There were a total of 257 prisoner deaths compared with 153 in 2006.
July was less deadly, with 20 deaths, compared with six in Iraq.
This year's count includes 33 such deaths, compared with 18 in 2005.
The total number of deaths dipped once again this year to a historic low of 59,213 deaths, compared with 59,651 in 2002.
It takes 30 years to mature ·Although sharks made 76 recorded attacks in 2001, there were only five deaths, compared with 12 the previous year.
H.I.V. and AIDS-related deaths slipped two places to seventh last year, accounting for 1,656 deaths, compared with 1,713 the year before.
And, she said, the number of deaths compared with the millions of people who visit the beaches and pools showed they are safe.
In 2012, 55 people died after being hit by subway trains in New York, an increase of eight deaths compared with 2011.
There was no statistical difference in overall mortality rates in the surgical group, which had 171 deaths, compared with the observation group, which had 183 deaths.
Since 2001, it has recorded more than 5,000 gun-related deaths, compared with the 2,000 American military deaths in the war in Afghanistan.
The WHO's mortality database for last year shows that the UK had by far the highest number of the 6,198 "yearly excess child deaths compared with Sweden" across the 14 nations – 1,951 in all.
