A Belgian family whose daughter has been diagnosed with a life-threatening illness has raised $2 million for her treatment – thanks to a massive crowdfunding drive.

The parents of nine-month-old Pia, who suffers from spinal muscular atrophy (SMA), an aggressive genetic condition, will now be able to pay for the drug Zolgensma, which costs $2 million a dose – the most expensive medicine in the world.

It just took one week for the Antwerp-based family to reach their fundraising goal after launching a nationwide SMS campaign, seeking 2 euros ($2.20) for each text received, on the crowdfunding site GoFundMe.

"Overwhelmed" by the show of solidarity, Pia's mother Ellen De Meyer said: "When we first got the diagnosis, in my head I started to arrange her funeral. I was thinking about songs we would play, who would talk and now that's like a scenario that I can just put totally aside."

"We were really excited about that program, we said to our doctor, OK start everything up. She had the contact with the company and then they told us 'don't forget to pay the bill and that's 1.9 million euros.'"

In 40 days, the money raised will be transferred to a bank account set up for Pia, after which the family will fly to the US for her treatment. 

Zolgensma is yet to be approved in Europe.

"A wondrous medicine was invented, called Zolgensma. It is a gene therapy, administered in one shot, that will put the [missing gene] into my DNA," says a post on the TeamPia website.

"The first results of this medicine are very promising. I could lead a long, beautiful life, in which I might even learn to walk, or at least be more independent," the post added. 

A genetic condition, SMA afflicts nerves in the spinal cord and weakens muscles, thereby making it difficult for the patient to swallow, breathe or move.

Pia's parents have promised to use any remaining funds to help other families who are struggling to afford medication that could save their child's life.