New Delhi: As India remains occupied with tackling the Covid-19 pandemic, the elimination targets for black fever or kala-azar could be missed for the fourth time in the last ten years.
Kala-azar, also known as visceral leishmaniasis, is a disease caused by protozoan parasites that infects organs such as liver and spleen, and is spread through sand flies — flies with hairy, brownish-gray wings. The use of Indoor Residual Spraying (IRS) of insecticides is the only way to prevent the build-up of these flies.
This year, the spraying of crucial insecticides has been delayed by almost two months in the four states where the disease is endemic due to the nationwide lockdown to curb the spread of Covid-19.
“The whole machinery is geared up to fight that (Covid-19). So, there is a limitation of human resources for other programmes,” said a Ministry of Health and Family Welfare official, who didn’t wish to be named.
Of the four states, Bihar restarted the programme only by the end of April while Jharkhand did it last week after dropping it when the lockdown was imposed on 25 March. West Bengal still hasn’t started the programme. Uttar Pradesh is planning to start it this week.
How kala-azar spreads
Kala-azar in India has a ‘unique’ epidemiological feature of being anthroponotic, which means “human beings are the only known reservoirs of infection”, the WHO says.
The female sandflies pick up the amastigote stage of the parasite while feeding on an infected human host. “The parasites undergo development and multiplication in the gut of sand flies which migrate to their mouthparts. The cycle in the sand flies is completed in about 8 days. Infection is transmitted to healthy human beings when such infective sand flies bite them.”
Under the IRS drive, the insecticide is applied to the indoor surfaces of houses and animal shelters. The insecticide being used currently is known as synthetic pyrethroid.
The spraying is done twice a year — March to April and October to November.
Under the National Health Mission (NHM), National Vector Borne Disease Control Programme is the agency responsible for the IRS drive, which is used in areas where the disease is prevalent. It coordinates the kala-azar elimination programme in India.
India has already missed the kala-azar elimination target thrice in the last decade. The initial deadline set by the National Health Programme (now NHM) was 2010, which was pushed to 2015 in the 12th Financial Plan Document. This deadline was later extended twice — to 2017, and then to 2020.
The target is to reduce the incidence of the disease to less than one case per 10,000 population at the sub-district level.
ThePrint reached out to Vandana Gurnani, Additional Secretary and Mission Director, NHM, and Manohar Agnani, Joint Secretary, Health and Family Welfare, for a comment via text messages and calls but did not receive a response.
Mapping the delay
Kala-azar is endemic to 54 districts across Bihar (33 districts), West Bengal (11 districts), Uttar Pradesh (six districts) and Jharkhand (four districts). These districts together account for nearly 130 million people, shows government data.
In 2019, Bihar reported 2,416 cases followed by 539 cases in Jharkhand, 86 in Uttar Pradesh and 87 in West Bengal.
This year, a total of 578 cases were reported in all four states until March — 430 cases in Bihar, 130 in Jharkhand, 14 in Uttar Pradesh and 4 in West Bengal.
Of the four states, the IRS programme, which typically begins in late March, was restarted in Bihar and Jharkhand.
“It was restarted in Bihar at the end of April. In Jharkhand, the IRS started on 20 March. However, the activity was stopped on March 24 due to Covid-19 outbreak. Now, the teams have been redeployed from 14 May,” said the official quoted above, who works closely on the elimination programme.
A health official in Uttar Pradesh said no harm has been done until now. “In UP, the incidence of disease is very low now, and in the last three years the targets for the elimination has been achieved.”
Atin Ghosh, Deputy Mayor of Kolkata who looks after the city’s health, vector control, disinfectant scheme, said, “Right now nothing is happening because of the Covid-19 situation.”
West Bengal is the oldest known kala-azar endemic area in the world.
Drive was to begin after 14 April
In a letter to principal secretaries and chief secretaries on 4 April, Union Health Secretary Preeti Sudan had ordered states and union territories to resume essential services including IRS after 14 April, when the first phase of the nationwide lockdown was initially slated to be lifted.
“Activities such as distribution of Insecticide Treated Nets (ITN) and indoor residual spraying (IRS) in targeted areas should be resumed after the lockdown,” the letter said. ThePrint has seen a copy of it.
This was to be implemented after 14 April as the restrictions were eased over the next phases of the lockdown, said sources.
The list of services in the letter on “maintenance of non-Covid essential services” included maternal, newborn and child health, prevention and management of communicable diseases, and treatment for chronic disease and emergencies. It also stressed that IRS teams should be provided personal protective equipment sanitizers, soaps and water.
‘Delay won’t harm’
In India, the government starts the process early so as to complete it before the start of the monsoon season, which begins in June, said a second health ministry official, who didn’t wish to be named.
“We start in March because we don’t want to get it delayed as it can’t be done in the monsoon season. Now, we will start in May and we will complete in one or two months. This won’t harm anything,” said the official.
According to the World Health Organization (WHO), the prevalence of vectors is dependent upon environmental factors including humidity, temperature and rainfall. The ecological factors like alluvial soil, kuccha mud-houses and large scale vegetation also influence build up of vector density, the agency says.
“Because of Covid preparation, there was a little delay but we will ensure that it finishes before the monsoon,” said the UP health official quoted above.