Dr Senjuti and her team of researchers completed the genome sequencing for Sars-Cov2 for the first time in Bangladesh. In an interview with Dhaka Tribune's Kohinur Khyum Tithila, she speaks of the importance of genome sequencing in tracking and controlling the spread of viruses or bacteria
Along with her father Dr Samir Kumar Saha, Dr Senjuti Saha led a team of researchers to successfully complete the genome sequencing for the novel coronavirus – Sars-Cov2 – for the first time in Bangladesh in May last year.
Dr Senjuti, a microbiologist working at the intersection of Clinical Microbiology and Global Health as a scientist at the Child Health Research Foundation (CHRF) in Bangladesh, recently published a paper titled, “Covid-19 rise in Bangladesh correlates with increasing detection of B.1.351 variant” with a team of researchers in BMJ Global Health journal.
Would you briefly explain the findings of the paper you authored?
We started SARS-CoV-2 genome surveillance in April last year but found no significant changes in the circulating viruses from between April and December 2020. Both the death rate and infection rate were declining till December.
We started seeing a change in January this year.
About 21% of the infections were by the UK variants. In February and March, the South African variant started dominating. The South African variant clearly correlated to the increasing infection rate. This paper presented this correlation scientifically.
Why should Bangladesh invest more in genome sequencing?
Genome sequencing is not really rocket science. I think any lab in Bangladesh conducting PCR tests can learn genome sequencing. However, researchers need to be consistent and patient, use their resources optimally and analyze the data intelligently.
We need more genomic surveillance of different kinds of viruses and bacteria. Genome sequencing is not just crucial to understand coronavirus mutation, it can also help us determine if a vaccine would work on the circulating variants or not.
Take the example of dengue fever. Too many people were infected two years back in Bangladesh. Did we pay as much attention to genome sequencing for this virus? Genome sequencing is crucial for tracking and controlling the spread of any virus or bacteria.
What can you find by genome sequencing a virus?
There are three major things which can be identified by sequencing the coronavirus – tracking and transmission, flagging important mutations, and determining the reproducing number of viruses. We can tell how rapidly the virus is spreading.
We can look at the sequencing data and tell where the virus comes from. We can find out the important and dangerous mutations and stay alert.
And finally, if we can determine the reproduction number, we will be able to tell how contagious a variant could be.
Some are showing reluctance to get vaccinated since they can still contract the virus. What is your take on it?
People can still contract some variants of the virus even after being vaccinated. Some vaccines do not really protect against infection, but these vaccines have the ability to reduce severity of the disease, that is reduce the need for hospitalization or the risk of death.
Any vaccines, take the example of the Oxford Astrazeneca vaccine, can reduce the number of hospitalization and ICU admission in vaccinated Covid-19 patients. At this moment, the most crucial thing is to not overwhelm the hospitals with Covid-19 patients.
What is the most contagious variant so far?
There is no published data on head-to-head comparisons of all variants. However, there are four variants that we are concerned about – B.1.1.7 (UK), P.1 (Brazil), B.1.617.2 (Indian) and B.1.351 (South Africa) – which appear to be more infectious than the original SARS-CoV-2 because of certain mutations.