Hello,
Thanks for posting your query.
A temperature of 36 ° C should be considered the lowest limit of normal and is definitely a cause of concern in a 6 weeks old infant. Any further fall can put him at risk of developing hypothermia.
Hypothermia, a potentially fatal condition, occurs when body temperature falls below 95°F (35°C).
The causes in your child could be an unresolved respiratory infection, superadded bacterial infection, septicaemia ( an infection is present in the blood streams) or inadequate hydration and malnutrition.
In our child’s case, it is more likely that it is an either bacterial or unresolved viral infection. This warrants early intervention like a thorough clinical examination and investigations like X rays, blood counts, etc to confirm the diagnosis.
The less likely possibility of dehydration can be ruled out by increasing the frequency of breastfeeding (or formula feed if not breastfed) to say 1-2 hourly, keeping the baby warm, and providing symptomatic relief for cough and cold as prescribed.
However, if his temperature remains subnormal or worsens and in case there are new symptoms like fast breathing, wheezing, lethargy or irritability and excessive cry then, inspite of the above treatment, it is best to take the child for an emergency consultation to rule out septicemia, pneumonitis or such serious cause.
If your baby is accepting feeds, passing urine and stool normally, and colour improves with temperature and hydration you can wait for a routine follow up appointment with the pediatrician.
Another point to confirm is to repeat the temperature recording (preferably by a trained person and take a rectal temperature measurement) , after a few hours to avoid confusion.
As of now, the situation needs evaluation before an exact cause can be identified.
I hope I have answered your query.
Regards

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