I have repeatedly heard this in an ExxonMobil TV commercial running during the 2008 Olympics coverage.

Problem:
The adjective does not belong in the sentence.

Explanation:
The word “own” has two meanings as an adjective.

The first definition of “own” is pertaining to itself or oneself, and the adjective “own” in this usage typically follows a possessive — such as “their” — to highlight the sense of ownership of that possessive.

This relates to an essentially reflexive use of “own”, as in “They earned their own money.”

The second use of “own” is as an intensifier to emphasize that the subject is the one and only actor, and the adjective “own” in this usage always follows a possessive.

This relates to an essentially intensifying use of “own”, as in “They insisted on being their own contractors.”

Unfortunately, the sentence “Malaria has touched their own lives.” calls for the adjective “own” in neither of these ways.

• It does NOT match the first usage because malaria is not acting reflexively in the sentence.
• It does NOT match the second usage because “own” does not emphasize in the sentence that the subject is the one and only agent of the “touched” action.

I fear that this form of misuse of “own” is a side effect of the increasing misuse of reflexive pronouns, as in “I am fine. And yourself (sic)?”, and as in “Please send it to Jim and myself.”

Solution:
“Malaria has touched their lives.”