Mosquito Control

  1. Mosquito Safety
  2. What You Can Do
  3. DIY Control
  4. What We Do
  5. Mosquito Spraying 

Some mosquitoes can carry West Nile Virus (WNV). Mosquitoes only need two tablespoons of water to breed, and water can collect just about anywhere. Each year, the City of Mansfield implements its Mosquito Surveillance Testing Program. The main goal of mosquito control is to decrease the number of adult mosquitoes by eliminating breeding grounds wherever possible. Partner with the City to prevent WNV and protect yourself from mosquitoes by staying informed and getting involved in eliminating breeding sites. 

The City is currently at risk level 2

Mosquito Risk 2 - Enhanced risk

Risk Level 1 - Normal Response

  • Condition: Probability of human outbreak is remote.
  • Trigger: Normal mosquito activity with no evidence of virus/disease detected during the past 6 weeks in vectors, humans, or other hosts

The best control methods for Level 1 are promoting  source reduction and personal protection. Conduct standard larviciding approaches. No adulticide spraying will occur at this response level.

Risk Level 2 - Enhanced Response

  • Condition: Low to moderate probability of human outbreak.
  • Trigger: Normal mosquito activity with little or no evidence of virus/disease; trapped mosquitoes test positive for West Nile and indicate that exposure likely occurred locally; enhanced response level is due to the recent historical presence of West Nile in vectors, humans, or other hosts within the vicinity of Mansfield (approximately 10 miles).

The best controls for Level 2 are promoting source reduction and personal protection. Conduct standard larviciding approaches. Increase efforts in areas where positive mosquito pools are detected. Consider adult mosquito control procedures in and around the area of positive sample locations. Response emphasis should remain on larvicide and habitat removal activities, but may include some isolated adult mosquito control procedures to maximize risk reduction for human health.

Risk Level 3 - Public Health Warning

  • Condition: Moderate to high probability of human outbreak.
  • Trigger: Multiple mosquito pools collected at different times and locations test positive for West Nile. Probable human or equine cases reported by laboratory testing.

The best control methods for Level 3 are promoting source reduction and personal protection. Intensify larviciding efforts. Increase efforts in areas where positive mosquito pools were detected if applicable. Once surveillance results determine the presence of West Nile Virus or other mosquito-borne pathogens in multiple pools and/or multiple birds tested in the same vicinity the threat to human health is considered imminent and if larvicides are not reducing the threat to an acceptable level, the Public Works Director, or a designated representative, shall determine the need to consider targeted adult mosquito controls. The decision to spray is based on the effectiveness of spraying adulticides and risks to the health of residents. It is not made on complaints from residents. Spraying efforts should be implemented only in the vicinity (approximately ¼ mile or more) of areas where mosquito traps and bird tests indicate a dense pathogen bearing mosquito population or where positive tests are located near dense human populations.

Risk Level 4 - Public Health Alert

  • Condition: Multiple human cases are confirmed.
  • Trigger: Multiple human cases confirmed by laboratory testing and continued viral mosquito activity.

The best control methods for Level 4 are promoting source reduction and personal protection. Intensify larviciding efforts. Use insect growth regulators in targeted areas to reduce larvae. Once a confirmed positive, human case of West Nile Virus or other mosquito-borne pathogen has been discovered and if larvicides are not reducing the threat to an acceptable level, the Public Works Director, or a designated representative, shall determine the need to consider targeted adult mosquito controls.