InfluenzaSlide 2Slide 3Slide 4Slide 5Slide 6Slide 7Slide 8Respiratory Syncytial Virus InfectionSlide 10Slide 11Slide 12Pneumocystis Pneumonia (PCP)Slide 14Slide 15Slide 16Slide 17Influenza•Causative Agent–Orthomyxovirus –Influenza A virus–Infulenza B virus •SS RNA virus •8 linear segments •Enveloped with spikes–H spike–N spikes•Signs and symptoms•Sudden high fever, pharyngitis, congestion, dry cough, headache and myalgia–Acute symptoms decline within a week•Cough, fatigue and generalized weakness may persist•Acquired through respiratory droplets–Attaches via hemagglutinin spikes•Induces phagocytosis and replicates inside cell–Mature viruses bud from host cell–Infected cells die and slough off•Destroys muco-ciliary escalator–Host immunity quickly controls viral spread•New strains due to hemagglutinin and neuraminidase mutations–Antigenic drift and antigenic shift–Avian flu (H5N1)–Swine flu (H1N1)•Epidemiology–Outbreaks occur every year•About 200,000 cases with up to 40,000 deaths•Pandemics have higher than normal morbidity•1918-19 infected ½ the world population with 40 million deathsCritical Swine Flu prevention tip: Don't DO this!•Prevention–Vaccine –New vaccine required every year•Treatment–Antiviral medications–amantidine and rimantidine resistance common–Inhaled zanamivir mist or oral oseltamivir must be taken with in 48 hours–No aspirin for children!Respiratory Syncytial Virus Infection •Most common childhood respiratory disease–Leading respiratory killer of infants •Pathogen–Respiratory syncytial virus (RSV)–Enveloped, -ssRNA Paramyxovirus–Signs and symptoms•Fever, runny nose, and coughing •Wheezing and difficulty breathing may occur–Dusky skin tone •Leading cause of bronchiolitis in children under one•Some children develop croup•May lead to pneumonia if alveoli become involved–Epidemiology•Transmission occurs via respiratory droplet•Highly contagious•Syncytia help viruses evade immune system•Great risk of secondary infection–Prevention •No vaccine •Aseptic technique •Isolation of infected individuals–Treatment •Typically only supportive care•Ribavirin in extreme cases •No Aspirin!Pneumocystis Pneumonia (PCP)•Causative Agent–Pneumocystis jiroveci •Opportunistic fungus•Obligate parasite •Normal respiratory flora for many•Signs and Symptoms:–Difficulty breathing; mild anemia; hypoxia; and fever–Non-productive cough in some cases–In rare cases, extra pulmonary lesions develop in lymph nodes, spleen, liver and bone marrow•Acquired through respiratory droplets•In healthy individuals usually no symptoms–Life long immunity is conferred –Some may remain carriers for life•Fungus multiplies rapidly in immunocompromised patients and extensively colonizes lungs –Causes substantial damage•Epidemiology–Worldwide distribution–75% of healthy children exposed by age five•Based on presence of antibodies–Disease limited to immunocompromised individuals •One of the diagnostic diseases of AIDS•Prevention–Virtually impossible due to ubiquitous nature •Treatment–oral or IV TMP-SMX (combination of trimethoprim and