Public Health Officials Confirm Highest Annual Case Count of Dengue in Texas Since 2002

Dengue Fever is a viral infection that has long plagued large parts of the globe, particularly close to the equator. From Asia to South America and even Mexico, dengue fever is a significant public health problem. Now, the first locally acquired case in the Lone Star State has been confirmed, and the annual case count has reached numbers not seen since 2002. 

What is Dengue Fever and What Causes it?

Before we jump into the Texas dengue problem, it is important to understand a little about how this disease works and how it spreads. The dengue virus, or DENV, is transmitted to humans through the bite of infected female Aedes aegypti and Aedes albopictus mosquitoes. These are distinct mosquitoes to the Anopheles, which spread malaria but are still very common in certain parts of the world, especially tropical and subtropical areas where humidity and temperatures are high. 

Mosquitos are only the vector of transmission. DENV is a disease that infects humans. Aedes mosquitos only transmit the disease from one person to another. Certain animals can also become infected and potentially spread dengue, however, this is rare and has not been studied extensively. 

If you are bitten by a mosquito carrying dengue, the disease is delivered straight to your bloodstream. However, the incubation period is around 4 to 10 days, meaning you will not feel sick immediately. Any healthcare professional, whether it's a registered nurse in Florida or a student studying online nursing programs in Texas, will tell you not to dismiss the severity of dengue fever. 

Effects and Varieties of Dengue Fever 

Once the virus has replicated in your body, the immune system will start to fight back, and you will feel either mild or severe symptoms depending on the severity of the infection and your own condition. Mild symptoms could range from fever, severe headache, joint and muscle pain (“breakbone fever”), rash, and pain behind the eyes. More severe and potentially fatal symptoms can include stomach/abdominal pain, frequent vomiting, throwing up blood or blood in your stool, nosebleeds or bleeding gums, extreme tiredness, restlessness, and irritability. 

The symptoms can vary greatly depending on which of the four distinct serotypes of the dengue virus (dengue-1, dengue-2, dengue-3, and dengue-4) you have been infected with. For instance, infections with dengue-2 are often associated with more severe disease outcomes, including a higher risk of hemorrhagic fever and dengue shock syndrome. 

On the other hand, while dengue-1 and dengue-3 can also cause severe symptoms, they are generally less likely to lead to fatal outcomes compared to dengue-2. Dengue-4, although less common, can still result in severe illness, particularly in individuals with prior infections from other serotypes. Understanding the specific serotype involved can help predict the severity of the disease and manage the treatment more effectively. 

The Texas Dengue Fever Problem 

Dengue fever is categorized in two different ways: travel-associated dengue and locally acquired. As the name suggests, travel-associated dengue happens when you catch dengue overseas, and the symptoms begin after you have flown home. Locally acquired cases are more worrying as the victim has not traveled recently enough to have acquired dengue overseas. 

In 2024, the first locally acquired infection was reported in Cameron County, an area located right at the bottom of the Teaxs coastline, next to northeastern Mexico, where dengue has been reported in the past.  

How it Spreads Around the World 

Both mosquitos that carry dengue originated in Africa; it is believed that the disease also developed in nonhuman primates living in Africa or, possibly, Southeast Asia. At some point, the disease made the jump from these primates to humans. Since then, the disease has spread around the world, with strains that were previously only found in certain areas now present in all dengue hotspots. 

Dengue has now spread to parts of the USA, Europe, and other areas where it was not previously found. This is down to a range of factors like climate change, increased travel, and poor living conditions that make it harder to protect against bites. 

The Growing Threat of Dengue Across the States

It would be great if Texas was the only state to be facing this issue but similar numbers are emerging across the country, and Puerto Rico has even declared a public health emergency because of dengue. On the Mainland US, Florida has battled with dengue outbreaks in the past. In 2010, there were 66 cases of locally acquired dengue in Key West. In 2024, 4 cases of locally acquired dengue were reported, and over 850 travel-associated cases. 

Beyond the US, dengue is now present in parts of Europe, such as France, Italy, and Spain. The disease is also commonly present in the tropical and subtropical regions of the world, like Southeast Asia, the Caribbean, Central and South America, and the Pacific Islands. Factors contributing to the geographic spread of dengue include climate change, increasing travel, and urbanization, which has enlarged the habitats of the Aedes mosquitoes that transmit the virus. 

Warmer temperatures and changing rainfall patterns expand the habitats of these mosquitoes. At the same time, urbanization results in crowded living conditions and often inadequate sanitation in poorer nations, which promotes mosquito breeding. This has made dengue a public health challenge in regions that were previously free of the disease. To combat this, organizations like the Centre for Disease Control (CDC) recommend surveillance, prevention, and control measures to mitigate its impact.

Slowing the Spread 

The fight against dengue is well underway in the US, with organizations like the CDC closely monitoring cases and working with border security to catch dengue coming into the country. Several vaccines like Dengvaxia work well to protect against the disease, but the best way to protect against dengue, and the current advice from the CDC is to avoid getting bitten. If you are concerned about dengue in your area or traveling to a hotspot, use mosquito nets, wear long-sleeved clothing, and limit exposure to mosquito breeding habitats like still water. 

Even though we are fortunate, dengue is still not a large issue in most of the US; for millions around the world, it is a fact of life. Hopefully, as time goes on, vaccines will become readily available for all, and new solutions to this pressing problem arise.

(Disclaimer: Devdiscourse's journalists were not involved in the production of this article. The facts and opinions appearing in the article do not reflect the views of Devdiscourse and Devdiscourse does not claim any responsibility for the same.)