Transcript Influenza
Upper Respiratory Tract Infections and Influenza Upper Respiratory Tract Infections • • • • • • • • Common cold Pharyngitis Acute laryngitis Acute laryngothracheobron chitis Otitis externa Otitis media Mastoiditis Acute sinusitis Common cold • Generally mild, self-limiting • Many viruses can cause similar clinical picture • 2-4 times/year in adults 6-8 years in children. • September to August • Transmitted with respiratory secretions. Common Cold: etiology Virus • • • • • • • • Antigenic type Rhinovirus Coronavirus Parainfluenza virus RSV Influenza virus Adenovirus Undefined viruses Group A beta-hemolytic strep. 101 >3 4 2 3 47 % 30-40 >10 10 10 10-15 5 25-30 5-10 Common Cold • Clinical: nasal congestion, sneezing, sore throat, decreased taste • Complications: acute sinusitis and acute otitis media Common Cold: Treatment • NO ANTIBIOTICS. • Drops and sprays with 0.25-0.5% phenilephin or 1% ephedrine • Antitussives, antipyretics • Bed rest • High dose vitamin C? Acute Pharyngitis • Majority (40%) due to viruses • Group A beta-hemolytic streptococcus 15-30% • May associate: – – – – – – – Common cold Influenza Herpetic Infectious mononucleosis Vincent’s angina Peritonsillar abscess Dyphteria Acute Pharyngitis • The majority (75%) are given antibiotics – To prevent rheumatic fever – Patient’s expectations! Acute Pharyngitis: diagnosis • Yielding GABHS in throat swab culture is diagnostic in 90-95% • Acute infection-carrier? • Clinical features and rapid antigen tests are helpful Acute pharyngitid: Dx • Clinical features: – – – – Tonsillary exudate Painfull anterior cervical lymphadenopathy Absence of cough Fever *any 3, sensitivity and specificity around 75% CDC Position Paper, 2001 Acute Pharyngitis: Throat culture Exam.: GABHS Exam.: EBV EBV Acute Pharyngitis: Tx • In GABHS, it decreases complications, decreases the course of the disease by 1-2 days Acute pharyngitis: Tx 1. Look for 4 criteria: a. fever b. tonsillary exudate, c. No cough d. Painful anterior cervical LAP. 2. 0-1 criterion: no lab study, no antibiotics tx. CDC Position Paper, 2001. Acute Pharyngitis: Tx 3. If >2 criteria: you may, a. For those with 2,3, or 4 criteria, study rapid antigen test, and if positive give antibiotics b. For those with 2 or 3, study rapid antigen test, and if positive or with 4 criteria c. No further test is needed, for those with For those 3, or 4 criteria give antibiotics CDC Clinical Practice Guideline, 2001. Acute Pharyngitis • First choice – Benzathin penicillin: 1.2 MU, IM, single dose – Penicillin V: 500 mg, 2-3 times in a day, for 10 days • Penicillin allergy – Erythromycine Acute Rhinosinusitis • Frequently antibiotics are given (85-98%). • Almost always follows an upper RTI (inflammation in mucosa and obstruction of ostia of sinuses) • Acute sinusitis lasts <4 weeks Viscosity and content of secretions Normal Mucus content Normal Mucus absorbtion Normal Mucus secretion Normal OSTIUM OPEN Mucociliary activity Normal Systemic Host Defense Normal Acute sinusitis: Etiology • • • • • • • • S. pneumoniae H. influenzae Anaerobs S. aureus S. pyogenes M. catarrhalis Gram-negative bacteria Viruses %31 %20 %6 %4 %2 %2 %5 %30 Viral-Bacterial Rhinosinusitis • Diagnosis: Sinus sampling • Clinical clues for bacterial sinusitis: – Purulant nasal discharge, unilateral maxillary or fascial pain – Unilateral sinus tenderness – Deterioration of symptoms after initial improvement Plain x-ray • Full opacity or air-fluid level specificity 85% (76-91%) • Mucosal thickening specificity 4050%. Treatment 1. If not complicated, no need for X-ray. Consider clinical clues 2. If symptoms are mild to moderate, antibiotics are not given 3. Severe or persisting moderate symptoms are treated with antibiotics CDC Clinical Practice Guideline, 2001. Tx • Amoxicillin 500 mg x 3 (10-14 days) • Amox/clav. 500/125 mg X 3 (1014 days) • Amp/sul. 375-750 mg x 2 (10-14 day) • Cefuroxim axetil 250 mg X 2 (1014 day) • Clarithromycine 500mg X 2 (10-14 days) • Azithromycine 500 mg (5 days) • Levofloxacin 500mg (10-14 days Acute Otitis Media • <15 y, a frequent cause of admission to doctor • <3 y, most frequent – 2/3 children >1, 1/3 children >3 times • Hearing loss, cholesteatoma, chronic perforation Acute Otitis Media: Etiology S. pneumoniae 32 H. influenzae 10 GABHS Moraxella 3 40 25 Unknown Acute Otitis Media Clinical features and diagnosis • • • • • Ear pain, discharge, hearing loss. Fever, irritability Erythema on tympanic membrane