HILO — Consider it a passing grade with room for improvement.
In its first assessment of the Big Island’s dengue fever outbreak, the U.S. Centers for Disease Control and Prevention said the public health response has been adequate, but it also noted concerns with mosquito control efforts and staffing levels at the state Department of Health.
In response, state and county officials say they are expanding mosquito spraying in neighborhoods with confirmed cases and may bring in additional assistance from other departments.
“We feel this assessment is more than just an assessment,” said Keith Kawaoka, deputy director for environmental health. “We view it as a map to guide us moving forward.”
The outbreak from the mosquito-borne disease, which appears to be the largest in the United States since World War II, has reached 153 cases.
DOH released the report, requested by county Civil Defense and state officials, Tuesday.
Lyle Petersen, who heads the CDC’s vector-borne disease division, conducted the assessment while visiting the island earlier this month.
He noted Hawaii County Civil Defense has implemented an effective incident command structure but “critical deficiencies” remain with DOH in the areas of communications and medical entomology. Staff fatigue could become an issue, Petersen said.
“The epidemiological response has been timely and well considered,” he wrote. “However, current resources are taxed, and there is limited surge capacity if another significant health event arises in the state.”
That is hampering efforts to conduct assessments on mosquito habitats and the effectiveness of control measures, Petersen said.
Kawaoka said the CDC has provided some of its own entomologists to help with the dengue response, but they will leave later this week. Additional support could come from other state departments, he said.
“If we need additional support, we will certainly request it,” Kawaoka said.
Petersen recommended that more needs to be done to control mosquito populations, noting that field reports suggest only 25 percent of homes within 200 yards of a confirmed case are surveyed. That’s lower than the target participation rate of 90 percent.
He also recommended that state and county workers switch from soapy water to larvacide when targeting mosquito breeding areas. Insecticides are also being used to target adult mosquitoes.
“Current efforts to reduce mosquito breeding sites may be insufficient to reduce mosquito populations enough to impact transmission because soapy water as a larvacide may be ineffective and it has proven difficult to achieve the 200-yard radius of control,” Petersen said.
Kawaoka said use of larvacides are being reviewed.
He said the size of survey areas will be expanded, though that can be limited if a property owner doesn’t provide consent. Spraying near confirmed cases will also be increased from two or three times every three to four weeks to twice a week.
Petersen also noted concern over fatigue among vector control workers. Kawaoka said other county and state workers are being trained and can be used if needed.
“We’ve got reserves,” he said. “I think capacity-wise, we are doing all right.”
Darryl Oliveira, county Civil Defense administrator, said he made the request for the assessment and welcomed its results.
One area that he wants to see expanded is public education, he said, adding that engagement from residents is crucial to fighting the disease. That also includes allowing state and county workers on private property to survey and spray for mosquitoes.
“If anyone from the public comes home and finds a note or informational packet left, please call,” Oliveira said.
Email Tom Callis at tcallis@hawaiitribune-herald.com.
