A bit of info fo anyone considering this unique possibility.....
Best time: April to November (could be timed for an ANZAC day service at Bomana war cemetary, which is a beautifully maintained war cemetary not far from Port Moresby, on the way to Sogeri)
Fitness: The trek requires a reasonable degree of fitness, but one does not have to be a Kenyan athelete.
Duration: The time taken would depend on the fitness ability of the trekers but 8-9 days is considered enough time. I know a porter in POM and he tells me he does it in 2-3 days on the walk back. The distance is marginally under 100km and 5-6 hours a day is walked taking about 50 hours all up.
Medical: I've spent about 3 years now in PNG (both coastal and highland regions) and I have copped nothing more than the "runs" once or twice. The travel "bomb" works well to fix that little dilemma. Malaria, dengue, zika and chikungunya are active in PNG, but usual mosquito precautions are adequate as a defence. I've not contracted any of them. Rabies, cholera and Japanese encephalitis problems are not common in PNG although typhoid and Hep A immunisation is recommended. HIV infection controls are the same as in australia.
Costs: If we get a few who are interested, I'll contact the porter I know and ask for rates. Treking can be quite reasonable.
Accommodation: Both ends of the trek, accommodation is quite good (although I have never stayed at Kokoda). Along the track, accommodation is far more modest with communal village accommodation being typical and long drop dunnies being luxurious! A shower consists of what we commonly call a waterfall! These showers are not tepid and I'd describe them as "bloody cold".
Safety: PNG has a poor personal safety reputation and in some cses it's deserved, but is generally confined to Port Moresby, Lae and the Highlands. The track is a major tourist drawcard in PNG and most of the villagers depend on the tourist kina to supplement their subsistent lifestyle and as such, trekers personal safety is somewhat assurred. There was a recent issue that made worldwide press, but in all honesty, the trekers involved should have been criminally charged. Two porters were not paid for their work as negotiated and when they fronted the pair, a bit of "argy-bargy" ensued with the outcome being unsubstantiated allegations being levelled against the porters who were promptly arrested for "their misdeeds". The truth has more recently come out however, and it turns out the pair (an American and his English girlfrind) left a trail of bad debts throughout PNG and were attempting to beat-up a Tarzan and Jane story to sell to the media. Their lies actually meant a 17 year old boy (one of the porters) was badly beaten in gaol because of "him" bringing the PNG tourism safety into a bad international focus. It was totally unfair and an extreme example of self-centred tourists that need to be brought to account for their actions. The PNG government and the PNG people are very aware of looking after their fledgling tourism industry and personal safety for the tourists is regarded as being critical and they do protect the trekers to the utmost. The Black Cat trail episode was somewhat different and unfortunately involved a tribal stouch that was witnessed by a party of trekers. Importantly, no trekers were injured and in fact, they saved the lives of some of their porters. Tribal warfare is not uncommon in PNG, but it is very uncommon for it to include people from outside the warring tribes. There were reasons for the Black Cat fight and neither parties would harm a treker.
Experience: This suggestion will not appeal to everyone, however PNG is our closest neighbour and many have never even though to visit. This could be the gloden opportunity. There are other side trips that could be added as a "recovery" bonus, like lounging in over water bures in New Island or canoeing the fjords of Tufi (I'm keen for that one especially) or even just lazing back at Loloata Island before the flight home.
POM earns little for the fare charged..........
and personal safety. Then there is cost etc. 
