This world is filled with sorrow
Phassa-pareto rogaṃ vadati attato;
Overcome by (sense-)“contact”, it calls a disease its “self” 
Yena yena hi maññati
In what ever terms they imagine it
Tato taṃ hoti aññathā.
Thereby it turns otherwise
‘‘Aññathābhāvī bhavasatto loko,
Becoming (ever something) other, the world is attached to being
Is overcome by being yet delights in being.
Yad’abhinandati taṃ bhayaṃ,
But what it delights in that is fear
Yassa bhāyati taṃ dukkhaṃ;
And what it fears that is suffering 
Bhava-vippahānāya In order to abandon being, kho pan’idaṃ brahmacariyaṃ vussati’’ this holy life is lived.
‘‘Ye hi keci All these samaṇā vā brāhmaṇā vā Ascetics and Priests bhavena who say that through existence bhavassa vippamokkham’āhaṃsu there is freedom from existence, sabbe te all of them a-vippamuttā bhavasmā’ti are not freed from beingvadāmi I say. ‘Ye vā pana keci Or all those samaṇā vā brāhmaṇā vā Ascetics and Priests vibhavena who say through non-existence bhavassa nissaraṇam’āhaṃsu there is escape from being, sabbe te all of them anissaṭā bhavasmā’ti have not escaped from being either vadāmi I
‘‘Upadhiñ’hi paṭicca Due to making something a foundation dukkham’idaṃ this suffering sambhoti is produced, sabb’upādāna-kkhayā When all taking up is exhausted n’atthi there is no dukkhassa sambhavo production of suffering. Lokam’imaṃ passa Look at this world; puthū many avijjāya paretā are those who are overcome by not-knowing bhūtā having become bhūta-ratā they delight in becoming aparimuttā unfreed; ye hi keci Whatever bhavā forms of being exist sabbadhi in any way sabbatthatāya anywhere sabbe te bhavā all these forms of being are aniccā impermanent dukkhā painful vipariṇāma-dhammā’’ti of a nature to change.
When seeing it thus
with full knowing wherever it has become 
The thirst for being will vanish
While not delighting in non-existence either.
‘‘Sabbaso taṇhānaṃ khayā,
The complete exhaustion of thirst
And complete fading away and cessation is Nibbana
Tassa nibbutassa bhikkhuno,
Such a Bhikkhu who is thus stilled
Anupādā puna-bbhavo na hoti;
Through not taking up will have no renewed being.
Abhi-bhūto māro vijita-saṅgāmo,
Mara is vanquished the battle is won,
Upaccagā sabbabhavāni tādī’’ti.
Gone beyond all forms of being is he, such like.
lit. “of the nature of burning” Parallel at SuttaNipāta 1112 here –jāta means..born/of the nature of cp PED, p. 281 where it says: — 3. ˚jāta (nt.) characteristic; pada˚ pedal character S i.86; …as adj. having become . . . (=bhūta); being like or behaving as, of the kind of . . ., sometimes to be rendered by an adj. or a pp. implied in the noun: cuṇṇakajātāni aṭṭhikāni (=cuṇṇayitāni) M iii.92; jālakajāta in bud A iv.117; chandajāta=chandika Sn 767; sujāta Sn 548 (well — born, i. e. auspicious, blessed, happy); pītisomanassa˚ joyful & glad Sn p. 94; J i.60, etc.; gandhajāta a kind of perfume (see gandha). Often untranslatable: lābhappatto jāto J iii.126; vināsa — ppaccayo jāto J i.256.
Also “citta-santāpa … “heart/mind-burn” = sorrow, so possibly: “Sorrow is the world’s nature”.
 Yes, that is exactly what is being said here: rogaṃ (a disease) vadati (it says) attato (“from, as” i.e. about the self, sg. abl – see below. ); i.e. “it (the world) says “self” what in reality is just a disease” or “what is a disease is being recognized/thought of as one’s self”.
 See “Nibbana Sermon 15”, by Ven. K. Nynananda Bhikkhu
 In other words: What we think of as “us” is “struggle” of natural forces – whatever we perceive as “us” by that very act of identifying-or grasping as me/mine turns into something else…all six senses by law of their very nature mean “change” or “becoming”. While this disease tries desparately to perceive a self something substantial where there is none, it is wrought in fear to loose it – which makes us grasp even further. To let go of that fundamental grasping, means to let go of the thirst of being and thus fear itself. Free of fear, stilled from the desire to search for something to grasp the accomplished Ones are free from any fear, having left behind even “death”.