Dr Aju Mathew lists 2 updates on dengue
M3 India Newsdesk Sep 10, 2021
The incidence of dengue has grown dramatically around the country in the past few years. In this article, Dr. Aju Mathew expounds on the nature of the disease and a successful trial study along with updates on a dengue vaccine.
We have just encountered the devastating consequences of another viral infection in the North of India, the state of UP. Numerous deaths, including those of children, have been reported from the region due to the vector-borne illness, dengue fever.
It is one of the top 10 global public health threats as nominated by the World Health Organisation. The best way to prevent dengue fever is to eliminate the vector – Aedes aegypti. Mosquito breeding has increased due to the secondary effects of urbanisation and climate change. I don’t think eliminating Aedes aegypti is even possible given the rapid urbanisation and the poor sewage drainage systems that exist in our urban centres. What else could be done?
Introgression of bacteria into mosquitoes – a cluster trial
It was only recently that we had seen astoundingly amazing results from a cluster randomised trial from Indonesia.[1] Here’s a gist of what was done. Aedes aegypti mosquitoes were infested with a type of bacteria called Wolbachia pipientis. The unique nature of the bacteria is such that it introgresses into the mosquito and blocks the infection of the vector with the dengue virus.
In the trial, 24 clusters of Yogyakarta city in Indonesia were randomised to receiving deployments of the bacteria-infested Aedes or no deployments. The results were remarkable. In the deployed clusters, only 2.3% of the population had virologically confirmed dengue (VCD) versus and 9.4% in the not-deployed control cluster. A remarkable 77% risk reduction of dengue infections was seen. There were fewer hospitalisations as well.
The elegantly done trial needs to be studied by policymakers in urban centres in India. If it is feasible to be done in India, I can’t see why not, we must replicate it here. The number of lives saved justifies the biological manipulation of the vector species.
ADE – A trojan horse complication of dengue
Developing a vaccine against dengue has been extraordinarily challenging especially due to the problem of antibody-dependent enhancement (ADE).
In this instance, the antibodies that develop in a person’s body after an infection or vaccination can act as a trojan horse and allow for more virulent infection with the dengue virus. Subsequent infections can become more serious as a result of the ADE. In 2016, a dengue vaccine trial conducted in the Philippines resulted in concerning findings among young children less than 9 years of age.[2] It was thought that ADE could be the aetiology for the complications seen in the trial.[3]
While we were developing the vaccine against SARS-CoV2, there was a lot of discussion and concern about whether there is a risk for ADE with the novel coronavirus. Fortunately, now we know that there is no risk for ADE with the vaccines that are currently available against COVID-19. For that, we must be grateful to the global vaccine scientists.
I wonder if the mRNA technology will now help us devise better vaccines against dengue virus infection as well. Let’s hope and pray that the breakneck pace of scientific progress that we saw in the last one year will translate into success against infections such as dengue as well.
To read Dr. Aju Mathew's previous articles, click here: Dr Aju Mathew picks 3 clinical updates you should not miss, Dr. Aju Mathew lists 4 new updates in diabetes treatment, Dr. Aju Mathew presents top 3 updates on antibiotics, A hidden side effect of COVID-19 on children: Dr. Aju Mathew, Dr. Aju Mathew reviews 3 crucial studies on liver disease & New insights on LDL lowering therapies: Dr. Aju Mathew
Click here to see references
Disclaimer- The views and opinions expressed in this article are those of the author's and do not necessarily reflect the official policy or position of M3 India.
Dr Aju Mathew is a medical oncologist, haematologist, internist and epidemiologist practising in Kochi.
-
Exclusive Write-ups & Webinars by KOLs
-
Daily Quiz by specialty -
Paid Market Research Surveys -
Case discussions, News & Journals' summaries
