Why Temperature Monitoring Matters: From Fever Detection to Long-Term Health Insights

At INS LifeGuard, we believe in the power of proactive health monitoring. Body temperature is one of the body’s vital signs, and fluctuations can provide early warning of illness, infection, or underlying health changes. With new wearable technology, like wrist temperature tracking available through Apple Health-compatible Apple watches, combined with nurse oversight through the INS LifeGuardian® app, Australians now have more ways than ever to keep an eye on this important health measure.



What is Body Temperature and Why Do We Measure It?

Body temperature reflects how well the body can generate and release heat. Measuring it helps detect changes in health that may require rest, medical care, or emergency intervention.

• Normal ranges: Adults typically sit between 36.5–37.5°C (97.7–99.5°F).
  
• Fever: A temperature of 38°C (100.4°F) or higher usually indicates fever.
• Low temperature: Below 36°C can be a concern, particularly in seniors, infants, or those exposed to cold.

How Body Temperature is Measured

Note that readings can differ depending on the method:

• Rectal temperatures: ~1ºC higher than oral readings
• Tympanic (ear): 0.3–0.6°C higher
• Axillary (underarm): ~1ºC lower
• Forehead (infrared): 0.3–0.6°C lower

Understanding this helps ensure readings are interpreted correctly.

Why Temperatures Change

A person’s temperature can fluctuate for many reasons, including:

• Age – Seniors may struggle to conserve heat; babies have less effective regulation, so ranges vary more widely.
  
• Menstrual cycle – Hormonal changes cause rises during ovulation.
  
• Time of day – Lowest at dawn, highest in late afternoon.
  
• Physical activity – Exercise generates extra heat.
  
• Food and fluids – Digestion can raise body temperature slightly.
  
• Stress – Triggers adrenaline, which can elevate temperature.
  
• Pregnancy – Increased metabolism and hormones raise baseline readings.

When to Check Temperature

• If someone seems unwell (fatigue, chills, sweating, irritability).
  
• When an infection is suspected.
  
• After exposure to extreme heat or cold.
  
• In chronic conditions where fever is a common complication.

When caring for vulnerable groups (infants, elderly, immunocompromised).



Temperature Across the Ages

Babies (0–3 months)

• Any fever ≥ 38°C is a medical emergency.
  
• Go to the nearest emergency department immediately.



Children

• Normal: 36.5–38°C.
  
• Fever > 39°C or fever with other symptoms (stiff neck, rash, dehydration, difficulty breathing) requires urgent care.
  
  

Adolescents

• Same fever thresholds as children.
• Consider lifestyle factors like stress, hormones, and activity when interpreting readings.



Adults

• Fever ≥ 38°C is concerning, especially with symptoms such as chest pain, breathing issues, or persistent headache.
  
• Persistent fever > 3 days needs a doctor’s review.

Seniors

• More vulnerable to both high and low temperatures.
  
• Infections may cause only a slight temperature rise, even a mild fever should be taken seriously.