Hyderabad: The advisability of giving dengue vaccine to children not affected by the disease is being debated following the outcome of trials in the Philippines. It was found that children being given the dengue vaccine in the Philippines were coming down with dengue which had led to hospitalsation.
A recent study published in the New England Journal of Medicine showed that those who had suffered from dengue and were given the vaccine were able to develop immunity.
Children who were not infected with the virus, suffered from severe dengue when they were given the vaccine.
Dr Farhan Shaikh, senior paediatrician at Rainbow Hospital, said, “The World Health Organisation has given clear guidelines that only those who have had the first infection of dengue must be given the vaccine. There is also further revision that it must not be given to children below five years of age. It has to be given from nine to 45 years.”
The approved vaccine by Sanofi Dengvaxia is now in use in 11 countries and is found to work only on those who have suffered from dengue 1 virus infection.
There are four types of dengue virus. Dr Satish Ghanta, senior paediatrician, said, that when the first one infects the body, there are mild symptoms and the immune system works to fight the virus.
“When the second dengue virus enters, the immune system is already worked up and that’s where we find that the virus is very severe. In cases that have been infected, the antibodies have been developed and the body’s fight is strengthened with the vaccine,” Dr Ghanta said adding that it has to go through trials after which work can be done to make it safe and effective.
In the Philippines trial, eight lakh school children were given the vaccine and the study found that it had helped to prevent 11,000 hospitalisations and 2,500 cases of severe dengue. But it led to 1,000 hospitalisations and 500 severe cases of dengue in children who didn’t previously have the infection.
This has led to the question whether the person must be screened with the dengue IGM ELISA test before being given the vaccine. For this the protocols have to be set where the screening must be compulsory.
The test results will state whether the person has the dengue virus or not. There have also been cases of false positives which means that there is a risk involved and it will require clinical evaluation too.
The vaccine is not available in India, but there is a major stress that dengue is a life-threatening disease and the vaccine must be introduced.
Senior paediatricians stated that it will require very strict guidelines and supply of kits to only a few centres to maintain control.
