At the end of last year, many were beginning to see the light at the end of the long, drawn-out tunnel that the pandemic was.
The Pfizer-BioNTech, Moderna, and Oxford-AstraZeneca vaccines were approved by governments in quick successions, and for the first time, we had taken the fight to the virus itself. Then came the variants.
Dr Senjuti Saha, the microbiologist who completed the first genome sequencing of the novel coronavirus in Bangladesh, expected it to mutate.
But according to her, the variance seen in the SARS-CoV-2 virus was something many in the scientific community did not expect.
Variance in viruses occurs through mistakes made in the codification of its own genome.
Every time a virus infects a cell, it replicates itself into copies. When those copies are made, occasionally a mistake is made in the RNA of the virus, which are the mutations.
When mutations in a virus stabilise and spread, they form a variant.
Most of the time, the mutations are harmless, or even beneficial, but as in the case of the Alpha (UK), Beta (South Africa), Gamma (Brazil), and now Delta (India) variants, they can sometimes cause the virus to become more aggressive in its transmission or symptoms.
Dr Senjuti Saha said, "There were some discussions going on that this virus might mutate and become either more transmissible or more dangerous, but we did not really know what exactly it would become."
"And then once they started spreading, the first variant we were really concerned about was the Alpha variant in the UK, which we very quickly realised was spreading faster than the original one."
Variants are more likely to occur in regions where transmission is very high, as there are more cells replicating within more humans.
The Alpha variant first appeared in Kent, in the UK as infection rates were rising after a summer of low transmission across the British Isles.
"We are very scared now and we cannot exactly say what variant is coming next or how much worse it will be. But we just know that if we do not control infections, we are not going to be able to control [potential new variants]," said Dr Saha.
The Delta variant has wreaked havoc across the world, and Bangladesh is currently facing its full might.
The positivity rate in Bangladesh has reached 33%, and Dr Saha could not find an answer to whether this would get any worse.
"One in three people getting tested turn out to be positive. So we are already massively underestimating the number of cases for every positive case. I do not know how much more it can be when we are testing on this scale in Bangladesh, because our positivity at some level always saturates."
According to Dr Saha, as a consequence of limited data and testing, the numbers we see do not truly reflect the state of the pandemic in Bangladesh, and it could potentially be a lot worse than what is seen now.
Low rates of vaccinations in lower and middle-income countries are a further concern.
It is expected by many that from now on, most variants will arise from under-inoculated regions, just as the Delta variant did.
"My worry is that it is not a very good situation to be in when infection rates are this high, and you are not being able to rapidly vaccinate as many people as possible," said Dr Saha.
The government of Bangladesh has set a target to inoculate approximately up to 30% of the population by the end of this year, but Dr Saha believes that this is not high enough to curb the spread of new variants.
"Even if we reach 20% to 30% by the end of the year, it is just not enough, because we are a small country with a huge population. Diseases are transmitted very, very quickly, as people travel a lot within this densely populated country. I am very worried and I think we will have more waves unless something magical happens," she said.
The government has also been set back by many factors during its acquisition of vaccines, the most significant being India's decision to ban the export of vaccines.
On one hand, it had already paid for 30 million doses to the Serum Institute of India for its version of the Oxford-AstraZeneca vaccine and had only received seven million.
On the other hand, some developed nations such as the US are letting vaccines expire.
While vaccine equity schemes such as Covax are attempting to distribute much needed vaccines to less developed nations, it is only making a small brushmark on the larger picture.
Variance in the virus is still the biggest concern for Dr Saha. Currently, every distributed vaccine is extremely effective at preventing severe illness and hospitalisation, but with each new variant, a dangerous trend occurs.
The vaccines are not able to protect from infection from variants as well as it did with the original virus.
A recent study conducted by the Israeli Ministry of Health suggested that the Pfizer vaccine is only 41% effective at preventing symptomatic illness against the Delta variant.
"If I needed hospitalisation [without being vaccinated], chances are I would not need it if I am vaccinated. If I needed ICU support without vaccinations, chances are I would not need ICU support if I am fully vaccinated. But at some point, this advantage is not going to be there," Dr Saha informed us.
"At some point, if we let infections rise, if we keep on making space for the virus to transmit and replicate, it is going to figure out a way to completely evade vaccines," she added.