Exotic mosquitoes found at Ports of Auckland

The Asian tiger mosquito makes the top 100 list of the world's worst invasive species.

Two species of exotic mosquitoes known to carry deadly diseases, including yellow fever, have been discovered at Ports of Auckland.

Ministry of Agriculture and Forestry quarantine staff captured an exotic adult mosquito, during a routine inspection at the port early on Saturday night.

An immediate search revealed a number of exotic mosquito larvae on a cargo hatch that had been offloaded 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 a number of diseases including yellow fever, which is one of three quarantinable diseases internationally, dengue Fever, dengue haemorrhagic fever, and ross river virus. The asian tiger mosquito can also spread Japanese encephalitis and west nile virus.

MAF quarantine staff took samples for confirmation and treated the immediate site to kill any mosquitoes.

The Health Ministry's deputy chief technical officer, John Gardner, said the cargo hatch that contained the larvae had been treated and fumigated.

"The cargo sheds in the area have been fogged to knock down any other adults (mosquitoes) that might be sheltering in them," he said.

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 (harbouring) 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 the fact quarantine staff had detected the adult mosquito and larvae within a short time, and the speed of the response, showed the system was working.

"This ... improved the chances of achieving an eradication of this potential hazard."

The cargo ship had just travelled the southwest Pacific route, passing through Fiji, the Wallis Islands and Futuna.

Mr Gardner said anyone working in the vicinity of Jellicoe Wharf who noticed any mosquito activity such as insect biting or "wrigglers in pooled water" should report this to public health services by phoning 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.

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

- NZPA