Brief Answer:
Chest physician's advise & home care would help.

Detailed Answer:
Hi XXXX,
Thanks for the query on Health care magic platform.I have read it & understand your concern.
Actually, The infection of Mononucleosis mostly does not recur, though the virus causing Mono ( Epstein Barr virus) remains in patient's body in dormant form, all the life. It may get activated some time & then it can be found in saliva, BUT the person does not get symptoms any more except when he has weak immune system( like AIDs) ...
Now about your grandson's recent infection causing severe cough. This can be due to bacterial infections following weakness after mono.
The high fever & no reduction in his trouble indicate the antibiotic being given to be not effective.
In this context I would advise for consultation of a chest specialist for extensive physical examination, Investigations ( like CBC/ Sputum culture & sensitivity/ Allergy screen test/X ray chest, as per need) to know about the severity of infection, sensitive antibiotic, & state of his overall health & immunity . This would be followed by specific antibiotic & other helpful drugs like anti allergic pills, steroids, cough mixtures as per need...
* Home care-
- he should have light,nutritious diet avoiding oily, spicy , allergens - if any
& cold or sour eatables.Drink warm water.
- Warm saline water gargles would help. Inhaling vapor in case there is
nasal congestion
- Avoid exposure to cold, dust or smoke.
-Take rest with a propped up position( High head end with slanting body
position with pillows under head)
* Thus with expert advise & specific treatment along with home care he would be fine in few days. Please don't worry.
I hope that answers your query. Any follow up query is welcome.
Please close the answer if you don't have any follow up query.
Thanks.

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