It is a problem that has caused him to miss games for Liverpool as well, and he admits: "It is not just simple flu, it is tonsilitis. Most people get their tonsils out when they are younger but I have really suffered badly over the last couple of years so I am looking at the possibility of having my tonsils out soon.
"It is one of those things, and I spent a couple of days in bed over the weekend without food, just drinking water and taking tablets.
"I have trained and felt all right so hopefully I can get on at some stage at Cardiff."
Neil was unlucky not to get off the mark for West Ham against Reading recently, and he says: "It was just one of those days and I was absolutely gutted. I have to start putting it in and there is no point looking for excuses all the time because at the end of the day you get judged on your goals and I have not scored any so far.
"I have got confidence in my own ability and I am sure it is going to come good soon - I am not worried at all.
"Jermain and Conners have done really well with a few goals so you can't expect the side to change the forward line if they are both firing on all cylinders."
The fact that Neil hasn't started every game when he has been fit gives lie to the theory that he must start every match when he is as a condition of his loan transfer for the season.
"I don't know who said that. No player in the country gets that written into their contract, do they?" he insists.
"Let's be honest, I don't think Beckham would have that in his contract at Real Madrid - you get picked on your ability and at the moment those two are playing better, which is why they are getting picked ahead of me.
"But hopefully I will put them under pressure and I just can't wait to get my first goal; when I do that I will be really happy."
Neil was disappointed not to be able to play his part at Gillingham - a game that would have suited his robust physique - and he adds: "I was really disappointed that we didn't sneak something. I knew it would be a physical game and when they got one I just thought to myself I might have been on the bench with the possibility of coming on to get one back.
"I would certainly have given my best against one of the more physical sides in the division."