West Nile Virus California’s Risk Presented by: Amanda Billings Hello, my name is Amanda Billings and I am a MPH student at Walden University. My presentation will include a general overview of West Nile Virus followed by a review of the West Nile Virus statistics in California and the relationship between these statistics and the increased number of neglected pools, hot tubs, and ornamental ponds, as a result of the current trend in foreclosed homes. West Nile Virus Presented by: Amanda Billings

intended audience and purpose The intended audience is California residents To educate California residents on the transmission, health risks and prevention of West Nile Virus (WNV) An ongoing concern in California is the number of foreclosed homes with pools, a potential breeding ground for WNV carrying mosquitoes This presentation is intended for the adult population residing in California neighborhoods. The purpose is to educate California residents on West Nile Virus, including what it is, who is at risk, how it is transmitted, the symptoms of an infection and how this disease can be prevented. Furthermore, education will be provided to California residents regarding neglegted pools as sources of breeding grounds for mosquito vectors of West Nile Virus.

Learning outcomes What WNV is and History Who is at Risk Transmission Symptoms Prevention California Statistics Impact of Neglected Pools Who to Call to Report Dead Birds and Abandoned Pools At the conclusion of this presentation one should be able to describe what WNV is and the history of its arrival in America. Furthermore, those at risk for contracting the virus and the route of transmission; what the symptoms of the virus are and how to prevent the spread of the virus will be presented. Finally, an understanding of the statistics of West Nile Virus in California and the relationship between these statistics and the increased number of neglected pools in this state. In addition, the audience will know who to contact to report dead birds and neglected areas of water.

West Nile Virus What & When Flavivirus Closely related to St. Louis encephalitis virus found in United States First isolated from febrile adult woman in West Nile District of Uganda in 1937 Appeared in North America in 1999 First appeared in California in July 2003 Cx. Tarsalis El Centro, Imperial County Reisen,W., Lothrop, H., Chiles, R., Madon, M., Cossen, C., Woods, L., Husted, S., et al. (2004). West Nile Virus in California. Emerging Infectious Diseases, 10(8). Retrieved July 15, 2009 from http://www.cdc.gov/ncidod/eid/vol10no8/04-0077.htm West Nile Virus is a flavivirus commonly found in Africa, West Asia and the middle East. Other known flaviviruses are dengue virus, Tick-borne Encephalitis Virus, and Yellow Fever Virus. West Nile Virus is closely related to the St. Louis encephalitis virus which is found in the United States. In 1937 West Nile Virus was first isolated from a febrile adult woman in West Nile District of Uganda. It wasn’t until 1999 that the virus first appeared in North America (New York City); California witnessed its first infection of WNV in the Cx tarsalis mosquito in July 2003 in El Centro, Ca (Imperial County).

Who is at Risk? All California Residents Over 50 years of age- Greater Risk Immunocompromised- Questionable Risk All California residents are at risk for contracting West Nile Virus, however those individuals who are 50 year of age and older are at a higher risk of contracting the severe form of West Nile Virus. Those individuals who are immuno-commpromised have not been determined to be at any higher risk for contracting West Nile Virus than immuno-competent individuals.

Transmission West Nile Virus Mosquito Vector West Nile Virus Incidental Infection West Nile Virus is transmitted to the human through the bite of an infected mosquito. The mosquito becomes infected when they feed on an infected bird. The virus then becomes resident in the mosquito’s salivary glands, thus during latter blood feeds the mosquito can inject the virus into humans or animals where it can multiply and cause illness. West Nile Virus has also been reported to be contracted through transplanted organs and blood transfusions. These additional routes were identified during the 2002 West Nile epidemic; during this time there was also one reported case of transplacental transmission, and one reported case through breast-milk. Bird Reservoir Host Incidental Infection CDC. (2006). Transmission of West Nile Virus. Retrieved July 15, 2009 from http://www.cdc.gov/ncidod/dvbid/westnile/qa/transmission.htm

