Brief Answer:
Most likely a viral infection

Detailed Answer:
Hello

Thanks for asking on this platform

Fever,cough and rashes are common presentation of many viral infections. These viral infections are highly contagious.
The common viral infections are Measles, Coxasckie virus, Adenovirus and Enterovirus.
In measles illness usually starts with fever, cough and conjunctival congestion. Rashes develop usually on 4th day of illness and starts from face gradually spreads to other part of body.
In other viral infections conjunctivitis is more prominent and usually there is no gap between the fever and rashes. On clinical finding it is difficult to differentiate between the other three viruses and serology may be needed to identify the organism.
In all these infection only symptomatic treatment is needed and there is no specific treatment.
It usually takes 4-6 days fir the symptoms to subside if there is no further complication.
Other uncommon cause can be scarlet fever (bacterial) but here conjunctivitis is not common.

I hope this helps.
Please let me know if you have any more questions.
Regards

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Brief Answer:
My pleasure

Detailed Answer:
Its my pleasure that you found my answer helpful.I shall be glad to help you out if you need any.
Wishing for her rapid recovery.
Regards

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