• Published on: Jul 09, 2020
  • 2 minute read
  • By: Dr Rakesh Choudhary

COVID- 19 Tests – What Do You Need To Know?

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COVID- 19 tests – What do you need to know?

Author: Dr. Rakesh Choudhary MBBS, MS, FRCS UK, FRCS Orth UK, MChOrth UK.

 Dr. Choudhary is a practicing consultant surgeon in the UK.

So many of us think it is not their job to learn about COVID-19 tests and this should be left for the experts and governments to decide about these tests. But I strongly suggest the public must have a basic understanding of these tests which they may have to have themselves.

Basically there are two types of tests, one which can detect the virus in the body and the other one which tells if the person had the previous infection.

Virus test

The virus test detects an active infection. It detects the genetic material (RNA) of the virus during an active infection. It is also called a PCR (polymerase chain reaction) test or nucleic acid test and is sometimes inaccurately called an antigen test.

 A swab is taken from deep in the back of your throat and deep in the nose. The swab should go deep up to 7-8 cm and is generally uncomfortable for the patient. Swabbing patients using the correct technique is paramount in ensuring an accurate result. By simply swabbing the inside of the nasal passage is not deep enough to verify that the virus is present.

What does virus testing tell you?

This test tells us if a patient is actively infected with the COVID-19 virus. Virus testing is used mainly for the diagnosis of COVID-19.

When should it be done?

The virus test works best during the first seven days of symptoms.

The coronavirus can be detected in  swabs even before symptoms of illness first appear . This is why people can be infectious for a few days before the onset of symptoms, which usually appear about 5 days after the virus infects. Some people have no symptoms throughout their infection but are positive on the virus test and infectious to others. After a few days of illness, the concentration of the virus falls (as seen in swab samples) and the symptoms of the illness usually recede. 

Accuracy of the test

In a person with COVID-19, the test is less likely to give a positive result late in the course of infection once the virus has been cleared by the immune system, or if an inadequate sample is taken from the nose or throat. There are concerns that the rate of ‘false negative’ test results could be as high as 30% and a significant number of people are wrongly being told they do not have the virus.

Antibody test

Antibody tests check your blood by looking for antibodies, which may tell you if you had a past infection with the virus that causes COVID-19. Antibodies are protein structures that are produced by the immune system in response to certain infections. The antibody can help fight off infections and can provide protection against getting that disease again (immunity). Antibodies are disease-specific. For example, measles antibodies will protect you from getting measles if you are exposed to it.

The antibody test detects the presence of antibodies as a marker of past infection. The antibody test (blood test) will only detect infections after the immune system has produced antibodies that recognize the virus. This happens approximately 7–10 days after symptoms develop.

Tests carried out a week after a patient develops symptoms will detect only 30% of people who had COVID-19 infection. Accuracy increases to 72% at two weeks and to 94% in the third week. Some people may take even longer to develop antibodies, and some people who are infected may not ever develop antibodies.

Interpretation of the antibody test is complex for non-medical people. Basically having antibodies to the virus that causes COVID-19 may provide protection from getting infected with the virus again. If it does, we do not know how much protection the antibodies may provide or how long this protection may last.

Read Blog
Fatigue

why fatigue should not be ignored

Feeling tired occasionally is a normal response to physical exertion, lack of sleep or emotional stress. However, when fatigue becomes persistent, overwhelming or unexplained, it should not be dismissed. Fatigue is one of the most common symptoms reported in healthcare, yet it is also one of the most frequently ignored.

Understanding why fatigue should not be ignored is essential because it often acts as an early warning sign of deeper physical or mental health issues.

 

What Is Fatigue?

Fatigue is a state of ongoing physical, mental or emotional exhaustion that:

  • lasts longer than expected
     

  • interferes with daily activities
     

  • does not improve with rest or sleep
     

Unlike ordinary tiredness, fatigue affects motivation, concentration and overall functioning.

 

Why Fatigue Is Commonly Ignored

Fatigue is often dismissed because:

  • busy lifestyles normalise exhaustion
     

  • symptoms develop gradually
     

  • people attribute fatigue to stress or ageing
     

  • rest temporarily masks the issue
     

Ignoring fatigue allows underlying conditions to progress unnoticed.

 

Common Medical Causes of Persistent Fatigue

Nutritional Deficiencies

Deficiencies in:

  • iron
     

  • vitamin B12
     

  • vitamin D
     

  • magnesium
     

can significantly reduce energy levels and cause weakness.

