Dengue facts released

Friday 17th July 2009: Heart Care Foundation of India helpline available at 9958771177 will also handle queries related to Dengue. Giving details Dr. K.K. Aggarwal said that dengue situation of not tackled in time can create an unnecessary panic situation.

Dengue is a notifiable illness. It occurs in people of all ages but is more common in children. There are four different types of dengue fever 1, 2, 3, and therefore a person in his life time can get four attacks of dengue fever or related illnesses. Subsequent attacks are more severe than the first ones. Infections from one cause life long immunity only for that strain.

Dengue is both preventable and manageable. The risk of dengue complications is in less than 1% of dengue cases and, if following warning signals are known to the public, all the deaths from dengue can be avoided.

There are four dengue related illnesses: undifferentiated fever, dengue fever, dengue hemorrhagic fever and dengue shock syndrome. Retro orbital pain presenting as pain in the eyes or pressure on eye movement is characteristic of dengue related fevers. Fever with chills is often malaria and fever with joint pains chikingunya.

The mortality for dengue hemorrhagic fever and dengue shock syndrome is around 1%. There is no mortality seen in undifferentiated fever and dengue fever. Presence of restlessness (oxygen deficiency in the brain), abdominal pain (indicating internal hemorrhage) and black stools (GI bleeding) signifies urgency.  And two dangerous clinical signs are falling systolic blood pressure and fall in pulse pressure.

Physicians should remember the formula of 20 i.e. rise in pulse by more than 20, fall of BP by more than 20,difference between lower and upper BP less than 20, platelet count less than 20, thousand and presence of more than 20 hemorrhages of blood on the arm after touniquate test suggests, high risk people who need medical attention.

If dengue is reported in one house it becomes customary for the State Health Department to search for the breeding sites around 100 houses so that the disease can be curtailed there and then. Unlike anopheles (mosquito causing malaria) which bites every 3rd day, a dengue mosquito bites 4-5 times a day. While anopheles infects one person in 3 days, aedes mosquito can infect 15 persons in 3 days.

Prevention of dengue lies with the public and not with the Government authorities. The dengue mosquitoes are found only in fresh water collected inside or outside the house and not in dirty water in nallas, flowing all over the country. Therefore dengue and malaria are not the indices of the hygiene status of a city.  Cholera and typhoid represent the hygiene indices.

It is a day biter, prefers to bite before breakfast and after lunch, prefers human sites below elbow and below knee.

A platelet count of less than one lakh signifies dengue hemorrhagic fever or dengue shock syndrome.  Do not give aspirin in the suspected case of dengue as it can further disturb the platelet functions. Never panic.  There is no need for platelet transfusion unless platelet count is less than 20,000 or there is presence of spontaneous bleeding.

IgM blood test may take 5 days to become positive.  Therefore in the first 5 days all dengue tests may be negative.

Most complications of dengue occur after the fever is over. Two days after the last episode of the fever are crucial and during this period, a patient should be encouraged to take plenty of oral fluids mixed with salt and sugar. The main complication is leakage of capillaries and collection of blood outside the blood channels leading to intravascular dehydration. Pumping fluids orally or by intravenous routes, if given at a proper time, can save complications.