Media Release

01 August 2005

Exotic Mosquitoes Intercepted at Ports of Auckland

Auckland Regional Public Health staff Service staff are responding to the unexpected finding of exotic mosquitoes at the Ports of Auckland at the weekend.

Ministry of Agriculture and Forestry Quarantine staff captured an exotic adult mosquito, while conducting their routine duties at the Port early on Saturday evening.

An immediate search of the vicinity revealed a number of exotic mosquito larvae on a cargo hatch that had been off loaded from a ship that had arrived in Auckland a few days before the find.

The specimens that were found were Stegomyia aegypti (Yellow Fever Mosquito) and Stegomyia albopictus (Asian Tiger Mosquito). The two species are known to be able to spread of a number of diseases including Yellow Fever, which is one of three quarantinable diseases internationally, Dengue Fever, Dengue Hemorrhagic Fever, and Ross River Virus. The Asian Tiger Mosquito can also spread Japanese Encephalitis and West Nile Virus.

MAF quarantine staff (MQS) took samples for confirmation and treated the immediate site to kill any mosquitoes. MQS reported the incident to the Auckland Regional Public Health Services staff, who are treating habitat and monitoring the area to detect an further mosquitoes.

Deputy Chief Technical Officer from the Ministry of Health JR Gardner says, "The cargo hatch that contained the larvae has been treated and fumigated. The cargo sheds in the area have been fogged to ‘knock down’ any other adults that might be sheltering in them. A survey has been conducted in the vicinity of the finding and any areas where mosquitoes could live and breed has been treated.

"We're confident that these measures have killed any other mosquitoes that might have been (harboring) in the cargo hatches, but the Regional Public Health Service are maintaining close surveillance around the area and are conducting further searches for mosquitoes,” Mr Gardner said.

Health protection staff have placed a number of larval and adult mosquito traps in the vicinity and Ports of Auckland are assisting with the operation.

“The fact that MQS staff detected the adult mosquito and the larvae within a short time has been a major bonus for us. This meant that a rapid response followed and improved the chances of achieving an eradication of this potential hazard. Biosecurity strategy relies greatly on everybody’s participation in keeping our borders secure, in this event the MQS staff, the Port Company and the Public Health Services have worked closely together,” said Mr Gardner.

“It is essential that the site is closely monitored for the next few weeks and it is requested that anyone working in the vicinity of Jellicoe Wharf who notices any mosquito activity such as insect biting or ‘wrigglers in pooled water’ to assist by reporting this to the Public Health Services”. The phone number to ring the Public Health Service is 09 2621855.

Of the two, the Asian Tiger Mosquito would be the greatest challenge to eradicate if it were to become established in New Zealand. This species had demonstrated an ability to live in new areas, adapting well to temperate climates and feeding on humans, domestic and wild mammals and birds. The Yellow Fever Mosquito, on the other hand, feeds only on humans, is climate sensitive, and has a limited flight range.

Health protection staff will monitor the traps in the area for a further three weeks to ensure that the mosquitoes have not escaped into the local environment.

Mr Gardner said the fact that the exotic mosquitoes have been detected at the border shows systems are working efficiently, and it means it is less likely they will spread in New Zealand.

Exotic mosquitoes of public health significance have been intercepted on 40 occasions since January 1998.



Background:

Mosquitoes go through four separate and distinct stages of its life cycle: Egg, Larva, Pupa (resting stage), and Adult.

Exotic mosquitoes of public health significance have been intercepted on 37 previous occasions since January 1998.

Exotic mosquitoes are most likely to enter New Zealand by way of:

• Being lodged in deck cargo on international ships
• Breeding in water storage and open containers on fishing boats and yachts
• Breeding or attached to used tyres
• Breeding in cavities and containers on used vehicles, used machinery and other imported goods.

MAF Quarantine Service staff are the first line of defence in the search for exotic organisms on imported goods. Public health staff carry out routine surveillance for mosquitoes and respond to interceptions of exotic mosquitoes.

Biosecurity agencies ask that cargo handlers and members of the public who note anything unusual on imported goods to "see it, contain it and report it''. This could mean closing off the vehicle, container, package or room, and reporting it to the MAF exotic pest hotline 0800 809 966.