Published on October 23, 2007
Slide1: The Elderly Adult Patient with Fever Joel Spalter, MD Assistant Professor, Department of Internal Medicine Chair, Division of Infectious Disease Nova Southeastern University College of Osteopathic Medicine © 2005 Slide2: Fever and Febrile Illnesses in the Elderly CDC Slide3: Outline (1) Temperature and Fever in the Elderly. Functional Decline and Other Indicators of Infection in the Elderly. Antibiotic Use in Long Term Care Facilities (LTCFs), Bacterial Resistance, and Sepsis in the Elderly. Infectious and Non-Infectious Causes of Fever in the Elderly. Polymyalgia Rheumatica (PMR) and Temporal Arteritis (TA) Drug Fever. Pulmonary Emboli. Slide4: Outline (2) 8) Endocarditis. 9) Tuberculosis (TB). 10) Influenza. 11) West Nile Fever. Slide5: Definitions of Normal Temperature and Fever in Immune Competent Adults: Maximum Normal Oral Temperature at 6A.M. is 98.9oF, at 4 P.M. it is 99.9oF (99th Percentile) Rectal Temperature is 1oF Higher. Normal Circadian Rhythm – 0.9oF Fever is an Oral Temperature of >99.0oF in the Morning or >100.0oF at any Other Time Slide6: In the Elderly, Normal Temperatures are Lower than they are in the younger adult and the Definition of Fever must be changed in order to make the Presence or Absence of Fever more Useful Diagnostically. Many Illnesses that are “Febrile Illnesses” occur in the Elderly with little or no “Fever.” Fever in the Elderly can be Defined as a Persistent Oral Temperature of > 99ºF or a Persistent Rectal Temperature of > 99.5ºF* *Dean C. Norman, Fever in the Elderly, Clin Infect Dis, 2000; 31, 148-51. Slide7: Study of Temperature in 111 NH Patients with Infection:* Oral Temperature Sensitivity Specificity Defined As Fever: > 101ºF 40% 99% > 100ºF 70% 98% > 99ºF 83% 89% 40% of infected patients had a temperature of > 101 30% of infected patients had a temperature of 100 to 100.9 13% of infected patients had a temperature of 99 to 99.9 17% of infected patients had a temperature of < 99. 11% of uninfected patients had temperature > 99. * Castle SC, et al, Lowering the temperature criterion improves detection of infections in nursing home residents. Aging Immunol Infect Dis 1993, 4:67-76. Slide8: Functional Decline as a Sign of Infection* Sixty-five episodes of functional decline (new or increased confusion, incontinence, falling, loss of mobility, or failure to cooperate with rehabilitation) in 143 veterans over a six month interval. Fifty of the 65 (77%) of episodes of functional decline were associated with infection. Death rate halved during the study and returned to baseline after the study concluded. Attention to early symptoms and signs of infection improved survival. *Berman P, Hogan DB, Fox RA. The atypical presentation of infection in old age. Age Ageing. 1987 Jul;16(4):201-7. Slide9: Predicting Bacterial Infection in the Elderly* Two hundred twenty-one patients aged between 70 and 99 presenting to an ER were screened for infection with assessment of fever (> 99.5ºF), leukocytosis (> 14,000mm3), elevated bandemia (> 6%) and elevated total band count (> 1500/μL). 