Chemical or biological control of disease vectors can negatively impact the environment.

Climatic factors affect vector population and breeding. For example, with warmer temperatures vector populations may increase because vectors that are cold-blooded thrive in a warmer environment. Also, meteorological factors affect the incidence, transmission season duration, and spread of vector-borne diseases. In addition to this, human activity can facilitate vector breeding with water storage, mining, deforestation, and poor waste management.

Chemical control can generate pollution and environmental degradation that may intensify environmental health risks and create harmful living conditions for the affected population and any host communities. Pollution of the water, soil, and the air is a threat to human health and wellbeing and exacerbates poverty and inequality. Pollution also affects animals and plants, thus degrading natural ecosystems and their ability to provide essential natural services and resources for society. The economic burden of pollution is usually significant, and the cost of rehabilitation of degraded environments is often prohibitive. Similarly, whilst biological control avoids chemical contamination of the environment, there may be operational limitations and undesired ecological consequences if the impact of the environmental modification is not well defined and the method poorly calibrated. Biological control methods are only effective against the immature stages of vector mosquitoes and are typically restricted to use in large concrete or glazed clay water-storage containers or wells.

Some sections of the community will be more vulnerable to vector-related diseases than others, particularly babies and infants, older people, persons with disabilities, sick people, and pregnant and breastfeeding women. Identify high-risk groups and take specific action to reduce that risk. Take care to prevent stigmatisation.

Eutrophication
Loss of biodiversity and ecosystems
Soil pollution
Air pollution

• Soil, air, and water pollution from some disease control methods, including the use of chemicals.
• Environmental degradation from the use of biological controls.

• Infection prevention methods can sometimes use chemicals, such as pesticides, to reduce the risk of spread and infection. Such prevention measures can affect water sources and soil which can lead to additional health problems.
• Standing water and wastewater are breeding grounds for mosquitoes. Contaminated water can enter watercourses, soil, and surface water, which may be used for drinking, washing, cleaning, and bathing, increasing health risks to users, including women and children. Waterborne zoonotic microorganisms present perhaps the greatest past, present, and future risks to the safety of ambient water and drinking water.

•  Plan the least environmentally damaging methods of control.
• Safe use of hazardous chemicals
• Use of the smallest quantity of chemicals necessary to limit the vector threat, as well as the total body count of vectors killed.
• A Safety Plan should be developed for each chemical control operation.
• Assessment, training, and safe use and storage of substances hazardous to health.

• Implement infection prevention and control (IPC) measures at all levels of healthcare according to risk. Take into account the environmental impacts of such measures, such as pesticides which can contaminate soil and water – use alternative methods when possible.
• Assess disease vectors and plan the least environmentally damaging methods of control. Include an assessment of negative impacts on other beneficial organisms, including plants, insects, and soil biota.
• The chemicals and biological agents used to control vectors are sourced from substances that have a broad and largely indiscriminate impact on the environment to ones that have limited and sometimes very targeted impacts on specific species, or stages of species development. The use of chemicals should be avoided where there are safe viable alternatives. Where chemicals are used, the most up-to-date chemicals or biological agents should be used even if older supplies are available at low or no cost and when possible, the main emphasis should be minimising the use of chemical controls. Where chemical controls have to be applied, provide guidance for their application to minimise undesirable impacts.

Humanitarian actors responding to the global Covid-19 outbreak have reported their most effective actvities being Infection Prevention and Control through hygiene promotion and social distancing

• # of locations where disease vectors are successfully controlled without the use of chemicals that could harm non-disease flora or fauna
• Chemical control operation has a safety plan and Staff and/or community members know how to use it.
• Sensitisation messages on chemical vector control proper use and management are developed and promoted at household and settlement levels

Mitigation of environmental damage

Time and expertise to assess disease vectors and assess alternatives to select the least environmentally damaging, including simple actions such as promoting community behaviour change.

Chemical control operations include a safety plan
IEC material to be developed – The safety plan should be publicly available and used in the training of applicators and other personnel involved in pesticide use operations.