The subject matter appears to be about military veterans with HIV.

figurative meaning in Collins Dictionary

a large number of the old hands ...

Mike

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Note added at 53 mins (2011-06-07 23:35:03 GMT)
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10 out of 227,000 of "number of old hands"

END OF STRIKE RESTORES TRADE.; Business Activity Returns in ... A large number of new men have been put to work, together with quite a number of the old hands. The Wheeling and Lake Erie main line will run only passenger ...
query.nytimes.com/gst/abstract.html?res...►WILL SHAKE UP STREET CLEANERS; Commissioner Bensel to Reduce the ... They want to ask, too, about a number of the old hands who, after being in ...
query.nytimes.com/gst/abstract.html?res...Show more results from nytimes.comFlying Fifteen Berthing Checklist…. | The Flying Fifteen Blog Jun 1, 2011 ... a whole number of the 'old hands' use a sacrificial line that runs up to the hounds from the furler drum on the spinnaker halyard. ...
flyingfifteen.wordpress.com/2011/.../flying-fifteen-berthing-checklist/ - CachedModel Making Resources, Understanding Scales Particularly amongst those new to model making, but also among a good number of the 'old hands' who've simply worked around ever having to get to grips with ...
themodelmakersresource.co.uk/articles/article019.html - Cached - SimilarAdding Chicken Manure to Coir Substrate - Mushroom Cultivation ... 7 posts - 5 authors - Last post: Jun 20, 2010
Not enough folks mention it in the forums, but a number of the old hands here recommend adding 3-5% or a handful of chicken manure, ...
www.shroomery.org › ... › Mushroom Cultivation - CachedGet more discussion results
Forums - Manga Academy • View topic - Let's see how many people ... 9 posts - 7 authors - Last post: Mar 16, 2010
Just a quick browse through shows that the bots have managed to gain access, and a number of the old hands have shown back up. ...
www.mangaacademy.com/forums/viewtopic.php?f=50&t=12167 - CachedGet more discussion results
Link America...anyone have any info on them? - Truckers Trucking ... 3 posts - 3 authors - Last post: Dec 22, 2008
There have been a number of the "old hands" that decided to leave since the buyout, and those that left are doing better than if they would ...
www.thetruckersreport.com/.../63085-link-america-anyone-hav... html - CachedGet more discussion results
George John Fowell's obituary ... Meldreth, Mr SACASTON, Mr G KIDDLE, Mr F GIDDINGS, Mr E KIDDLE of St Ives, Mr R G REID Thetford etc. and a number of the old hands from St Ives. ...
www.rgreen.org.uk/GJFO.html - CachedFull text of "Red River settlement. Papers in the Canadian ... ... consequence of the difficulty of procuring a sufficient number of old hands to take the boats inland, a great number of the Old hands who were RED RIVER ...
www.archive.org/stream/.../redriversettleme00publiala_djvu.... - Cached2009 November : Unity Path :: Earthen Ring Raiding A number of the old hands were surprised by the sheer viciousness of the encounter design – this is a legitimate test. P1/P2 were sorted out to satisfaction ...
www.unitypath.org/2009/11/ - Cached

Since this is about chimps, perhaps it's anthropomorphisizing to call them 'veterans'.

[...]: a high number of the ones that have stayed there longer are HIV positive.