What is the test for coronavirus and how does it work?

The outbreak of a novel coronavirus (COVID-19), originating in China's Hubei province, has set alarm bells ringing across the world with cases of the infection confirmed in over 50 countries.

Reports on the virus, which has sickened tens of thousands of people and killed more than 3,000 globally, are nearly ubiquitous on social media and news bulletins, triggering widespread panic among ordinary citizens.

So what happens if you have a fever, cough and experience breathing difficulties? You might even go to a hospital with symptoms of pneumonia leading doctors to fear that you may have contracted the virus.

But how can you know with certainty if you've really been infected with the novel coronavirus?

Ideally, you will get yourself tested for the virus for confirmation. But what is the test for the virus and how is it conducted?

IEDCR HOTLINE

The IEDCR has opened a service for the public to report suspected coronavirus cases. Any person showing symptoms of COVID-19 and suspected to have contracted the coronavirus is requested to call IEDCR hotline numbers:

01927711784,  01927711785,  01937000011,  01937110011

THROAT SWAB

Testing for COVID-19 is rather similar to that for the flu. First, a specimen will be collected to check for the virus.

Health experts believe the coronavirus replicates in the respiratory tract, causing mild to moderate upper-respiratory tract illnesses, like the common cold.

The World Health Organization (WHO) and the US Centres for Disease Control (CDC) therefore recommend deep throat swabs, going through both your mouth and your nose. You may also be asked to cough up sputum, a mixture of saliva and mucus.

This procedure is being followed by specialists at the Bangladesh government's disease control agency, the Institute of Epidemiology, Disease Control and Research or IEDCR.

The ultrastructural morphology exhibited by the 2019 Novel Coronavirus (2019-nCoV) is seen in an illustration released by the Centres for Disease Control and Prevention (CDC) in Atlanta, Georgia, US January 29, 2020. CDC via REUTERS

Unlike other diseases, testing for the novel coronavirus doesn't require the collection of blood, stool or urine samples, Dr ASM Alamgir, principal scientific officer of IEDCR's Department of Medical Entomology, told bdnews24.com.

"We collect a sample of the potential patient's saliva or mucus from the nose. An examination of such a sample reveals if there is a coronavirus infection."

THE SPECIMEN WILL BE SENT TO A QUALIFIED LAB

According to a report by CNN, citing the US testing procedure, once a sample has been collected, it must be stored in a sterile tube or vial as is the case with any other medical test.

In order to preserve the specimen, it is first chilled before being shipped with an ice pack to a qualified lab with access to a coronavirus test kit. In Bangladesh, only the IEDCR has the facilities to conduct such a test.

Laboratories are required to have a minimum biosafety level or BSL of 2 to run tests for Nipah or Influenza virus, said Alamgir. The IEDCR is equipped with both BSL-2 and BSL-3 facilities.

"Only one or two medical colleges in Bangladesh have such labs. But they don't have the capacity to conduct tests for the coronavirus. Even though they have the labs, they don't have an entomologist or a rapid response team," said Alamgir.

RT-PCR TEST

Once samples arrive at the lab, technicians use a procedure called RT-PCR, or reverse transcriptase polymerase chain reaction, to look for the genetic code of the coronavirus using a special reagent.

In the US, the CDC has developed a new laboratory test kit for use in testing patient specimens for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes COVID-19.

The test kit is called the “Centers for Disease Control and Prevention (CDC) 2019-Novel Coronavirus (2019-nCoV) Real-Time Reverse Transcriptase (RT)-PCR Diagnostic Panel".

The IEDCR is using test kits provided by the WHO called "PCR Primary Probe Reagent", according to Alamgir.

A virus, just like any other species, has a unique genetic code called the viral genome. This code, called the viral genome, provides the blueprint for the virus as it replicates and the coronavirus test works by determining whether any given specimen contains the distinct coronavirus genome, according to the CNN report.

Lab technicians first extract any genetic information from the throat swabs and sputum samples. The purified genetic material is then mixed with a set of ingredients, including some derived from the coronavirus itself, and the entire solution is placed into a testing machine, the report adds.

The virus' genetic material will amplify if a patient's specimen contains the coronavirus and the machine will return a positive result. The IEDCR will send the specimen to the WHO which will then run a test to confirm the result.

HOW LONG WILL THE TEST TAKE?

According to Alamgir, it takes the IEDCR at least three hours to return a result for the test.

"A number of procedures have to be followed after the sample is brought in. First we have to extract the RNA before running it through the PCR machine. There are a few other steps after that so it takes us about three hours to complete the test."

But the entire process is dependent on receiving a sample. Each RT-PCR test costs more than Tk 5,000 but the government is currently bearing the expenses.

ARE THERE ENOUGH TESTING KITS?

At present, the IEDCR has about 1,500 test kits with more on the way, according to Alamgir.

On whether these will be sufficient if the virus spreads in Bangladesh, he said that it won't be necessary to run tests on every potential patient should such a scenario transpire.

"We have surveillance measures in place throughout the country. So if anyone tests positive for the coronavirus, we will ask hospitals across the land to send the samples of every patient suffering from a cold or breathing trouble."

"If any of the samples test positive for coronavirus, then we will know that the virus has begun spreading in the country. This is called community transmission."

In such a case, hospitals will be directed to treat people with symptoms of the infections as coronavirus patients, said Alamgir.

WHAT IS THE TREATMENT FOR CORONAVIRUS?

Much like the common cold or flu, the coronavirus infection doesn't have any special treatment. Since a vaccine for the virus is yet to be developed, the only way to stay safe is by avoiding close contact with infected people.

As there is currently no treatment or cure for the infection, hospitals in the UK are trying to relieve the symptoms while allowing the patient's immune system to fight the virus, according to the BBC.

Patients with pneumonia are generally given oxygen and in the worst cases, they may be put on a ventilator.

A strong immune system can help fight the virus naturally within a few days.

According to the WHO, older persons and persons with pre-existing medical conditions (such as high blood pressure, heart disease, lung disease, cancer or diabetes) appear to develop serious illness more often than others.