Health
Before arriving to Vanuatu, check with a Travel Doctor about what vaccinations are recommended for Vanuatu and make sure all your vaccinations are up to date prior to travel. Check out Smart Traveller's recommendations.
Malaria has been eliminated in Tafea Province, but Dengue can be present especially in the wetter months. You may wish to take anti-malaria tablets anyway if you are travelling to other islands in Vanuatu. It is a good idea to wear clothing that decreases your chances of being bitten and carry some mosquito repellent with you.
In general, the tap water in Tafea Province is not suitable for drinking, unless where you are staying has filtered water it is best to use bottled water for drinking and avoid ice made from tap water.
All the local fruits and vegetables are organic in Tanna, you may prefer to peel raw vegetables and fruits prior to eating them but most tourism hosts have learnt how to clean and wash all vegetables and fruits and prepare food hygienically for international visitors.
It would be best to carry your own First Aid Kit as there are no pharmacies in Tanna and there are only limited supplies at the local hospital. Due to the tropical climate small cuts and insect bites can become infected easily, so pack a good topical antiseptic and bandaids, rehydration tablets and anti-nausea tablets would be useful too. Use plenty of sunscreen lotion.
There are no dangerous animals or insects in Vanuatu (except mosquitos).
Safety
The usual travel precautions are advised for travelling in Vanuatu as in most countries. You may find it better to travel in a group rather than alone, especially as a female. Have photocopies of your passport, tickets and credit cards in case the originals are lost.
Find out about the travel tips before arrival to ensure that you are following the cultural normalities and not putting yourself at a higher risk than you need too.
In general, the people of Vanuatu are open and friendly and as long as you respect their culture they will respect yours and by taking some precautions as mentioned above, you can ensure that your trip to Vanuatu will be both safe and fun.