Sunset over Haleta – the image of a tropical paradise belies the burden of malaria borne by the Solomon Islands and other parts of the South-West Pacific.

The Anopheles farauti mosquito transmits malaria in the Solomon Islands. This study catches the mosquitoes, dusts them with fluorescent powder, and releases them so they can be distinguished if they are collected on a subsequent night. This can provide vital information about the behaviours and feed-and-breed cycle of the mosquito, allowing for the design of more effective control strategies or interventions for the disease.

Just over 14% of Haleta’s residents will test positive for malaria, giving this part of the world one of the highest malaria infection rates outside of Africa and making life a challenge for locals like young Kati.

The researchers travel each day by boat from their base and accommodation in Tulagi to their study site at Haleta, on Ngella Sule in the Solomon Islands.

The village of Haleta on Ngella Sule in the Solomons is the field site for ongoing studies funded by the Malaria Transmission Consortium and the International Centres for Excellence in Malaria Research.

Neil Lobo, the scientific director of the Malaria Transmission Consortium, dips for mosquito larvae in Haleta’s swamp, quantifying them by genus and by how many exist at each stage of larval development.

Haleta provides what researchers call an “ideal microcosm” of a malarial mosquito’s world: a swamp in which to breed, a village in which to feed, and an oceanic barrier preventing them from flying too far.

On some days, after school, a group of children might arrive by canoe from another village for a soccer match – here, Patson (lower left) concedes the ball to Henry.

Haleta’s children play in the ocean at the end of the day. This village, of 428 people, has a school, a church, a soccer field – and a single water tap for all its residents.

On the boat-trip between Tulagi and Haleta, the jungle is photo-book lush. Among this rich and diverse landscape, researchers are engaged in the study of insects that measure just 10mm long.

In Tulagi, where the team stays during each field trip, sceintist Neil Lobo analyses mosquitoes caught the previous night. Samples are screened to identify the species of mosquito, what animal it had fed on, its age and whether it has mated.

The Tulagi offices of the Solomon Islands’ Vector-Borne Disease Control Program. Their projects include distribution of insecticide-treated bednets, which are less effective against local mosquitoes that bite earlier in the evening, when people are out of bed and out of doors.

As dusk falls, the team prepares for the night’s collections to begin. Behind their hut (centre) is the village swamp, where the local malaria mosquitoes are known to breed.

Each night, a team of local collectors disperses around the village from this hut to catch and collect every mosquito that lands on them in a six-hour period, and bring them back here to the research team.

An Anopheles mosquito caught earlier in the evening waits, dusted with fluorescent powder, and ready to be released. These experiments indicate there can be as little as two days between these mosquitoes seeking the blood-meals they need to lay their eggs.

Weng Chow (left) and Tanya Russell (right) analyse mosquitoes brought in during one evening’s collections; their fluorescent blue light reveals any trace of the powder applied to insects caught and released on earlier nights during these mark-release-recapture experiments.

The children of Haleta, like Clemence, often rope the researchers into their games, or trail them as they go about their tasks.