Constitutional disturbances may present w or wo

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constitutional disturbances -May present w/ or w/o cervical lymphadenopathy & fever -no diagnostic tests for rhinovirus -culture to r/o bacterial pathogens -DDx for the common cold is v. broad -Tx : supportive -Prevention/Control : hygiene, vaccination for specific agents (rhinovirus doesn’t have a vaccination ) Influenza -Segmented, ssRNA -Enveloped, helical nucleocapsid -Orthomyxovirus -Genera (A, B, C) -A: continuously new Ag -B: sporadic cases -C: mild URI -Outer lipoprotein envelope -hemagglutinin (HA) -neuraminidase (NA) -matrix proteins: M1 (structural), M2 (ion channel for uncoating) Ag: internal ribonucleoprotein (group specific), HA/NA (type specific) -non-structural protein (N S1): determines virulence via inhibiting IFN mRNA production -Transmission : resp. droplet -Highest in school-aged kids -Temperate climates in Jan- Feb -Higher morbidity in high-risk groups -deaths more common in kids w/ risk factors (higher %), more deaths occur in healthy kids -Pathogenesis : invades ciliated epithelium – inflammation, necrosis, desquamation -Ag Shift/Drift -Shift: major change, A only, pandemic, infrequent -Drift: minor changes, -Abrupt onset of fever, shaking chills, severe HA, muscle ache, rhinitis, sore throat, cough, prostration -less common: conjunctival injection, abdominal pain, n/v/d -Major complication = bacterial superinfection -Other complications: Reye’s syndrome, myositis, neurologic -Type A: common pneumonia -Type A&B: URI & croup -High Risk of Complications: <2, >65, pregnant, native American, w/ medical conditions, morbidly obese -Perform culture, rapid tests, in first 72 hrs of illness -Rapid test for A&B Ag’s has variable sensitivity & specificity -A&B Ag staining is rapid, but lots of false +/- -Serology: Hemagglutinin inhibition testing – requires 2 serum samples 10-14 days apart - RT-PCR = highest sensitivity & specificity Vaccination - Inactivated : IM, >6mo old, immunocompromised - Live attenuated : intranasal spray, 2-49 yrs -BOTH: annual, 4 week dosing interval, 2A/1B strains, simultaneous w/ other vaccines Drugs - Amantadine/Rimantadine : NOT used - Zanamivir = NA inhibitor for type A & B prophylaxis & Tx; SE = bronchospasm , inhaled - Oseltamivir = NA inhibitor for type A & B prophylaxis & Tx; SE = N/V, oral tablets
Page22 A&B, epidemic, frequent Parainfluenza -RNA -Enveloped -Paramyxovirus -4 types (1, 2, 3, & 4A/B) -Transmission : direct contact, droplets/fomites -Cyclic/distinct pattern - type 1: croup e/o autumn -type 2: same as 1, less common/severe - Type 3: spring & summer -Type 4 – least common -1° infection w/ all by 5y/o -type 3 in infancy -type 1 = MC among 1-5 y/o - MCC of Croup , pneumonia (1), URI / bronchiolitis (1-3) -Type 1 & 2: croup -Type 3: croup, pneumonia & bronchiolitis, mild cold -Type 4A & B: mild cold Inc severity: large inoculum, young, low maternal Ab, immunocompromised, abnormal pulmonary circulation/airway -Culture: detected by hemadsorption - Rapid Ag ID w/ immunofluoro are typically used -Serology: complement fixation, hemadsorption, Hemagglutinin inhibition; Ags in common w/ paramyxoviruses (mumps) -PCR Management : - Mild croup : mist, oral dexamethasone - Moderate croup: racemic epi, oral dexamethasone, observation - Severe croup: racemic Epi,

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