April 20, 2006

Dengue Emerging Infectious Disease Update

 

 

 

Dengue continues to hold its position as an infectious disease with wide reaching effects in tropical and subtropical areas across the globe. The month of March, 2006 saw cases of dengue in Mexico, Paraguay, Ecuador, the Philippines, Malaysia, Saudi Arabia, Madagascar, Maldives, Bolivia, the French Islands, Indonesia, Argentina, Brazil and Venezuela.

 

MEXICO: A case of fatal dengue hemorrhagic fever was confirmed on March 23 in Nuevo Leon [1]. The victim, a 15 year old girl from the Linares community is the first victim of this disease since 1999. The Nuevo Leon sub-secretary for disease prevention and control, Ricardo Huerta-Gallaga, blames this year’s increased rate of dengue fever on low winter 2005 populations of mosquitoes. Vector extermination was not used as it had been previously. During this year, it is estimated that 3,000 people will be infected with the disease.

 

PARAGUAY: On March 26, two cases of dengue were confirmed in a 26-year-old woman in Asuncion and an 11-year-old boy in Itaugu [1].  Factors such as warm weather, rainfall, virus circulation in neighboring Brazil and ubiquitous water collecting sites in metropolitan areas create the risk for a dengue outbreak. While community preventative measures involving the elimination of water collecting sites are needed to prevent an outbreak, they are usually not used.

 

10 cases have been confirmed in Loma Pyta and 7 cases in La Encarnacion. [6].

 

ECUADOR: The Guayaquil, Guayas province saw 5 confirmed cases of dengue hemorrhagic fever [1]. There have been 57 cases of dengue hemorrhagic fever with four deaths this year alone. Many Ecuadorians are at risk of developing dengue hemorrhagic fever because of previous exposure to classic dengue fever [5].

 

PHILIPPINES: In the city of Zamboanga there were 9 cases of dengue. A 3-year old from Sitio Luyahan, Barangay Pasonanca died from the disease [1]. A citywide clean up by residents, involving the destruction of mosquito breeding grounds, is expected to take place in Zamboanga in April.

 

MALAYSIA: From the beginning of the year until March 12, 304 cases of dengue have been reported [2]. The victims, ages 7-52 years old, are from 13 housing estates and villages from 5 districts in Kedah. The State Health Committee chairman, Datuk Saravanan, needs neighborhood organizations to cooperate in eliminating mosquito breeding grounds.

 

In Malacca, there were 10 cases of dengue in the last month [2]. The Malacca city council and Health Department have started a mobile dengue awareness campaign, however it has not been well received.

 

From February 26 to March 5, there were 58 cases of dengue in Penang [4]. That is a 93% increase in cases from the week before when there were only 30 reported cases in the state. The Health Ministry Parliamentary Secretary, Datuk Lee Kah Choon, says the situation is no need for alarm, as these numbers are apparently normal for the area. According to health Committee chairman, Datuk V. Saravanan, mosquito fogging has been conducted in 2 dengue hotspots in Alor Star, where dengue hemorrhagic fever cases have been on the rise since February.

SAUDI ARABIA: Jeddah is battling an outbreak of dengue, where 400 cases have been reported [2]. The Council of Ministers has approved 378 million (USD) on projects to tackle mosquito-borne disease. Culture and Information Minister Iyad Madani said programs to combat dengue include filling in areas with stagnant water, health awareness campaigns, aerial spraying, and refurbish rainwater canals. A three-year insect surveillance program will begin soon.

 

MADAGASCAR (SAINTE-MARIE): The eastern island of Sainte-Marie is battling an outbreak of dengue fever [2]. A medic on the island said medical services could not cope with the number of victims, with 30-50 people being sent the island’s only hospital every day. The island does not have the resources to fight the outbreak.

 

MALDIVES: From January to March 5, 2006, there were 602 cases of dengue fever, with 64 cases of dengue hemorrhagic fever and 9 cases of dengue shock syndrome [2]. Aedes aegypti is the presumed vector in the Maldives, biting during the day and resting and feeding mainly indoors. The Communication for Behavioral Impact (COMBI) Approach is seen as a strategy to promote mosquito control through the mobilization of communities. The COMBI approach works by encouraging populations to practice dengue control and prevention actions through communication, behavioral-change theories and health education [3].

 

BOLIVIA: During the week of March 2, 12 cases of classic dengue fever were reported in Santa Cruz and 2 cases were reported in La Paz [4]. From January to March, there have been 86 cases of dengue [6].

 

FRANCE (ST. MARTIN): The French side of St. Martin is facing an outbreak of classic dengue fever [5]. Stanley Hanson, the head of the Health Department, says the outbreak is manageable, with 2-3 cases reported a week. Currently, DSDS is managing the situation by spraying aircraft coming into St. Martin, as well as recommending the elimination of mosquito breeding sites.

 

FRANCE (REUNION ISLAND): Dengue was detected, along with Chikungunya virus, in 15 patients on Reunion Island [5]. Both viruses are transmitted by the mosquito species Aedes albopictus. The last epidemic on the island, involving several hundred people, occurred in 2004.

