Avril Lavigne says she 'accepted death' before new song

Avril Lavigne has revealed she'd "accepted death" when writing her newest single from her sickbed "during one of the scariest moments" of her life.

The 33-year-old singer contracted Lyme disease, which is spread by infected ticks, in 2014, BBC News reports.

"I have decided to be truthful about my struggle, open and more vulnerable than ever before," she writes.

Symptoms of Lyme disease include tiredness and headaches.

It's the most common tick-borne infectious disease in the UK, Europe and North America, and the flu-like symptoms can affect some people for years.

In the letter to her fans, Avril speaks about battling her condition and "turning that fight into music".

She also talks about the importance of informing people how serious Lyme disease can be.

"To be honest, part of me doesn't want to talk about being sick because I want it to all be behind me, but I know I have to.

"Not only is it a part of my life, I need to bring awareness to the severity of Lyme disease."

The star has spoken previously about her health struggle since contracting the disease.

In 2015, Avril told US celebrity magazine People that she was stuck in bed for five months and "thought she was dying".

"I felt like I couldn't breathe, I couldn't talk and I couldn't move," she revealed.

The singer also said it took months for someone to diagnose her with Lyme disease, after previously being misdiagnosed with fatigue syndrome and depression.