The Legislature finds and declares all of the following:

(a) Excessive numbers of mosquitoes spread diseases and reduce livestock productivity.

Terms Used In California Health and Safety Code 2100

  • department: means State Department of Health Services. See California Health and Safety Code 20
  • Evidence: Information presented in testimony or in documents that is used to persuade the fact finder (judge or jury) to decide the case for one side or the other.
  • State: means the State of California, unless applied to the different parts of the United States. See California Health and Safety Code 23

(b) From 1972 to 2008, inclusive, the state provided the University of California with funding in order to perform research on mosquitoes and mosquitoborne disease. That funding was absorbed by the University of California in 2008 and almost all state-based mosquito research was eliminated.

(c) Climate change is a likely influence on vectorborne disease spread, including both short-term outbreaks and shifts in long-term disease trends.

(d) The State Department of Public Health notes three vectorborne diseases that climate change may impact in the state: hantavirus, Lyme disease, and West Nile virus. As the ecology of vectors changes with climate, exposure to disease in people may increase significantly.

(e) Mosquitoes are an increasing vector of concern, particularly those species that have been introduced from other countries because changes in temperature and precipitation conditions can allow exotic species to become established in places where they could not previously survive year-round. Once established, the mosquitoes can reproduce in extremely small amounts of water and are very difficult to control. As temperatures rise, mosquito reproductive cycles are shortened, allowing more breeding cycles each season, and viral transmission rates rise sharply. These mosquitoes bite aggressively during the day and can spread a variety of diseases, including chikungunya, yellow fever, and dengue fever.

(f) The World Health Organization has stated that there is much evidence of associations between climate conditions and infectious diseases, noting that mosquitoborne illnesses increase fivefold in the year after an El Niño event, like the weather patterns experienced in California in 2016.

(g) A 2008 study published in the American Journal of Preventive Medicine stated that adapting to the effects of climate change will require the development and enhancement of surveillance systems, adequate response plans, and locally appropriate strategies to control and prevent vectorborne disease.

(h) West Nile virus was first detected in California in 2002 and by 2004 had spread to all 58 counties in the state. This disease can result in debilitating cases of meningitis and encephalitis and death to humans, horses, avian species, and other wildlife.

(i) In August 2007, the Governor determined West Nile virus activity to be an imminent threat and issued an executive order, which included $11.5 million in emergency funding for the State Department of Public Health and local mosquito abatement and vector control districts to identify and treat areas with heavy West Nile virus presence.

(j) In spite of a statewide plan to prevent West Nile virus, in 2015 West Nile virus resulted in 860 human cases and 19 equine cases statewide. There were 53 human and five equine deaths.

(k) Mosquito control agencies, the State Department of Public Health, and the University of California have collaborated on efforts to control mosquitoes and prevent mosquitoborne illnesses. Collectively, mosquito control agencies have financially sustained prevention resources, including the Dead Bird Hotline and sentinel chicken testing, which provide first response lab testing and monitoring when potential avian West Nile virus activity is detected locally. These programs have been successful in tracking infected mosquitoes and preventing humans from acquiring the virus.

(l) In 2011, vectorborne disease specialists first detected the spread of two nonnative, invasive mosquitoes in California, Aedes aegypti and Aedes albopictus. These species are not detectable through the traditional prevention methods employed by the State Department of Public Health, including the testing of diseased birds.

(m) Invasive mosquitoes are extremely effective transmitters of dangerous and potentially deadly diseases, including the Zika virus, which has garnered international alarm. In addition to Zika, these species transmit chikungunya, yellow fever, and dengue fever.

(n) As of January 20, 2017, there were 472 cases of Zika virus reported to the State Department of Public Health that were acquired outside of the state or from contact with a traveler, and four infants have been born with birth complications.

(o) The United States Global Change Research Program recommends that the monitoring of vectorborne diseases in relation to climate change requires coordinated, systematically collected, long-term surveillance datasets to demonstrate how climate change will determine the risk for human exposure to vectorborne diseases.

(p) The Legislature therefore recognizes all of the following:

(1) The threat of West Nile virus, the Zika virus, and other diseases is presenting greater pressure on public health and vector control entities across the state.

(2) The management of these threats will only become more challenging as California’s climate continues to change.

(3) Surveillance, monitoring, and mapping are the most effective ways to control mosquitoes, and the state has no formally recognized program to do so.

(4) The California Vectorborne Disease Surveillance System, known as CalSurv, is managed by the Center for Vector-borne Diseases at the University of California, Davis, and is capable of performing those predictive functions of mosquito control.

(Added by Stats. 2019, Ch. 422, Sec. 1. (AB 320) Effective January 1, 2020.)