RESUMO
Dengue, an illness caused by dengue virus (an arbovirus), is one of the neglected tropical diseases.1 The infection is endemic in more than 100 countries. Of the estimated 390 million dengue viral infections that occur worldwide annually,2 around 1% require hospital admission.3 Since the isolation of the dengue virus in India in 1945, an upsurge has been reported in the number of cases,2 with 99 913 cases during 2015.4 Although the mortality rate of dengue is low (0.3%–0.4%),1 large financial resources required for its control5 pose a huge challenge in developing countries such as India. The dengue virus has four serotypes (DENV 1–4) and a fifth one has been reported recently.6 The most common vectors for this virus are female Aedes aegypti (A. aegypti) mosquitoes; other mosquito species that are known to transmit this virus include Aedes albopictus, Aedes polynesiensis, and Aedes niveus. Outbreaks of dengue are seasonal as the climate influences the survival of this vector.7 Transmission of dengue is facilitated by the increase in urbanization, air travel, global trade, and use of materials that support collection of water, e.g. non-biodegradable plastic products, paper cups, coconut shells, air coolers, flower pots and discarded tyres. Water collected in any receptacle makes for breeding of mosquitoes.3 Illness caused by dengue virus infection ranges from the asymptomatic non-specific viral variety to the life-threatening dengue haemorrhagic fever (DHF) and dengue shock syndrome (DSS). The typical dengue illness has three phases.3 The incubation period is followed by a febrile phase with high-grade fever accompanied by facial flushing, myalgia, arthralgia and retro-orbital pain. The ‘critical phase’ may have complications such as plasma leakage, shock and end-organ dysfunction. The ‘recovery phase’ is characterized by the resolution of symptoms and return of extravasated fluid into the intravascular compartment. Circulatory fluid overload and pulmonary oedema can occur during this period, especially in patients with comorbid conditions and due to overzealous administration of intravenous fluids.8 ‘Expanded dengue syndrome’ in some people may unusually manifest with severe involvement of organs, such as the heart, liver, kidneys and brain.1