Introduction

The Delta variant is scientifically known as the B.1.617.2. variant, a Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mutation that first identified in India in December 2020. The Delta variant is a more transmissible form of the novel coronavirus that has spread to at least 77 countries and regions, becoming the most commonly spread variant. Currently, it is one of the dominant strains of the virus in both India and then Great Britain. Reports show that by the end of June, Delta had already made up more than 20% of cases in the U.S., according to the Centers for Disease Control and Prevention (CDC). The WHO also classified the Delta variant as the variant of concern (VOC).

Is the Delta variant more dangerous?

According to recent studies data, the Delta variant is 40 to 60 percent more transmissible than the Alpha variant which was discovered in the United Kingdom. Meanwhile, the Alpha variant was already 50 percent more transmissible than the original corona viral strain from Wuhan, China. The Delta has swiftly become the dominant strain worldwide, causing a new increase in infections despite the population’s high vaccination rate. Multiple scientists state that the Delta variant is by far the most infectious and hypertransmissible variant of the virus we’ve seen to date.

Furthermore, there is some evidence that the Delta variation grows more rapidly inside human’s respiratory tracts and may cause more severe illness. Research in Scotland discovered that patients with the Delta variant were 85 percent more likely to be hospitalised than those with the Alpha variant. However, due to the time lag between hospitalizations and deaths, there is insufficient data to say if Delta is more lethal than other variants.

Efficacy of vaccination against the Delta variant?

Fortunately, vaccination still appears to provide adequate immunization against the Delta variant. Reports from England and Scotland state that although the Delta vaccine is less effective than the Alpha vaccine after a single dose, the analysis continues to show that vaccine effectiveness against Delta is higher after two doses. However, the overall effectiveness of Delta compared to Alpha is still lower.

In a preliminary analysis, two doses of the Pfizer or Moderna vaccine appeared to be about 88% effective against the disease and 96% effective against hospitalization with the Delta variant, according to Public Health England. The AstraZeneca vaccine, however, which has not been authorized for use in the U.S. was about 60% effective against the disease and 93% effective against hospitalization with the Delta variant.

Meanwhile, according to preliminary data, 99.5 percent of COVID-19 deaths occurred among those who had not been vaccinated. Various vaccine makers and companies are providing their best in testing booster shots to find out if they can provide better protection against the Delta variant and other variants that emerge in coming months. Pfizer also announced that it will seek FDA authorization for a booster dose in August.

Conclusion

Even though the Delta variant of corona virus has caused outbreaks and is dominant in multiple countries, it showed to be more contagious after mutation, relatively less effective in Delta vaccine compared to other variants; the public compliance is a major factor as well. Following the rules and SOP, taking care of the personnel hygiene is the primary and essential step of preventing the infection of coronavirus no matter which variants it is. Fortunately, the scientific evidence has shown that our approved Covid-19 vaccine is still pretty effective in protecting us against severe disease, hospitalisation, and death caused by the Delta variant. As a responsible Malaysia citizen, receiving Covid-19 vaccine as per schedule is an act of assistance against the pandemic, so please do not hesitate for vaccination.