The rotating figure of the red, spiked virus aka corona, aka Covid-19, has wasted no time in becoming a worldwide global enemy. Within 2 to 3 months of its existence, it has forced most of the world into quarantine and left economies grinding to a standstill. The virus, which began its deadly course from Wuhan, China is said to have come from bats, and through cross-species mutation jumped to humans, becoming highly infectious and transmissible through respiratory droplets. This contagion is what makes the virus so feared and seemingly unconquerable until now.
Other things that are scary about Covid-19 are that, for one thing, this virus may or may not manifest itself through symptoms, thus making it impossible to trust the next person, and for another, the virus adapts to its environment and mutates. Can this get worse? Yes, it can. For many who are forced to stay indoors, the future does not look promising. There are victims of domestic violence who will most likely lose their lives to violent parents or spouses before COVID can even get a closer look. Suicide cases are on the rise in Bangladesh as daily labourers are forced to stay indoors and look at the hungry faces of their family members before giving in to cloying guilt. Anxiety will likely kill the middle-class workers who live paycheck to paycheck as local and multinational companies cut jobs and freeze pay.
The top tier to isn’t exactly in for a joyride either. The virus is cutting into their savings and the government can only do so much to help key industries keep up during this time. After all, the government too is faced with a difficult choice- save the economy it has so painstakingly created post the 1971 liberation war, or the people who make it up. Food shortages loom as farmers leave their produce to rot in the fields and dairy farmers overturn their cans of milk into the sewers. The pandemic which can kill people in days threatens to pull the world economy back at least 30 years.
It is at this time, however, that doctors and scientists must come to the rescue of the people and come they have. While looking for a vaccine is of topmost urgency, testing methods also take the lead in curbing the spread of this deadly antagonist. As the World Health Organization has advised, the key to slowing down the spread is to test, test and test. Countries that have invested in testing kits and have tested masses are topping the success charts right now. Testing people have eliminated COVID carrier stigma, early detection and treatment have helped people recover, and in the worst case, the higher number of COVID positive people have reduced the death rates of countries, thereby breaking the virus’s omnipotence in the eyes of the masses. People in these countries have stayed mentally strong amid the crisis, whether they were battling it physically or economically.
So then if testing is the key to survival until we wait for the vaccines, how do we know which testing methods are the most important? That’s where we come in. Read on to know some of the most reliable testing methods used around the world.
The NAAT Test
The Nucleic Acid Amplification Test is the most common test being carried out to detect the Covid-19 virus. Samples are collected from the upper respiratory tract, for a mixture of saliva and mucus which is then taken back to specialized labs to be tested. The process uses a real-time reverse transcription-polymerase chain reaction (rRT-PCR) assay. Let’s just say it checks for possible viral contamination for ease of understanding. The testing process is very reliable and takes up to 3 to4 hours. The results can usually be made available within days. The problem with this test, however, is that it is not as widely available.
These tests are used to detect antibodies present in the white blood cells which fight antigens or foreign bodies present in the bloodstream. The John Hopkins University claims that certain antibodies present in our blood serums help fight foreign pathogens when recognized as such by the immune system. Serological tests can help to find out the rate of infection in a community and also the mortality rate. Similarly, the tests can also identify individuals who have built antibodies against the Covid-19 virus and these individuals can then help others in need of such immunity. The test, however, does not make clear whether a person is ailing currently; only that possible infection has been present sometime in the past. While serological tests are not being hailed as game-changers right away, the process of sample collection is as easy as pricking a finger to draw blood and the results can be obtained in 15 minutes. More research is being done on these tests as they are helpful in testing asymptomatic people or in finding out those who may not have been tested in time but have developed antibodies and recovered. This test gives a better idea about the magnitude of the spread in the community which regular respiratory tract tests cannot, due to costs or lack of availability or time.
There are essentially three types of serology assays, which can help, not in case of detection but in aiding research:
Rapid Diagnostic Test: A qualitative (positive/negative) test, much like your regular pregnancy test, this method can be carried to places and conducted using blood samples, salivary samples or nasal swab fluids. The tests mostly test for patient antibodies against the presence of any viral pathogen present in the patient’s blood serum. The results can be given out in as early as 10 to 30 minutes.
Enzyme-linked immunosorbent assay: Mostly quantitative, these are lab-based tests which include taking a patient’s blood, plasma or serum samples. They essentially test for the same antibodies as the test above except that the testing methods are different. None of these tests can tell us the number of antibodies present in the bloodstream or if these can protect the patient from future contamination. The results can be given out in 5 or fewer hours.
Neutralization Assay: This test can tell if antibodies in the blood serum of a patient are active and effective in case of a viral attack, even if the patient has recovered. The tests require whole blood samples, serum or plasma and take 3 to 5 days to give out a solution.
Testing people has eliminated Covid carrier stigma, early detection and treatment has helped people recover, and in the worst case, the higher number of Covid positive people have reduced the death rates of countries, thereby breaking the virus’s omnipotence in the eyes of the masses.
Bangladesh recently gave permission to Ganashastha Kendra to manufacture low-cost testing kits which could be a great solution to problems like a shortage in test kits. The tests come as cheap as $3 and can give out solutions in 15 minutes. They fall under NAAT testing and involve talking nasal swabs as samples. While the only gold standard is the RT-PCR testing kit, rapid dot blot tests like the one in question can be given a shot in countries like Bangladesh where costs and availability make it difficult for testing to happen for the masses. Even now, Bangladesh has one of the lowest testing figures in the world and low-cost testing kits can drastically change the game. Makers of this kit are working day and night to improve the efficiency of the kit at hand. They realize that Bangladesh being a densely populated country would most likely see a surge before a lull in the number of COVID positive cases and in a situation where things can take a drastic downturn, dot blot kit makers are more hopeful about the faster kits than the slower ones, especially with only a 10% margin of error. However, at the moment, such tests are not recommended by WHO fully.
Much remains to be seen as the country is just now beginning to feel the magnitude of the problem at hand, even if they always had an idea of how the situation would be. While WHO continues to recommend testing via NAAT testing methods, isolation and social distancing to flatten the curve, low and middle-income nations wait with bated breath, for green signals to low-cost testing, more research breakthroughs for increasing effectiveness of low-cost tests and finally, a vaccine to finally put an end to this pandemic, once and for all.