Immunisation coverage of DTP vaccine takes a hit in GurugramUpdated: Sep 24, 2020, 23:52 IST
With schools having been shut since March 25, due to a nationwide lockdown to prevent the spread of Covid-19, the district’s immunisation coverage of the diphtheria-tetanus-pertussis (DTP) vaccine has taken a significant hit, revealed the data shared by the district health department.
Officials and experts fear this may lead to a spike in the cases of diphtheria among children over the next six to eight weeks. Gurugram and the neighbouring Nuh have already seen four suspected diphtheria deaths since July this year.
The health department runs 11 immunisation programmes, covering a range of vaccines for preventable diseases (VPDs), such as measles, diptheria, polio, mumps, rubella and others. This year, due to Covid-19, the coverage targets of all 11 campaigns have been reduced. Immunisation efforts in Gurugram are lagging behind even in these lowered targets with staff stretched to capacity on account of Covid-19 outbreak, officials revealed.
For example, a booster dose of the DTP vaccine, administered to children at age five, achieved 113% coverage last year (with 38,872 children inoculated as against a target of 34,375). This year, only 55% of the target has been met, with 7,408 children inoculated (out of 13,250 that were targeted for coverage till end August). Even sharper drops were seen in coverage of the tetanus-diptheria (TD) vaccine, which is administered to children at ages 10 and 16. Only 23% of the 10-year vaccine’s coverage target for August has been achieved (as opposed to 66% coverage last year). Similarly, the 16-year vaccine achieved only 11% coverage this year (as opposed to 51% last year).
“It is unlikely that we will be able to meet or exceed our targets this year, whether for diptheria-tetanus-pertussis or any of the other campaigns. We are aiming for at least 90% coverage of all 11 vaccine programs, which should provide adequate herd immunity among vulnerable communities,” said Dr Naresh Garg, district immunisation officer, Gurugram. While most vaccine campaigns are conducted door-to-door, booster doses of the DTP and TD vaccines, Garg explained, are administered in schools. “But schools have been shut since March, so naturally, these vaccines have achieved very low coverage this year. This would create ‘immunity gaps’ in the population, but we are going to set up weekend vaccine camps specifically for DTP and DT vaccines at all anganwadis in the district, every Saturday. Outreach programmes will also be done by ASHA workers to let people know,” Garg added.
However, the public health ramifications of reduced immunisation cover are already manifesting, according to experts. Dr Bindu Yadav, the World Health Organisation’s (WHO) surveillance medical officer in Gurugram, said, “Since July, Gurugram district has seen one confirmed case of diphtheria and seven suspected cases, whereas last year we saw only six cases. And the annual peak of the disease is still about eight weeks away. We are very likely to see a higher number of diptheria cases among children this year, which is indicative of low vaccine coverage during the lockdown.”
Suspected cases of diphtheria have already been reported in Nuh, in which four children between the ages of five and 15 have died since July this year. Twelve other children are suspected to have contracted the bacterial illness, according to data provided by Dr Vimlesh Tiwari, district epidemiologist, Nuh. “Our district has historically struggled with immunisation cover. Last year we had about 150 cases of diptheria. This year, we are on the alert for more. Diptheria cases typically peak around late October and early November,” Tiwari said.
Dr Sanjeev Tanwar, the WHO’s surveillance medical officer in Nuh, also added that suspected outbreaks of diptheria have been reported in districts of Alwar and Bharatpur in Rajasthan, which share their borders with Nuh. “I say suspected cases only because of technicality. Clinical symptoms of diphtheria are unique to the illness, so most cases are treated based on clinical discretion, and not necessarily based on lab confirmed results,” Tanwar explained.
Dr Rajib Dasgupta, chairperson, Centre of Social Medicine & Community Health at Jawaharlal Nehru University, Delhi pointed out that diphtheria cases and/or outbreaks in the under-15 years age group have recently been reported both from Indian states, as well as countries in the region.
“Take Bageshwar district in Uttarakhand, for example, or even parts of eastern Myanmar or central Vietnam. Like all routine health services, immunisation programmes have been affected to varied extents by the ongoing Covid-19 crisis. This may render pools of unimmunised children and adolescents susceptible to outbreaks of vaccine preventable diseases. All states are therefore making serious efforts towards catch-up immunisation,” said Dasgupta.