William had a throat infection. 
William had a viral infection today.
William had a viral headache hence his absence. 
William had a viral headache, hence his absence.
William is recovering from a chest infection –

could he be excused from swimming?
William seems to have lost his music book –

could the boys check?
William had a viral headache hence his absence
William unfortunately caught

a nasty viral bronchitis
William had a viral bronchitis.
William is unable to swim,

due to a lingering

               “gastroenteric

                              germ” 
William is to be excused from swimming –

he is still harbouring his virus
William had acute gastroenteritis 
William had a throat infection, hence his absence. 
William has recovered from the chicken pox,

but will be picked up at lunch time, i.e.
no sport