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The Hawaii Department of Health is looking for ways to beef up its staffing and expertise for responding to mosquito-borne viruses like dengue and Zika, following a report from the Centers for Disease Control and Prevention pointing out “critical deficiencies” at the agency.
The state currently employs half as many vector control workers as it did seven years ago, before budget cuts reduced the number of workers responsible for key interventions to prevent the spread of diseases like dengue.
Of particular concern to the CDC is the limited number of entomologists at the Department of Health — scientists who study insects and play a vital role in tracking and assessing possible outbreaks.
“Longer term, introductions of other mosquito-borne diseases such as Zika and chikungunya are likely and will require entomologic expertise at the State Department of Health that currently does not exist,” Lyle R. Petersen, director of the CDC’s Division of Vector-Borne Diseases, wrote last month in an assessment of the state’s response to the current dengue fever outbreak.
Petersen’s warnings come at a time of rapidly growing concern about the Zika virus, which is being linked to a rise in serious birth defects in places where the disease is widespread.
The World Health Organization is expected to decide Monday whether Zika constitutes a global health emergency. In the meantime, the CDC has already issued a travel warning advising pregnant women to consider postponing trips to nearly two dozen countries and territories where transmission of the disease is occurring, including Brazil, Mexico, Puerto Rico, Samoa, and most recently the U.S. Virgin Islands.
The current threat of a Zika outbreak in Hawaii is low, medical experts say, in part because the mosquito that poses the biggest risk of transmitting the virus to humans has been eradicated from most islands in the state, and is now only found on portions of the Big Island.
But Hawaii sometimes has an attitude of complacency that’s not productive for getting in front of potential crises, said Dr. Vivek R. Nerurkar, chair of the Department of Tropical Medicine, Medical Microbiology and Pharmacology at the John A. Burns School of Medicine.
“Hawaii has all the ingredients for having an outbreak of dengue, which already happened, or Zika,” Nerurkar said. “The question is just how will it happen and how can we contain it? Currently I think we are doing a good job of controlling it, but we need to also be more proactive.”
Zika is an illness with symptoms similar to dengue, including fever and joint pain. In most instances, the symptoms are mild, but there is mounting evidence that the disease may cause a serious birth defect known as microcephaly.
The disease was discovered in Uganda in the 1940s, and was also previously thought to be in parts of Asia.
“The Zika virus is not supposed to be in the Americas,” said Dr. Isaac Bogoch, a tropical infectious disease specialist at Toronto General Hospital, who was the lead author of a recent study evaluating the potential spread of Zika in the Americas.
Although there have been sporadic Zika outbreaks in the last decade, including one in 2007 on Yap Island in Micronesia, the proliferation of the illness across the Americas in the last year has been alarming.
The link between Zika and microcephaly — a condition where a baby is born with an abnormally small head and brain development issues — has not been proven yet. But the rising number of cases of microcephaly among children born from mothers who had contracted the Zika virus is leading to a crisis-level response from many nations.
There is no vaccine or treatment for the disease. The most dramatic response so far may be in El Salvador, where health officials have started asking women to delay getting pregnant until 2018.
Just like dengue, it is transmitted most commonly by the Aedes aegypti mosquito. The mosquito picks up the virus when it bites an infected person, and spreads it by biting another person.
There is also at least one known instance of the virus being spread through sexual intercourse, Nerurkar said.
“Not a lot is known about the Zika virus,” Bogoch said. “Not a lot is known about how efficiently it is transmitted from mosquito to people. We are learning more and more about it.”
The Department of Health has been sending information to doctors and hospitals in Hawaii with information about how to identify the virus, said Dr. Keith Kawaoka, deputy directory of environmental health.
“I think overall we are very concerned about Zika getting into here and establishing some kind of foothold,” Kawaoka said.
If doctors suspect a case of the Zika virus, they would contact the Department of Health for testing, Kawaoka said.
“From the vector side, all these possible diseases are spread basically the same way, so all the responses we are doing for dengue is also addressing Zika,” Kawaoka said.
Hawaii used to employ 52 vector control workers and four entomologists. Now it has 23 vector workers spread out across the islands, and two entomologists based on Oahu. One of those two entomologists is expected to retire soon, Kawaoka said.
That’s fewer vector control workers than most individual counties in Florida, while cities in East Asia of a similar size to Honolulu would be expected to have dozens if not hundred of vector workers, said Jon Winchester, a preventative medicine scientist for the U.S. Navy who wrote his master’s thesis on the history of mosquitoes in Hawaii.