 

INDONESIA: Dengue is on the rise in the Bekasi region of Indonesia [6]. From January to March, there were 924 cases of dengue in Bekasi, with 8 deaths. Due to the alarming level of infections, the Bekasi Municipal Administration has allocated funds to dengue prevention (30,000 USD).

 

In Jakarta, the cases of dengue are also increasing [6]. In the greater Jakarta area there were 2470 cases of dengue in January, 2433 cases in February and 2718 cases in March.

 

ARGENTINA: In Puerto Iguazu, there were 3 reported confirmed cases [6]. The Public Health Ministry is performing environmental control actions.

 

BRAZIL: 2 cases of dengue were confirmed in Penapolis, with a total number of 3 since January [6].

 

VENEZUELA:  During the epidemiological week of Mar 5-Mar 11, there were 665 cases of dengue fever [6]. 38 of those cases were dengue hemorrhagic fever. There have been 8277 total cases since the beginning of the year.

 

VIETNAM:  In the southern localities of the Mekong delta region, including Ho Chi Minh City, there was a 20% increase in a year-on-year comparison.  This substantial increase before the peak rainy season is due to environmental sanitary conditions.  The total number of confirmed cases during the 1st quarter of the year stands at over 8,000 with 4 confirmed fatalities.

 

TAIWAN:  The Taiwanese Centers for Disease Control has reported that the incidence of imported dengue fever has risen 60% in a year-on-year comparison.  So far there have been 16 imported cases of dengue fever from South and Southeast Asian countries.

 

VACCINE UPDATE:

In a journal published 24 March 2006, by Zhou H. and Deem M.W., a novel vaccine procedure known as a polytopic injection can be used to elicit a host immune response to dengue fever and reduce immunodominance.  Using the polytopic injection, different vaccine serotypes are injected into different regions of the body.  These injections contain epitopes of different dengue serotypes (1-4) that are subdominant; therefore eliciting T cell responses in separate regional lymph nodes.  This will then prime the immune system to seek out the subdominant determinants instead of the cross-reactive dominant epitopes for each of the 4 dengue serotypes.  This will allow for the avoidance of an immunodominance reaction and provide the host immunity against each serotype of dengue virus.

 

References:

 

1.       Dengue/DHF update 2006 (12).  ProMed-mail.  2006.  Available at: http://www.promedmail.org/pls/promed/f?p=2400:1202:117264820838218646::NO::F2400_P1202_CHECK_DISPLAY,F2400_P1202_PUB_MAIL_ID:X,32488. Accessed April 1, 2006.

2.       Dengue/DHF update 2006 (11). ProMed-mail. Available at: http://www.promedmail.org/pls/promed/f?p=2400:1202:1730551883410139200::NO::F2400_P1202_CHECK_DISPLAY,F2400_P1202_PUB_MAIL_ID:X,32375. Accessed April 13, 2006.

3.       PAHO regional program on dengue. Pan American Health Organization. Available at: http://www.paho.org/English/AD/DPC/CD/dengue-program-page.htm. Accessed April 13, 2006.

4.       Dengue/DHF update 2006 (10). ProMed-mail. Available at: http://www.promedmail.org/pls/promed/f?p=2400:1202:1730551883410139200::NO::F2400_P1202_CHECK_DISPLAY,F2400_P1202_PUB_MAIL_ID:X,32316. Accessed April 13, 2006.

5.       Dengue/DHF update 2006 (9). ProMed-mail. Available at: http://www.promedmail.org/pls/promed/f?p=2400:1202:5629139836179426979::NO::F2400_P1202_CHECK_DISPLAY,F2400_P1202_PUB_MAIL_ID:X,32236. Accessed April 18, 2006.

6.       Dengue/DHF update 2006 (13). ProMed-mail. Available at: http://www.promedmail.org/pls/promed/f?p=2400:1202:5629139836179426979::NO::F2400_P1202_CHECK_DISPLAY,F2400_P1202_PUB_MAIL_ID:X,32553. Accessed April 18, 2006.

7.       Dengue/DHF update 2006 (16).  ProMed-mail.  2006.  Available at:  http://www.promedmail.org/pls/promed/f?p=2400:1202:12018940092736001950::NO::F2400_P1202_CHECK_DISPLAY,F2400_P1202_PUB_MAIL_ID:X,32680 . Accessed April 19, 2006.

8.       Taiwanese Government Advisory. MyEGov. 2006. Available at: http://english.www.gov.tw/TaiwanHeadlines/index.jsp?categid=10&recordid=93740. Accessed April 19, 2006.

9.       Zhou H, Deem MW. Sculpting the immunological response to dengue fever by polytopic vaccination. Vaccine. 2006 Mar 24;24(14):2451-9. Epub 2005 Dec 28.

 

 

Deepu Alex, Carlene Gong, Chelsea Johnson, Cheryl King, Anthony Ho,

Katarro Rountree, and Lisa Sani

Graduate students in the Georgetown Medical School MICB-524 course on Emerging Infectious Diseases: the Past as Prologue (Instructor, Daniel R. Lucey, MD, MPH), Master of Science Program in Biohazardous Threat Agents and Emerging Infectious Diseases.

 

 

 

Edited by: Daniel.R. Lucey, MD, MPH

EROne Institutes, Washington Hospital Center

Washington DC

Website: www.BePast.org