 

Anaemia

Anaemia reduces oxygen delivery to tissues, leading to:

  • constant tiredness
     

  • breathlessness
     

  • dizziness
     

It is one of the most common yet underdiagnosed causes of fatigue.

 

Thyroid Disorders

Both underactive and overactive thyroid conditions affect metabolism.

Symptoms include:

  • fatigue
     

  • weight changes
     

  • cold or heat intolerance
     

Thyroid-related fatigue often persists despite rest.

 

Chronic Infections

Low-grade or unresolved infections keep the immune system activated, causing prolonged fatigue.

 

Hormonal Imbalance

Hormones regulate energy, sleep and metabolism.

Imbalance may lead to:

  • exhaustion
     

  • poor sleep
     

  • low motivation
     

 

Poor Sleep Quality

Even with sufficient sleep duration, poor sleep quality can cause fatigue due to:

  • sleep apnea
     

  • frequent awakenings
     

  • stress-related insomnia
     

 

Mental Health Conditions

Anxiety, depression and chronic stress commonly present with fatigue as a primary symptom.

Mental fatigue is as real and impactful as physical fatigue.

 

Lifestyle Factors That Worsen Fatigue

Certain habits intensify tiredness:

  • irregular meals
     

  • excessive caffeine
     

  • dehydration
     

  • lack of physical activity
     

  • prolonged screen use
     

Lifestyle-related fatigue often coexists with medical causes.

 

How Fatigue Affects Daily Life

Persistent fatigue impacts:

  • work performance
     

  • concentration and memory
     

  • emotional regulation
     

  • physical activity
     

  • social relationships
     

Over time, quality of life declines significantly.

 

Warning Signs That Fatigue Needs Medical Attention

Seek evaluation if fatigue:

  • lasts more than two weeks
     

  • worsens progressively
     

  • occurs with weight loss or fever
     

  • is associated with breathlessness
     

  • interferes with daily tasks
     

These signs suggest an underlying issue.

 

Why Early Evaluation Matters

Early identification of fatigue causes:

  • prevents disease progression
     

  • simplifies treatment
     

  • improves recovery time
     

  • restores normal energy levels
     

Delayed care often leads to chronic complications.

 

Diagnostic Evaluation for Fatigue

Assessment may include:

  • detailed history
     

  • blood tests
     

  • nutritional screening
     

  • hormonal evaluation
     

  • sleep assessment
     

Testing helps identify root causes rather than treating symptoms alone.

 

Can Fatigue Be Prevented?

Some preventive measures include:

  • balanced nutrition
     

  • adequate hydration
     

  • regular physical activity
     

  • consistent sleep routine
     

  • stress management
     

However, prevention does not replace evaluation when fatigue persists.

 

Fatigue and Chronic Disease Risk

Long-term fatigue may be linked to:

  • cardiovascular disease
     

  • metabolic disorders
     

  • immune dysfunction
     

This makes fatigue an important early health signal.

 

When Rest Is Not Enough

If energy does not return after:

  • adequate sleep
     

  • reduced workload
     

  • lifestyle changes
     

medical evaluation is essential.

 

The Cost of Ignoring Fatigue

Ignoring fatigue can lead to:

  • delayed diagnosis
     

  • worsening health conditions
     

  • reduced productivity
     

  • emotional burnout
     

Listening to the body early prevents long-term consequences.

 

Conclusion

Fatigue is not merely a sign of a busy life—it is often the body’s way of signalling imbalance or illness. Persistent tiredness that does not improve with rest should never be ignored. Whether caused by nutritional deficiencies, hormonal changes, chronic stress or underlying disease, fatigue deserves attention. Early evaluation and timely care can restore energy, prevent complications and significantly improve quality of life. Listening to fatigue is an act of self-care and preventive health.

 

References

  • Indian Council of Medical Research (ICMR) – Fatigue and Lifestyle Health Report

  •  World Health Organization (WHO) – Chronic Fatigue and Health Guidelines

  •  National Institute of Nutrition (NIN) – Nutrient Deficiency and Energy Research

  • Lancet – Fatigue as a Marker of Chronic Disease Studie

  •  Indian Journal of Medicine – Persistent Fatigue and Diagnosis

  • Statista – Fatigue, Stress and Health Trend Analysis

See all

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