Hantavirus and More 1 2/21/2014 Objectives Hantavirus Plague - PDF document

2/21/2014 Emerging and Re-emerging infections from the North American Wild Sukhjit S. Takhar, MD Brigham and Women ’ s Hospital Harvard Medical School Hantavirus and More 1

2/21/2014 Objectives • Hantavirus • Plague • Rocky Mountain Spotted Fever • Rabies Would you rather have? • Hantavirus • Plague • Rocky Mountain Spotted Fever • Rabies 2

2/21/2014 48 year old male 3 days of influenza-like symptoms Shortness of breath Back country hiking and camping 7 days ago in Yosemite Hantavirus Pulmonary Syndrome Sin Nombre virus 3

2/21/2014 Hantavirus • Severe hemorrhagic fever with renal syndrome • Hantavirus pulmonary syndrome Hantavirus in Yosemite 4

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2/21/2014 Hantavirus in the US • 1993 – 24 patients with severe pneumonia – 75% case fatality rate 6

2/21/2014 Hantavirus • Parasites of rodents and insectivores • Reservoir of Hantavirus (SNV): Deer Mouse – Cotton and rice rats (south east) Transmission • Breath air contaminated with virus – Rodent urine – Rodent droppings – (contaminated food, bites, etc…) • Incubation period: 1 to 6 weeks • HPS does not have person to person transmission 7

2/21/2014 Clinical Case Definition • Febrile illness with interstitial edema (ARDS) in a previously healthy individual – Fever, headaches, muscle aches – Pulmonary edema Clinical Manifestations 1. Fevers, chills, myalgia, headaches 2. Pulmonary vascular permeability 3. Shock 8

2/21/2014 Laboratory Abnormalities • Hemo-concentration • Leukocytosis – Bandemia – Atypical lymphocytes • Thrombocytopenia Diagnosis • Rural rodent exposure? – Influenza like illness? – Shortness of breath? 9

2/21/2014 Treatment • Supportive care • Antibiotics until confirmatory testing • Analgesics and antipyretics Could it be? • Zoonosis from rats? – Plague? • Tick Borne? – Tularemia? • Infectious pneumonia • Sepsis 10

2/21/2014 Plague Yersinia pestis 11

2/21/2014 History of Plague • Black death • Late Middle Ages ~1347-1350 – 75 million – 200 million deaths – Killed 1/3 of the human population 12

2/21/2014 Pathogenesis • An Infection of Rodents and Fleas – Fleas feed on bacteremic hosts (often a rodent) – Feed on other rodents and transmit the disease Transmission • Bite from an infected flea (or rarely other animals) • Direct contact with contaminated tissues • Rarely, inhalation of respiratory section • Short Incubation (1-6 days) 13

2/21/2014 Clinical Manifestations • Bubonic Plague • Septicemic Plague • Pneumonic Plague Oregon case 14

2/21/2014 Bubonic Plague • Fevers, chills, weakness • Regional Lymphadenitis (Buboes) • Often the first stage of the disease Treatment • Fatal cases are associated with delays in diagnosis and treatment – Aminoglyocoside – Fluoroquinolones – Tetracyclines 15

2/21/2014 Plague • Report to state health department • Consider bioterrorism • Antibiotic prophylaxis Plague in Yosemite 16

2/21/2014 Could it be? • Anthrax? • Tularemia? 17

2/21/2014 Rocky Mountain Spotted Fever Rickettsia rickettsii Rocky Mountain Spotted Fever • Vector: Hard Ticks (dog ticks) • Incubation period (2 – 14 days) • Untreated mortality: 20-87% • Needs to be attached for at least 4-6 hours 18

2/21/2014 Rocky Mountain Spotted Fever • North Carolina • Oklahoma • Arkansas • Tennessee • Missouri 19

