Combining efforts to mitigate the impact of the dengue epidemic in Central America and the Dominican Republic
Dengue is a febrile illness that affects all ages and is caused by the dengue virus (DENV). The infection is characterized by the presence of fever, headache, myalgia, arthralgias, among others. However, in the absence of adequate management, it progresses to severe dengue, characterized mainly by hypovolemic shock. (1)
Dengue is the most common arbovirus globally (2). In the Americas, it is the cause of epidemics that recur every three to five years. The occurrence of dengue cases has been associated with changes in climate. Increased rainfall and warmer months provide an ideal scenario for breeding sites for the mosquito responsible for transmission: Aedes aegypti. (3)
Data collected since 1980 in this Region show an increasing trend in the number of cases, from 1,6 million in the 1980s to 18,2 million in the 2010s. 2023 is the year with the highest number of dengue cases in the Americas. As of epidemiological week (EW) 45 of 2023, 4,1 million cases have accumulated, with a cumulative incidence of 409 cases per 100 000 inhabitants, including 6214 severe cases and 1910 deaths (case fatality 0.047%). (4)
The picture in the subregion of Central America and the Dominican Republic is not very different with a total of 260 032 cases of dengue as of EW 45 of 2023, being the year with the highest number of cases reported after 2019 in which the largest epidemic outbreak was recorded with 418 702 cases. This number is expected to continue to increase in the coming months and its increase will extend until the first half of 2024, because of the climatic conditions due to the El Niño phenomenon. (3,4).
This increase has placed an additional burden on health systems in areas of high transmission, already weakened by the COVID-19 pandemic, leading to the declaration of health emergencies in some countries. In addition, chikungunya outbreaks also contribute to the health and economic burden on health systems and society. (4,5)
Regarding the costs of dengue for society and health systems in Latin America, it is estimated that the total costs of an ambulatory case of dengue were I$ 224 (2014) in El Salvador, I$ 193 in Guatemala and I$ 648 in Panama. Similarly, the cost of a hospitalized dengue case was I$1,171 in El Salvador, $917 in Guatemala, and $2,079 in Panama, representing a high economic burden on health care services and society. (6,7)
These factors make the situation in the Central American isthmus more complex due to the current situation of human mobility, the El Niño phenomenon, which causes droughts with significant crop losses and higher rates of food insecurity, reduced availability of drinking water, agriculture and hydroelectric generation, intense floods that cause damage and displacement, rising temperatures and wildfires, increased incidence of vector-borne diseases and waterborne diseases. (3,8-9)
Given that to date there is no specific drug to treat dengue, early detection and adequate clinical management of cases and community participation are the only tools available to prevent the disease from progressing to a more serious condition, with the consequent reduction in the risk of death (1).
In recent years, national coordination networks and public health surveillance capacities have improved. However, there are still gaps in the processes of collecting, capturing, and generating quality epidemiological data, as well as clinical diagnosis and case management at the point of service. Epidemiological surveillance for early detection and timely response to dengue should be intensified in the subregion given that environmental conditions for Aedes aegypti will be more favorable in the coming months.
The Pan American Health Organization/World Health Organization (PAHO/WHO) through the Regional Program on Arboviral Diseases (CDE/VT) and the Department of Health Emergencies (PHE), in conjunction with the Executive Secretariat of the Council of Ministers of Health of Central America and the Dominican Republic (SE-COMISCA), have developed a plan, with the participation of the Central American Regional Office (CAR) of the Centers for Disease Control and Prevention (CDC-CAR). CDC-DVDB and CDC-Dengue Branch, with strategies focused on strengthening epidemiological, laboratory, and entomological surveillance, clinical management capacities, risk communication and community engagement, and emergency coordination and management for the control of dengue, chikungunya, and Zika during the period of greatest transmission of these diseases (August-December 2023).
This plan is part of an anticipatory planning process that began on July 5, accompanied by the issuance of an epidemiological alert issued by PAHO on July 31, 2023, with an emphasis on Member States in the Central American subregion reviewing and adjusting their preparedness and response plans to address outbreaks of dengue and other arboviruses to prevent complications and deaths associated with these diseases. (10)
In addition, two epidemiological alerts were published to guide countries in the implementation of strategies to reduce risk and impact, especially on the most vulnerable populations; review and update preparedness and response plans, maintain surveillance, early diagnosis, and timely treatment of cases of dengue and other arboviruses to prevent complications, and reduce severe cases and deaths associated with these diseases. (11, 12)
Facing these challenges requires a multidisciplinary approach and collaboration between health systems, governments, international organizations, and communities. Investment in staff training and technological tools can help improve the prevention and control response to these arboviruses (13-15).
