Public Health activates dengue response plan; identifies 82 homes within 200-meter radius of confirmed case

Aedes albopictus is a small, dark mosquito with a white dorsal stripe and banded legs (Photo from CDC)
  • Dengue viruses are spread to people through the bites of infected Aedes species mosquitoes (Ae. aegypti or Ae. albopictus);
  • These mosquitoes typically lay eggs near standing water in containers that hold water (buckets, bowls, animal dishes, flower pots, and vases);
  • These mosquitoes prefer to bite people, and live both indoors and outdoors;
  • Mosquitoes that spread dengue bite during the day and night;
  • Mosquitoes become infected when they bite a person infected with the virus. Infected mosquitoes can then spread the virus to other people through bites.

    – From the Centers for Disease Control and Prevention

The Department of Public Health and Social Services (DPHSS) has identified 82 homes within the 200-meter radius of the residence of the individual infected with dengue.

According to Public Health, the residents will be asked to have their homes sprayed with insecticide to control adult and larval mosquitoes.

Outreach efforts for the participation of the residents are also underway with the assistance of the Mangilao Mayor’s Office.

Meanwhile, the Guam Department of Education also cancelled classes at Agueda I. Johnston Middle School (AIJMS) and Ordot Chalan Pago Elementary School (OCPES) on Monday, September 16, 2019.

A local contractor will continue spraying insecticide at the two schools, according to a release. The process started Sunday as part of DPHSS’ efforts to prevent local transmission of dengue.

“We want to provide ample time for our school administrators to complete the work to be done at our campuses, and also to also provide all relevant information to faculty, students, and families,” GDOE Superintendent Jon Fernandez said. “We hope our stakeholders will understand as we work to provide information in a thorough manner and allay any concerns.”

Unless otherwise announced, GDOE said classes will continue as regularly scheduled at both schools on Tuesday, September 17.

Response plan

According to Public Health, an alert physician reported the suspect case of dengue fever in a patient with no travel history outside Guam on Tuesday, which was confirmed by its laboratory the following day.

DPHSS said it is the same type of dengue that caused outbreaks in Yap, Palau, Marshall Islands, and the Philippines.

Following, confirmation of the local dengue case, Public Health Director Linda DeNorcey said the department immediately activated its Arboviral Disease Response Plan which includes establishing a command post and enhancing surveillance for dengue fever.

DeNorcey also wants to do vector control by fumigating areas that have a risk for mosquito transmission.

“We are also updating our dengue case management. We are going to do a massive education for patients and the community to present breeding grounds of the mosquito,” DeNorcey said.

Meanwhile, according to territorial epidemiologist Ann Pobutsky, while dengue viruses are spread through the bites of infected Aedes aegypti mosquitoes, it has been eradicated on Guam after World War II following a dengue outbreak.

Pobutsky said the ecological niche was filled by another potential vector carrying mosquito called the Asia Tiger mosquito or the Aedes albopictus.

According to DPHSS, this is the first locally acquired dengue case detected and reported on Guam in the last 75 years as all previous cases were imported from off-island.

DPHSS said it is working closely with the U.S. Centers for Disease Control and Prevention and other partners to minimize the spread of dengue virus. All healthcare providers are urged to be on alert for additional cases, and a physicians’ alert has been disseminated.


DPHSS asks residents to do their part to reduce the mosquito population with some simple steps:

  • Properly cover or dispose all containers that collect rainwater or water, such as flower pots, garbage cans, recycling containers, wheelbarrows, aluminum cans, boat tarps, old tires, and buckets.
  • Flush birdbaths and wading pools weekly.
  • Flush ornamental bromeliads with water, or treat with BTI, a biological larvicide available at most home stores.
  • Clean roof gutters, which can become clogged and hold water.
  • Change the water in outdoor pet dishes regularly.
  • Keep pools and spas chlorinated and filtered.
  • Stock ornamental ponds with mosquito-eating fish.
  • Cover rain barrels with screening.
  • Check for standing water under houses, near plumbing drains, under air conditioner drip areas, around septic tanks, and water pumps.
  • Take steps to eliminate standing water, improve drainage, and prevent future puddling.

It’s important for residents to remember the four D’s of mosquito prevention:

  1. Drain:  Empty out water containers and scrub the sides to remove mosquito eggs at least once every 5 days.
  2. Dress:  Wear long sleeves, long pants, and light-colored, loose-fitting clothing.
  3. Defend:  Properly apply an approved mosquito repellent such as DEET, Picaridin, IR3535, or Oil of Lemon-Eucalyptus.
  4. Dusk and Dawn:  Avoid activity during those times when mosquitoes are most active.