THE UNITED REPUBLIC OF TANZANIA


MINISTRY OF HEALTH AND SOCIAL WELFARE

Telegrams “AFYA”

Tel: 255-51-20261 General

(All letters should be addressed to

The Permanent Secretary)



P.O. Box 9083,

DAR ES SALAAM.

Tanzania


DENGUE FEVER

Standard case definition (SCD)


Dengue Febrile Illness


Suspected case definition:

An acute febrile illness of 2-7 days duration with 2 or more of the

following:

o Headache

o Retro-orbital pain

o Myalgia

o Arthralgia

o Leucopenia

o Haemorrhagic manifestations like positive tourniquet test, petechiae; purpura/ecchymosis; epistaxis; gum bleeding; blood in vomitus, urine, or stool; or vaginal bleeding) but not meeting the case definition of dengue hemorrhagic fever

Probable case - A case compatible with clinical description and with one or more of the following:

o Supportive serology (comparable IgG EIA titre or positive IgM antibody test on a single acute (preferably after 5 days) or convalescent-phase serum specimen.

o Epidemiologically linked with a confirmed case of dengue fever (occurrence at the same location and time as other confirmed cases of dengue fever)


Confirmed case

o Isolation of dengue virus from blood or tissue samples

o Demonstration of a four-fold rise in dengue specific antibody titres in paired serum samples

o Demonstration of dengue virus antigen in serum or tissue samples

o Detection of viral RNA in blood or tissue samples by polymerase chain reaction (PCR)
Dengue Haemorrhagic Fever

A probable or confirmed case of dengue with the following signs:

o Haemorrhagic tendencies evidenced by one or more of the following

o Positivetourniquet test

o Petechiae,ecchymoses or purpura

o Bleeding from mucosa, gastrointestinal tract, injection sites etc

o Haematemesis or melaena

o thrombocytopenia (100,000 platelets or less per mm3)

And evidence of plasma leakage due to increased vascular permeability, manifested by one or more of the following:

• 20% rise in average haematocrit for age and sex

• 20% drop in haematocrit following volume

• replacement treatment compared to baseline

• Signs of plasma leakage (pleural effusion, ascites, and hypoproteinaemia


Dengue Shock Syndrome (DSS)

Clinical Description for Surveillance: DSS has all of criteria for DHF plus circulatory failure as evidenced by:

o Rapid and weak pulse and narrow pulse pressure (<20mm hg="">
OR

o Age-specific hypotension and cold, clammy skin and restlessness