33 patients had documented bacterial infection. Fever had a sensitivity of 52% for infection. *Utility of fever, white blood cells, and differential count in predicting bacterial infections in the elderly. Wasserman M, Levinstein M, Keller E, Lee S, Yoshikawa TT. J Am Geriatr Soc. 1989 Jun;37(6):537-43 Slide10: Odds of the Screened Parameters as Indicators of Infection were Obtained. Finding: Odds of Bacterial Infection: Temperature > 99.5°F 3.6 Total Band Count > 1500 14.5 Bands > 6% 4.7 Total WBC > 14,000 3.7 Odds = True Positive/False Positive = Sensitivity/(1-Specificity) Probability (PPV) = Odds/(1+Odds) Slide11: In the Elderly There Are Two Sides to the Problem of Fever: Elderly patients have a less robust febrile response than younger patients. When elderly adults have a temperature that is elevated to a level that is considered to represent fever in a younger adult, the cause is very likely to be severe. Slide12: Antibiotic Usage in the LTCF: 1) 4100 patients in 53 LTCFs observed for a year. 2) 54% received one or more courses of antibiotics during the year. 3) 8% on antibiotic the day the study began. 4) 44% of patients had a physical exam at the start of their antibiotic. 5) 1.7 courses of antibiotics/resident/year. 6) Consensus criteria for minimal diagnostic evaluation were met in only 11% of antibiotic use.** **Warren JW et al, Incidence and characteristics of antibiotic use in aged nursing home patients. J Am Geriatric Soc 1991;39:963-72. Slide13: Antibiotic Resistant Bacteria (ARB) Handwashing: 1) Rates of hand-washing in 2800 instances in which it was required: Nurses 52% Nursing Aides 47% Doctors 30%* 2) LTCF patients become colonized by ARB which can then be spread among them. *Pittet D et al, Compliance with handwashing in a teaching hospital Infection Control Program. Ann Intern Med; 1999, 130:126-130. NIH Ignaz Semmelweis US GS Slide14: Sepsis Hospitalizations of the Elderly* 1986 1997 Total Medicare Admissions 91,000 219,000 for Sepsis Rate/1000 Medicare 3.42 7.42 Beneficiaries 30-Day Post Admission Sepsis Mortality 24.7% (All Sources) 30-Day Post Admission Sepsis Mortality 37.2% (Decubitus Ulcer Source) 30-Day Post Admission Sepsis Mortality 33.6% (Pneumonia Source) *McBean M & Rajamani S, JID 2001;183:596-603 Slide15: Diagnoses in the Elderly that are Concerns as Causes of Fever or Febrile Illnesses Fever Not Due to Fever Due to Infection: Infection: PMR 1) Endocarditis 2) Drug Fever 2) Tuberculosis 3) Pulmonary Emboli 3) Pneumococcal Pneumonia 4) Influenza 5) West Nile Fever Italics = Will be discussed under cough Slide16: Temporal Arteritis (TA) (Cranial Arteritis, Giant Cell Arteritis) and Polymyalgia Rheumatica (PMR) © University of Alabama at Birmingham, Dept of Pathology Slide17: Temporal Arteritis (TA) is a systemic inflammation of medium and large arteries: Found in patients older than 50. Women, Scandinavian lineage. 2) Incidence 1/15,000/year –1/3,000/yr –Minnesota. 3) 16% of FUO in Patients Older Than 65. Most common single diagnosis in FUO in those aged 65 or more. Fever, Elevated ESR, Anemia, Headache, Night Sweats, Malaise, Weight Loss, Tender Temporal Artery, Scalp Pain, Jaw Claudication. Irreversible Optic Neuropathy with Blindness Slide18: 6) Normal WBC before prednisone. Normal CPK. 7) Risk of Thoracic Aortic Aneurysm (15%). 8) Treatment is corticosteroids (prednisone 40-60 mg/day). 9) 50% of patients with TA have PMR. © Slice of Life and Suzanne S. Stensaas NIH Optic Neuritis (TA) Slide19: Giant Cell Aortitis in Temporal Arteritis © Univ. of AL at Birmingham, Dept. of Path Slide20: © Univ. of AL at Birmingham, Dept. of Path Temporal Artery in Temporal Arteritis Slide21: PMR: 1) Incidence 1/1700/year in patients over 50 in Olmstead County, MN (Mayo Clinic). Women:Men = 2:1. Persistent Symmetrical Neck, Shoulder Girdle, and Pelvic Girdle Pain and Morning Stiffness lasting for more than 30 minutes a day for a month. No Muscle Weakness. Fever, Anorexia, Weight Loss, Malaise. Slide22: 5) Anemia, Elevated ESR (>40), NormalMuscle Enzymes. 