Managing pests at the border

Pests that can affect public health are called medical vectors. These pests can spread diseases by carrying viruses, bacteria, or parasites from one host to another.

Medical vectors of potential public health significance include:

• mosquitoes
• rats
• fleas
• lice
• bed bugs
• cockroaches
• ticks
• mites.

Both government agencies and local public health services carry out activities to exclude, detect, and control unwanted pests. Some activities are done by Ministry for Primary Industries (MPI) officers on behalf of Health NZ and others are done by local public health teams.

Key activities include:

• checking risk goods before they leave their country of origin such as inspecting used vehicles
• spraying insecticide that stays active on surfaces of aircraft that fly international routes (residual spraying)
• inspecting ships and yachts arriving at New Zealand ports.
• removing or killing insects (disinsecting) untreated aircraft and checking their high‑risk cargo.

Using approved transitional facilities to inspect and clear high‑risk imported items such as:

• animals and animal products
• food
• plants and plant products
• used machinery and vehicles
• wood and wood products.

Public health services carry out or oversee surveillance around international ports and airports. This includes:

• checking for exotic mosquitoes using larval traps, adult traps, and surveys
• collecting all larvae and mosquitoes and sending them for species identification
• checking for mosquito breeding sites at ports and airports and reporting these so they can be treated to kill the larvae and adults, and/or managed
• reviewing surveillance information for trends and to inform planning and response activities

We use specialised entomologist (insect experts) to identify mosquitoes and provide technical advice on pests of public health significance.

New Zealand biosecureexternal link

Even with strong border controls, pests may still arrive. A fast response helps prevent them from establishing in New Zealand.

Mosquito response

A mosquito response aims to stop exotic mosquitoes from spreading. The response depends on if it is a mosquito:

• detection – a suspected exotic mosquito species
• interception – confirmation of exotic larvae or adults found at the border or linked to recent travellers or imported goods
• incursion – confirmed breeding and establishment of an exotic mosquito in New Zealand, not linked to recent arrivals

Notifications from the public

The public can help by reporting unusual or suspected exotic pests.

Report suspected exotic mosquitoes to Health NZ:

• Phone: 0800 669 943

Report other exotic organisms to MPI:

• Phone: 0800 809 966
• Report a pest or diseaseexternal link - MPI

Key control measures include:

• removing mosquito habitats, especially near ports and airports
• removing standing water, which is where mosquito larvae grow
• treating breeding sites using approved methods such as S‑methoprene.

An integrated pest management (IPM) plan is an environmentally friendly, practical approach to controlling pests. Instead of relying on one method, IPM uses a mix of strategies based on what is found during inspections, monitoring, and reports.

An IPM plan usually includes:

• identifying the pests that need to be controlled
• preventing pests by removing things that attract or support them such as standing water or poorly stored rubbish
• monitoring (such as regularly checking areas where pests could hide or asking crew to report sightings)
• using mechanical controls like traps or window screens
• using pesticides when appropriate such as insect sprays or rat poison.

IPM plans are a key document that vessels making international voyages should have as part of the ship sanitation certification system.

Ships Sanitation Certification system