Ronan Kelly
Retired 2020
Change in dengue strain observed at AIIMS lab
Durgesh Nandan Jha, TNN, Aug 22, 2010, 02.45am IST
NEW DELHI: Initial reports of laboratory experiments conducted at All India Institute of Medical Sciences (AIIMS) suggest there has been a change in the strain of the dengue virus. And this, in turn, has led to a surge in the number of cases of the vector-borne disease in the city this year.
Serum samples of the dengue virus collected from affected patients were tested at the premier institute and the results show there has been a change in the strain of the dengue virus, said sources. Microbiologists are now conducting further tests to establish the serotype.
"The findings are preliminary. Further tests have to be carried out to establish whether the change is widespread. At present, we have found new strain in two serum samples,'' said the source, adding that the new strain could be of dengue II a severe form of infection, cases of which were earlier reported in 2002 and 2004.
Dengue strains are of four types. Dengue I causes classic dengue fever, dengue II causes haemorrhagic fever with shock, dengue III causes fever without shock and dengue IV causes fever without shock or profound shock. Till now, dengue III strain has been reported in the city this season.
When contacted, Dr Shobha Broor, head of microbiology department at AIIMS, did not confirm or deny the new development. She said final reports on dengue serotype will be available after a week. "The current findings are preliminary. It is difficult to make any final comment. We will have to test more samples to make any official comment,'' she said.
Doctors say that a change in the strain or mutation might be the reason why an unusually high number of dengue cases are being reported in the city this year. The immunity to new strains is less.
"The strain has certainly changed. Many patients who tested positive for the viral infection last year have been diagnosed with dengue again this year. Normally, people who have been infected with one strain of dengue do not get infected again by the same strain,'' said Dr Sandeep Budhiraja, senior consultant, internal medicine department at Max Hospital, Saket.
Dr Randeep Guleria, professor in the medicine department at AIIMS, said if there has been a change in the strain of the virus, there was reason to worry. "Change in the strain of virus increases chances of more cases. The potency may also be higher,'' he said.
Meanwhile, 36 fresh cases of dengue were reported in the city on Saturday, taking the total number to 384 this season.
This figure does not include the positive cases reported by private hospitals and laboratories on the basis of NS1 test.
Read more: Change in dengue strain observed at AIIMS lab - Delhi - City - The Times of India http://timesofindia.indiatimes.com/...IMS-lab/articleshow/6389358.cms#ixzz0xHhlnI1s
Durgesh Nandan Jha, TNN, Aug 22, 2010, 02.45am IST
NEW DELHI: Initial reports of laboratory experiments conducted at All India Institute of Medical Sciences (AIIMS) suggest there has been a change in the strain of the dengue virus. And this, in turn, has led to a surge in the number of cases of the vector-borne disease in the city this year.
Serum samples of the dengue virus collected from affected patients were tested at the premier institute and the results show there has been a change in the strain of the dengue virus, said sources. Microbiologists are now conducting further tests to establish the serotype.
"The findings are preliminary. Further tests have to be carried out to establish whether the change is widespread. At present, we have found new strain in two serum samples,'' said the source, adding that the new strain could be of dengue II a severe form of infection, cases of which were earlier reported in 2002 and 2004.
Dengue strains are of four types. Dengue I causes classic dengue fever, dengue II causes haemorrhagic fever with shock, dengue III causes fever without shock and dengue IV causes fever without shock or profound shock. Till now, dengue III strain has been reported in the city this season.
When contacted, Dr Shobha Broor, head of microbiology department at AIIMS, did not confirm or deny the new development. She said final reports on dengue serotype will be available after a week. "The current findings are preliminary. It is difficult to make any final comment. We will have to test more samples to make any official comment,'' she said.
Doctors say that a change in the strain or mutation might be the reason why an unusually high number of dengue cases are being reported in the city this year. The immunity to new strains is less.
"The strain has certainly changed. Many patients who tested positive for the viral infection last year have been diagnosed with dengue again this year. Normally, people who have been infected with one strain of dengue do not get infected again by the same strain,'' said Dr Sandeep Budhiraja, senior consultant, internal medicine department at Max Hospital, Saket.
Dr Randeep Guleria, professor in the medicine department at AIIMS, said if there has been a change in the strain of the virus, there was reason to worry. "Change in the strain of virus increases chances of more cases. The potency may also be higher,'' he said.
Meanwhile, 36 fresh cases of dengue were reported in the city on Saturday, taking the total number to 384 this season.
This figure does not include the positive cases reported by private hospitals and laboratories on the basis of NS1 test.
Read more: Change in dengue strain observed at AIIMS lab - Delhi - City - The Times of India http://timesofindia.indiatimes.com/...IMS-lab/articleshow/6389358.cms#ixzz0xHhlnI1s