“El Niño and Dengue Fever” Workshop at NDPTC’s “Third Thursday” public meeting

Posted on Dec. 17, 2015

University of Hawai’i Manoā campus (December 17, 2016)

Before the holiday season, the National Disaster Preparedness Training Center held a monthly community meeting on “El Niño and Dengue Fever” at the University of Hawaiʻi Manoa campus on December 17, 2015.

 Emcee’d by NDPTC Weather and Climate Program Specialist Thomas Bedard, the meeting’s three speakers were:

Owen Shieh -- NDPTC Weather and Climate Program Manager

Dr. Sarah Y. Park -- State of Hawaiʻi’s Dept. of Public Health Chief of the Disease Outbreak Control Division and State Epidemiologist

Edward Chico Caballero -- Instructor, EMS Programs, Kapiʻolani Community College in Honolulu

Thomas Bedard opened the workshop by describing the latest outbreak of Dengue fever concentrated on the Island of Hawai’i.  (Note: as of January 11, 2016 the total number of confirmed cases since the beginning of the outbreak remains at 210; these cases include 190 residents and 20 visitors.) 

Recently, researchers have explored the linkage between climate change, especially “El Niño”, a prolonged warming in the Pacific Ocean sea surface temperatures when compared with the average value, and infectious disease outbreaks, due to increased mosquito activity.

A certified Meteorologist and former Typhoon Duty Officer at the Joint Typhoon Warning Center (JTWC) at Pearl Harbor, Owen Shieh explained that the El Niño Southern Oscillation is a global cycle every several years in the Pacific Ocean.

“El Niño is not a predictor of weather but an influence that can shift weather patterns,” Owen Shieh said.  “In Hawaiʻi we see the biggest effects in winter with drier weather that persists into the spring.”  He added, “El Niño is not just a weather impact, it can impact health.  Rising temperatures, humidity and additional rainfall contribute to more mosquitoes breeding and possibly spreading more diseases, such as Dengue fever.”

A former CDC Epidemic Intelligence Service Officer in bacterial respiratory diseases, Hawaiʻi’s leading public health epidemiologist Dr. Sarah Y. Park shared her extensive knowledge of the mosquito-borne disease Dengue Fever, a mosquito-borne viral disease occurring in tropical and subtropical areas: symptoms are high fever, rash, and muscle and joint pain.

“Climate change could play some factor in the increase of infectious diseases and dengue, but doesn’t explain it all,” she explained.  “The disease spreading is complicated and requires more modelling and data. Firstly, to understand and contain this disease you need to know about mosquitos.”

She pointed out that two types of mosquitoes exist in Hawaiʻi and both bite people, but only one type is the carrier of Dengue fever: Aedes Aegypti.  This mosquito species shares the same urban environment as people, and stays close to its food supply or blood of mammals, including birds, dogs, and people.

Aegypti has been found in pockets throughout the Island of Hawai’i. It requires either an infected person to come in contact with a mosquito, or an infected mosquito to come in contact with a person. Then the infection cycle continues as infected human blood is transferred to the mosquito and then the mosquito infects other peopled; Dengue fever cannot be spread directly from person to person.

Dr. Sarah Park emphasized that many Dengue fever cases in Hawaiʻi originate from infected human travelers to Hawaiʻi.

“We are concerned about the whole State, not just the Big Island,” she said.

Dr. Park further explained that any mosquito borne disease introduced in a urban setting such as Honolulu, the consequences would be extremely challenging to control by the public health authority.

Dengue fever is rarely life-threatening and the symptoms last approximately a week, hence the disease is not a State government’s highest priority for public health emergency response.  Of far greater danger are other mosquito borne diseases such as Chikungunya, which has severe and disabling symptoms that may last for weeks or even months.

In order to analyze the disease spread, Dr. Park highlighted the need for quick laboratory identification for Dengue fever.  Since no commercial laboratory exists in Hawaiʻi that tests for Dengue fever, the Hawaiʻi State Health Department is responsible for Dengue fever testing and the public is notified immediately of any outbreaks.

In terms of tips, Dr. Park said to not leave any standing water outside homes in buckets or flower pots, since mosquitos can breed in the small pool of water, even in the heel of a slipper. 

The last speaker, Edward Chico Caballero, an experienced EMS instructor and paramedic, gave some advice on Dengue fever prevention, including wearing long-sleeve shirts and to bathe in DEET, a standard mosquito repellant – and simply, not to be bitten by mosquitoes by avoiding activities in areas of high mosquito concentration during the early morning and late afternoon periods when mosquito activity is greatest. 

He also advised that the symptoms for Dengue fever are the same as many other common diseases, such as influenza and gastroenteritis. Therefore self-diagnosis can sometimes lead to frantic calls that can tie up emergency medical resources, such as 911 and ambulances. Severe forms of Dengue fever will leave patients severely dehydrated, unable to stand and/or they become “puffy” and their blood pressure may drop dramatically. If you experience these symptoms, then it is time to call for an ambulance.  Throughout the State, isolation ambulances are available for transportation of suspected carriers of severe infectious diseases to a medical facility.

As a final community workshop wrap-up by NDPTC’s Executive Director, Dr. Karl Kim, he said: "With evidence that we are experiencing the strongest El Niño on record and one of the largest outbreaks of dengue in Hawaiʻi, it is of critical importance that we work collectively to raise awareness and increase preparedness as well as response capabilities to the effects, hazards and threats to our communities in Hawaiʻi. This is an important part of the work we do at the NDPTC, a national center on natural hazards preparedness training funded by FEMA and at the University of Hawaiʻi."