The world is going through a difficult phase right now. At the same time, it is heartening to see how people from different walks of life are coming together to do their bit in making things better. While the front-line workers are working tirelessly in protecting the world around from this deadly virus, scientists and researchers are burning the midnight oil to understand the virus, its changing nature, patterns to find preventive measures, and cures.

In our latest INDIAai Conversations, Jibu Elias, INDIAai's Content Lead, got into a productive discussion with two leading academicians Dr. Sushmita Mitra and Dr. Nilanjan Saha. The conversation also had Dr. Sanhita Basu who has been working around screening COVID-19 using chest X-ray with the help of deep learning.

Dr. Sushmita Mitra is a professor at the Machine Intelligence Unit (MIU), Indian Statistical Institute, Kolkata. From 1992 to 1994, she was in the RWTH, Aachen, Germany, as a DAAD Fellow. She was a Visiting Professor in the Computer Science Departments of the University of Alberta, Edmonton, Canada; Meiji University, Japan; and Aalborg University Esbjerg, Denmark. Dr. Mitra received the National Talent Search Scholarship (1978-1983) from NCERT, India, the University Gold Medal in 1988, the IEEE TNN Outstanding Paper Award in 1994 for her pioneering work in neuro-fuzzy computing, the CIMPA-INRIA-UNESCO Fellowship in 1996, and Fulbright-Nehru Senior Research Fellowship in 2018-2020. She was the INAE Chair Professor during 2018-2020. Dr. Mitra has been awarded the prestigious J. C. Bose National Fellowship, 2021.

Dr. Nilanjan Saha is an expert in Translational & Clinical Research, New product evaluations, therapy, and ethical marketing. He is also an active proponent of Antibiotic Stewardship. In the past, he volunteered studies with generic and NCEs; Phase I to III clinical trials with anti-cancer and anti-malarial NCEs. He has a significant role in clinical development strategies for new Pharmaceutical products. Dr. Saha has been awarded the Certificate of Appreciation by Former President of India Hon'ble Dr. APJ Abdul Kalam for his exceptional contribution to the development of Synriam, a new age cure for malaria.

Dr. Mitra's idea of using X-rays for screening is based on making the screening more affordable instead of CT scans that are expensive. During the process, they could understand that Pneumonia and COVID-19 had similar representation, which could further be made clear in a CT scan. There were two datasets used, one was from NIH Chest X-ray, and the other was acquired from four open-source databases- Italian Society of Medical Radiology and Intervention (25 cases), radiopaedia.org (20 Cases), J. Paul Cohen et al.COVID-19 image data collection (180 Cases), a hospital in Spain (80 Cases). The data was segregated into data set A- training and validation data with the numbers of normal and diseased cases. The data set B contained the number of normal cases, pneumonia, other diseases, and COVID-19. 

The DETL (Domain Extension transfer learning) algorithm was used in the study. The involved CNN models were trained from scratch on data set A to learn to classify between diseased and normal X-ray images. The next phase was to replace the last fully-connected layer of the pre-trained CNN with a new fully-connected layer, having as many neutrons as the number of classes, which in this case was 4, ie, normal, other diseases, pneumonia, and COVID-19. The rest of the weights in the remaining layers of the pre-trained network are to be retained. Then the last convolution block and the fully connected layers are retrained using SGD (Stochastic Gradient Descent).

According to Dr. Sushmita Mitra, one of the biggest challenges that she faced during this research was that of data. She further added that the new information is coming in with the second wave and changing strains of the virus, which might hamper the algoriths' functioning. She believes that more data from the medical fraternity and more collaborations might act as a rescue and clear out the bottlenecks.

Giving a medical perspective, Dr. Nilanjan Saha added, "The virus is new and we know very little about it." He also explained the difference between viral pneumonia and COVID-19, which is critical in formulating strategies to combat it. He explained that the cost associated with the CT scans and their availability in rural areas is a constraint, and hence for a country as populous as us the X-ray screening is a great idea.

On being asked by Jibu about the challenges faced in obtaining the data and the variation in the strain in the second wave, Dr. Mitra said, "There is a difference between the language that a technical person uses and the one used by people in medicine, which needs common ground and will facilitate the process."

Dr. Sanhita Basu also mentioned this project's challenges as a small data set, differentiating between pneumonia and COVID pneumonia. 

The discussion also touched upon the roadblocks that such tremendously critical studies face when it comes to reaching the production cycle. On which Dr. Mitra said that the scenario is improving with various opportunities coming up. There are various start-ups that are taking an interest in such significant studies and taking them to the next level. "More collaborations from various research institutes, hospitals, and associations will bring these studies in action," mentioned Sushmita.

Dr. Saha concluded the discussion by saying, "for India we need to create a network with major hospitals and medical colleges being the nodes which can provide data for the research work."

The bright minds of the country have earned various accolades in the world, and hence with the right collaborations, interest from start-ups, and the right support from government bodies, the future of such research work is definitely bright.