Dengue Outbreaks

Dengue Outbreaks 2024

According to the World Health Organization (WHO), Dengue is endemic in about 125 countries. According to an editorial published by The Lancet, 2024 has been the worst year for dengue cases on record. The WHO reclassified Dengue as a grade 3 emergency, requiring a major to maximal response. As of September 2024, the WHO's Dengue outbreak dashboard was updated, and 90 countries reported over 11 million Dengue cases and 7,009 related deaths in 2024. In June 2024, the Pan American Health Organization (PAHO) issued an Epidemiological Alert confirming the Region of the Americas has exceeded the maximum number of dengue cases historically reported in any year. As of September 2, 2024, 43 countries and territories in the Region have reported over 11,519,588 Dengue cases and about 6,478 related deaths this year. This PAHO data is over 120% greater than recorded in 2023 when 4,617,108 cases were reported.

Dengue Outbreak Travel Advisories

The U.S. Centers for Disease Control and Prevention (CDC) reissued a Global Travel Health Notice on August 14, 2024, regarding dengue outbreaks in 26 countries, including the Americas, Africa/Middle Eas t, Costa Rica, and Asia/Pacific Islands. As of August 2024, HealthMap published dengue case maps.

Dengue Outbreak United States

In June 2024, the U.S. CDC updated a Health Alert Network Health Advisory to notify healthcare providers, public health authorities, and the public of an increased risk of dengue virus infections in the United States in 2024. The CDC reported that 53 jurisdictions, led by Florida, New Jersey, New York, and Puerto Rico, reported 4,117 dengue cases as of week #33, August 28, 2024. In 2023, 52 U.S. jurisdictions reported 2,343 dengue cases to the CDC.

As of August 28, 2024, the Florida Health Department (FDH) reported travel-associated and locally acquired dengue cases throughout the state. In 2024, Puerto Rico's Department of Health confirmed Dengue was endemic in the greater San Juan area. The Texas Department of State Health Services (DSHS) says mosquitoes that transmit dengue fever are found in Texas, with (34) cases reported in sixteen counties, led by Collin (5) and Travis (5) on August 13, 2024. There were 79 dengue cases in Texas in 2023, including one locally acquired case in Val Verde County.

Dengue Outbreak U.S. Territories

The CDC says Dengue is endemic in the U.S. territories of Puerto Rico, American Samoa, the U.S. Virgin Islands, the Federated States of Micronesia, the Republic of Marshall Islands, and the Republic of Palau. Of American Samoa school-aged children, the estimated seroprevalence among those aged 7–16 years was 59% (95% CI = 47%–71%) and was 60% (95% CI = 48%–72%) among those age-eligible for vaccination.

Dengue Outbreaks Africa

The CDC reported in January 2024 that travelers visiting these African countries may be at increased risk for Dengue: Burkina Faso, Cape Verde, Côte d'Ivoire, Ethiopia, Mali, Senegal, and Sudan. In 2023, 171,991 dengue cases and 753 deaths were reported in African countries. Dengue circulation has been detected in more than 30 African countries. The U.S. CDC issued a Travel Health Notice in 2023, confirming Dengue is an ongoing risk in Africa.

Dengue Outbreaks Region of the Americas

The first suspected dengue-like epidemics were reported in 1635 in Martinique and Guadeloupe. In 2024, the U.S. CDC reported that countries in the Americas had severe dengue cases. On May 24, 2024, the PAHO announced that Brazil, Argentina, Paraguay, Peru, Colombia, and Mexico had the highest reported dengue cases.

As of 2024, Brazil reported over 1 million dengue cases. The Brazilian Ministry of Health reported dengue cases among pregnant women reached 5,151 in the first six weeks of 2024, compared to 1,157 in the same period in 2023. In 2023, Brazil reported about 2.9 million patients, a one-year increase of 20%. In 2023, Rio de Janeiro reported 22,959 dengue cases.

According to the Republic of Costa Rica Health Surveillance Directorate, 1,076 dengue cases were reported in 2024. Costa Rica confirmed over 24,000 dengue cases in 2023, with the Huetar Caribe and Central Sur regions presenting the most cases. As of August 4, 2023, all four dengue serotypes were registered.

