New Delhi, July 30 - India's world No.6 Saina Nehwal is down with chicken pox, but she is confident of getting fit in time for the World Badminton Championships in Hyderabad from Aug 10.

Saina said she has been advised rest for four days after which she will be able to take a call on when to start training.

'I saw the doctor yesterday and they said it was chicken pox. I have been advised rest for four days, so there will be a break in my training, which was going well. But hopefully I will recover in time for the tournament,' Saina told IANS Thursday over phone from Hyderabad.

'I was running temperature for last 3-4 days, but today I do not have fever.

'My training will suffer a bit, but I hope I will still get some sessions to hit before the tournament,' she said.