Those now behind bars are hardly kingpins, and the one headline-grabbing arrest of a top trafficking mastermind appears increasingly likely to be a case of mistaken identity.
In 2015, Italy jailed a Tunisian people smuggler for 18 years for his role in a shipwreck that killed 366 people two years earlier.
And in 2016, they handed another Tunisian an identical sentence for captaining a boat in which up to 900 people perished.
But both were the equivalent of mere drivers – a far cry from those organising the transports who rake in vast sums of cash from sending migrants to an uncertain fate on the high seas.
Although dozens of these smugglers – or “scafisti” as they are known in Italian – have been jailed, most are like Cheikhaya Dieng, a 26-year-old Senegalese man who was forced to steer the rubber dinghy that brought him to Italy.
“The judge asked me 'did you steer the dinghy?' and I said 'yes, I did, to save my life'. Because if I refused they could kill me,” he said with barely concealed anger.
“I saw others like me, they shot them in the legs,” he told AFP at the Sicilian jail where he is serving his sentence.
“But the judge didn't care, he gave me three years and eight months in prison – for nothing.”
Senegalese Cheikhaya Dieng, 26, speaks during an interview with AFP on February 15, 2019 in Trapani prison in Sicily. Andreas Solaro / AFP
Huge resources, few results
The Italian justice system, however, appears to have taken such cases into consideration: although more than 2,500 scafisti have been arrested, interior ministry figures show, only a handful have been prosecuted.
Those who do face justice tend to be the ones who reach shore in areas where the magistrates have less on their plates.
Last month, a Palermo appeals court acquitted seven crew members of a boat in which 53 migrants suffocated in 2015.
They all said they had steered the boat after being threatened.
Although the Italian authorities are desperate to get their hands on those running the show, the task is daunting, despite the impressive resources available to them.
Italian prosecutors have wide-ranging powers to probe each and every vessel headed for Italy, even if they've been intercepted or shipwrecked in international waters.
They also have an array of extensive powers drawn up in recent decades to fight organised crime, including the right to use overseas wiretaps and turncoat testimony.
On top of that, they have access to intelligence from Europe's border protection agency Frontex and from the EU's anti-trafficking mission Sophia which operates in the Mediterranean.
And they also benefit from cooperation with police in other European countries where the networks exist, including Germany, Sweden and the Netherlands.
But despite plentiful intelligence, most of the “bosses” remain safely out of reach in Libya, rendered untouchable by the chaos that has reigned there since the fall of Moamer Kadhafi in 2011.
Ivorian Fofana Lamine, 25, speaks during an interview with AFP on February 15, 2019 in Trapani prison in southern Sicily. Andreas Solaro / AFP
Top smuggler or Eritrean refugee?
Despite repeated requests from AFP, no Italian ministry or prosecutor would comment on the state of investigations.
In June 2016, Italy hailed the arrest in Khartoum of one of its most wanted – an Eritrean called Medhanie Yehdego Mered.
Known as “the General”, he was wanted on suspicion of being the head of one of the largest migrant trafficking networks that had sent thousands of migrants to Europe – and hundreds to their deaths.
But the triumph was short-lived, with serious doubts quickly arising over the real identity of the man now on trial in Palermo, who claims he is an Eritrean refugee called Medhanie Tesfamariam Berhe – whose only misfortune is to share a first name with the smuggling kingpin.
Three years after his arrest, he may have put on a bit of weight but he still doesn't bear much of a resemblance to photographs of the “real” Medhanie.
By the AFP's Fanny Carrier