Coronavirus Testing – How to Test for Coronavirus? – Different Types of Tests

A lot has been discussed about the recent outbreak of Coronavirus. Since there is a lot of misinformation and rumours doing the rounds, it’s easy to get confused. In this blog, we aim to clear all the myths and present you with accurate information. 

So let’s start by knowing more about the virus first. 

What is Coronavirus?

Coronavirus is a larger family of viruses that cause illnesses such as the common cold, severe acute respiratory syndrome (SARS), and the Middle East respiratory syndrome (MERS). A new outbreak of the coronavirus erupted in 2019 in China. 

Some other names attributed to the coronavirus are severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and coronavirus disease 2019 (COVID-19). 

Coronavirus affects both animals and humans. There can be cases where the virus affects animals and turns into a new virus that affects humans. These are more lethal forms of coronavirus since they can lead to pneumonia, which can be life-threatening. 

The three most common illnesses by the virus recorded are: 

• SARS (severe acute respiratory syndrome) – It’s a fatal respiratory illness discovered in China in 2002. There haven’t been any new cases reported under this virus since 2002. 
• MERS (Middle East respiratory syndrome) – This severe respiratory illness was first reported in Saudi Arabia in 2012. From there, it spread to 27 countries including the USA, where two cases were reported. All cases were discovered to have their source in the Arabian Peninsula. 
• COVID-19 (coronavirus disease 2019) – Erupting in Wuhan city in 2019, the source is travel from the Hubei Province. Since then, the disease has spread to several countries around the world, with some cases reported in the USA. All updates with regards to the disease are being monitored by the Centers for Disease Control (CDC) and the World Health Organization (WHO).

What are the symptoms of Coronavirus?

The symptoms of coronavirus arise when you’ve travelled to the areas of the outbreak of the virus or have been in contact with anyone travelling from those areas. 

The symptoms of coronavirus infections in general are: 

• Fever
• Cough
• Shortness of breath
• Sore throat
• Headache

The specific symptoms of COVID-19 are: 

• Fever
• Cough
• Shortness of breath

The symptoms of COVID-19 are milder than the ones of SARS and MERS. In case you haven’t travelled to these areas or had contact with anyone from these areas, then the symptoms may just be of another virus like the flu. 

Risks of Asymptomatic Transmission

Testing and social isolation is our biggest tool to fight the pandemic. It is the only way to reduce the spread and the impact of the virus. But the asymptomatic transmission of SARS-CoV-2 has made controlling the spread of the disease all the more difficult. The rapid spread of the COVID-19 across the globe is clear evidence of the transmission from asymptomatic persons. 

An asymptomatic person is the one infected with COVID-19 but does not develop any related symptoms. Asymptomatic transmission refers to the transmission of the disease from a person who does not show any symptoms. As per the Union Health Ministry, India, 80 per cent of the COVID-19 cases are either asymptomatic or with mild symptoms. COVID-19 can spread from asymptomatic persons only during the early stages of the disease. There is a possibility to catch COVID-19 from someone who does not feel ill, does not show any major symptoms or has just a mild cough.

Hence at this stage, it is essential to stay indoors and reduce all possible risks of spreading the virus even if you are asymptomatic. Sanitizing everyday objects that may pose a high risk such as mobile phones, food parcels, newspapers and reducing contact with possible hotspots such as elevator buttons, doorknobs, railings, gym equipment is necessary to reduce the chance of spread. It is essential to note that even though it may be asymptomatic for you, it can be fatal for those with compromised immunity due to advanced age or those with underlying conditions such as Diabetes, Asthma, Cholesterol or autoimmune conditions. 

Patient screening and triage:

Patients who present with fever and respiratory symptoms with an epidemiological link to COVID-19 should carry a high index of suspicion for the disease. The epidemiological link may involve (a) travel to an area that experienced an outbreak, (b) close contact with an individual with a confirmed or high risk of infection, or (c) close contact with an individual with respiratory symptoms who had been in a geographic location that witnessed an outbreak within a 14-day period prior to the onset of symptoms. As the geographic area of involvement is expanding, clinicians need to keep themselves updated on the list of affected countries and territories. Following several generations of spread with a country, local transmission of disease occurs, and patients may present with no history of travel to a location with a known outbreak.

