EMILIO DEBESS, DVM, MPH

Transcription

1 EMILIO DEBESS, DVM, MPH OREGON STATE PUBLIC HEALTH VETERINARIAN (971) FINANCIAL ARRANGEMENTS I, nor any members of my family, DO NOT have a financial arrangement related to the content of this CME activity. OBJECTIVES Discuss surveillance and treatment of zoonotic diseases including Lyme disease and West Nile virus Discuss Avian influenza Discuss patient education and prevention of zoonotic diseases

2 Rate per 100, VECTOR-BORNE DISEASES, OREGON Lyme disease Tularemia Malaria West Nile virus LYME DISEASE Lyme disease is caused by the bacterium Borrelia burgdorferi and is transmitted to humans through infected blacklegged tick bites. Typical symptoms include fever headache fatigue a characteristic skin rash called erythema migrans. LYME DISEASE WHAT DO TICKS LOOK LIKE? On the Pacific Coast, western blacklegged ticks (Ixodes pacificus) spread the disease Ticks mostly attach to: groin armpits scalp There are many different kinds of ticks, and they can be found at different stages of growth. Deer Ticks adult adult In most cases, the tick must be attached for hours or more before the Lyme disease bacterium can be transmitted Larvae have 6 legs, and nymphs and adults have 8 legs! 8

3 EARLY DISSEMINATED STAGE (DAYS TO WEEKS POST-TICK BITE) Untreated infections may spread from the site of the bite to other parts of the body, producing an array of symptoms that may come and go, including: Most humans are infected through the bites of immature ticks called nymphs Additional EM lesions in other areas of the body Facial or Bell's palsy (loss of muscle tone on one or both sides of the face) Severe headaches and neck stiffness due to meningitis (inflammation of the spinal cord) Pain and swelling in the large joints (such as knees) Heart palpitations and dizziness due to changes in heartbeat LATE DISSEMINATED STAGE (MONTHS-TO-YEARS POST-TICK BITE) Approximately 60% of patients with untreated infections may begin to have intermittent bouts of arthritis, with severe joint pain and swelling. Large joints are most often affected, particularly the knees. Arthritis caused by Lyme disease manifests differently than other causes of arthritis and must be distinguished from arthralgias (pain, but not swelling, in joints). POST-TREATMENT LYME DISEASE SYNDROME Approximately 10 to 20% of patients treated for Lyme disease with a recommended 2 4 week course of antibiotics will have lingering symptoms of fatigue, pain, or joint and muscle aches. Most medical experts believe that the lingering symptoms are the result of residual damage to tissues and the immune system that occurred during the infection.

4 HUMAN LYME DISEASE INFECTION OREGON, Distribution of Ixodes pacificus in Oregon Heavy line represents approximate limit of range Green circles represent I. Pacificus, not collection sites LYME DISEASE IN OREGON, A STUDY Between , tick exposure occurred: 40% in own backyard 23% while camping 20% while hiking Approximately 60% of those with tick exposure reported EM rash

5 LYME DISEASE IN OREGON, A STUDY Clinical presentation N Percent EM Joint Pain EM and Joint Pain EM, Joint Pain and Neurological Neurological Joint Pain and Neurological Asymptomatic EM and other rash Tick embeded Rash Non- EM Joint Pain/Cardiac Death Relapse LYME DISEASE TREATMENT LYME DISEASE IN OREGON DOGS Patients treated with appropriate antibiotics in the early stages of Lyme disease usually recover rapidly and completely. Antibiotics commonly used for oral treatment include: doxycycline amoxicillin cefuroxime axetil Patients with certain neurological or cardiac forms of illness may require intravenous treatment with drugs such as ceftriaxone or penicillin.

6 60 LYME DISEASE DIAGNOSIS IN DOGS BY YEAR OREGON, Cases IDEXX data only (n=157) LYME DISEASE DIAGNOSIS IN DOGS BY MONTH OREGON, Cases Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec IDEXX data only (n=157)

7 WEST NILE VIRUS: BACKGROUND WEST NILE VIRUS: ENTOMOLOGY First isolated 1937 in Uganda from blood of a febrile woman Family: Flaviviridae Genus: Flavivirus Japanese Encephalitis (JE) Antigenic Complex JE Complex: JE, Murray Valley encephalitis, St. Louis encephalitis, West Nile, Kunjin viruses Transmissible by mosquitoes Causes febrile, and sometimes fatal, human illnesses First ID in the US in 1999 and in Oregon in 2004 Natural infection occurs in over 40 mosquito spp, Mosquito species in Oregon: Mostly Culex: Cx pipiens, Cx trivittatus, Cx restuans, Cx salinarius Many Aedes species : Aedes vexans, Ae triseriatus, Ae japonicus, Other mosquito species: Culiseta melanura, Psorophora ferox, Anopheles punctipennis WEST NILE FEVER: HUMAN INFECTION 80-90% are asymptomatic 10-20% are febrile, influenza-like illness with abrupt onset: Moderate to high fever H/A, sore throat, backache, myalgia, arthralgia, fatigue Rash, lymphadenopathy < 1% develop acute aseptic meningitis/encephalitis (> 50 years old) 1-10% of meningitis / encephalitis cases are fatal