Symptoms Asymptomatic West Nile Fever Severe West Nile Disease 4 out of 5 people West Nile Fever ~20% people infected Fever, headache, tiredness, and body aches, occasional skin rash and swollen lymph nodes Severe West Nile Disease 1 in 150 people infected West Nile encephalitis; West Nile poliomyelitis CDC. (2006). Symptoms of West Nile Virus. Retrieved July 15, 2009 from http://www.cdc.gov/ncidod/dvbid/westnile/qa/symptoms.htm When an individual is infected with the West Nile Virus it is unknown whether or not associated symptoms will be present. The incubation period from the date of infection until symptoms appear is anywhere from 2 to 15 days. 4 out of 5 people will be asymptomatic. In approximately 20% of those infected West Nile fever will develop. The symptoms of West Nile fever are fever, headache, tiredness, body aches, occasional skin rashes and swollen lymph nodes. Severe West Nile disease includes West Nile encephalitis or West Nile poliomyelitis. Approximately less than 1% or 1 in 150 people infected will develop the severe disease. Symptoms resulting from infection can last only a few days to several weeks, however in those with severe disease the neurological effects may be permanent.

prevention Protection from Mosquito Bites Reduce Number of Mosquitoes Vector Management Programs CDC. (2006). Prevention of West Nile Virus. Retrieved July 15, 2009 from http://www.cdc.gov/ncidod/dvbid/westnile/qa/prevention.htm There are several preventative measures that can be taken to protect ourselves and others from West Nile Virus. First protection against mosquito bites can be achieved through the application of an insect repellent to exposed skin and clothing. When choosing an insect repellent choose one that will last the duration you are outside; the higher the percentage of the active ingredient the longer the protection will last. When weather permits wear long sleeves and pants, place mosquito nets over infants in strollers or carriers who are outside, replace or repair broken window and door screens, and stay in the house at dawn and dusk. The second way to prevent transmission of West Nile Virus is by reducing the number of mosquitoes. This can be accomplished by reducing the number of mosquito breeding areas. Examples of potential breeding areas are swimming pools, clogged rain gutters, buckets, old tires etc. The CDC recommends that at least once or twice a week, empty water from flower pots, birdbaths, swimming pool covers, etc, check for clogged rain gutters and clean them out, remove discarded tires, and any other items that could collect water, and be sure to check for areas that may collect waster in places hard to see. Thirdly, vector management programs are essential to prevent outbreaks of West Nile Virus. Vector Management programs are responsible for surveillance for West Nile virus activity in mosquito vectors, birds, horses, other animals, and humans. With the increased number of foreclosures with abandoned pools, the California vector control program has made a call to action; they have asked for the communities help in reporting green pools so that they can be identified and treated appropriately and timely.

California Statistics This map shows the current West Nile Virus activity in California. As of July 16 2009 there has been 169 dead bird positive for the virus, 168 mosquitoes, 10 sentinel chickens positive and 1 squirrel. The counties shaded in green have current West Nile Virus activity , but no human cases. Currently this year in California there are no reported human cases. CDPH West Nile Virus. (2009). Latest West Nile Virus Activity in California. Retrieved July 17, 2009 from http://westnile.ca.gov/

California statistics cont. This graph illustrates the West Nile Virus trend in California for the past four years. In 2006 California had a steep decrease in the number of West Nile Virus infections in mosquitoes, dead birds and humans. However in 2007 and 2008 there was an increase in the number of cases again. This increase in infections was contrary to the evidence based knowledge that there should have been a continuing decrease in the numbers. CDPH West Nile Virus. (2009). Latest West Nile Virus Activity in California. Retrieved July 17, 2009 from http://westnile.ca.gov/

Impact of Neglected Pools Study conducted in Kern County, CA (2007) Findings 205%-280% increase WNV cases since 2004 Unanticipated increase based on weather conditions Decreased key bird species Cx. pipiens quinquefasciatus infection incidence increased (18.5 females/ 1000 mosquitoes) one month earlier than previous year Reisen, W., Takahashi, R.M., Carroll, B.D., Quirimg, R. (2008). Delinquent Mortgages, Neglected Swimming Pools, and West Nile Virus, California. Emerging Infectious Disease, 14(11), Retrieved July 15, 2009 from http://www.cdc.gov/eid/content/14/11/1747.htm A study conducted in Kern County California in 2007 found a 205-280% increase in West Nile Virus cases since 2004. These findings were unanticipated based on the weather conditions and the decrease in the key bird species. The winter and spring weather was 40% the expected rainfall and the temperatures ranged 0.5°C -2.0°C above 30-year normal values. The mosquito population Cx. Tarsalis remained below the 5-year averages because of the decreased rainfall, snowpack, and water allotments to agriculture. In 2007 the overall catch of free-ranging birds in 2007 was 31% of the catch at the same traps during 2006. However, even though these condition existed the study found an increase in the infection incidence of the Cx. Pipiens quinquefasciatus mosquito one month earlier than the previous year.