Fluid accumulation in middle ear Tympanic f. sampling in selected cases – Severe disease – Unresponse to antibiotics within 48-72 h. – Immunsuppressives Acute Otitis Media: Tx • Amoxicillin • Beta-laktamase inhibitors – SAM, CAM • 2nd gen. Cephalosporins – Cefuroxim, cefaclor, cefprozil, loracarbef • Macrolides – Clarithromycine, azithromycine • Antihistamines Influenza 1918 , Oakland 1918, Iowa Ryan JR. Pandemic influenza İnfluenza Nedir? Influenza • A highly contagious respiratory infection caused by Influenza A and B • Symptoms: – High fever, cough, myalgias, fatigue, headache, sore throat and nasal congestion • May last 1-2 week • Affects individuals, families, populations, and economy of the countries • May cause significant mortality in vulnerable patients Nicholson et al. Lancet 2003; 362: 1733–45. • Incubation period 1-2 days • A sudden beginning • May cause a mild hyperemia in throat. UpToDate 2009 • Improvement: 2-5 days (>1 week in some) • In some, fatigue, tiredness may last for weeks Differential Dx • Common cold Influenza & Common Cold Symptom Influenza Common Cold Fever Generally high, 3-4 days unusual Headache Yes Unusual Generalized pain Usually, generally severe Mild Fatigue, tiredness May last 2-3 weeks Moderate Severe tiredness Early and severe Never Nasal congestion/ sore throat Sometimes Common Sneezing Sometimes Usual Chest discomfort General, may be severe Mild-to-moderate Cough Cough without sputum Very rarely National Institute of Allergy and Infectious Diseases Common cold etiology • 6 virus family – Orthomyxoviridae (Influenza virus) – Paramyxoviridae (Parainfluenza, RSV) – Picornaviridae (Rhinovirus-89 tip, Coxsackievirus, Echovirus, Poliovirus) – Coronaviridae (Coronavirus) – Adenoviridae (Adenovirus) – Herpetoviridae (HSV, EBV) Complications • Pneumonia: most frequent • Generally seen in those with underlying disorders – – – – – – – Cardiovascular Pulmonary Renal dis. DM Immunosuppressives Those in long term care >50 y. Pneumonia • Primary (influenza pneumonia) – A gradual increase in signs and symptoms (high fever, dispnea, cyanosis) • Secondary (bacterial) – Deterioration after a temporary improvement – ¼ of death due to influenza – Pnomococci, staph. 22 ,F, SLE 76, F, Cerebrovascular disease Myositis, rhabdomyolysis • Myalgias are frequent • True myositis is rare • Tenderness and edema • CNS complications: encephalitis, transverse myelitis, aseptic meningitis, Guillain-Barré syndrome… • Myocarditis, pericarditis İnfluenza Çok Bulaşıcıdır transmission Cough, sneezing Hand contact, utensils, Influenza period December to April Every season in tropics Diagnosis • During Outbreak • Without outbreak During outbreak • Clinical findings fever, cough, fatigue No sneezing In a study of 3744 adults, Considering fever and cough within 48 hours, 80% Arch Intern Med 2000;160:3243 Without Outbreak • Clinical findings are not diagnostic! In a study of 497 elderly patients with upper resp. tract infection: 43% yielded the etiology rhinovirus (52%), coronavirus (26%), Influenza A and B (10%) BMJ 1997;315:1060 Without Outbreak • Serology • Rapid tests (IF, ELISA, PCR) • Virus culture • Research, epidemiology… Influenza Neuraminidase Hemaglutinin RNA M2 protein (type A ) Hemaglutinin binds to sialic acid Antigenic shift Tx? • • • • • Paracethamol Non-steroids (No aspirin-Reye’s syndrome) Antitussives Specific antivirals – Adamantans (amantadin, rimantadin-resistance) – Neuraminidase inh. (oseltamivir, zanamivir) Specific Antivirals • • • • Effective against Influenza A and B Decreases hospital stay Decreases severity and complication rate Decreases mortality Arch Intern Med 2003;163:1667 Antivir Ther 2007;12:501 Clin Infect Dis 2007;45:1568 J Am Geriatr Soc 2002;50:608 Indications • Influenza pneumonia • Influenza pneumonia with bacterial penumonia • Those with high risk to complications – – – – – – – – Those living in care centers Pulmonary dis. Cardiovascular dis. Cancer Chronic renal failure DM Immunosuppressed Neurologic dis. MMWR Recomm Reb 2008;57:1 • Within 48 h: more effective • 3rd trimester pregnancy • 2nd timester (plus risk factors) Obstet Gynecol 2006;107:1315 Control • Mask • HAND WASHING 2009H1N1-Swine flu • 2 swine -1 bird-1 human • Can be transmitted from human-to-human • Symptoms – – – – – – – – fever Cough Sore throat Nasal congestion/rhinitis Headache Chills Myalgias Nausea/vomiting • Contamination – 1 day before overt disease and following 5/7 days • Tx – Like seasonal flu.