Travel health update
A new dengue vaccine has been approved for use in the UK, but the strict criteria for use mean the pre-travel assessment is vital and needs to be carried out with great care
DENGUE AND QDENGA®
Dengue (DENV) is a viral infection transmitted to humans through the bite of infected Aedes species of mosquitoes (A.aegypti and A.albopictus). There are four different subtypes of DENV and while many DENV infections produce only mild illness, DENV can cause an acute flu-like illness. Occasionally this develops into severe dengue, which can result in death, although this is rare in travellers.
Once a person has had one type of DENV infection, they will have immunity to that type in the future, but infection with another type could lead to severe dengue. UK travellers return home with DENV mostly acquired from travel to Asia, Central and South America and the Caribbean.
The World Health Organization has reported that the number of dengue cases has approximately doubled each year since 2021, with over 12.3 million cases as of the end of August this year – almost double the 6.5 million cases reported in all of 2023.
A dengue vaccine, Qdenga®, has been approved for use in the UK and a new Green Book chapter was published in October 2024. In the context of travel, the vaccine can be considered for individuals 4 years of age and older with likely history of previous dengue infection in the past and who are planning to travel to areas where there is a risk of dengue infection, or to areas with an ongoing outbreak of dengue.
Determining previous infection is key, so a very careful pre-travel risk assessment needs to be undertaken to determine the history of dengue infection, including details of previous travel to a dengue area, what the illness was like, and if there was a confirmed diagnosis of dengue infection. An infographic, (Figure 1 in the Green Book chapter 15a) is intended to help healthcare practitioners work through the steps which may be required to investigate the history. This process will take time and requires a full understanding of why these restrictions have been imposed on use of the vaccine within the UK. I have created a free of charge e-learning course, which explains the rationale behind the restrictions described in the Green Book, and I strongly recommend that you study this to obtain deeper knowledge of the subject. If risk to the traveller is high, based on the pre-travel risk assessment, then referral to a specialist travel clinic for consideration of vaccine is important and the course aims to help you understand this. A certificate for one hour of learning is also provided – see https://janechiodini.learnupon.com/store/4125159-4-dengue-course
In addition, in all cases, good mosquito bite avoidance advice should be given to travellers and you could make them aware of the resources available at https://www.janechiodini.co.uk/help/tar/NaTHNaC is also providing a webinar on dengue on Wednesday 4 December – further details can be found at https://travelhealthpro.org.uk/news/806/save-the-date-next-getting-to-grips-with-dengue-and-dengue-vaccines-webinar
TRAVEL HEALTH SURVEY
I recently undertook a survey to understand the provision of travel health in general practice. While I have more work to do on this, I’ve written a blog to share some of the initial findings, along with the link to an e-learning module, and a reminder of my Practice Nurse article, to support nurses working in England. See https://janechiodini.blogspot.com/2024/09/survey-to-understand-provision-of.html
TRAVELJOHN
Lastly on a lighter but important note, I recently came across a product to rival the ‘Shewee’ which would be very useful for those travelling – or anyone stuck on a motorway for many hours, come to that! The product consists of a strong, puncture resistant plastic bag containing an inner LIQSORB® polymer pouch that solidifies liquids instantly into a leak-proof, odourless, spill-proof gel that is non-toxic and safe for disposal in any waste bin. Take a look at https://www.traveljohn.co.uk/ for further details.