A series of powerful earthquakes off the Solomon Islands sparked panic in evacuation centres filled with victims of an earlier flood but apparently caused no serious damage, aid workers said Monday.

A 7.6-magnitude quake woke residents in the flood-hit capital Honiara early Sunday, followed soon after by a 5.9-magnitude aftershock, then a tremor close to midnight that measured 7.5, according to the US Geological Survey.

The quakes prompted two tsunami alerts that were swiftly cancelled and the Solomon Islands government did not report any damage.

However, authorities in Papua New Guinea reportedly said there was one death in a separate 7.1 quake that hit on Friday.

About 9,000 people remain homeless in Honiara after floods earlier this month that claimed at least 21 lives. Save the Children's emergencies manager Graham Kenna said the quakes sent many running for their lives.

"It's terrified the people who are in these displaced centres, they're very, very frightened," he told AFP.

"Most of them went for higher ground but then they rushed back because they wanted to ensure what few possessions they have were safe.

"It hasn't disrupted the work we're doing that much, but it's put the people more and more on edge."

Kenna said food and supplies were being distributed but aid agencies estimated that only 40 percent of the items needed to cope with the disaster had so far arrived in the Solomons.

With regional stockpiles still depleted after Super Typhoon Haiyan battered the Philippines in November, Hanna said additional supplies were being sent from the Middle East and South Asia but could be weeks away.

In the meantime, he said preventing an outbreak of dengue fever, a mosquito-borne disease already common in the Solomons before the floods, was a priority.

"All the extra water that's around is going to make the mosquitoes breed like crazy and I'd say that when it dries out, probably in the next three or four days, dengue's going to be a major issue," he said.

New Zealand said it was sending two health teams, each consisting of 10 medical and support staff, to help the overstretched hospital system in Honiara.

Officials in Wellington, who have already sent two planeloads of aid to the stricken city, said military engineers were also being dispatched to build a temporary bridge over the Matanikau river, which burst its banks in the flooding on April 3.

Australia said it was sending two doctors to join the New Zealand-led medical teams, part of a Aus$3.0 million ($2.8 milllion) response from Canberra that has included mosquito spraying, hygiene kits, water containers, tarpaulins and blankets.

While the Solomons appeared to have escaped relatively unscathed from Sunday's quakes, PNG's National newspaper reported that a young girl was killed when 13 homes collapsed on the island of Bougainville.

It said reports from the remote area were sketchy and authorities were still trying to determine the scale of the damage.

The Solomons and PNG are part of the "Ring of Fire", a zone of tectonic activity around the Pacific that is subject to frequent earthquakes and volcanic eruptions.