There are two mosquitos that can carry the dengue virus — and can also transmit other viruses like Zika.
The most recent outbreak of dengue has been confined to Hawaii Island, in part because the mosquito most commonly responsible for spreading the virus has been eradicated from the other islands.
Although efforts were made to rid Hawaii Island of the the Aedes aegypti mosquito, the state was never successful in completely stomping the insects out — in part because federal funding for eradication efforts ran out in the 1960s.
Oahu also received a bigger focus because of the threat to military personnel during World War II.
Aedes albopictus, which is found more commonly on all the islands, can also spread the disease but is much less likely to do so. That’s because albopictus is found more in the wilderness, and feeds on lots of animals besides just humans.
Aedes aegypti, also known as the yellow fever mosquito, is a more aggressive insect that prefers to feed on humans. It is found in urban environments and commonly feeds indoors.
At the same time, the Department of Health’s communications staff has been cut from five people in 2009 to one person today.
Those staff reductions present a real problem because combatting the number of mosquitos and communicating to the public about disease prevention are two of the most effective ways of avoiding a large outbreak.
“Communications capacity is woefully inadequate,” Petersen wrote in the December assessment.
The state has been able to maintain sufficient surveillance and case follow-up in the current dengue outbreak, but its epidemiological resources are taxed, Petersen wrote.
“I am concerned about staff fatigue and a potential crisis if another health event develops,” Petersen wrote, adding that assistance from the CDC would be available as needed.
“While highly skilled expertise resides in the Department of Health, limited surge capacity of technical proficiency exists for public health emergencies such as the dengue outbreak,” Petersen wrote.
The Department of Health is looking for vacant positions in other areas that it might be able to use to temporarily fund additional vector control workers and entomologists, Kawaoka said.
The DOH is also hopeful that recently introduced bills in the Legislature to increase vector staffing in the state will provide more longterm relief.
Gov. David Ige, whose office requested that Petersen assess the state’s response, has seen the report and met with Petersen twice while he was in Hawaii, Communications Director Cindy McMillan said.
“Certainly the (dengue) outbreak has been on his radar, and he’s been monitoring the approach and response to it,” McMillan said.
Though Petersen’s report contained numerous recommendations and calls for urgent action to increase capacity at the Department of Health, he was effusive in his overall praise of the state’s coordinated response to the current dengue outbreak on Hawaii Island.
“The coordination of efforts is one of the best I have witnessed anywhere,” he wrote, adding that the response was well-organized and serves as a model for others.
Not everyone agrees with the CDC’s positive assessment of how Hawaii has handled the current dengue outbreak on the Big Island.
Several lawmakers from affected areas say the response was too slow, and that the state needs to be more proactive moving forward.
Because of the possible risks to pregnant women, even a small outbreak of Zika could kill tourism in Hawaii for a year or two, Rep. Richard Creagan said.
“That could cost the state a billion dollars,” Creagan said. “Putting $10 million or $30 million in right now is probably a good way to go.”
One possible way to better address the problem moving forward would be to create some vector reserve corps — a group of people who were trained and could be hired seasonally or as needed.
“We need the ability to accelerate vector control quickly, and I am not sure the best way to do that,” he said.
There are also several bills being introduced this session that address the issue of vector control and establishing an emergency fund for outbreaks, he said.
Kawaoka said the Department of Health would like to have staffing available at least at the levels they were before the cuts seven years ago.
“With that staffing, I think we can meet those various challenges that are coming in,” Kawaoka said. “We don’t know the size of the potential outbreaks that might be coming to the state, but if the needs are met we think we can meet those challenges.”
Winchester, the Navy scientist who studied the history of mosquitoes in Hawaii, also says the state should be doing more to monitor and eradicate the insects that carry diseases like dengue and Zika.
“it’s kind of short-sighted,” Winchester said. “Preventative medicine is always better than reacting after the fact.”
Part of being proactive will also mean boosting research capabilities in Hawaii, Nerurkar said.
Nerurkar said in 2009 he put in an application with the state Department of Agriculture to import samples of the Zika virus so that the University of Hawaii could begin studying the disease. The application was denied, he said.
“I said eight years ago Zika is not far off,” Nerurkar said. “You don’t need a crystal ball to look at that.”
He expects to put in another application soon.