Younten Tshedup  

Despite growing apprehensions, Bhutanese and foreigners living in the country gathered at vaccination stations last weekend, with prayers and hope, as Bhutan began its ambitious nationwide vaccination against Covid-19.

As of last night, 459,858 people were vaccinated in the country. However, to provide vaccination to those who could not avail the services due to other engagements, the health ministry had extended the campaign period by two more days over the weekend.

The campaign began on a high note with Prime Minister Dr Lotay Tshering and other cabinet ministers receiving the jab on the first day. The numbers nearly touched 100,000 on the second and third day.

Turnout at the vaccination stations started dropping since the fourth day. Only 23,811 people were vaccinated as of 8pm yesterday. Many attributed the drop to people reporting adverse events following immunisation (AEFI).

Experts with the national immunisation technical advisory group (NI-TAG) said that the drop in turnout might not be because of the AEFI. Dr Sonam Wangchuk said that the last few days of any such campaign saw low turnout as most of the general public would have been already vaccinated.

Considering the target population, he said that the country had covered more than 430,000 as of the sixth day of the weeklong campaign. He said that the remaining people would be the health and other active frontline workers who were engaged during the campaign and asked to take the jab after the campaign. “It also includes people who could not physically come to the vaccine centres due to their health conditions.”

There are more than 20,000 desuups of which majority are actively engaged in the vaccination campaign. And then there are the active health workers spread across 1,200 vaccination centres across the country. 

Dr GP Dhakal said that the health ministry would have been worried if the difference between the vaccinated and targeted population was huge and the turnout started dropping. “We have almost covered all the targeted population by the fifth day and perhaps that is why the number (turnout) has started to plateau.”

Herd immunity 

The reason why Bhutan opted for a time-based nationwide vaccination campaign was to achieve herd immunity in the community.

When enough people in a population become immune to a disease (in this case, Covid-19), the active chain of transmission is broken. As more people become immune either through the natural course of infection or with vaccination, those infected are less able to pass on the disease, and the spread of the disease slows down. This is when a community, country, or population achieves herd immunity.

Although Bhutan has covered almost 90 percent of its eligible population in the last seven days, until the second dose of the vaccine is administered, technically, the country is yet to achieve herd immunity.

Dr Sonam Wangchuk said that for the country to achieve herd immunity at least 75 percent of the entire population had to be vaccinated.

According to the 2017 Population and Housing Census, Bhutan’s total population at that time was 735,553. This means that to achieve herd immunity, around 551,665 had to be vaccinated (both the doses).

However, Dr Sonam Wangchuk said that the 75 percent coverage was considering the reproductive rate of the SARS-CoV-2 virus as four. “But we know that the average reproductive rate of SARS-CoV-2 virus is about 2 to 2.5,” he said. “That is why anything above 65 percent should be good enough for us because it would have a significant impact.”

He said that the efficacy of the vaccine was also critical in determining the coverage and herd immunity. “Initially, AstraZeneca or Covishield vaccine had an efficacy rate of 63 percent but now it has increased to 81 percent. Therefore, we are confident we would achieve the herd immunity.”

He added that despite fears and anxieties many turned up for the vaccination this time. “We would like to see the same response from public during the second dose. For those who are worried about getting sick, researches have shown that you will experience lesser AEFI during the second.”

He said, “We would also like to assure people that with the surveillance system in place, there is very little to worry about. Have confidence in us and get the second dose for the benefit of all.”