6) Treatment is corticosteroids (prednisone 10-20 mg/day) 7) A dramatic response is expected in 3 days. 50% of patients with TA have PMR 15% of patients with PMR have TA PMR TA TA PMR Slide23: Drug Fever – Mechanisms Altered Thermoregulatory Mechanisms Administration Related Pharmacologic Action Idiosyncratic Reaction Hypersensitivity Reaction (Most Common) Incidence unknown but the more drugs, the more likely. Recognition may avoid needless evaluation and be easily treated – Stop the drug. Slide24: The average annual number of ﬁlled prescriptions for older Americans increased from 18 prescriptions in 1992 to 30 prescriptions in 2000 (before Medicare D). Slide25: 1) Alteration of Thermoregulatory Mechanisms Thyroid increases metabolic activity. Sympathomimetics (Cocaine, Epinephrine, & Amphetamines) induce heat generation in CNS and reduce heat dissipation by vasoconstriction. Anticholinergics (Atropine, Tricyclics, Antihistamines, & Phenothiazines) reduce heat dissipation by reducing sweating. Cimetidine – Blocks Hypothalamic H2 Receptors. Slide26: Drug Administration Impurity – Vancomycin (Previously) Intrinsic Pyrogen – Amphotericin, Bleomycin Phlebitis from IV drug & abscess from IM drug 3) Pharmacologic Effect Jarisch-Herxheimer – Occurs and resolves in 24 hours, with myalgias, chills, and hypotension. (Syphilis, Borreliosis, Leptospirosis, Trypanosomiasis, Cancer) Slide27: 4) Idiosyncratic Reaction Malignant Hyperthermia (Inhaled Anesthetics due to muscle Ca++ dysregulation – Muscular rigidity, arrythmia) Neuroleptic Malignant Syndrome (Antipsychotics – Dopaminergic Receptor Blockade Muscular rigidity, arrythmia) G-6-PD deficiency (Sulfonamides, quinidine, nitrofurantoin, antimalarials due to release of pyrogens by hemolyzed RBCs.) Slide28: 5) Hypersensitivity Most common and prolonged of drug fevers. Usually occur after some time on the drug. Minority of cases are with rash, serum sickness, or lupus syndrome. Re-administration of drug causes accelerated reaction. Antibody to the drug does not confirm the diagnosis and absence of antibody does not exclude the diagnosis. Slide29: Drug Fever – Symptoms and Signs Fever usually 102°F-104°F. Patient often looks “too well.” Relative Bradycardia may be present (Failure of pulse to rise 10 beats over 100 for each 1°F rise in temperature over 101). Sino-atrial disease, β-blockers, typhoid fever, leptospirosis, brucellosis and some other non-bacterial infections also cause Relative Bradycardia. 4) Eosinophilia, leukocytosis, and elevated ESR may or may not be present. 5) Definitive diagnosis is by stopping the drug with cessation of fever within 72 hours. Slide30: Pulmonary Embolism ©xray2000.co.uk Slide31: Chronic Pulmonary Embolic Disease Are 4% of FUOs. 2) Are emboli from venous thrombosis in pelvis or proximal thigh. 3) Cause progressive right ventricular dysfunction. 4) Obesity, surgery, immobilization predispose. 5) Dyspnea & tachypnea are the most common findings. Normal or low PaO2 and low PaCO2. 6) Pleuritic chest pain and hemoptysis may occur. 7) D-dimer (reflecting plasmin breakdown of fibrin) >500ng/ml has a sensitivity of 94.6% and a negative predictive value of 99.6%. Slide32: Pulmonary Embolus RLL (V/Q Imbalance) (With Pulmonary Emboli V/Q imbalance is normal ventilation with deficient perfusion.) SI, QIII, TIII – Sinus Tachycardia Slide33: Endocarditis in the Elderly Slide34: Image donated by: Professor P J Berry University of Bristol, Department of Pathology & Microbiology © Bristol biomedical Image Archive, Univ. of Bristol Aortic Valve Endocarditis Image donated by: Professor Ian Lauder Leicester