5377 Data Mining PowerPoint by Allison Griest

1. How common is West Nile Virus and when is it a threat to equines? By Allison Griest

2. How common is West Nile Virus and when is it a threat to equines? Horses are used both professionally and recreationally. If West Nile Virus is a threat to horses’ existence, humans as the horse owners have a responsibility to protect horses from the virus, no matter where they live. This presentation is catered toward horse owners in Texas North East Independent School District. http://www.neisd.net/elmlang/images/j0189633.jpg. Viewed 02/21/10.

4. West Nile Virus is transmitted through the bite of infected mosquitoes.

5. Mosquitoes become infected when they feed on infected birds.

7. The virus has also been found in Africa, western Asia, the Middle East, and the Mediterranean regions of Europe.Mosquito-pictures.com. http://www.mosquito-pictures.com/mosquito_pictures.htm. 02/24/10.

10. Horse-to-horse transmission of the virus is unlikely because horses do not have significant amounts of the virus circulating in their blood.

11. Clinical signs of a WNV infection include but are not limited to:

12. Muscle twitching

13. Tremors

14. Difficulty rising

15. Convulsions

16. Partial paralysis

17. A droopy lip

19. Notice the deep red states on the 2002 maps. States colored deep red have 800 or more reported cases of WNV.2009 2002 United States Department of Agriculture – Animal and Plant Health Inspection Service. http://www.aphis.usda.gov/vs/nahss/equine/wnv/wnv_distribution_maps.htm. 02/22/10. United States Department of Agriculture – Animal and Plant Health Inspection Service. http://www.aphis.usda.gov/vs/nahss/equine/wnv/wnv_distribution_maps.htm. 02/22/10.

21. However, when WNV appeared in New York in 1999, it didn’t take long for it to quickly spread throughout the Continental United States.

24. Washington had the most cases, with 72. Horses are often traded over the Canadian border. Another data mining question might investigate the reason why Washington has so many WNV cases.2009 United States Department of Agriculture – Animal and Plant Health Inspection Service. http://www.aphis.usda.gov/vs/nahss/equine/wnv/wnv_distribution_maps.htm. 02/22/10.

26. Note the second column in the graph: West Nile Virus Cases.

27. The majority of the cases in Texas appear to occur in the fall months.United States Department of Agriculture – Animal and Plant Health Inspection Service. http://nsu.aphis.usda.gov/nahss_web/arbovirus_county_level.faces?STATE=TX. 02/22/10.

28. Equine WNV Cases in Texas in 2009 This Excel file shows the total of West Nile Virus cases reported in Texas in 2009 and includes the month of earliest detection of the virus.

30. 50% of WNV cases occurred in the month of October.

31. 94% of WNV cases occurred in the fall months of August, September, and October.

33. However, many horses travel across several states for breeding, showing, and trading purposes, so it is also important to know the months that an equine is at the most risk of being bitten by an infected mosquito throughout the Continental United States.

35. The site was most recently updated December 9, 2009. http://nsu.aphis.usda.gov/nahss_web/arbovirus_summary.faces

36. Only 36 states have reported data.United States Department of Agriculture – Animal and Plant Health Inspection Service. http://nsu.aphis.usda.gov/nahss_web/arbovirus_county_level.faces?STATE=TX. 02/22/10.

38. For reference, here is a screen shot of the cumulative number of equine cases for Alabama.

39. As noted previously in this presentation, the second column is of interest.

40. Each chart lists the date of earliest detection of WNV in a county.United States Department of Agriculture – Animal and Plant Health Inspection Service. http://nsu.aphis.usda.gov/nahss_web/arbovirus_county_level.faces?STATE=TX. 02/22/10.

42. The chart does not give a total per month, so first I had to log the data by visiting each state’s spreadsheet.

43. Because of the chance of human error, I could total the number of cases I had logged in the monthly columns and compare it to the chart showing all state information. That chart includes a total number of cases per state for the selected year.United States Department of Agriculture – Animal and Plant Health Inspection Service. http://nsu.aphis.usda.gov/nahss_web/arbovirus_county_level.faces?STATE=TX. 02/22/10.

