Mosquito warning for British holidaymakers as imported infections return to pre-pandemic levels

The UK Health Security Agency has warned British holidaymakers about the dangers of mosquito-borne diseases, as new data shows imported cases of illnesses including malaria, dengue and zika are back to pre pandemic levels.

International tourism was hit hard by the pandemic but now, two years after all travel restrictions were lifted in the UK, the sector is booming again.

Increased global travel has in-turn left British tourists vulnerable to serious mosquito-borne infections, such as dengue and malaria, that are typically only detected in tropical climates, warned the UK Health Security Agency.

The latest UKHSA data shows that there were 634 dengue cases reported by travellers returning to the UK in 2023, alarmingly close to the 790 cases reported in 2019, during the pre-pandemic period.

Dr Philip Veal, a consultant in Public Health at the UKHSA, warned British holidaymakers travelling abroad to be aware of the risk and to avoid bites. “Even if you have visited or lived in a country before, you will not have the same protection against infections as local people and are still at risk,” he said.

Over the past year dengue, or “break-bone fever”, has spread across much of the tropics. South and South-East Asia, particularly India, have been hard hit, and there have been major outbreaks across Central America and the Caribbean.

It is thought that climate change together with ever increasing urbanisation is aiding the boom of the Aedes Albopictus, or the ‘Asian tiger mosquito’ – the insect responsible for spreading the disease.

Major dengue epidemics typically occur cyclically – every three to five years. But the WHO reported a significant rise in global dengue incidence in 2023, with more than five million cases and 5,000 deaths reported worldwide.

Although the death rate for dengue is generally low, some 500,000 people are hospitalised annually, with many more experiencing symptoms including fatigue and brain fog that can last for weeks.

Similarly, the WHO’s annual World Malaria Report for 2023 warned that efforts to eliminate malaria are at a “crunch point”, with climate change extending the length of malaria seasons and affecting the accurate timing of seasonal interventions.

‘Plan ahead’

Climate is also related to the spread of Anopheles stephensi, the malaria-carrying ‘super mosquito’ famous for surviving in high temperatures in dry seasons, when malaria transmission typically dips.

The number of confirmed malaria cases in the UK, from the period January to October 2023, totalled 1,637.

Eight Zika cases were reported in England in 2023, a similar level to 2022 but far below the peak in 2016, when cases reached 725 during a large outbreak across the Americas. 

While cases of Zika are low, the disease is particularly harmful for pregnant women as it has been linked to birth defects.  

Dr Dipti Patel, Director of the National Travel Health Network and Centre, urged people to “plan ahead” and speak to their GP six weeks ahead of travelling to help ensure they have all the necessary vaccinations, repellants and medications. 

The latest foreign travel advice, including guidance on disease, safety and security warnings, for every country in the world can be checked on the government website.

The NHS tells holidaymakers to check for malaria before travelling and says you may be prescribed preventative antimalarial tablets, that you should start taking a few days before you go.

There is no vaccine available in the UK to prevent zika  but you can reduce your risk of catching the virus by avoiding mosquito bites.

The NHS recommends that you wear loose, long-sleeved clothing and trousers to cover in the evenings and mornings when the insects are most active.

Also, take a good quality, Deet-based, insect repellent, and sleep under a mosquito net treated with insecticide.

There is now a vaccine called QDenga available in the UK to prevent dengue. The course consists of two doses given three months apart and protects against all four strains of the virus.

But the vaccine is only for individuals over the age of four who have had confirmed dengue infection in the past and are planning to travel to areas at-risk.

Protect yourself and your family by learning more about Global Health Security