You will end up going to the Philippines many times over future years. So, some trouble and cost now will give you peace of mind for years.

I recommend that you get Typhoid (TAB), Hepatitis A and Hepatitus B injections - they also give some protection against other waterbourne diseases. My wife and kids all have had them.

If your Tetanus is not up-to-date, say within 7 years, it's a good idea to update that also - for both PI and OZ.

Some remote rural areas have Malaria and/or Dengue Fever, so anti-mosquito preventatives are sensible (particularly as there are no cures for Dengue). The Health Department suggests malarial medicines at times, but few people worry about that. However, try the web site.