The number of dengue cases reported in the City far exceeds that reported by the Health Department on the basis of the reports from various government hospitals.
However, experts suggest that dengue cases should be approached with clinical diagnosis and the treatment should be independent of laboratory reports.
The National Vector-Borne Disease Control Programme deals with all kinds of infections and diseases caused by mosquitoes.
The Programme has approved MAC-ELISA tests to diagnose dengue. The test identifies an antibody released from the body after the first 5-7 days of dengue fever. The time gap for confirmation of the fever prevents the patient from taking treatment in the initial stage.
Another diagnostic tool - NS1 antigen test - offers direct evidence of dengue virus in the blood. After several pharma companies have come out with kits for this type of test, the World Health Organisation standardised and approved this diagnostic method.
Private hospitals
While 70 per cent of dengue patients approach private hospitals which have adopted NS1 antigen test, the Health Department still depends on MAC-ELISA tests conducted only in government laboratories. It is also true that NS1 antigen does give false positive or false negative results.
According to Dr G Arunkumar, Professor and Head, Nodal Officer (Influenza Lab) at Manipal Centre for Virus Research, there are four types of dengue viruses - dengue 1, 2, 3 and 4.
The first three infections are found in Karnataka. He said though dengue is a 100 per cent manageable disease, the condition becomes complicated when the patient suffers secondary infection.
Primary infection occurs when dengue surfaces for the first time with only one type of virus. But in secondary infection, which implies attack by another dengue virus, the condition may lead to complications such as dengue shock syndrome or dengue haemorrhagic fever.
Irrespective of the method adopted for testing, dengue cases must be clinically handled and treatment should not depend on blood test reports, Dr Arunkumar said.
“WHO guidelines also recommend hospitalisation of the patient with dengue fever as tests are merely conducted for epidemiological purpose.
Many times, diagnosis becomes a problem as there is no standard protocol and it is practically impossible to conduct blood test for every suspected dengue case. Since dengue fever is a self limiting infection, taking care and managing the fever is more important than diagnosing or testing,” he added.
He says, dengue patients with low platelet count (a component in blood responsible for clotting) should be monitored to ensure no bleeding occurs from their body. The blood pressure of the patient also should be managed since low BP can lead to shock syndrome.
A dengue patient needs lots of fluids and rest to recover from the infection and not blood tests, he added.