Dengue is a vector-borne viral infection of global
importance. Several pathogenetic mechanisms such as
immune enhancement and selection pressure have been
proposed and febrile, critical and recovery phases have
been identified. A new classification proposed by WHO
has recently been introduced where definitions have been
changed to ‘probable dengue’, ‘dengue with warning
signs’ and ‘severe dengue’. The majority of dengue viral
infections are self-limiting, but complications have high
morbidity and mortality. The diagnosis of dengue viral
infection is essentially clinical, although confirmation
requires laboratory tests including serology, NS1 antigen
detection, PCR and viral cultures. There are no specific
anti-dengue drugs and treatment is basically supportive
and consists of early recognition of complications and
appropriate fluid therapy. A number of candidate vaccines
are under development.