2/21/2014 Risk Factors • Exposure to the tick vector – Exposure to dogs – Wooded area – Peaks in summer months Clinical Presentation “ A febrile disease, characterized clinically by a continuous moderately high fever, and a profuse or purpuric eruption in the skin, first appearing on the ankles, wrists, and forehead, but rapidly spreading to all parts of body. ” 20

2/21/2014 RMSF • Clinical Triad: Fever, Rash, and Headache is only present 3% early in disease • Consider the disease with fever and headache • Rash appears 2-5 days after onset of fever • Innoculation eschar is rare Diagnosis • History • Physical Examination • Epidemiological Data • Then laboratory confirmation 21

2/21/2014 Tick Removal • Fine-tipped tweezers to grasp tick • Pull upward • Clean wound • Do not use nail polish, petroleum jelly, or heat Treatment • Treated Mortality 5% • Tetracyclines and Chloramphenicol – Doxycycline in Children is ok for this! 22

2/21/2014 Other things to think about… • Meningiococcemia • Tick Borne Rickettsial disease – Anaplasmosis – Erlichiosis • Other Tick Borne Diseases – Tularemia? 23

2/21/2014 Rabies Rhabdovirdae Rabies • Epidemiology of human rabies reflects local animal rabies • Developing countries: Dogs • United States: Bats and rabid wild animals 24

2/21/2014 Rabies • Neurotropic viral infection transmitted from a bite of an infected animal • Travels to CNS • Acute, progressive encephalomyleitis • Incubation 1-3 months (days – years) • Highest case fatality ratio of any infectious disease if untreated Rabies • 92% of reported cases of rabies in 2010 were in wild animals • Wild carnivores and Bats – Racoons 36.5% – Skunks 23.5% – Bats 23.2% – Foxes 7.2% 25

2/21/2014 Rabies • Bites, scratches, or mucous membrane exposures to bat • Clustering of human cases with bat exposures have never been reported Wound Management • Clean the wound – Soapy water – Betadine • Protective effect of wound care may be as important as vaccination 26

2/21/2014 Postexposure Prophylaxis • Rabies Immunogloblin (RIG) + Rabies Vaccination • 2010 CDC Guidelines – Reduced (4-dose) regimen – Improved from the Semple Vaccine • (Daily injections of 5-10 ml) into abdominal wall) Rabies • Survival from clinical rabies is extremely rare • Consider rabies in patients with progressive encephalitis • Avoid wildlife • Prompt PEP 27

2/21/2014 Selected References • Rhee, D. K., Clark, R. P., Blair, R. J., Katz, J. T., & Loscalzo, J. (2012). Breathtaking Journey. New England Journal of Medicine , 367 (5), 452-457. • Hantavirus, C. D. C. (2012). Atlanta, GA: US Department of Health and Human Services, CDC; 2012. • Perry, Robert D., and Jacqueline D. Fetherston. "Yersinia pestis--etiologic agent of plague." Clinical microbiology reviews 10.1 (1997): 35-66. • Chapman, Alice S., et al. "Diagnosis and management of tickborne rickettsial diseases: Rocky Mountain spotted fever, ehrlichioses, and anaplasmosis--United States: a practical guide for physicians and other health-care and public health professionals." MMWR. Recommendations and reports: Morbidity and mortality weekly report. Recommendations and reports/Centers for Disease Control 55.RR-4 (2006): 1. • Dantas-Torres, Filipe. "Rocky Mountain spotted fever." The Lancet infectious diseases 7.11 (2007): 724-732. • Shah, Usha, et al. "Trial of human diploid cell rabies vaccine in human volunteers." British medical journal 1.6016 (1976): 997-997. • Willoughby Jr, Rodney E., et al. "Survival after treatment of rabies with induction of coma." New England Journal of Medicine 352.24 (2005): 2508-2514. • Rupprecht, Charles E., and Robert V. Gibbons. "Prophylaxis against rabies." New England Journal of Medicine 351.25 (2004): 2626-2635. 28