More than two months after Bangladesh completed a special measles-rubella (MR) vaccination campaign, measles infections and deaths have not declined as expected, raising questions from public health experts over the drive’s effective coverage despite official claims of 103 percent target achievement.
After measles infections emerged at the start of this year, the outbreak expanded significantly in March. The government began recording measles infections and deaths on 15 March.
According to the Health Services Division, the special vaccination campaign began on 5 April in 30 upazilas and municipalities across 18 high-risk districts. The campaign was later expanded to four city corporations on 8 April and then nationwide from 20 April. The target was to vaccinate 18,015,064 children aged between 6 months and 59 months. More than 18.48 million children were vaccinated, exceeding the target and representing 103 percent coverage, according to official figures.
An analysis of data from the Directorate General of Health Services shows that the chain of measles transmission was not fully broken even after the campaign ended. That means the virus has continued to circulate in the community two months later.
Scientists say protective antibodies generally develop within 14 to 28 days after an MR vaccine dose.
Professor Dr Benazir Ahmed, a former member of the government’s National Technical Advisory Group on Immunisation, told Ajker Patrika: “At least 95 percent effective vaccine coverage must be ensured to control measles transmission. There were shortcomings in publicity, preparation and target-setting. That is why infections are not falling as expected. The calculation behind the claim of 103 percent vaccine coverage is also not accurate.”
According to the latest update issued by the Directorate General of Health Services on Sunday, 938 people with measles symptoms and 113 confirmed measles patients were identified in the previous 24 hours. Four people died with measles symptoms.
Since 15 March, Bangladesh has recorded 117,648 patients with measles symptoms and 14,431 confirmed measles cases. Deaths stand at 693 among patients with measles symptoms and 95 from confirmed measles.
Claiming that infections are declining, Directorate General of Health Services Director General Professor Dr Prabhat Chandra Biswas told Ajker Patrika: “Previously, the number of patients with measles symptoms was more than 1,000 a day, but now it has come down to between 600 and 800. The vaccination campaign ended on 20 May. Those who received the vaccine on the last day need three to four weeks to develop immunity. Many infected children develop complications including pneumonia. Because of these complications, deaths may occur even several weeks later. It would not be correct to view all deaths as the immediate result of active measles infection.”
Based on Directorate General of Health Services data, analysis using 6-12 April as the first epidemiological week shows there were 7,119 symptomatic measles patients that week. The number rose to 8,422 in the third week. The outbreak reached its peak in the fifth week, from 4 to 10 May, when both symptomatic and confirmed measles cases nearly doubled.
During that fifth week, deaths from confirmed measles and deaths among patients with measles symptoms rose to more than two and a half times the previous week’s level.
In the eighth epidemiological week, from 25 to 31 May, there were 7,123 new symptomatic patients and 427 confirmed measles cases. Deaths during that period were 53 among symptomatic patients and four from confirmed measles.
In the 14th week, from 6 to 12 July, there were 5,862 symptomatic patients and 868 confirmed measles cases. Deaths during that period were 19 among symptomatic patients and one from confirmed measles.
In the 15th week, from 13 to 19 July, symptomatic cases rose again to 6,168 and confirmed measles cases to 931. During the same period, 29 more people died with measles symptoms and one person died from confirmed measles.
The figures indicate that infections and deaths continued nearly two months after the vaccination campaign ended.
Public health and epidemiology experts say that, despite the official claim of 103 percent coverage, a significant number of children remained outside the reach of vaccination. They say at least 95 percent effective immunity in the population is required to break measles transmission.
Experts said the situation resulted from gaps in intensive field-level searches, door-to-door identification of unvaccinated children and effective microplanning.
On evaluating vaccine effectiveness in children, Dr Kazi Ahmed Zaki, director of the Institute of Epidemiology, Disease Control and Research, told Ajker Patrika: “Research has begun to assess how much immunity developed in children after vaccination. Initially, samples were collected from children in the 30 most affected upazilas. More systematic sample collection is now under way.”
Dr. Mushtuq Husain, former principal scientific officer at the Institute of Epidemiology, Disease Control and Research, said: “Vaccination alone cannot control transmission. Infected children must be identified quickly, isolation must be ensured, contacts must be brought under management, and an integrated public health response must be made effective. In our case, there were shortcomings in these measures.”
Director General Prabhat Chandra Biswas said the vaccination campaign had been launched quickly in an emergency using data from the 2022 census. He added that, alongside routine immunisation, house-to-house searches are now under way.
Professor Dr. Mahmudur Rahman, chairperson of the National Verification Committee for Measles and Rubella Elimination and former director of the Institute of Epidemiology, Disease Control and Research, said: “Children under six months cannot be vaccinated, so they remain at risk of infection. There are also some children over five years old who did not receive routine vaccines in the past. On the other hand, a significant number of children remained outside the target group of the special vaccination campaign. Therefore, claiming 103 percent coverage does not reflect the real situation. To assess the situation, hospital admission data should be analysed alongside surveillance data. At the same time, it is necessary to scientifically investigate whether there are other reasons behind the prolonged transmission.”