The majority of Americans (86%) are concerned about terrorist attacks occurring while on holiday in various regions of the world in the future.

Safety concerns are prompting many to make major changes to their travel plans, according to an annual Vacation Confidence Index released by Allianz Global Assistance.

The Middle East (75%) is the region people in the US are most concerned will be the site of an attack, followed by Europe (66%) and Africa (63%).

Almost a quarter of Americans (22%) say that the fear of further violence has influenced their holiday planning in some way following recent attacks in Istanbul, Israel, Paris, Brussels and Nice.

A minority of 6% will be cancelling, while 5% plan to change locations.

Others (4%) will switch travel dates, the mode of transportation (4%), local tours (4%) or accommodations (3%).

Internationally, Americans who have changed their plans were most likely to be visiting Europe (42%), followed by Asia (29%), Latin America (26%), Australia and the South Pacific (26%), the Middle East (22%) or Africa (21%).

However, an analysis of flight bookings showed a 10% overall increase in travel to Europe during the summer, despite recent acts of terror in Brussels, Istanbul and France.

While these targeted destinations saw a significant decrease or virtually no change in US travellers visiting during the summer, Europe as a whole recorded an overall increase to 515,676 travellers in 2016 compared to 471,823 in 2015.

As Americans get older, the fear of terror attacks happening while traveling to different regions of the world increases significantly, according to the survey of more than 2,000 people.

But that trend is reversed for travel within the US and Canada, where millennials aged 18 to 34 have the greatest fear of an attack happening on home soil (57%) compared to generation X (51%) and baby boomers (48%).

An Allianz Global Assistance spokesman said: “What we’re seeing is that the American traveller is a complex demographic that shares common fears and concerns, but deviate greatly on where they find those fears and how they face them.

“But we’re pleased to see that whatever those differences are, one thing that remains consistent is that they are finding ways to follow their passion of seeing the world despite the challenges that come with travelling in a time of terror.”