How Kolkata has succeeded in controlling dengue

Dhaka and Kolkata – the distance between the two cities by road is approximately 325 km. Population density, urbanization, geographical features—both cities are almost identical. The two cities also have a close history of dengue outbreaks. Dengue appeared in the form of an epidemic in Calcutta in 1963. At that time, about 200 people lost their lives in dengue. And the outbreak in Dhaka in 1965. At that time dengue fever was called ‘Dhaka Fever’ in Dhaka.Since 2010, the Kolkata Municipal Corporation has cordoned off the Atghat to kill and prevent the spread of Aedish mosquitoes. They put more emphasis on killing mosquitoes at source. Ward-to-ward mosquito control committee by involving people.
Poet Ishwar Chandra Gupta, known for his sarcasm, has a rhyme, ‘Mosquitoes by night, flies by day, I am in Calcutta with this.’ Ishwarchandra was a nineteenth century poet. But that mosquito is now a big fear not only in Kolkata, but in big cities all over the world. The cause of this scare is the Aedes mosquito-borne dengue (RNA) virus. The history of dengue in Kolkata is about seven decades old. But Kolkata has now overcome this fear. How they controlled dengue is now a matter of public health interest.
Bangladesh Institute of Epidemiology, Disease Control and Research (IEDCR) advisor Mushtaq Hossain said, ‘Kolkata has succeeded in preventing the spread of Aedes mosquitoes and controlling dengue. The way they involved people in this work is instructive for everyone. We can use this experience.’
Like Kolkata, dengue started increasing in Dhaka in the late nineties of the last century. In the first six months of this year, the number of dengue patients hospitalized or died in Dhaka and other parts of the country is the highest in the history of the country. As of last Thursday, 27,547 people have been admitted to hospital due to dengue. A total of 146 people died. Public health experts fear that the dengue situation may be worse this year.
If you repel mosquitoes with a fogger, mosquitoes from one neighborhood go to another neighborhood. Nothing works. We therefore aim to eradicate mosquitoes at source. In the case of dengue, there is no other way.
Atin Ghosh, Deputy Mayor, Kolkata Municipal Corporation
On the other hand, 260 people have been infected with dengue in Kolkata this year, 1 person has died. Prothom Alo spoke to Calcutta Municipal Corporation Deputy Mayor Atin Ghosh and Chief Vector Control Officer Debashish Biswas about the reasons behind Kolkata’s success in dengue control and what measures West Bengal state and local institutions have taken. When it comes to dengue control in Kolkata, the names of these two come first.
What Kolkata did to control dengue
Kolkata has been moving forward with this goal from the very beginning to prevent mosquitoes from spreading and destroying them at the source rather than driving them away with fogger machines. Deputy Mayor Atin Ghosh has been a ward councilor of the Municipal Corporation since 1985. He was saying, ‘If you repel mosquitoes with a fogger, mosquitoes from one neighborhood go to another neighborhood. Nothing works. We therefore aim to eradicate mosquitoes at source. In the case of dengue, there is no other way.’
A three-tier infrastructure has been developed to control dengue in Kolkata. These works started around 2010. Apart from this, dengue control laboratories were established. It was led by Debashish Biswas.
Debashish was saying, ‘I propose a laboratory to control dengue. Unless the character of dengue is understood, it cannot be eradicated. The laboratory was built in 2011 with only four lakh taka. We didn’t need to do much. In the laboratory, it was only observed how mosquitoes grow from larvae. It was also shown to the mask workers. Three thousand field workers were trained. They were shown the character of mosquitoes in front of their eyes.
Three level committee
Kolkata Municipal Corporation has a total of 16 boroughs (administrative areas) and 144 wards. Each borough has 7 to 12 wards. Each ward has a mosquito control committee. It consists of ward councillors, doctors and local people. There are 6 to 15 workers. All staff have mosquito control training. These ward committees have a list of possible sources of dengue in the area. Kolkata has 100 days program every year. People involved in these programs work as ward level workers. During these six months, from January to June, they keep constant vigil. Surveillance is intensified during the mosquito outbreak season in July.
Bangladesh has a history of success in malaria control, spread of ursine, vaccination. Dengue control will also be successful if the people are involved.
Director of the disease control branch of the Department of Health. Nazmul Islam told Prothom Alo , ‘It is seen that Kolkata has been able to catch and monitor patients. Whenever a patient is found, his residence and nearby areas are disinfected. We didn’t have it that way here. They did not solve this problem in one day. It was a long effort.’
Political decision is the real thing
Chief Vector Control Officer Debashish Biswas wants to give the bulk of the success in controlling dengue in Kolkata to the political leadership. This entomologist said that the political leadership understood the need to involve people along with science to control this terrible problem. They let the experts do what they wanted to do. Gave full cooperation. Mosquito control is actually a matter of political decision.
Debashish Biswas feels that the name of Deputy Mayor Atin Ghosh comes first in Kolkata’s dengue control. He said that he has written a book titled The Public Figure Behind Public Health about Atin Ghosh’s role in dengue control . The book was published in 2015 by the German publishing house Lap Labert Academic Publishing.
The foreword of the book states, ‘An experienced, hard-working political leader who has brought unprecedented change in improving the public health situation. He has a strong desire to serve society. Atin Ghosh, Mayor-in-Council (Health) of the Municipal Corporation of Kolkata, West Bengal, India, has set a precedent for his work.’
Debashish Biswas has highlighted the remarkable work and achievements of Atin Ghosh in his book The Public Figure Behind Public Health . Wrote, ‘He revolutionized the prevention and control of malaria and dengue through mosquito control in Calcutta city. Political leaders from different parts of the world who are indifferent to public health work, they have a lot to learn from this leader of Kolkata.
Why is this situation in Dhaka?
This year, all previous records of dengue cases and deaths in Bangladesh are breaking. In the first six months of this year, the number of dengue cases and deaths has never happened in the first six months of the past. On July 19, the maximum 19 people died in a single day due to dengue. The Department of Health said that there have never been so many deaths due to dengue in one day. According to the notification of the department, the death rate of dengue till mid-July this year is 0.55. Last year (2022) dengue death rate was highest in the country. Then the death rate was 0.45.
The dengue situation in other parts of the country, including Dhaka, is critical, several government officials have said. Dhaka politicians are also aware of Kolkata’s success in controlling dengue. Dhaka North City Mayor Atiqul Islam told Prothom Alo , ‘We have learned about dengue control in Kolkata. We learned several things from there.’
However, public health experts feel that the way Kolkata has worked for a long time to control dengue, Bangladesh has not done so. It could have been done that way here.
The former director of the disease control branch of the health department, Bay-Nazir Ahmed told Prothom Alo last Tuesday , “Kolkata has developed a system to control dengue. We have had this problem for a long time but have not made any management. Lack of political will and short-sightedness are responsible for this. When problems arise, quick solutions are attempted. But it is a chronic problem. A permanent solution was not found based on the plan. Now the situation is very much out of control.’
A type of bacteria called Bacillus thuringiensis israelensis (BTI) has proven to be very effective in killing mosquito larvae. Debashish Biswas said BTI has been used since 1996 to prevent the spread of AIDS in Kolkata.
Mayor Atiqul Islam said that Dhaka North City Corporation is importing BTI. However, apart from these initiatives, public health expert Dr. Mushtaq Hossain. He said that Bangladesh has a history of success in malaria control, spread of measles, vaccination. Dengue control will also be successful if the people are involved.