Health Alert: U.S. Embassy La Paz, Bolivia

Location:  Santa Cruz, Bolivia

Events: Santa Cruz declared a ‘departmental emergency’ on January 8th due to dengue fever.  While Cochabamba has not yet followed suit, emergency rooms in the tropical region of the department have reported a dramatic increase in the number of cases.


Dengue fever is a tropical viral disease that is spread by the bite of a female Aedes aegypti mosquito.  She has an almost imperceptible bite, preferring to come from behind and bite ankles and elbows.  She often bites several people to complete a single blood meal, which is necessary for her eggs to develop.  She usually feeds during the hours around dusk and dawn but may bite at any time during the day – especially indoors, in shady areas, or when the weather is cloudy.  In order to transmit the dengue virus through her bite, the mosquito must have bitten someone who had the virus and survive the incubation period of 8 – 12 days.  The life span of an adult mosquito is only about three weeks, so this is not easily done.  The Aedes’ flight range is limited (100 meters), so you are more likely to get dengue from a mosquito bite at the grocery store than from one at an isolated house; for a mosquito who has access to a large number of people is more likely to have bitten someone who is sick with the virus.  She lays her eggs about three days after feeding on blood, in a natural or artificial water-holding container, preferably one located in the shade.  Adult offspring will emerge from the water in as little as 7 – 8 days.  An area with standing fresh water is more likely to have a sizeable mosquito population.

The only way to prevent dengue is by avoiding mosquito bites.  Although there is a new dengue vaccine on the market (Dengvaxia), it is not recommended by MED for various reasons.

To Avoid Mosquito Bites

  • Wear long sleeve shirts, long pants, socks and shoes when mosquitoes are most active.
  • Apply repellents such as DEET, picaridin, oil of lemon eucalyptus or IR3535 only to exposed skin and/or clothing (as directed on the product label). Do not use repellents under clothing.
  • Use mosquito netting over infant carriers, cribs and strollers.
  • Keep your doors and unscreened windows closed tightly

Dengue Fever

Approximately 87% of dengue victims have few or no symptoms.  The symptoms of classic dengue are as follows:

  • Fever/chills: 39 – 41°C (102 – 105°F)
  • Starts 3 –14 days after bite
  • Usually lasts less than 7 days
  • Headache, pain behind the eyes
  • Muscle pain, especially in the lower back
  • Bone pain (earning the nickname “break-bone fever”)
  • Pink/red blanching rash on trunk 2 – 4 days after onset of fever
  • Petechiae (non-blanching red dots)
  • Nausea, occasionally vomiting

Dengue fever can be diagnosed with a blood test.  If you suspect that you might have dengue fever following a visit to a lower altitude, please contact a health center.

Treatment is symptomatic: FLUIDS, FLUIDS, FLUIDS, rest and Tylenol.  Avoid taking aspirin and non-steroidal anti-inflammatory medications like ibuprofen and naprosyn because they can worsen hemorrhagic symptoms.

People with more severe illness can develop hemorrhagic dengue and will require hospitalization and IV fluids.

Worrisome Signs of Possible Hemorrhagic Dengue:

  • Abdominal pain – intense and sustained
  • Persistent vomiting
  • Abrupt change from fever to low body temperature
  • Restlessness or severe sleepiness