The 26-year-old made the last of her four appearances for Chelsea this season as a substitute in November's 1-0 win over Manchester United after missing the start of the campaign because of injury.Following that game Kirby was diagnosed with pericarditis, a condition which is uncommon in athletes and refers to inflammation of the pericardium (the fluid-filled sac that surrounds your heart). Normally it is caused by a viral infection and manifests with symptoms typically including sudden onset of sharp chest pain, fever, nausea, shortness of breath and weakness.Those who contract pericarditis can recover quickly but for others – including our England international – it can take months with Kirby revealing she was sleeping 15 hours a day during the early stages of the illness and taking anti-inflammatory medication following the diagnosis.Kirby is yet to return to training but is back with the squad at Cobham on a day-to-day basis and preparing to reintegrate herself into the team.Speaking about the last few months she said: ‘I am feeling 100 times better compared to when this started. I was struggling with understanding how it happened and why it happened as I was feeling good with no injuries and enjoying training with the team so it was frustrating at the time.‘When I became ill the frustration went away as I didn’t even have the energy to be frustrated, I had no emotion as I was too tired. It took over my life in a negative way, I couldn’t even get up to make food.

‘Now that I am feeling more like a human being I can smile again and be in a room with people again. Before when people were having conversations with me I couldn’t acknowledge them I was just sitting there thinking ‘I am so ill, I am so ill’, it was just constantly on my mind.

‘Now I am coming to the other end of it, I am back around the girls more, I have the energy to come in or go to the pool when they are doing recovery.

‘I want to be back on the pitch more than anyone! I also know it will take time and I am not going to heal overnight and it is a day-by-day process.

‘I know how ill I was and I don’t want to go back to that, I want to make sure when I come back I am 100 per cent with no symptoms and I am ready to go.

‘I am getting there, I have more energy and less symptoms but I need to go slowly as if I come back to soon it could be another three weeks out.

‘There is lots to look forward to at Chelsea and for England and I am on the road to recovery. There are important games coming up and I am really hopeful I can be back to take part in them.

‘I also want to thank everyone who has supported me during this time. From the doctor at Chelsea who made sure I had everything I needed to recover, to Emma, the staff, the players and those in my support network. It meant so much to me to be surrounded by so many people who cared about me.’

For manager Emma Hayes it has been difficult to see one of her players struggling but getting Kirby healthy and back to her best is all that matters, regardless of how long it may take.

‘Fran is a massively important part of our squad and she knows that, but while winning football matches is important, it is not more important than her health,’ she said.

‘Good health is the priority in our culture, and her good health matters above and beyond anything else.

‘Our job, when she is ready, is to make sure she comes back at even higher level than before.

‘I can also assure the fans they will see a lot more of Fran Kirby playing and scoring goals for Chelsea.’

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