Mexico reported more than 65,000 cases of Dengue in 2024. The states that reported the most cases were Quintana Roo (Cancun), Tabasco, and Guerrero. Dengue was reported in 28 of 32 Mexican states in 2023, and transmission has been documented in Yucatan since 1979. All four DENV serotypes have been found in Mexico for decades.

As of 2024, the PAHO reported continuing widespread transmission of dengue fever in the Caribbean. On August 16, 2024, the Republic of Trinidad and Tobago confirmed 825 cases of Dengue Fever and eight (8) laboratory-confirmed deaths. The Caribbean reported over 62,000 dengue cases in 2023, a significant increase from 20,349 cases in 2022. Jamaica's Ministry of Health declared a dengue outbreak on September 23, 2023.

Dengue Outbreaks Asia and Pacific Islands

The U.S. CDC reported in 2024 that the countries listed in the WHO Western Pacific Region are reporting higher-than-usual dengue cases, and travelers visiting these countries may be at increased risk: Bangladesh, Cambodia, Malaysia, Philippines, Singapore, Sri Lanka, and Thailand. According to data from the National Centre for Vector-Borne Diseases Control Program, India reported 289,235 dengue cases and 485 related deaths in 2023.

Dengue Outbreaks Eastern Mediterranean Region

Dengue and severe dengue epidemics were first reported in the WHO's Eastern Mediterranean Region in 1998. Dengue outbreaks occur in all nine endemic countries: Afghanistan, Djibouti, Egypt, Oman, Pakistan, Saudi Arabia, Somalia, Sudan, and Yemen. On July 17, 2024, the WHO reported 12 autochthonous (local) cases of Dengue documented in Iran. Dengue screening at the Iranian border was launched in August 2024.

Dengue Outbreaks Europe

The European Centre for Disease Prevention and Control (ECDC) reported locally acquired dengue cases in France, Italy, Spain, and Croatia on August 16, 2024. In 2024, France reported 21 locally transmitted dengue fever cases from Alpes-Maritimes (2 cases), Drôme (2 cases), Gard (1 case), Hérault (1 case), Pyrénées-Orientales or Lozère (2 cases), Vaucluse (10 cases), Var (3 cases) departments. Imported dengue cases in Europe increased from 1,572 in 2022 to about 4,900 in 2023.

Dengue Carrying Mosquitoes

A recent study published by the Royal Society indicates that dengue-carrying mosquitoes are expanding their range by an average of 6.5 meters of elevation and have moved polewards by 4.7 km annually.

Dengue Disease

Dengue is a disease caused by a virus spread through mosquito bites. The disease can take up to 2 weeks to develop, with illness generally lasting less than a week. Without treatment, severe Dengue can become fatal. New research has identified pre-existing anti-DENV IgG antibodies responsible for Dengue's increased deadliness upon second exposure. "We definitively proved that it's not the presence of dengue antibodies that are a problem, but the quality of those antibodies," says Stylianos Bournazos, a research associate professor in the laboratory of Jeffrey Ravetch, the Theresa and Eugene M. Lang Professor at Rockefeller University in New York.

Severe Dengue

About 5% of infections lead to severe Dengue, a life-threatening disease. Promptly initiating intensive supportive therapy can reduce the risk of death among patients with severe Dengue. The extent and duration of viremia often appear to be associated with clinical disease severity. However, there is a significant difference in the kinetics of viremia, nonstructural protein 1 antigenemia, and pathogenicity between the serotypes and genotypes of the dengue virus.

Dengue Virus Pregnant Women

The CDC confirms a pregnant woman already infected with Dengue can pass the virus to her child during pregnancy, and there has been one documented report of Dengue spread through breast milk. A study published in the American Economic Journal: Applied Economics in April 2024 confirmed robust evidence for the negative effect of dengue infections on birth weight and documented increases in children's hospitalizations and medical expenditures for up to three years after birth.

Dengue and Zika Virus

The journal Science Translational Medicine published a study on May 29, 2024, finding that primary ZIKV infection increased the risk of disease caused by DENV3 and DENV4 but not DENV1. This finding was also factual for tertiary infections when individuals were previously infected with DENV and ZIKV but not when previously infected with ZIKV and DENV.