Critically ill patients may present to the emergency department from the community or by inter-hospital transfer to the intensive care unit. In such instances, a detailed inquiry should be carried out to ensure appropriate screening and infection control precautions should be followed.

How to get tested for Coronavirus?

In case you feel your symptoms are specific to the coronavirus, your healthcare provider can get in touch with CDC or the local healthcare departments for testing instructions. There are specific labs set up for conducting coronavirus tests, so you may be directed to one of these labs. 

There are different types of coronavirus tests that can be done: 

• Swab Test – In this case, a special swab is used to take a sample from your nose or throat
• Nasal aspirate – In this case, a saline solution will be injected into your nose and, then a sample is taken with a light suction
• Tracheal aspirate – In this case, a thin tube with a torch, also known as a bronchoscope, is put into your mouth to reach your lungs from where a sample is collected. 
• Sputum Test – Sputum is thick mucus that gets accumulated in the lungs and comes out with a cough. During this test, you’re required to cough up sputum in a special cup or a swab is used to take a sample from your nose. 
• Blood test – In this case, a blood sample is taken from a vein in the arm. 

Rapid diagnostic tests based on antigen detection

A rapid test has also been started for the COVID-19, which involves taking samples from the nose, throat, and lungs. A rapid diagnostic test (RDT) of a sample of the respiratory tract of a person helps to detect the viral proteins (antigens) related to the COVID-19 virus. This ensures a speedy and accurate diagnosis and its usage is CDC-approved. 

Rapid diagnostic tests based on host antibody detection

This test detects the presence of antibodies in the blood of COVID-19 infected people. The strength of antibody response depends on several factors like age, medications, infections, and severity of disease etc.

Before the test, the concerned health professionals may request you to wear a mask during the test. In case there are any other steps that need to be taken, the healthcare professional can communicate that to you. 

What are the risks associated while testing for Coronavirus?

During the test, you may feel a gagging sensation when the swab will be inserted into your nose and throat. The nasal aspirate may especially seem a bit uncomfortable. However, all of these effects are temporary and will go away shortly after the test. In some cases of tracheal aspirate, there may be bleeding or infection. In the case of the blood test, no risks are observed. There may be a slight swell and pain in the area where the needle was inserted, however it goes away pretty soon. 

What next if the Coronavirus test comes positive?

In case your test results come out positive, then you may be affected by the coronavirus. Although there are no specific treatments for the coronavirus infection, however, the healthcare professional may suggest some steps that’ll help you to relieve the symptoms. 

Some of the steps you can follow to ease the symptoms are: 

• Drinking a lot of fluids
• Getting plenty of rest
• Taking over-the-counter medicines

In case your condition gets worse or you show signs of pneumonia, you should get admitted to a hospital. Some of the common symptoms of pneumonia are severe cough, laboured breathing, and high fever. 

If you’re diagnosed with coronavirus, you should follow the below steps to prevent any spread of infection: 

• Don’t leave home unless to get medical help
• Always wear a face mask in public places or when you’re around other people
• Don’t share any personal items such as drinking cups, eating plates, towels, or any other items with anybody. 
• Always wash your hand thoroughly for around 20 seconds. In case soap water is not available, you can use an alcohol-based sanitiser, which at least contains 60% alcohol. 

In case your results turned negative, you can check with the healthcare professional whether any further tests are required. It’s better to take precautions to not prevent the infection any further. 

On the other hand, you can avoid getting infected by coronavirus by following the below steps: 

• Wash your hands thoroughly for 20 seconds and use alcohol-based sanitisers in absence of soap-water
• Avoid touching your eyes, nose, or mouth a lot 
• If possible, avoid being close to people who are sneezing or coughing
• Clean the household items which are frequently handled with a disinfectant spray

When to seek medical care?

In case of minor symptoms such as mild fever or cough, there is no need to visit your doctor. Monitor your symptoms, self-isolate and stay at home. If you are living in any of the COVID-19 hotspot areas, then do not ignore the symptoms of fever if it exists beyond three days. Seek medical help immediately. In any case, always wear a mask while stepping outside or visiting a doctor. Keep a distance of 6 feet from other people and do not touch surfaces with your hands. Seek medical help if you have difficulty breathing or pain and pressure in the chest.

Dr. Harish MM, Consultant Anaesthesia & Critical Care, Mazumdar Shaw Medical Center, Bommasandra, Bangalore