University, Department of Pathology © Bristol biomedical Image Archive, Univ. of Bristol ←Vegetation Slide35: Infective Endocarditis (IE) Epidemiology In 1940s mean age was 35 with 10% over 60. Now mean age is 55 with 50% over 60. Reasons for the change: ↓ARF, ↑Calcific valve disease, ↑intravenous devices and valve surgery. Men:Women = 2-8:1 in patients over 60. More than 80% of IE in elderly is caused by Streptococci (↓) or Staphylococci. (→) CDC CDC Slide36: Native Valve Infective Endocarditis in Elderly Fever (> 100.4 Orally x2) 85% Altered Mental State or Stroke 38% CHF 48% Emboli 40% Arrhythmia 22% Valvular Surgery (Due to IE) 33% Death 26% Note Fever is common but not universal. Only death rate is less in the Young (13%). Gagliardi JP, et al CID, 1998;26:1165-8, Netzer ROM, et al, CID 1999;28:933-4 Slide37: Endocarditis’ presenting symptoms may be malaise, anorexia, weight loss, & lethargy, which may be attributed to “old age.” Positive Blood Cultures in ~98% if 3 sets are done without prior antibiotics. Bacteremia is continuous. Slide38: Prosthetic Valve Endocarditis (PVE) 1) 75,000 prosthetic valves placed a year in the US. 2) Bioprosthetic are less durable than mechanical valves but do not need long term anticoagulation. 3) PVE incidence on bioprosthetic valves is ~ 0.5%/yr for mitral and 0.9%/yr for aortic valves. 4) PVE incidence on mechanical valves is~ 0.2%/yr for mitral and 0.3% for aortic valves. 5) Early PVE within 2 months of surgery is caused by nosocomial organisms. 6) Late PVE is caused by the same organisms as native valve endocarditis. Slide39: NASA What is the probability of getting PVE over the 20 years after the valve replacement if the yearly incidence is 0.3%? 0.7%? Answers: 1-(.997)20 = .06. and 1-(.993)20 = .13. Put the yearly PVE incidence into perspective. Slide40: Streptococcus bovis endocarditis is indicative of colonic polyps or cancer until evaluation excludes them. Prevalence of colonic neoplasia in patients with Strep bovis endocarditis = 77%. NOAA Slide41: Boards: In a patient with a clinical diagnosis of IE, a Gram + coccus in chains is recovered from 3/3 blood cultures. Testing shows it to be Lancefield group D. It is inhibited by 0.05µg/ml of penicillin. You would do? And would not be surprised to find? www.xray2000.co.uk Slide42: Professor Ian Lauder Donor organisation: Leicester University, Department of Pathology © Bristol biomedical Image Archive, Univ. of Bristol 1/3 of Patients with Infective Endocarditis (IE) have Cerebral Emboli. 3% of all Cerebral Emboli are due to IE. Cerebral Embolus can result in Abscess, Infarction, Hemorrhage, or Arteritis. Infarction → Slide43: © Slice of Life & Suzanne S. Stensaas Septic Emboli to Brain SBE ↓ Neurologic Events occur in 20-40% of Patients with IE. In half, the Neurological Event is the First Event. Therefore: A Febrile Stroke is Endocarditis until proven otherwise. Slide44: Conjunctival Petechiae in Endocarditis Josh Fierer, M.D ©2002, The School of Medicine of the University of California, San Diego Slide45: Janeway Lesions – Painless, Erythematous Macules Josh Fierer, M.D Copyright ©2002, The School of Medicine of the University of California, San Diego Slide46: Osler’s Nodes – Painful, Erythematous, Nodules Josh Fierer, M.D Copyright ©2002, The School of Medicine of the University of California, San Diego Slide47: Treatment of Selected Etiologies of Infective Endocarditis Streptococcus sensitive to < 0.1μg/mL of penicillin – 18,000,000 units of penicillin or 2 grams of ceftriaxone a day intravenously for 4 weeks. Enterococcus – Penicillin as above or ampicillin 12 grams a day, & gentamicin intravenously for 4 to 6 weeks. MSSA – 12 grams nafcillin a day IV for 4-6 weeks + gentamicin MRSA or MRSE – Vancomycin + gentamicin IV for 4-8 weeks + oral rifampin. Slide48: CDC March 16, 1992 Slide49: TB’s Dangerous Secrets 1) TB is an airborne disease that infects the lungs. 