Impact of Neglected Pools Aerial Survey 17% of 42 visible pools and Jacuzzis appeared green and likely producing mosquitoes In 2008 unmaintained pools previously positive for Cx. p. quinquefasciatus were now occupied by Cx. tarsalis, , a more competent vector of WNV February-August 2008; 31 neglected pools produced 8,978 emerging adult mosquitoes 59% Cx. tarsalis, 41% Cx. p. quinquefasciatus Reisen, W., Takahashi, R.M., Carroll, B.D., Quirimg, R. (2008). Delinquent Mortgages, Neglected Swimming Pools, and West Nile Virus, California. Emerging Infectious Disease, 14(11), Retrieved July 15, 2009 from http://www.cdc.gov/eid/content/14/11/1747.htp So why with the dry weather and decrease number of mosquitoes and birds did the study find an increase in the West Nile Virus cases since 2004? In Kern County, CA there was a 300% increase in notice of home delinquency compared to the spring quarters of 2006-2007. Thus, these home abandonments most likely contributed to the increasing number of neglected swimming pools, hot tubs and ornamental ponds. The study conducted an aerial study of a Bakersfield, CA this aerial shot reveled that 17% of 42 visible pools and Jacuzzis appeared green and were likely producing mosquitoes. The study also found that in 2008 unmaintained pools previously positive for Cx. P. quinquefasciatus were now occupied by Cx. Tarsalis, which is a more competent vector for West Nile Virus. In February-August 2008 31 neglected pools were found to produce 8,978 emerging adult mosquitoes; of this number 59% were Cx. Tarsalis and 41% Cx. P. quinquefasciatus. The conclusion is that the increase in foreclosed homes with abandoned pools in California is responsible for the increase in the West Nile Virus infections seen in 2007 and 2008.

Impact of Neglected Pools This is the aerial shoot taken of Bakersfield, Ca; the red arrows identify green pools; possible breeding grounds for mosquitoes. Aerial photograph of a representative Bakersfield, California, neighborhood taken during August 2007. Red arrows indicate neglected or green swimming pools. Reisen, W., Takahashi, R.M., Carroll, B.D., Quirimg, R. (2008). Delinquent Mortgages, Neglected Swimming Pools, and West Nile Virus, California. Emerging Infectious Disease, 14(11), Retrieved July 15, 2009 from http://www.cdc.gov/eid/content/14/11/1747.htp

Who to Contact State and Local Government West Nile Virus Web Sites http://www.cdc.gov/ncidod/dvbid/westnile/city_states.htm http://westnile.ca.gov/ Vector Control locator http://westnile.ca.gov/ziplocator.php So who do you contact if you should see a dead bird or green pool in your neighborhood ? You can go to your state West Nile Virus website. The first website listed on the slide will take you to the CDC, and provide you with a map, there you can click on any state and it will direct you to the state’s West Nile Virus website. The California website is the second one listed on the screen. Once you go to that website you can click on report a dead bird or squirrel and it will provide you with form to submit online, once the form is submitted you will be contacted for more information. If there is a green or stagnant pool, Jacuzzi, or ornamental pond you can report them to your local vector control program. The website provided here will allow you to enter your zip code and will give you your local program address and phone numbers. Through community participation we can have a better chance of reducing and/or preventing future West Nile Virus infections and potential outbreaks.

Additional Resources CDC West Nile Virus Website http://www.cdc.gov/ncidod/dvbid/westnile/index.htm Mosquito and Vector Control Association of California http://www.mvcac.org/ California Department of Pesticide Regulation. Fight the Bite. http://www.cdpr.ca.gov/docs/dept/factshts/repellents.pdf I have provided you with additional resources and encourage you to review the additional information regarding West Nile Virus, the mosquito and Vector Control Association and how to fight being bitten by a mosquito and what pesticides should be used for best protection.

Reduce Mosquitoes, Clean the Green Do Your Part and Report Although the majority of those infected with West Nile Virus will show no symptoms, it is important for us to be knowledgeable of its existence. In California, we saw a dramatic drop in infections in 2006 however in 2007 and 2008 there was an increase again, this illustrates the importance of being aware of this disease and how we can prevent it. Foreclosures are still happening in California , thus the number of abandoned pools will continue to increase and the possibility of increasing infections will continue to be a current issue. It is important for us as a community to play a role in the prevention of this disease by reporting to the proper officials dead birds, squirrels, neglected pools, hot tubs, and ornamental ponds. I would like to thank you for your time and attention and if there are any questions I would be happy to answer them at this time. Questions?