Teenage girls often have secrets, but 18-year-old Amelia* is more practised than most at keeping her secret.
She says: "It's like you're living a secret life. You take your medication every day, but you can't tell anyone about it, because you don't know how they will react.
I don't feel like anyone with any other illness has to do that. If you have cancer or diabetes you can just come out with it, but with HIV you have to hide a part of yourself from everyone.
Amelia is one of around 3,100 Brits under the age of 24 who is currently receiving care for HIV (human immunodeficiency virus), according to figures from Public Health England.
Unlike teenagers living with other medical conditions, Amelia says she cannot rely on the support of her friends and classmates and has keep silent about her HIV status.
"I don't feel comfortable disclosing such a personal part of my life, because of the stigma around HIV," says Amelia. "I feel like if you so much as mention it, people assume that you've been sleeping around, or they think that you can't hold hands without catching it.
"That's what I find really difficult. But actually I can't blame people for thinking that way. When I first learned that I had HIV I thought you could catch it from toilet seats or by sharing a cup.
We never learned about HIV in school, which is sad, because the lack of understanding makes life harder for people who are newly diagnosed.
Amelia was born with HIV – a virus which attacks the body's immune system.
It can be transmitted from one person to another through unprotected sex, sharing needles to inject drugs, or – as in Amelia's case – it can be passed from a mother to her child during pregnancy, birth or breastfeeding.
But it cannot be 'caught' from cups, toilet seats or exercise equipment. Nor can it be passed on through a hug, kiss or handshake, as prevailing myths about the virus would have you have believe.
Doctors often wait until children who are born with HIV are old enough to understand the difference between facts and fiction about the condition, before telling them that they are HIV-positive.
"It is not uncommon for doctors to hold off beginning the process of telling a child that they are HIV positive until they are between nine and 13 years old," explains Polly Balsom, spokesperson for Body & Soul, a charity that supports teens and families living with HIV.
"The process of naming HIV involves reconciling various factors to find an ideal age for each child. These considerations include whether the child is mature enough to understand what it means to be HIV positive; if they understand what the implications of that knowledge being made public might be; the fact that children have a right to know about their own health and that many children are more mature at a younger age than they are often given credit for."
Amelia was told that she was HIV positive when she was 11. It was the first time she had ever heard about the condition.
"I was scared and I didn't understand what it meant," she recalls. "The doctors tried to explain it to me, but to be honest I didn't take any of it in. I just thought it meant I was dying - that I was going to live a short unhealthy life and wouldn't be able to do the things that a normal 11-year-old girl would do.
"I didn't want to believe that this was something I would have to deal with every day of my life, for the rest of my life."
Amelia has five brothers and sisters, two of whom are also HIV positive. Her siblings are a great source of support.
"My mum didn't want to accept it, she was in denial and so she couldn't help me understand," says Amelia. "But my two big sisters sat me down and talked to me about it. That helped a lot. But it didn't change the fact I now had a secret to keep from my friends."
Parents of children with HIV are not legally obliged to tell their child's school or college about their child's condition.
According to the National AIDS Trust there has never been a known case of HIV transmission in a school. But sadly sometimes students who have disclosed their HIV status to their school have faced discrimination, which is why many people, such as Amelia, choose not to tell anyone at their school about their condition.
Amelia says it hasn't been too difficult to keep her condition a secret at school, as HIV is not a topic that often comes up in teenagers' conversations.
"It's not something that ever really comes up with my friends," she says. "But there was one time a friend made a comment about not wanting to 'catch AIDS'. know he wouldn't have said anything like that if he knew about me. He doesn't think anyone he knows is affected by HIV, so he made that comment without thinking, because he doesn't know any better."
Amelia feels that having to learn to be cautious about what she reveals about herself, has made her more cynical than other people her age.
"People must wonder why I'm so guarded," she muses. "Whenever I start to get close to anyone, it always goes through my mind that one day I'll have to tell them.
It's a scary thought and it means I tend not to get too close to many people, because I feel like unless I can tell them, I'll always have to watch myself around them to make sure I don't let something slip.
It has made her wary of looking for love too.
"It definitely holds me back from starting up romances," she says. "I can't really trust easily. Before I get into a relationship with someone I have to see if that person is trustworthy and try to work out how they would react if they knew.
"It's really hard, because you can't always tell. I've heard stories about people who have told somebody that they thought they could trust, only for them to go and do something that shocks them. You have to be wise."
Amelia didn't confide in a single one of her friends about her HIV status for six years after she was diagnosed, until last year when she was in sixth form. She gained the confidence to talk to them through working with London-based Body & Soul.
Body & Soul offer a safe space for children and teenagers affected by HIV to socialise. They provide 'mentoring' services to help answer any questions the children may have about HIV and they also run creative workshops, such as dance and music sessions.
Amelia has been regularly attending sessions run by Body & Soul since she was 13 and she has recently embarked on an apprenticeship with the charity.
"When I was younger I just wanted an escape, and that's what coming to Body & Soul was for me, an escape. I didn't have to discuss anything I didn't want to, but I also didn't have to hide anything either.
"I mainly enjoyed the music and creative sessions, but I had mentoring too, which helped me to think about my future and I guess I gradually began to learn more about HIV."
Amelia has been closely involved in the charity's latest campaign called Life in my Shoes, which aims to educate young people about HIV and challenge misconceptions through a mixed-media campaign.
As part of the project Amelia helped with the production of a short film called Undefeated – which explores one girl's struggle when her 'secret' is exposed by a secretary at her inner city school.
"New young people came into Body & Soul to work on the film and for me that felt a little bit weird. Body & Soul is like my home, so to have outsiders coming in was difficult," says Amelia.
"But in the end it was good, because it challenged me and made me feel more confident about talking about HIV with people my age."
The confidence Amelia gained through working on the project helped her find the courage to trust some of her closest friends with her secret.
"I finally told two of my friends when we were in Year 12," she explains. "I didn't plan to do it, it just happened naturally. I was working on Life in my Shoes and I was really excited about it. I was telling these friends, who I've known for years, about being on set and then I just thought, you know what? This is the perfect time to tell them.
So then I just told them.
"I also told another friend just yesterday. At first he thought I was joking! He didn't take me seriously until I showed him my medication box.
"But actually all three of the friends I've told have been so open about it and so understanding. I explained that it's not something you can tell everyone because there's so much negative stigma around it, so for me to tell them shows that I really trust them."
Through her work with Body & Soul Amelia wants to help other young people with HIV find the same confidence and acceptance that she has.
"Now I never get too bothered about the negativity surrounding HIV, because it's something that I aim to change. In the future I'd like to be able to run youth groups and talk to more teenagers about living with HIV as a young person."
Click here to watch Undefeated.
*Name changed to protect identity