2) You get it by breathing. A WHO official called it “Ebola with wings.” 3) One in 3 of the World’s people is infected with latent TB, including 15,000,000 in the US. 4) Worldwide there are 8.4 million new active infectious cases of TB each year. 5) TB kills 2 million people every year. More this year than in any prior year in history. 6) Until 1950s, TB was a leading cause of death in the industrialized world, as it still is today everywhere else. Slide50: Famous People Who Died of Tuberculosis Person Year of Death Age Eleanor Roosevelt 1962 76 John Keats 1821 26 Henry David Thoreau 1862 45 Feodor Dostoyevsky 1881 60 Anton Chekhov 1904 44 Franz Kafka 1924 41 Katherine Mansfield 1923 35 D.H. Lawrence 1930 45 Slide51: Thomas Wolfe 1938 37 George Orwell 1950 47 Rene Laennec 1826 45 (invented the stethoscope) Doc Holliday 1887 36 Frederic Chopin 1849 39 Stephen Foster 1864 38 Amadeo Modigliani 1920 36 Vivien Leigh 1967 54 Before 1950, 50% of AFB Smear Positive TB Patients were Dead within 2 Years. Isoniazid (INH) was introduced in 1952. Slide52: Symptomatic TB Incidence is Highest in Persons Aged 65 and Over in the US 8.8 Slide53: The remains of an 1843 experimental tuberculosis hospital in Mammoth Cave. NPS Slide54: Nursing Homes, the Elderly, and Tuberculosis: LTBI – Latent tuberculosis infection, manifested by a Positive Tuberculin reaction but no symptoms, develops in Nursing Homes. Twelve percent of patients were PPD + on admission to NH but ~ 21% were PPD + when tested an average of 30 months after admission.* * Tuberculosis as an endemic and nosocomial infection among the elderly in nursing homes, Stead, et al, NEJM, v 312:1483-1487, June 6, 1985 Slide55: 2) Active Tuberculosis goes undiagnosed in the Elderly. From 1985 to 1988, 5.1 percent of TB cases reported in the United States were diagnosed at death. Nineteen (19%) percent of cases among patients 85 years and older were diagnosed at death.** **Tuberculosis diagnosed at death in the United States, HL Rieder, et al Chest, Vol 100, 678-681 Slide56: 3) Unrecognized TB can spread to the community. A 91 year old died of undiagnosed TB, infecting 80 persons – 52 employees, 23 residents, and 1 visitor got LTBI. One NH resident, 1 NH employee, 1 NH visitor, and 1 hospital employee got symptomatic TB. The details of the index case are informative.*** ***Unrecognized Tuberculosis in a Nursing Home Causing Death with Spread of Tuberculosis to the Community, Ijaz K, et al, JAGS v50:1213-1218, 2002 Slide57: The Index Case A 91 year old woman had been admitted to the NH in 1995, in relatively good health. She was then ambulatory with a negative PPD. Two years after admission she developed a productive cough and became too weak to walk. Over the next 8 months she was seen in the local ER twice and admitted to the hospital 4 times and treated for “pneumonia.” Serial chest x-rays over the 8 months showed an enlarging RUL cavitary infiltrate. TB was never considered as a diagnosis and no diagnostic studies relative to tuberculosis were done. Cough was not helped by the treatment for pneumonia. Slide58: CXR as described in Index Case Slide59: The genotype of the M. tuberculosis from the hospital worker with tuberculosis (worked at the hospital where the