contact spread. Latent and may resurface w/ stressors. DNA is episomal in infected cells. (1) Fifth disease - Slapped cheek syndrome in kids - due to immune complex deposition. (2) Aplastic anemia in prior anemia patients. (3) Polyarthritis - immune complex deposition in joints. (4) Fetal hydropsis - fetal loss in 10% of maternal infections. No congenital abnormalities if fetus survives. P-antigen on erythoid cells Respiratory Erythoid cells (immature RBC) in bone marrow (Adults), and liver 4-14 day latent (children). Viremia period Three courses: (1) Acute hep B, with complete resolution (90%). (2) Chronic Hep B. (3) Fulminant Hep B with transplant being only recourse. Acute Hepatitis B - malaise, fever, jaundice, lasting for 2-3months. Chronic - lifelong infection with episodes of active Hep B.Increased risk for HCC if chronic infection. Incomplete (defective) virus. Requires HBV capsid for growth. Spongiform encephalopathy - caused by accumulation of prions (infectious proteins) in brain. Neurological symptoms Spongiform encephalopathy - caused by accumulation of prions (infectious proteins) in brain. Neurological symptoms Bloodborne, sexual contact Hepatocytes 6weeks - 6months before any serology/symptom s appear Human Direct inoculation, ingestion of affected tissue, transplant. Direct inoculation, ingestion of affected tissue, transplant. Long incubation period - months to years Human Long incubation period - months to years Spongiform encephalopathy - caused by accumulation of prions (infectious proteins) in brain. Neurological symptoms Spongiform encephalopathy - caused by accumulation of prions (infectious proteins) in brain. Neurological symptoms - MAD COW disease. The pathogens that can cross the bloodplacenta barrier: Toxoplasmosis, Rubella, CMV, Herpes, HIV, Syphilis Measles, Mumps, Rubella, VZV, parvovirus B19, HHV Sheep, goats, mice Cattle Usually inactivated w/ formaldehyde. Effective on ssRNA viruses, not so effective for dsDNA viruses. Affects free AA groups, thus decreases virus infectivity. Shorter immunity than live attenuated virus, no CMI response (humoral IgG only), higher cost. Produced by growing virus in animal to create mutations. Live attenuated vaccine virus replicates in human, but does not cause disease. Good CMI response (CMI), IgG and IgA humoral response if oral vaccine, rare reversion to virulence, low cost. Purified protein antigen (HBV) Vaccinia - clone gene for immunogen into vaccinia virus, then vaccinate with recombinant vaccinia virus. Vaccine? Salk - killed virus. IM injection, produces IgG Ab, humoral response only. Sabin - attenuated live virus, oral administration, produces cellular and humoral immunity, IgG, IgA - natural route of infection. Currently in USA we give Sabin in 1st 15 months of life. Testing Treatment? none Killed vacine available, given to travelers to endemic areas. Passive immunization administer Ig Intranasal vaccine w/ killed virus is effective, but only to specific serotype Oral Rehydration Therapy Live attenuated (MMR) - given @ 12-15months Killed Killed Killed Presence of Hep C Ab indicates chronic infection, NOT immunity. PCR assay. Live attenuated vaccine available, given to travelers to endemic areas. Ribavirin, interferon Vaccine available for travelers. Killed vaccine - grown in eggs. Usually a mix of the most common strains - ex 2 A strains and 1 B strain. "Original Antigenic Sin" vaccinated patient responds only to 1st vaccine strain that triggers response. Vaccine given in autumn, after most popular strain determined. Currently, efforts to develop live-attenuated vaccine. Prophylactic amantadine or rimantadine Live, attenuated is being studied. Killed vaccine is ineffective. Aerosolized ribavirin Live, attenuated vaccine (MMR). Safe and effective, given at 12-15months Disease is self-limiting Live, attenuated vaccine (MMR). Safe and effective, given at 12-15months. 2nd dose recommended after 6 years. Clinical diagnosis usually, but new recommendations from CDC are to confirm with labs. (1) Hemagglutination inhibition antibody titers, usually detectable when rash appears, peaks in 3-4 weeks. Fourfold rise is diagnostic. Virus can be isolated from throat washings in first 1-2 days of rash. No vaccine, live-inactivated vaccine trial made disease worse. Clinical diagnosis Hospitalized babies treated with aerosolized ribavirin. If exposed: (1) WASH wound. (2) Passive vaccination - administer immune globulin. (3) PostKilled vaccine - HDCV exposure active vaccine (Human Diploid Cell Vaccine) - Post mortem - Negri bodies in nerve HDCV. Once symptoms triggers humoral response. cells appear, NO cure. CD4 lymphocyte count - tells how far the train is from crashing. Viral load - tells the speed of the train. Triple therapy (HAART Highly Active Anti-Retroviral Therapy): (1) Anti-metabolite AZT, ZDV (thymidine analog) (2) RT inhibitor - ddI, ddC, 3TC, d4T (3) PR inhibitor saquinavir, indinavir, ritonavir, nelfinavir Live attenuated vaccine liscensed in 1998. Shell vial, HI, or PCR assays Acyclovir - phosphorylated by viral thymidine kinase, not by host cell TK, thus incorporated into viral DNA but not host. Effective for herpes encephalitis if given early, shortens fever blister episodes, but not curative. Acyclovir - phosphorylated by viral thymidine kinase, not by host cell TK, thus incorporated into viral DNA but not host. Effective for herpes encephalitis if given early, shortens genital herpes episodes, but not curative. Live attenuated vaccine (Oka strain), since 1995, given by 15 months Immune globulin can be given for immunocompromised w/ chicken pox. Acyclovir for shingles. Immunity after varicella lasts lifetime for most. (1) Heterophil Ab to sheep RBC (2) Abnormal lymphocytes (cytotoxic T Infectious mono - Disease is to EBV-infected B cells) self-limiting Look for virus growth in throat and urine. Also, look for inclusion Live attenuated vaccine in trial bodies in cells found in tissues and (Towne strain) urine. Ganciclovir for immunosuppressed. Foscarnet for CMV retinitis. Vaccinia virus (live attenuated), allowed WHO to eradicate smallpox in 1977. Clinical diagnosis only. Capsid particle w/ no DNA being tested as vaccine. (VLP - Virus Like Particle) Liquid Nitrogen to freeze off. Not curative. Immunosuppression is BAD may promote wart growth. Symptomatic treatment only. Immunoglobulin in immunocompromised. Subunit vaccine - series of 3 injections. Purified HBs-Ag protein is grown in yeast. Safe and effective. Given in 1st 15 months. HBsAg rises after infection, disappears at 4.5 mo. HBeAg (indicates highest period of viral replication) rises at 2wks, falls at 34mo. Symptoms and liver enzymes rise gradually starting at 1mo, fall around 5-6mo. HBcAb (IgG) rises at 1mo, stays up for 6mo or more. HBsAb (IgG) rises at 4mo when HBsAg falls, remains high for life, indicates that infection is cleared and host is now immune. HB D Antigen Passive immunization (immune globulin) administered for postexposure prophylaxis. Interferon and Ribavirin for chronic Hep B.