Dengue Vaccine- “DengiAll”The first phase III clinical trial for dengue vaccine in India was kickstarted, with the first person receiving a shot at Pandit Bhagwat Dayal Sharma Post Graduate Institute of Medical Sciences (PGIMS), Rohtak. The trial will be conducted at 19 sites across 18 states and Union Territories. It will follow 10,335 healthy adults for a period of two years.
The trial is primarily funded by the Indian Council of Medical Research, with the company partially bearing the expenses.
About Dengue Vaccine:
The vaccine called DengiAll, which works against all four serotypes of dengue, has been developed by Panacea Biotech.
— Panacea’s vaccine uses live, weakened versions of all four dengue serotypes. These weakened versions of the virus were developed by the National Institute of Allergy and Infectious Diseases in the US— they deleted parts of the genetic code of DENV1, DENV3, and DENV4 and then genetically engineered a DENV2 backbone using parts from the weakened DENV 4, on which the others were tacked.
About Dengue:
-Dengue is a mosquito-borne tropical disease caused by the dengue virus (Genus Flavivirus), transmitted by several species of female mosquito within the genus Aedes, principally Aedes aegypti.
This mosquito also transmits chikungunya, yellow fever and Zika infection.
-There are 4 distinct, but closely related, serotypes (separate groups within a species of microorganisms that all share a similar characteristic) of the virus that cause dengue (DEN-1, DEN-2, DEN-3 and DEN-4).
Symptoms associated with Dengue:
-The onset of dengue fever is usually a sudden rise in temperature lasting 2-7 days and commonly associated with headache, flushing, retro-orbital pain and/or rash, myalgia, weakness, rash and itching. Hemorrhagic manifestation (petechiae and positive tourniquet test).
– The disease has a seasonal pattern, i.e., the peak comes after monsoon and it is not uniformly distributed throughout the year. Aedes is a day time feeder and can fly up to a limited distance of 400 metres. Dengue mosquitoes can’t breed once the temperature falls below 16 degrees.
Which tests are used to detect dengue?
— IgM and IgG antibodies test and NS1 antigen test. Both are done through ELISA kits and hence are popularly known as Elisa test.
— IgM and IgG test for dengue antibodies detected in an initial blood sample, meaning that it is likely that the person became infected with dengue virus within recent weeks. This test is normally done after 3-7 days of fever while NS1 antigen test is a test for dengue, which allows rapid detection on the first day of fever, before antibodies appear.
Treatment:
As of now there is no specific treatment for Dengue. There is only supportive care which is useful in case of Dengue.
Other Ways to Counter Dengue Prevalence:
-Recently researchers from the World Mosquito Program have used mosquitoes infected with Wolbachia bacteria to successfully control dengue in Indonesia.
-The scientists infected some mosquitoes with Wolbachia and then released them in the city where they bred with local mosquitoes, until nearly all mosquitoes in the area were carrying Wolbachia bacteria. This is called the Population Replacement Strategy.
-The researchers found that the incidence of dengue was 77% lower in areas where Wolbachia-infected mosquitoes had been released, as compared to areas without such deployments.
Prevention:
-The government of India has a National Centre for Vector Borne diseases under the Ministry of Health, which updates guidelines and preventive measures for numerous vector-borne diseases like dengue, chikungunya, and malaria.
Other ways to Prevent Dengue:
-Prevention of mosquito breeding.
-Personal protection from mosquito bites.
– Awareness and Educating the community on the risks of mosquito-borne diseases.
-Active mosquito and virus surveillance.
Vector surveillance can be combined with clinical and environmental surveillance as well.