index case was hospitalized 4 times), from the visitor to the NH (met the index case when visiting his wife in the NH), and from both the NH employee and the NH resident matched exactly the genotype of the organism from the index case. The hospital worker and the visitor became symptomatic with TB while living in different cities from where the NH was located. Slide60: Testing for and Treating of Tuberculosis and LTBI in the Elderly Conclusions: PPD test NH residents yearly and treat for LTBI or tuberculosis, as indicated, if PPD is found to be positive. 2) Certainly consider tuberculosis in any NH/Elderly patient with chronic cough, + PPD, upper lobe CXR infiltrates, and weight loss, or any “pneumonia” that does not clear. Slide61: Treatment Regimens for LTBI: INH 300mg/Day x 9 Months (Pyridoxine 50mg/ day) Rifampin 600mg/Day x 4 Months Adverse Event Data and Revised American Thoracic Society/CDC Recommendations – Against the Use of Rifampin and Pyrazinamide for Treatment of Latent Tuberculosis Infection, 2003 MMWR (Fatal Hepatitis) Slide62: Sputum Smear – Positive for AFB. Requires ~ 5000 –10,000 AFB/μL. Sensitivity ~ 50-60%. Culture of M. tuberculosis on Lowenstein-Jensen medium. Requires ~ 10-100 AFB/μL. Sensitivity ~ 80%. CDC CDC Slide63: Comparison of Symptoms and Signs of Pulmonary Tuberculosis in the Elderly and Younger Adults** Adults Aged Adults Aged 16-64 65 and Older PPD > 10mm* 86% 63% Fever* 36% 22% Hemoptysis* 19% 6% Night Sweats* 33% 13% Miliary Xray Pattern* 0.7% 7% * p < .05; **Chest, July 1994, v106, pp28, Korzeniewska-Kosela et al, Tuberculosis in Young Adults and the Elderly Slide64: Symptoms and Signs of Pulmonary Tuberculosis in the Elderly: Cough 45% PPD + 63% Weight Loss 35% Fever 22% Dyspnea 23% Upper Lobe Xray Changes 55% (Reactivation Pattern) Pleural Effusion with 20% Parenchymal Changes (Primary Pattern) Slide65: ↑↑ Reactivation Tuberculosis – Cavity ↑↑ Primary Tuberculosis of Upper Lobes – Diffuse Alveolar Infiltrates Slide66: Miliary TB USFWS Millet Slide67: ©Univ. of AL at Birmingham, Dept. of Path. Liver with Miliary Tuberculosis Slide68: We will meet tuberculosis again in the lecture on HIV/AIDS and cough since AIDS and tuberculosis represent a Co-Epidemic. Slide69: Influenza Pearl Buck USDA USDA CIA NPS FWS Slide70: Epidemiology – 1) Aquatic birds are the source of influenza viruses for all other species. 2) Pigs are susceptible to both human and avian influenza viruses. 3) The segmented RNA of influenza viruses assorts to produce novel genes and hemagglutinins (H) and neuraminidases (N) especially when cells are infected simultaneously by more than one influenza A virus. Slide71: 4) Asymptomatic infection and prolonged influenza virus excretion occur in pigs. 5) The H and N antigens of Influenza A undergo major changes – Antigenic Shifts – that are associated with pandemics, and more minor changes – Antigenic Drifts. 6) Influenza A viruses are characterized by their H and N antigens. The “bird flu” now spreading west across the Ural Mountains from Siberian to European Russia (August, 2005) is H5N1. Influenza A has 16 H types and 9 N types. Slide72: Pathogenesis and Immunity – Hemagglutinins bind virus to the cell and Neuraminidases aid release of virus from the cell after replication. Incubation period is 1-3 days with rapid extension from infected to adjacent respiratory epithelial cells. Systemic symptoms – fever, headache, myalgias – are due to cytokines. Virus is rare outside of the respiratory tract. Viral shedding occurs from the respiratory tract, usually only for 2-5 days. Slide73: Manifestations – Rapid rise of fever that falls in less than a week. Sore throat, cough, substernal pain, photophobia. Chest examination is essentially normal in uncomplicated influenza. 