The Integrated Management Strategy for the Prevention and Control of Arboviruses (EGI-Arboviruses) in Central America (15) is a working model that integrates several key disciplines to address technical, logistical, and financial challenges related to the prevention and control of these arboviruses. In management, it is necessary to strengthen coordination and harmonization between each of the components of the EGI-Arbovirus to ensure comprehensive decision-making based on the analysis of quality information generated by surveillance systems. The collection and generation of epidemiological data must be improved, supported by the automation of these processes that allow real-time analysis and the generation of timely interventions. Strengthening the knowledge of early clinical diagnosis and treatment is key to preventing progression to severe forms and deaths from this disease. Laboratory surveillance is also key, so the availability of reagents for the confirmation of these cases must be guaranteed, prioritizing those that are serious and those that occur in areas of new circulation. Integrated vector management should focus on risk stratification, directing control actions to areas of increased dengue transmission.
In this regard, PAHO and SE-COMISCA, in collaboration with other partners, have strengthened their efforts to address the challenges faced by the complex epidemiological context of dengue fever and arboviruses in the subregion. To this end, it is crucial that health organizations continue this joint effort to generate appropriate preparedness and response actions to face and mitigate the impact of the epidemic.
References
1. Pan American Health Organization. Dengue: Guidelines for the Care of Patients in the Region of the Americas. PAHO; 2016. Available from: https://iris.paho.org/handle/10665.2/28232?locale-attribute=es
2. Du, M., Jing, W., Liu, M. et al. The Global Trends and Regional Differences in Incidence of Dengue Infection from 1990 to 2019: An Analysis from the Global Burden of Disease Study 2019. Infect Dis Ther 10, 1625–1643 (2021). https://doi.org/10.1007/s40121-021-00470-2
3. Reinhold JM, Lazzari CR, Lahondère C. Effects of the Environmental Temperature on Aedes aegypti and Aedes albopictus Mosquitoes: A Review. Insects. 2018 Nov 6;9(4):158. doi: 10.3390/insects9040158. PMID: 30404142; PMCID: PMC6316560.
4. Pan American Health Organization. Health Information Platform for the Americas. PLEATED. Reported cases of dengue in the Americas. PAHO; 2023. Available from: https://www3.paho.org/data/index.php/es/temas/indicadores-dengue/dengue-nacional/9-dengue-pais-ano.html
5. Pan American Health Organization. Health Information Platform for the Americas. PLEATED. Chikungunya cases by country and territory. PAHO; 2023. Available from: https://www3.paho.org/data/index.php/en/mnu-topics/chikv-en/550-chikv-weekly-en.html
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8. Ferreira MC. Geographical distribution of the association between El Niño South Oscillation and dengue fever in the Americas: a continental analysis using geographical information system-based techniques. Geospatial health. 2014 Nov 1;9(1):141-51.
9. Rao VB, Maneesha K, Sravya P, Franchito SH, Dasari H, Gan MA. Future increase in extreme El Nino events under greenhouse warming increases Zika virus incidence in South America. npj Climate and Atmospheric Science. 2019 Jan 29;2(1):4.
10. Pan American Health Organization. Epidemiological Update. Dengue in the Region of the Americas. July 5, 2023. PAHO. Available from https://www.paho.org/es/documentos/actualizacion-epidemiologica-dengue-region-americas-5-julio-2023
11. Pan American Health Organization. Epidemiological Update. Dengue in the Central American Subregion. July 31, 2023. PAHO. Available from: https://www.paho.org/es/documentoactualizaciónon-epidemiologica-dengue-subregion-centroamerica-31-julio-2023
12. Pan American Health Organization. Epidemiological Update. Increase in dengue cases in Central America and the Caribbean. September 15, 2023. PAHO. Available from: https://www.paho.org/es/documentos/alerta-epidemiologica-aumento-casos-dengue-america-central-caribe-15-septiembre-2023
13. Alvarado-Prado R, Nieto López E, Ramírez Rojas M. Challenges in the implementation of the Integrated Management Strategy for the prevention and control of dengue, Costa Rica 2016. Cuban Journal of Tropical Medicine. 2020 Aug; 72(2).
14. Fernandez PE, Paz AM, Martin YF, Viera IR. Evaluation of the integrated management strategy for the control of a dengue epidemic. Medicecum. 2010 Jan 1; 16(4).
15. Pan American Health Organization. Integrated Management Strategy for the Prevention and Control of Arboviral Diseases in the Americas. Washington: PAHO; 2019 Available from: https://iris.paho.org/handle/10665.2/51787