Somia Iqtadar, MBBS, is an associate professor of medicine at King Edward Medical University, Pakistan, and chairperson of the Dengue Expert Advisory Group.
What is the role of immunization in dengue prevention in endemic countries and in international travelers?
Dengue is a major problem worldwide, especially in the tropical countries, but it is not limited to the tropical countries only. It is further expanding to the United States, to Portugal, to Tokyo, to Japan. Now more than 130 countries are reporting dengue cases. More than 4 billion people are affected by dengue. It is the fastest growing infectious tropical disease, which is spread by mosquitoes.
For a very long time we’ve been waiting for an effective and safe dengue vaccine. A dengue vaccine with the name Dengvaxia was launched a few years back. It was not very successful because there are specific indications for which this vaccine can be given. It can be given only to people 9 to 45 years of age and people who have been previously hit by dengue. So they need to have the seroprevalence of dengue checked before giving this vaccination. It is a 3-dose vaccination, which is [administered] 6 months apart. It’s not routinely recommended in most of the countries. Some resource-limited countries with a high burden of disease where the seroprevalence data are present are the only countries where we give this vaccine. It is not recommended for travelers at the moment.
Another vaccine, QDENGA by Takeda, has recently been launched. It is now being used in Indonesia, the first country that has given approval for the authorization for the use of this vaccine. It’s a tetravalent vaccine covering all the 4 strains of dengue. It is a 2-dose vaccine and you do not need prior testing of dengue for this.
I think this is a major breakthrough in the dengue scenario and in the future this might be used for travelers who are going to endemic areas for prevention of dengue.