Dengue fever is an illness caused by a virus transmitted through the bite of infected Aedes mosquitoes. The symptoms of dengue fever develop in stages and can vary widely from mild to severe, often making it tricky to recognize early on. Understanding these symptoms clearly can help in timely identification and management.
After being bitten by an infected mosquito, there is an incubation period lasting about 4 to 10 days during which no symptoms appear. Once the virus starts affecting the body, dengue fever typically progresses through three phases: the febrile phase, the critical phase, and the recovery phase.
The first noticeable stage is called the **febrile phase**, usually occurring within day 1 to day 3 after symptoms begin. This stage starts suddenly with a very high fever that can reach up to 40°C (104°F). Alongside this intense fever comes a severe headache that often feels like pressure behind the eyes—a hallmark symptom of dengue. Muscle pain and joint pain are also prominent during this time; these pains are so intense that dengue has earned nicknames like “breakbone fever” because it feels as if bones are breaking inside. Nausea and vomiting may occur as well, sometimes accompanied by loss of appetite.
During this febrile stage, some people might notice swelling in their lymph nodes or glands due to immune response activation. A skin rash may also appear early on or shortly after other symptoms start; this rash can spread across much of the body and sometimes looks blotchy or patchy.
As this initial high-fever period lasts about two to seven days, many patients feel extremely weak and fatigued due to dehydration from sweating out fluids combined with poor intake caused by nausea.
Following this comes what’s known as **the critical phase**, typically around days 4–6 after symptom onset when fever begins dropping—sometimes giving a false sense of improvement. However, beneath this apparent recovery lies danger for some patients because plasma leakage from small blood vessels into surrounding tissues may begin at this point.
This leakage causes fluid accumulation outside blood vessels leading potentially to low blood pressure (hypotension) or shock if untreated—conditions known respectively as Dengue Hemorrhagic Fever (DHF) or Dengue Shock Syndrome (DSS). Warning signs during this critical window include:
– Severe abdominal pain that does not go away
– Persistent vomiting which might contain blood
– Bleeding gums or nosebleeds
– Blood appearing in vomit or stool
– Rapid breathing indicating respiratory distress
– Extreme fatigue coupled with restlessness or anxiety
These signs indicate serious complications requiring immediate medical attention since they reflect internal bleeding and organ involvement due to vascular damage caused by viral infection combined with immune system overreaction.
In milder cases where plasma leakage does not occur significantly, patients continue feeling unwell but without life-threatening complications; however close monitoring remains essential until full recovery begins.
The final stage is **the recovery phase**, where reabsorption of leaked fluids occurs gradually over several days following stabilization of vital signs like temperature and blood pressure. Appetite improves slowly along with energy levels returning toward normal but lingering tiredness may persist for weeks afterward in some individuals—a phenomenon sometimes called post-dengue syndrome involving prolonged fatigue or cognitive difficulties.
Other less common neurological complications such as encephalitis (brain inflammation), Guillain-Barré syndrome (nerve damage causing weakness), or mood disturbances have been reported but usually arise later either during severe acute illness phases or weeks afterward due to immune responses triggered by infection rather than direct viral attack alone.
To summarize key symptoms seen throughout typical dengue infection:
**Early Symptoms:**
– Sudden high-grade fever up to 104°F / 40°C
– Intense headache especially behind eyes
– Severe muscle aches & joint pains (“breakbone” sensation)
– Nausea & vomiting
– Swollen lymph nodes
– Skin rash appearing within first few days
**Warning Signs Indicatin
