The Impact of Climate Change on Dengue Fever Transmission
In recent decades, dengue fever has become a major risk to public health, especially in areas that are tropical or subtropical. Nearly 6.5 million cases and 7,300 deaths in 80 countries were recorded in 2023. The reasons for rising dengue fever cases include environmental causes such as rising global temperatures, changing rainfall patterns, and other climate-related issues.
Understanding the relationship between dengue spread and climate change is imperative for effectively controlling it. This blog discusses how climate change impacts dengue fever transmission in detail.
Understanding Dengue Fever
Dengue fever is a serious and life-threatening disease that is transmitted and spread by the Aedes aegypti and Aedes albopictus mosquito species. Mild fever, headaches, and muscle aches are common symptoms. Severe dengue can cause bleeding, damage to organs, and even death.
Aedes aegypti mosquitoes, which are prevalent in urban areas, play a vital role in the spread of dengue. Temperature, humidity, and rainfall are just a few examples of the variables that have a big impact on mosquito survival and reproduction, which in turn affects how the virus spreads.
Effects of Climate Change on the Spread of Dengue Fever
1. Higher Temperatures: Warmer weather promotes mosquito reproduction by speeding up the oviposition cycles and egg-laying periods.
2. Increased Humidity: Aedes mosquitoes breed and survive more successfully in environments with high humidity.
3. Urbanisation and Deforestation: Developing cities and removing forests lead to more human-mosquito contact, which increases the risk of dengue transmission.
4. Excessive Rain: Research finds that areas affected by higher precipitation are associated with increased Aedes aegypti populations, as it offers a conducive environment for breeding.
5. Disrupted Control Efforts: Natural disasters can disrupt programs aimed at controlling mosquitoes, making dengue outbreaks worse.
6. Migration: Due to climate change, individuals may be forced to relocate to places that might expose them to dengue.
7. Longer Active Seasons: Warmer temperatures extend the time mosquitoes are active, increasing the potential for dengue transmission.
How Is Dengue Fever Transmitted?
Here are a few ways dengue disease transmission can happen:
1. Mosquito Bites
Bites from female Aedes aegypti mosquitoes carrying the dengue virus are the primary means of transmission. The virus can also be spread by other species, like Aedes albopictus, also known as the tiger mosquito.
The virus grows in the mosquito before it reaches its saliva, which is how it is transmitted to humans during a mosquito bite. Depending on the temperature, it takes a mosquito between 8 and 12 days to be able to spread the virus. A mosquito that has contracted the virus might spread it for the rest of its life.
2. Human-to-Mosquito Transmission
Mosquitoes can contract the virus from humans with dengue, regardless of whether they exhibit the symptoms or not. This can happen two days prior to the appearance of symptoms and as soon as the fever subsides.
An individual’s blood contains considerable virus, which increases the possibility of infecting mosquitoes. The virus usually stays in an individual’s blood for four to five days, but it can last up to twelve days.
3. Maternal Transmission
Though it is not common, dengue can spread from a pregnant woman to her unborn child. The timing of the mother’s infection during her pregnancy determines the risk. If the mother is infected, the baby may experience problems such as low birth weight or be born prematurely.
4. Other Transmission Methods
Dengue may occasionally spread by organ transplants, blood transfusions, or the virus being passed from infected mosquitoes to their offspring.
What Are the Symptoms of Dengue Fever
The majority of dengue patients recover in one to two weeks with minimal or no symptoms. Common symptoms of dengue fever may include:
● High Fever
● Headache
● Muscle, joint or bone pain
● Nausea
● Vomiting
● Pain Behind the Eyes
● Swollen Glands
● Rash
When to Seek Medical Attention?
Severe dengue poses a serious health risk. Anyone who has recently visited a region where dengue fever is prevalent and who experiences a fever along with any warning symptoms must consult a doctor and book a dengue test with Dr Lal PathLabs for timely medical intervention.
FAQs
1. What causes dengue fever?
Dengue fever is most often caused by a bite of the Aedes albopictus and Aedes aegypti mosquito species.
2. How does climate change affect dengue transmission?
Climate change, particularly rising temperatures and increased rainfall, creates ideal conditions for mosquito breeding. Warmer temperatures help mosquitoes survive and reproduce more efficiently, which can lead to higher rates of dengue transmission.
3. What are the symptoms of dengue fever?
The symptoms of dengue fever include pain behind the eyes, fever, headache, swollen glands, vomiting, nausea, rashes and muscle, joint, or bone pain.
