As a Commonwealth English speaker, I am not aware of a rule preventing contraction of the possessive verb "to have." Maybe there is, and I'd be interested to le

As a Commonwealth English speaker, I am not aware of a rule preventing contraction of the possessive verb "to have." Maybe there is, and I'd be interested to learn about it. Having said that, commonly I wouldn't say, "I've a case of bronchitis," rather just "I've bronchitis." It feels more natural to say "I have a case of bronchitis." However, this may just be personal preference.