Mosquitoes are thriving as global warming continues with increase temperature and increase precipitation. Make it easier for mosquitos to transmit disease. Most people who got West Nile virus don’t show any symptom, only about 1 out of 5 people will have symptom and1 out of 150 will develop a serious illness. Last, there is not vaccines to prevent or treat West Nile Virus (CDC). Research done by Soverow and his colleagues took WNV reported cases from Centers of Disease Control from 2001 to 2005 and obtained daily data on ambient temperature, dew point temperature, and precipitation from the National Oceanic and Atmospheric Administration (NOAA) National Climatic Data Center to form graphs in order to see the relationship between environment and WNV transmission. They showed temperature are positively associated with the number of reported WNV infection during the same week and in the following 3 weeks, specifically, a 5°C increase in mean maximum weekly temperature was associated with a statistically significant 32–50% higher incidence of reported WNV infection. Also, they showed that one or more days per week of heavy precipitation defined as ? 50 mm in a single day was associated with a 33% higher incidence of reported WNV infection during the same week, and the following 2 weeks. This shows that as climate changes continue, it leads to increase in WNV transmission and an increase population of Culex mosquitos. Moreover, different temperature will either speed up Culex mosquito development or decease it. For Cx. quinquefasciatus, there was a significant decrease in the number of days required for total development from egg to adult between temperatures of 15-27°C but no further significant decrease at 30 and 34°C. In Cx. quinquefasciatus, survival to adult stage was significantly lower at 15 and 34°C than at 20-30°C (Rueda LM, 1900). This concludes Cx. quinquefasciatus have highest growth rate and survival rate between 15-30°C which is 59-86°F and as Earth temperature rising, mosquitoes will rise with it. All these research show that climate changes are helping mosquitoes and diseases they carry to spread faster around the nation.