Hi, everyone. Here I leave the information regarding the trip, the previous measures.
No vaccination is mandatory, they are recommended. You must to talk with the Doctor in any case, as I told you before.
But for Nepal we will not need a lot of vaccines, just a few basic ones like for example Tetanus if you do not have it updated. Ask at your hospital for hepatitis. You will see that everything there is healthy, but it is better to prevent. Anyway, it is best to ask your doctor and she/he will tell you how it should be. If Doctor says where in Nepal are you going, let’s say: Kathmandu, Bakhtapur, Lumbini and Pokhara. Tell to Doctor that you don't visit Chitwan (forest area, with many mosquito) and you don’t go anytime more than 1.300 meters on high, no Mountains I mean.
Here I give you the examples of what we have seen in Madrid and what I have vaccinated in Spain:
Typhoid vaccine. I recommend this if you also go to India, it is oral, not injected. It is not necessary for Nepal.
Vaccine against malaria. It's called Malarone. I have never worn it, I know of people who have had strong side effects such as big nightmares. Neither is necessary ..
You can bring a little traveler's personal kit with some medicine and First Aid items that can be useful, although you will not need to come very loaded with medication, keep an eye on it.
The water we drink will always be bottled. And I recommend you to make vegetarian meals, you can eat meat those who want to do so, but I recommend vegetarian meals during the two weeks we will be there. I understand that there are people who say that they do not spend two weeks without eating meat, everything is thought, and there is no problem.
Now we go with the most technical part for when you step on the Airport in Nepal. You will see that it is not necessary to do any kind of previous procedure before taking the flight.
When you arrive to Kathmandu, before taking your luggage, you will arrive at a large room where you have to fill out two documents that I enclose in the following photographs. Now I think it is no two, but only one; and there is a posibility of making all this process in a screen machine that scans your Passport, but in case, I tell you how is until now the procedure:
The first is 1/4 folio, it's small, and you see that you have to include your name without a last name (First Name), do not put anything in Middle Name if you don have; and your last name (Family Name). As you can see also ask for date of birth, sex, passport number ... Where it says "Indian nationals from India may provide other authorized ID", there do not put anything.

Expiring date: passport expiration date
Issuing Country: Austria or Spain
Flight No.: here put the flight number that took you to Kathmandu. I think many trips with Qatar, is the code of the Qatar / Kathmandu flight plane (starts with "QR" plus a number). If you travel with another company, look at the plane ticket that has taken you to Kathmandu. 
Purpose of visit: Tourism
Then it says "If Tourism", I do not put anything but if you want to put an X in "Other".
Address in Nepal is the address where you are going to locate, do not check anything, it is formal. Put: Private house in Samakhusi

You don't need to write this, I told you write better "Private house in Samakhusi", but anyway is the next:
House number 110
Yakupa Laligura Sh Tole
Samakhushi Marg

 Intended days you stay: Here you must to count the days that you will be in Nepal. All of you are different quantity of days in Nepal. Signature: your signature. IMPORTANT: Carry two passport photos with you. 2 photos.
 Signature: Signature
And at the bottom he says: "For official use only." There you do not have to write anything at all.
I know that some of you know English, that makes things easier, but I have put everything in detail because I know that there are people who do not control well. Anyway, I'll be outside, waiting for you with the van, and connected to the phones that I will provide you in case there are any incidents, which never exist.
 There are some machines that I have never used in which you go with your passport and passport photograph, scan it and say it is faster, but I have always done it in the window where there is a line and someone takes care of you. You can go to the queue and the rest go for these papers and fill them in the queue itself, to save time.
They will be two queues, the first one for the papers an payment, and the second one to go out and put in the passport the stamp. Don't care: one is first, the other is later, they will send you there. No problem. When leaving you will see that there is a bit of chaos in the line where the suitcases come. Have your eyes open, and look in all lines (there are few) where suitcases leave, because they announce it for example on line 1, and it comes out in another...
Nepal is a safe country, but walk with your eyes open. Do not lose the sticker they give you regarding your luggage when leaving your country, because in Kathmandu when leaving with your luggage the police and security usually check person by person who takes your suitcase, and corroborate it with your travel ticket. So take the ticket-plane on hand to show it to the exit because they will see that corresponds to the sticker that your suitcase has. This serves to prevent theft.
Again, Nepal is a very safe country. The only thing that is a little chaotic as you will see for yourselves ... but we will enjoy that chaos ...