4) Dyspnea, hypoxia, cyanosis, or signs of consolidation suggest a complicating process. Slide74: Complications – Occur in those older than 64, pregnant, and with chronic cardio-pulmonary or renal disease or DM. Most common complication is pneumonia, either primary influenza pneumonia or bacterial (Staphylococcal or Pneumococcal) pneumonia. Bacterial pneumonia is more common than primary influenza pneumonia. Slide75: S. aureus Str. pneumoniae CDC Slide76: Time Course of Illness: Uncomplicated Influenza: Acute onset of fever & systemic symptoms (headache, myalgia, chills, malaise, cough, sore throat). Fever for 2-3 days. Sore throat and cough may lag systemic symptoms and last 1-2 weeks. Physical findings of pharynx and chest are minimal. Primary Influenza Pneumonia: Relentless and continuous illness with fever, dyspnea, and cyanosis, crackles, and diffuse infiltrates on CXR. Slide77: Time Course of Illness: 3) Secondary Bacterial Pneumonia: Improvement for 2-3 days followed by reappearance of fever, cough, purulent sputum, and physical and CXR findings of consolidation. Etiologic diagnosis can often be made on sputum Gram stain. Slide78: Treatment – Supportive, avoid aspirin especially with influenza type B – Reye’s Syndrome (Children < 18). 2) Specific therapy – Amantadine and Rimantadine for Influenza A & Zanamivir & Oseltamivir (Neuraminidase inhibitors) for Influenza A & B. 3) Appropriate antibiotics – only for bacterial pneumonia. Slide79: Prophylaxis – Immunoprophylaxis – Inactivated Influenza A & B virus vaccine produced in eggs. H & N antigens chosen from the types that circulated during the prior season. Indicated for – Age > 65, chronic disease, 2nd or 3rd trimester during influenza season, health care workers, < 18 on aspirin.) 2) Chemoprophylaxis – The therapeutic agents respectively for Influenza A & B. Indicated for – High risk or unimmunized. USDA Slide80: Age Related Mortality at Different Times 1% Did Older People Have Antibody From Related Influenza Virus? Did Young People Have a Cytokine Storm? Slide81: Influenza Risk Ratio of Mortality, Age > 65:< 65 (H1N1) 1918-1919 Pandemic 0.3:1 1928-1929 Epidemic 11:1 (H2N2) 1957-1958 Pandemic 18:1 1967-1968 Epidemic 203:1 (H3N2) 1968-1969 Pandemic 10:1 1980-1981 Epidemic 67:1 Slide82: West Nile Fever & Encephalitis USGS Culex Mosquito CDC ↑Crow Raven→ USGS Slide83: CDC Slide84: FWS NPS Slide86: West Nile Fever – Manifestations Fever Rash (1/3) Chills Malaise Headache Backache Nausea & Vomiting Arthralgia Myalgia Slide87: West Nile Encephalitis – Manifestations: Reduced Level of Consciousness Seizures Flaccid Paralysis with Areflexia Parkinsonian Movements Diagnosis is by antibody study (ELISA). There is no antiviral treatment & no vaccine. Slide88: Hatched are deaths. No mortality at age less than 50*. *Clinical Characteristics of the West Nile Fever Outbreak, Israel, 2000, Chowers, et al, EID, V7, No4, Jul-Aug, 2001 Slide89: CDC EID West Nile Disease in Israel –2000 46% of Cases & 97% of Deaths occurred in the 15% of people aged > 60. Slide90: Conclusions Regarding West Nile Virus: Most infections (80%) are asymptomatic or result in West Nile Fever not West Nile Encephalitis. 2) The geographic range of West Nile Infection is likely to spread. 3) The Elderly have a higher attack rate of West Nile Fever, West Nile Encephalitis, and West Nile Virus related Mortality than do younger adults.