8 WEST NILE VIRUS TRANSMISSION CYCLE Mosquito vector WEST NILE VIRUS SURVEILLANCE West Nile virus Bird reservoir hosts Incidental infections Incidental infections Unique system collects: Denominator & numerator data Human data Non-human animal data: Vertebrate & Invertebrate Multiple databases: Humans Dead birds Mosquitoes Species of veterinary importance Sentinel flocks of chickens Captured wild birds WEST NILE VIRUS (WNV) ACTIVITY REPORTED TO ARBONET, BY STATE, UNITED STATES, 2012 (AS OF OCTOBER 23, 2012)

9 2012 PACIFIC NORTHWEST WNV ACTIVITY 2013 PACIFIC NORTHWEST WNV ACTIVITY WNV Activity by County No Activity Detected WNV Activity by County No Activity Detected Washington WNV Activity Detected Washington WNV Activity Detected Oregon Idaho Oregon Idaho WEST NILE VIRUS ACTIVITY OREGON MAP, COLUMBIA CLATSOP WASHINGTON MULTNOMAH HOOD RIVER SHERMAN MORROW UMATILLA WALLOWA TILLAMOOK YAMHILL CLACKAMAS UNION WASCO GILLIAM POLK MARION LINCOLN LINN BENTON LANE JEFFERSON DESCHUTES WHEELER CROOK GRANT BAKER Year Human Mosquito pools Arboviral activity Dead birds Other animals Sentinel chickens COOS DOUGLAS CURRY JACKSON JOSEPHINE KLAMATH LAKE HARNEY MALHEUR (h) (h) (h) (h) (h) 0 Updated: Sept 19, 2011 h= horse

10 WEST NILE VIRUS: SURVEILLANCE HUMAN SURVEILLANCE DATA AVIAN SURVEILLANCE DATA MOSQUITOES SURVEILLANCE DATA 2013

11 TREATMENT There is no specific treatment for WNV disease; clinical management is supportive. Patients with severe meningeal symptoms often require pain control for headaches and antiemetic therapy and rehydration for associated nausea and vomiting. Patients with encephalitis require close monitoring for the development of elevated intracranial pressure and seizures. Patients with encephalitis or poliomyelitis should be monitored for inability to protect their airway. Acute neuromuscular respiratory failure may develop rapidly and prolonged ventilatory support may be required. PREVENTION INFLUENZA

12 INFLUENZA TRANSMISSION INFLUENZA SYMPTOMS Droplet (3 6 feet) Incubation 1 3 days Fever Headache Myalgia Malaise Duration: 2 7 days Cough Sore throat Occasional GI symptoms INFLUENZA CHANGES IN A MINOR WAY EACH YEAR PERIODIC MAJOR CHANGES drift New strains each year: most people susceptible New vaccine needed each year shift Nobody has immunity Widespread epidemic: pandemic

13 DRIFT AND SHIFT OF H AND N Drift: small changes from RNA mutations Many people are susceptible every few years Vaccines require frequent modification to be effective DRIFT AND SHIFT OF H AND N Shift: major changes Non-human virus infecting humans Reassortment between human and animal strains Pandemic requirement Earthquake fault, New Zealand Health Emergency Management, NZ IMPACT OF INFLUENZA IN A TYPICAL YEAR INFLUENZA MORBIDITY 10% 20% ill U.S.* ~ 225,000 hospitalizations ~ 23,607 deaths Oregon ~ 2,750 hospitalizations ~ 294 deaths *CDC. MMWR 2010; 59:

14 INFLUENZA HOSPITALIZATION RATES BY AGE OREGON EIP, < ILI Rate per 1,000 members INFLUENZA , OUTBREAKS , and , BY FACILITY TYPE Kaiser OREGON, FEB 2011 APR 2012 Kaiser Kaiser Kaiser Respiratory Illness Surveillance Kaiser Permanente Northwest Week of Thanksgiving Week of Christmas (Winter Storm 2008) LTCF/ALF Jail School Other Date ( ) MEDIAN NUMBER OF INFLUENZA AND PNEUMONIA DEATHS BY MONTH OREGON, INFLUENZA VACCINATION 10 0 JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Data source: Oregon Center for Health Statistics, Mortality Data; Based on ICD-10 coded death certificate records- ICD-10 codes J09- J18. P&I mortality based on vital records data underestimates the number of deaths.

15 INFLUENZA VACCINE EFFICACY FLU VACCINE FORMULATIONS 70% 90% among healthy persons <65 years of age 30% 40% among frail, elderly persons 50% 60% in preventing hospitalizations 80% effective in preventing death Shot (into muscle) Any age Fluzone High-Dose: Age 65 years Injection (into skin) Ages years CDC. Epidemiology and Prevention of Vaccine-Preventable Diseases, Spray (into nose; live, weakened virus Ages 2 49 years H5N1 VIROLOGY H5N1 is a virus that occurs mainly in birds, is highly contagious among birds, and can be deadly to them, especially domestic poultry. INFLUENZA (H5N1) Since November 2003, more than 600 sporadic cases of human infection with highly pathogenic avian influenza (HPAI) A (H5N1) virus with high mortality have been reported, primarily by 15 countries in Asia, Africa, the Pacific, Europe and the Near East. (On January 8, 2014, the first case of a human infection with H5N1 in the Americas was reported in Canada.)