45. I took the information shown in the chart for Alabama and placed it in an Excel spreadsheet to show how many cases were reported each month.United States Department of Agriculture – Animal and Plant Health Inspection Service. http://nsu.aphis.usda.gov/nahss_web/arbovirus_county_level.faces?STATE=TX. 02/22/10.

47. The additional columns show the number of Eastern Equine Encephalitis (EEE) cases and Western Equine Encephalitis (WEE) cases.

48. There are common equine vaccinations for both of these viruses, but the vaccines and viruses are unrelated to West Nile Virus. Vaccinations against EEE and WEE provide no protection against West Nile Virus.

51. There were a total of 241 reported cases of WNV in 2009. This total was not on the website but was instead discovered through data mining.

53. The majority of cases were reported in August. August’s 89 cases account for 37% of WNV cases in 2009.

55. It can be difficult to isolate your horse from mosquitoes, but there are protective measures.

56. The best ways to keep horses from getting WNV is to:

57. Reduce the source (eliminate mosquitoes)

58. Avoid the source (mosquitoes)

59. Vaccinate against the virusU.S. Department of Agriculture- Animal and Plant Health Inspection Service. http://www.aphis.usda.gov/vs/nahss/equine/wnv/ada_wnv_2007.pdf. Viewed 2/24/10.

61. Remove any potential sources of standing water

62. Clean water troughs

63. Clean clogged roof gutters

64. Turn over wheel barrows that are not in use

65. Manage property with landscaping to eliminate low spots where standing water might collect.Polyjumps.com. http://www.polyjumps.com/acatalog/TWtop.jpg. 02/26/10

67. The risk of exposure to an infected mosquito and the fact that mosquitoes carry the virus make it difficult to predict what regions of the country are most likely to have infected mosquitoes.

68. The AAEP recommends annual revaccination in the spring, prior to the peak WNV season.

69. This supports my finding that the fall months are the months with the most WNV cases, meaning horses are at the most risk for WNV infection during these months.U.S. Department of Agriculture – Animal and Plant Health Inspection Service. http://www.aphis.usda.gov/vs/nahss/equine/wnv/ada_wnv_2007.pdf. Viewed 2/24/10.

71. http://www.dshs.state.tx.us/idcu/disease/arboviral/westnile/statistics//annual/default.asp

72. The annual summaries include the number of cases and counties related to bird, human (virus and fever), mosquito, horse, and other West Nile Virus infections.Texas Department of State Health Services. http://www.dshs.state.tx.us/idcu/disease/arboviral/westnile/statistics//annual/default.asp. 02/25/10.

74. The maps of the United States shown at the beginning of this presentation showed that the number of WNV cases in equines has decreased. However, mosquitoes are the main factor in equine WNV cases.

75. Therefore, the information on the Texas Department of State Health Service’s website will allow me to see if WNV has decreased among mosquitoes.

77. Please note that the dates decrease in order along the x-axis. (The graph starts at 2009, the most recent year.)

81. It will be interesting to see if the number of mosquito cases continues to increase in 2010.

83. This question has two sections.

84. How common is West Nile Virus?

85. West Nile Virus is common enough that the American Association of Equine Practitioners recommends that all horses in North America receive an annual vaccination.

87. West Nile Virus is definitely a threat to equines.

88. The American Association of Equine Practitioners states that the mortality rate for horses with signs of a West Nile Virus infection is 33%.

89. The data shown in my graphs shows that West Nile Virus is most frequent in the fall months, so it is extremely important that horses are vaccinated prior to those months, ideally in the spring.

91. References United States Department of Agriculture – Animal and Plant Health Inspection Service (n.d.). Retrieved February 22, 2010, from http://www.aphis.usda.gov/vs/nahss/equine/wnv/wnv_distribution_maps.htm. United States Department of Agriculture – Animal and Plant Health Inspection Service (n.d.). Retrieved February 24, 2010, from http://www.aphis.usda.gov/vs/nahss/equine/wnv/ada_wnv_2007.pdf.