Arsenal captain Pierre-Emerick Aubameyang says he lost four kilos in weight and was “really, really down” after contracting malaria while on international duty with Gabon in March.
Aubameyang, 31, made his return as a substitute in the Europa League semi-final first-leg defeat by Villarreal last week.
“This was the worst moment of being sick in my life because it was really hard,” he said.
“I was feeling very, very bad.”
The forward, who scored in Gabon’s 3-0 win over DR Congo in Africa Cup of Nations qualification on 25 March, said he began to feel unwell during Arsenal’s home loss to Liverpool on 3 April.
“As you know, going to Gabon is not so close to here,” he said. “I felt just a bit tired, especially against Liverpool, but I thought it was just because of the travel.
“I had three days in a row, fever, all day and all night, non-stop. Even the paracetamol and stuff had no effects on this. After that, I spoke to the doctor.
“I said I needed to go to the hospital because I had travelled to Africa so maybe it was something like malaria.
“I stayed in hospital for three days. I was really, really down and I think I lost four kilos. It was a really bad moment and I think my family was a bit scared to see me like this.”
After playing in Arsenal’s Europa League quarter-final first leg against Slavia Prague on 8 April, Aubameyang missed the second leg and three Premier League games for the Gunners.
He was added to the starting line-up to face Newcastle at St James’ Park on Sunday by manager Mikel Arteta, and repaid the Spaniard by grabbing a goal and an assist during the 2-0 win.
Aubameyang believes he is fit enough – physically and mentally – to face Villarreal in the second leg on Thursday and help Arsenal reach the Europa League final in Poland on 26 May.
“I would say I feel 90% – but I feel ready to start the game when it is important like this,” he added “In my mind I feel more than 100%. My body has responded well but in my mind I’m definitely ready.
“It’s been a really tough year because I have had some issues on and off the pitch, but in my mind I’m hungry and I want to finish [the season] off well for the club.”