Everyone who books a trip with Tell Tale Travel receives a special guest pack in the post which includes travel guidelines, cultural guidelines and Tell Tale tips. In the meantime, here is some essential information.
Travellers from the UK (as well as from 42 other countries including most of the EU, Australia, South Africa, Canada and the US) are given 30 day 'Tourist Visa Exemptions' when they arrive at the airport in Thailand. For more details on this please check the Royal Thai Embassy
website. You do not need a visa for Brazil either though for Sri Lanka you will need to do an electronic form (similar to the USA, fairly straightforward), more information in the guidelines.
Visitors from the UK are not required to have immunisations in order to visit. However, we recommend that you consult your GP or health centre about vaccinations, typically our customers have vaccinations for tetanus, hepatitis A, typhoid and polio before travelling. For Brazil, you may want to look at a yellow fever vaccination. An excellent resource for health information is NHS Scotland's Fit for Travel
If you are travelling to Thailand, have a look at their current information
We also recommend checking the Foreign Office
website for the latest updates and advice by country.