No ‘high risk’ areas remain

Hawaii Island’s dengue fever outbreak is showing signs of slowing.

Hawaii Island’s dengue fever outbreak is showing signs of slowing.

Laboratory confirmations of dengue cases have been slowing since late January, and the latest infection risk map posted on the state Department of Health’s website shows no areas of “high risk” on the island — a first since state health officials initially began providing outbreak data to the public in early November in conjunction with the launch of its “Fight the Bite” campaign, aimed at preventing contact between humans and mosquitoes, which carry the dengue virus.

As of Friday afternoon, the Big Island’s confirmed case count stood at 260, with no new dengue infections being identified since mid-February.

Hawaii County Civil Defense Administrator Darryl Oliveira said he remained “cautiously optimistic” about the trend, pointing to the fact that the infection potential map is based solely on the number of cases of dengue fever that have been reported to health officials. Many people experience symptoms but never visit a doctor, get their blood tested, or report the illness.

“With any outbreak … there’s always a degree of under reporting. Throughout this outbreak, it’s been shared by epidemiologists that on average the under-reporting average is about 10 percent,” he said. “And we’re hearing anecdotally that people have been sick and didn’t report, didn’t go in, didn’t get checked, for various reasons, including frustration with trying to get access to get tested.

“Also, there have been comments made that people didn’t feel there was a need to go get checked because there’s no cure or treatment, and the symptoms for some of them weren’t so bad that they didn’t just want to ride it out.

“So, for a variety of reasons, we want to say we’re cautiously optimistic, but at the same time, considering that there could be cases that haven’t come forward, we’d like a significant amount of time to feel that the risk has been minimized.”

State Epidemiologist Dr. Sarah Park agreed that the latest data is encouraging, but stressed that “we have to continue to monitor for cases and work together across the state to prevent mosquito activity to help protect our community.”

“We cannot afford to let up our guard,” she added.

While the numbers of positive confirmations of dengue have dropped, people are continuing to be tested for dengue at a fairly steady rate, Oliveira said.

“One of the questions I had of our state lab, was whether we weren’t seeing a false indication of a promising outlook because they have seen dropoff of (the amount of testing). But they are consistently running specimens at the same level,” he said.

The last few months, the lab has been completing an average of about 450 tests on blood specimens per month, and that number appears to be holding. The lab reported completing 20 specimen tests on Friday alone.

Oliveira added that the Department of Health has been seeing a gradual increase of influenza cases recently, which might be leading some people to be tested for dengue when they feel the accompanying aches and pains of the flu.

On March 1, Civil Defense reopened Hookena Beach Park, which was closed to the public on Nov. 4, shortly after cases of locally acquired dengue were first confirmed on the island.

Milolii Beach Park and Waipio Valley both remain closed, until sufficient time has passed without new cases in those areas, Oliveira said.

The Milolii area’s most recent onset of dengue fever took place on Jan. 20, while the most recent case in Waipio was Feb. 1.

“We are constantly monitoring the situation in those two areas to hopefully get to the point where the risk potential is low enough we can open them,” he said.

However, at a Monday meeting with the Waipio Valley community, Civil Defense heard of some people in the valley who might be sick with dengue but have not reported their illnesses, Oliveira said.

“We are trying to verify that,” he said.

He stressed that while the recent trend looks promising, Hawaii Island residents should continue to avoid contact with mosquitoes and to report illnesses to their health care providers and to the state Department of Health.

“The important message is, this isn’t over,” he said. “People need to continue what they’re doing.”

Concern about dengue infections on the island remain high, as evidenced last week by the cancellation of blood drives that were scheduled to be held in West Hawaii.

Shortly before the risk potential for Kailua-Kona was changed Tuesday from high to moderate by the Department of Health, the Blood Bank of Hawaii announced it had canceled scheduled drives at LDS Kona, Mauna Kea Beach and Konawaena High School because of the high risk potential in the Kona area.

The blood bank increased its capacity at other drives on Oahu to make up a resulting 238-pint deficit in its collections.

Email Colin M. Stewart at cstewart@hawaiitribune-herald.com.