Dengue hemorrhagic fever and dengue shock syndrome.
- Less than 5% of Dengue patients develop D.H.F. or D.S.S. and if warning signals are known to public all deaths from dengue can be prevented.
- Early symptoms of D H F are similar to those of dengue fever but after several days patient becomes irritable, restless and sweaty.
- Bleeding appears as tiny sports on skin.
- There can be bleeding from nose, G I tract and sometimes brain also.
In some patients disease progresses to a critical phase as fever resolves. During this phase there is leakage of plasma from small blood vessels, typically lasting 1-2 days. This may result in fluid accumulation in chest and abdominal cavity. This results in depletion of fluid from circulation and decreased blood supply to vital organs. This combined with bleeding results in steep and dangerous fall in blood pressure, this is called Dengue Shock Syndrome & this can be fatal.
Decreased level of consciousness occurs in 2-4% of severe cases which is due to either inflammation of brain by virus or indirectly as a result of impairment of vital organs like liver.