MICR J210 1st Edition Lecture 21Outline of Last Lecture I. Herpes viruses• Herpes simplex I and II virus: cold sores, genital herpes• Varicella zoster virus (VZV): chickenpox, shingles• Epstein-Barr Virus (EBV): infectious mononucleosis• Cytomegalovirus (CMV): CMV mononucleosis II. Adenovirus: conjunctivitis, diarrheaIII. ParvovirusIV. Human papilloma virus (HPV): wartsOutline of Current Lecture I. Poliovirus: PoliomyelitisII. Rhinovirus: Common coldIII. Coxsackievirus and EchovirusesIV. Influenza virus: FluV. Respiratory syncytial virus (RSV)VI. Mumps virus: MumpsVII. Measles virus: MeaslesVIII. Rubella virus: German measlesIX. Rhabdovirus: RabiesX. ArbovirusXI. RotavirusXII. NorovirusXIII. Ebola VirusCurrent Lecture- Polioviruso ss RNA-containing, naked virusThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.o Three serotypes, human is the only hosto Route of infection: Fecal-oral (Virus Sheds in feces)o Symptoms of poliomyelitis: Fever, malaise, sore throat, followed by musclepain and stiffness, followed by paralysis 1-2 days later in about 1% of cases.  Clinical disease is paralysis.  If spinal cord gets infected, may lead to paralysis of legs and/or arms (1/70 in adults, 1/200 in children)- Partial recovery is often seen.  If part of spinal column that enervates the lungs get infected, lung paralysis require'iron lung‘ o TREATMENT: No treatment except for physical therapy to recover functiono PREVENTION: Vaccination: Two types of vaccines are available- 1. Salk vaccine: Injected (used in USA)**o Killed vaccine, protects against all 3 serotypes. o It protects from disease but does not prevent the spreado Need 3 shots 2-18 month age + booster at 4-6 yrs- 2. Sabin vaccine: oral vaccine o Live, attenuated vaccine, protects against all 3 serotypeso Protects from both disease and spread of diseaseo Usually there is life-long immunity. o There is one disadvantage with Sabin - 1 serotype may revert to wild-type virulent polio in 1 in a million vaccinationso Post-Polio syndrome (PPS) A condition that affects polio survivors around 10 to 40 years after recovery from an initial paralytic attack of poliomyelitis virus  PPS is characterized by a further weakening of muscles that were previously affected by the polio infection Some patients experience only minor symptoms, while others develop spinal muscular atrophy Symptoms of PPS include: - Fatigue, - Slowly progressive muscle weakness and possibly muscular atrophy - Difficulty swallowing and breathing- Joint pain and increasing skeletal deformities such as scoliosis- Gradual decline in the ability to carry out activities of daily living- Rhinoviruso ss RNA-containing, naked viruses that cause common cold – The most common cause of common cold!  from the Greek word rhin, meaning "nose"o About 140 serotypes that cause 30-50% of the upper respiratory tract infectionso Usually cause 3-5 infections/year/persono Transmitted by personal contact (sneeze into hand, shake hands, eat a sandwich- 'Friendly disease')o Incubation time - 2-3 dayso Symptoms of common cold: Cough, inflammation of the nasal cavity, sore throat, Headache, and no fever usuallyo Treatment: Just like with any other common cold virus, there are no treatments that can kill a rhinovirus. Therefore, rhinovirus treatment involves relieving symptoms as the body fights the rhinovirus infection o Prevention There is no vaccine because of the mildness of the disease and the large number of serotypes involved. You will need to get 140 colds to get immunity There are several ways you can reduce your chances of getting a rhinovirus infection. Suggestions for rhinovirus prevention include:- Washing your hands regularly - Keeping your hands away from your nose, mouth, and eyes - Limiting exposure to infected people - Practicing healthy habits - Using disinfectants- Enteroviruseso Enteroviruses: family of non-enveloped small RNA viruses that live in the human digestive tract and are the second most common viral infectious agents in humans (Rhinovirus is the 1st one) and ordinarily its members are transmitted by the fecal-oral route o Enteroviruses members includes viruses such as:  Coxackieviruses, Polioviruses, Echoviruses and Hepatitis A virus Coxsackieviruses(named after a town in NY state) are Two types:  Coxsackievirus A (23 serotypes) Coxsackievirus B (6 serotypes) ECHOVIRUS (31 serotypes) - Highly infectious, and its primary target is children- Among the leading causes of acute febrile illness in infants and young children- The most common cause of aseptic meningitis- Coxsackievirus and Echoviruso DISEASES:  Group A Coxsackievirusesgenerally tend to infect the skin and mucous membranes, causing:- Herpanginao An acute febrile illness associated with small vesicular or ulcerative lesions on the posterior oropharyngeal structures. - Acute hemorrhagic conjunctivitis (AHC)o Conjunctival congestion, vascular dilatation, and onset of edema, a prominent hemorrhagic component soon appears that is characteristic of this infection- Hand-foot-and-mouth (HFM) diseaseo An acute illness that presents as a vesicular lesions in the mouth (Herpangina) and can also involve the hands, feet, buttocks, and/or genitalia Group B Coxsackieviruses: Generally tend to infect the heart, pleura, causing:- Pleurodyniao The disease features fever and intense abdominal and chest pains with headache. The chest pain is typically worsened by breathing or coughing like pleurisy (stabbing pain upon breathing). The illness lasts 4-7 days, and is self-limiting Both Groups A and B Coxsackievirusescan cause:- Aseptic meningitis, myocarditis, pericarditis (inflammation of heart)o Most older children and adults usually recover, but it can be fatal in neonates- The development of insulin-dependent diabetes (IDDM) has recently been associated with recent enteroviral infection, particularly Coxsackievirus B infection. This relationship is currently being studied further TREATMENT of Coxsackievirus infections- There are no drugs for treatment, and there are no vaccines. Provide supportive care and bed-rest- Influenza Viruso Helical, ss RNA-containing (8 segments), enveloped viruso Three serotypes A, B, Co Serotype A is associated with pandemicso Serotype B cause Local epidemicso Serotype C rarely causes disease