do water purification tablets kill all bugs everywhere?

[Tutter]

or are they designed to purify western water - anyone know? asking on behalf of a friend who'ss off to sri lanka this w/end with a 12 mo. thanks.

'Chlorine i.e.AQUATABS Advantages: taste preferable to iodine; suited to long term use.
Disadvantages: takes 10 mins; not totally effective against Giardia and Amoebic Cysts, therefore not suitable for under developed countries unless used with a filter'

quoted from travelwithcare website.
Surely bottled water will be available in Sri Lanka?

thanks gb. yes, in some places, but they're heading off the beaten track for a few days. also, won't be able to carry enough (need to make up feeds as well as drinking water for them).

They need to take a small portable filter in addition to tabs then - most camping shops sell them.