Infectious Disease in Mesa County

1. Infectious Disease in Mesa County • Plague • West Nile Virus • Colorado Tick Fever • Hantavirus

2. Plague • Bacteria: Yersinia pestis • Flea bite (78%),Direct animal contact (20%), Aerosolized animal Urine/Feces (2%) • Human cases • April-November (93%) • Increased activity of fleas and hosts

3. Types • Bubonic Plague= 80-90% of cases • Signs:Fever, malaise, chills, headache, “Bubos” and possibly vomiting, abdominalpain, nausea, petechiae • Septicemic Plague- Systemic spread • Signs:Similar to bubonic, plus Prostration, circulatory collapse, septic shock, organ failure, hemorrhage, Necrosis of extremities, Microthrombi blocking capillaries • Pneumonic Plague • Incubation: 1-6 days • Primary - Y. pestisinhaled • Secondary - septicemic form spreads • Signs: Fever, chills, headache, septicemia Respiratory distress, hemoptysis • Person-to-person possible

4. With early treatment – Survival ~100% Supportive treatment Antibiotics treatment Aminoglycosides Streptomycin, kanamycin Doxycycline, tetracycline, chloramphenicol Penicillins and cephalosporins are NOT effective Don’t handle dead animals Report animal die-offs Rodent-proof home Use insect repellent Treat pets for fleas Treat rodent sites Take pet to vet if symptoms develop Redness or swelling around mouth See a health care provider if human symptoms develop Treatment Prevention

6. The West Nile Virus • Flavivirus-avirus, NOT a bacteria. Antibiotics are ineffective. • Infectshumans, birds, mosquitoes, horses and other mammals • Ecology & Transmission • Culex species(43 species) of mosquito is cause of human cases. • Isolated number of cases from ticks • Human Disease: • Incubation: 3-14 days • 80% asymptomatic or mild flu-like illness • 20% develop sudden fever, weakness, headache, myalgia, nausea, vomiting • Symptoms last 3-6 days in mild cases • Severe illness develops in less than 1% (1:150) infected with the neurological component- Encephalitis (meningoencephalitis)

7. Incidental hosts Humans, horses, and other animals Amplifying hosts Birds Vectors Culex sp., Aedes sp., Ochlerotatussp.

8. Eliminating larval habitats Tires, bird baths, containers, rain gutters, unused swimming pools Avoid mosquito habitats during dawn and dusk when they are most active Adjust watering times and sprinkler heads to prevent water pooling Reduce time outdoors Especially evening hours Wear long pants and sleeves Use mosquito repellent 30% DEET, Picaridin, or Oil of Lemon Eucalyptus Do not use DEET on your animals- check with a vet. Make sure all window screens are intact Use yellow “bug” light bulbs in outdoor light fixtures Prevention Protection

9. Mosquito Control • Mesa County Health Department • Larviciding outside of district boundaries • FREE larvicide samples for home use • Grand River Mosquito Control District • Expanded control area • Increased staff and budget • City of Grand Junction • Treating catch basins • Treating ponds and drainage areas

10. Colorado Tick Fever • Most common tick-borne disease in Colorado • Caused by virus • Maintained in rodent-tick cycle • Transmitted by bite of infected tick • Attached for several hours to transmit enough virus to cause illness

11. Fever Headache Body aches Nausea Abdominal pain Lethargy Currently no treatment Treat symptoms Recovery will take 2-3 weeks Not life threatening Infection produces life-long immunity Symptoms Treatment

12. Hantaviruses • A “viral hemorrhagic fever” • Hantavirus Pulmonary Syndrome (HPS) • Hemorrhagic Fever with Renal Syndrome (HFRS) • Recent Cases: • Four Corners Outbreak • May 2003: Montana, 3 cases

13. Deer Mouse • Peromyscus maniculatus L.L. Masters • Cotton Rat • Sigmodon hispidus • House Mouse • Mus musculus

14. Transmission of Hantaviruses Chronically infected rodent Horizontal transmission of infection between same species by contact Virus is present in aerosolized excreta, particularly urine Secondary aerosols, mucous membrane contact, and skin breaches are also a consideration

15. Signs • Incubation period 14-17 days • Early stage: Fatigue, fever, myalgia, headache and lasts 3-5 days • Later stage 4 to 10 days after initial signs: • Coughing and shortness of breath • Rapidly progressive, non-cardiogenic pulmonary edema and severe hypotension • Hospitalization and ventilation required usually within 24 hours • Patients can recover with early supportive care

16. Prevention • Limit exposure to mouse excrement • Control rodents indoors • Control rodents outdoors • Use safety precautions when cleaning rodent infested areas • Minimize your exposure when enjoying outdoor activities • Prevent access to food sources • Keep food preparation and cooking areas clean • Cover pet and human food overnight • Store garbage in tightly covered or elevated container • Rodent trapping

17. Internet Resources • CDC All About Hantavirus • www.cdc.gov/ncidod/diseases/hanta/hps/noframes/phys/clinical.htm • CDC Infectious Disease Pathology Activity • www.cdc.gov/ncidod/diseases/hanta/hps/noframes/printgenlsection.htm • CDC - Plague information • www.bt.cdc.gov/agent/plague/index.asp • CDC - Division of Vector-borne Infectious Diseases • www.cdc.gov/ncidod/dvbid/index.htm • Mesa County Health Department Website • http://health.mesacounty.us/