A mild viral illness in most patients, dengue – the monsoon illness – generally manifests with fever, severe body aches, and headache. While in its early stages, routine blood tests usually show low white blood cells and a low platelet count. According to the National Centre for Vector Borne Disease Control, more than 12,000 cases have been reported across India, with 1,159 cases being reported from Maharashtra.

According to experts, apart from taking precautions, it is imperative to understand the initial signs and symptoms of this condition, spread by female Aedes mosquitoes. “By the fourth or fifth day, most patients begin showing signs of clinical improvement, and the fever abates without complications. However, the condition of some patients will deteriorate instead of recovering, and they progress to severe dengue. These patients need early identification and close monitoring,” Dr Tanu Singhal, a pediatrics and infectious disease specialist, told Times Now.

Also known as dengue fever, this viral illness is common, particularly in tropical and subtropical regions, and can range in severity from a mild, flu-like illness to a severe, potentially fatal condition.

The World Health Organisation classifies dengue into three clinical categories:

• Dengue without warning signs
• With warning signs
• Severe dengue

“As the critical phase begins around day four or five, it is crucial to detect patients who develop dengue with warning signs, which precede severe dengue,” said Dr Singhal. Patients in this phase may experience new or worsening symptoms that include abdominal pain, often due to liver capsule stretching or fluid accumulation in the abdomen; persistent vomiting; loss of appetite; increasing fatigue, lethargy, and drowsiness; anda decrease in urine output.

Experts say during physical examination, patients with dengue with warning signs may present with a weak or thready pulse and a narrow pulse pressure – a small difference between the upper and lower blood pressure readings. “These signs can indicate compromised circulation and plasma leakage,” Dr Singhal added. Additional physical signs of fluid leakage, such as fluid accumulation in the lungs (pleural effusion) or abdomen (ascites), should be carefully assessed. Laboratory tests play a key role in identifying patients at higher risk of complications.

The following parameters are particularly significant:

Above 40 per cent may indicate ongoing plasma leakage.

Especially when accompanied by clinical warning signs, it can signal progression to severe disease.

SGOT/SGPT > 300 IU/L are often associated with hepatic involvement.

Points to kidney involvement or significant dehydration.

The early stages of illness may correlate with a high viral load and a greater risk of severe disease.

Ultrasound imaging serves as a useful tool for supporting the diagnosis. Findings such as ascites, pleural effusion, and gallbladder wall edema are indicative of plasma leakage and may signal a more severe clinical course.

“Early recognition of these clinical and laboratory markers is essential for timely intervention and improved patient outcomes,” said Dr Singhal. Once diagnosed with dengue, patients must be advised to maintain adequate fluid intake to counteract plasma leakage and take prescribed drugs for managing fever or symptomatic treatment. Additionally, the patient must be monitored with regular blood counts every 24 to 48 hours. Clinical evaluations should also be scheduled to promptly detect any warning signs.