16 CANADIAN REPORT Canada has reported the first case of human infection with avian influenza A (H5N1) virus ever detected in the Americas. The case occurred in a traveler who had recently returned from China. H5N1 virus infections are rare and these viruses do not spread easily from person to person. According to Canadian health officials, the patient, who died on January 3, 2014, recently traveled to Beijing, China, where avian influenza A H5N1 is endemic among poultry. H5N1 RISK FACTORS Most Cases of H5N1 in People Have Been Linked to Contact with Infected Poultry Risk factors include visiting a live poultry market and prolonged, unprotected close contact with a sick HPAI H5N1 patient. Seasonality increases during months at the end and beginning of the year. This seasonality corresponds to the seasonality of HPAI H5N1 virus outbreaks among poultry, which increase during the relatively cooler periods. ANTIVIRAL DRUGS CAN BE USED TO TREAT ILLNESS For treatment (and prevention) of human infection with avian influenza A viruses, CDC and WHO currently recommend oseltamivir or zanamivir, two of four prescription antiviral medications currently licensed for use in the United States. In particular, analyses of available HPAI H5N1 viruses circulating worldwide suggest that most viruses are susceptible to oseltamivir and zanamivir. However, some evidence of resistance to oseltamivir has been reported in HPAI H5N1 viruses isolated from some human HPAI H5N1 cases.

17 VACCINE The U.S. Government is Stockpiling H5N1 Vaccine for People in Case Its Needed The United States federal government maintains a stockpile of H5N1 vaccine. The stockpiled vaccine could be used if a H5N1 virus begins transmitting easily from person to person.

18 MERS-COV CASE In April 2012, a 60-year-old male citizen of Bisha, located in southeast Saudi Arabia, became seriously ill with pneumonia. After his condition deteriorated, he was transported to a hospital in Jeddah, where he eventually died. He became the index case of an unknown corona infection, later to be coined Middle East respiratory syndrome coronavirus, or MERS-CoV. MERS-COV MERS-COV The initial suspicion of camels being involved in the event was raised on March 26, 2013, when it became known that a MERS patient from the United Arab Emirates who died in a hospital in Munich, Germany, had been around a sick camel shortly before falling ill. The sick camel was not tested. Recent serosurveillance, undertaken in the dromedary populations of Ethiopia, Nigeria and Tunisia, sampled from 2009 to 2011 discovered a high percentage of the tested animals to be seropositive. Notably, the overall seropositivity was higher in adult animals than in animals younger than 2 years.

19 CLINICAL PRESENTATION A wide clinical spectrum of MERS-CoV infection has been reported ranging from asymptomatic infection to acute upper respiratory illness, and rapidly progressive pneumonitis, respiratory failure, septic shock and multi-organ failure resulting in death. CLINICAL SYMPTOMS AT ADMISSION At hospital admission, common signs and symptoms include: fever, chills/rigors headache non-productive cough dyspnea myalgia Other symptoms can include sore throat, coryza, nausea and vomiting, dizziness, sputum production, diarrhea, vomiting, and abdominal pain. PATIENT UNDER INVESTIGATION PATIENT UNDER INVESTIGATION Fever AND pneumonia or acute respiratory distress syndrome (based on clinical or radiological evidence) AND EITHER: A history of travel from countries in or near the Arabian Peninsula 1 within 14 days before symptom onset, or close contact 2 with a symptomatic traveler who developed fever and acute respiratory illness (not necessarily pneumonia) within 14 days after traveling from countries in or near the Arabian Peninsula 1 or a member of a cluster of patients with severe acute respiratory illness (e.g., fever and pneumonia requiring hospitalization) of unknown etiology in which MERS-CoV is being evaluated, in consultation with state and local health departments, Fever AND symptoms of respiratory illness (not necessarily pneumonia; e.g. cough, shortness of breath) and being in a healthcare facility (as a patient, worker, or visitor) within 14 days before symptom onset in a country or territory in or near the Arabian Peninsula in which recent healthcare-associated cases of MERS have been identified 3.

20 INCUBATION LABORATORY FINDINGS The median incubation period for secondary cases associated with limited human-to-human transmission is approximately 5 days (range 2-13 days). Laboratory findings at admission may include : leukopenia lymphopenia thrombocytopenia elevated lactate dehydrogenase levels PREVENTION TRAVEL PREVENTION TIPS Airborne Infection Isolation Room (AIIR) Gloves Gowns Eye protection (goggles or face shield) Respiratory protection Hand hygiene As a general precaution, visitors to farms, markets, barns or other places where animals are present are advised to practice general hygiene measures, including regular hand-washing before and after touching animals, and avoiding contact with sick animals. The public is warned against the consumption of raw or undercooked animal products, including milk and meat.