Delhi faces Chikungunya & Dengue trouble

Delhiites appear to be in for double trouble, going by a study conducted by the All India Institute of Medical Sciences (AIIMS) and the Indian Council of Medical Research (ICMR).

The study has found that the dengue virus, which is fast becoming hyperendemic ( constantly present at a high incidence and affecting all age groups equally), is spreading alongside the chikungunya virus. This situation is making a proper diagnosis of either disease difficult.

Dr Randeep Guleria from the AIIMS said concurrent infections could result in overlapping signs of dengue as well as chikungunya.

“ In India, the mosquito species Aedes Aegypti is the primary vector for the dengue as well as chikungunya virus. This increases the possibility of co- infections in humans. In areas where both viruses co- circulate, they can be transmitted together,” he said.

“ It is advisable that patients be tested for both viruses in areas where they co- circulate,” Guleria added.

According to the doctor, dengue had been endemic to North India. He said several serotypes, i. e. variations within a subspecies, were now co- circulating in the region, suggesting that the disease has become hyperendemic.

Also, the chikungunya virus was detected in Delhi alongside the dengue virus in 2006. “ Because their clinical features are similar, the chikungunya virus may go undiagnosed in dengue endemic areas,” Guleria said.

The AIIMS-ICMR study was conducted by a team comprising Dr Harendra S. Chahar, Dr Preeti Bharaj, Dr Lalit Dar, Dr Guleria, Dr Sushil K. Kabra and Dr Shobha Broor.

The team studied six cases that had tested positive for a dual infection during a dengue outbreak in Delhi in 2006. As many as 69 serum samples were tested then — of which 17 tested positive for the chikungunya virus. The six samples tested positive for both viruses and, of them, five recovered fully and one died.

The analysis of medical records of the six patients showed that they suffered from fever, headache, joint pain and low thrombocyte count (less than 100,000/ mm3). And of these patients, two had dengue haemorrhagic fever with central nervous system involvement.

Chikungunya cases have also been reported from Haryana, UP and Rajasthan, although these states don’t have epidemic. Scientists claim that for many years, it had appeared that the chikungunya virus had disappeared from India, but in late 2005, the virus re- emerged on Reunion Island and in India.