Cases of measles have been on the rise in India since the beginning of the year, but outbreaks in multiple states, lead by Maharashtra, has prompted the Union Health Ministry to now identify 85 districts across 16 states for an urgent measles outbreak response immunization (ORI) drive.
According to the World Health Organization, India has the highest caseload of measles with at least 9489 cases reported so far in the country this year.
Can measles swell into the next public health emergency in India?
In such a situation, what should the next public health move be? To find out, FIT speaks to experts.
Another Health Emergency?
"The outbreaks are occurring due to accumulation of susceptible children for more than two years," says Dr Giridhar Babu, Epidemiologist at Public Health Foundation of India, who has worked in the National Measles programme in the past.
There was also a massive drop in routine childhood vaccination during the COVID pandemic, which experts had forewarned could lead to a resurgence of vaccine-preventable diseases.
"This means that we have created new weaknesses because of India’s COVID response," says Dr Harikeerthan Raghuram, a public health researcher working on vaccine equity in Bhopal.
Containing measles once it starts spreading is hard because:
Measles is a highly infectious disease
"Up to 9 out of 10 susceptible persons with close contact to a measles patient will develop measles," explains Dr Giridhar Babu.
It mostly affects young children
"It can spread starting four days before the rash appears, and ending when the rash has been present for four day. Ideally isolation of 7 to 21 days prior to rash onset decreases mortality and morbidity. Unless other children have rash, it is difficult to isolate ahead of prodromal phase."Dr Giridhar Babu
However, the experts think it's unlikely that the current outbreak will spiral into a catastrophic situation like with COVID-19.
"Proactive surveillance, and supplementary immunization activities (mop-up’s) can aid in breaking the chain," says Dr Babu.
"We knew nothing about COVID, but we know about measles. We have a vaccine that is very effective in preventing infection, not just severe illness," adds Dr Dutta.
To break it down further, unless the virus mutates in a way that it would evade vaccine protection, we are good.
The Only Way to Prevent Measles
Vaccination is key, because "there's little you can do once you get it," adds Dr Dutta.
We have seen spikes in measles cases in the past, too.
The measles vaccine was invented in 1963, but the US saw another measles epidemic between 1989 and 1990.
The cause for this was traced to low vaccination rates among pre-schoolers, and a change in epidemiology of the virus that was now affecting younger kids.
Immunisation efforts were ramped up, and the US declared measles 'eliminated' in 2000.
However, due to a combination of reasons including but not restricted to misinformation, and vaccine hesitancy, the country saw another outbreak in 2019.
"Even if 80 of 100 children are vaccinated, only 68 children are immunized (85% seroconversion), leaving out 22 of 100 children susceptible to infection. If this continues for two years, the susceptible pool expands. Hence, it is very important to sustain a high level of coverage through a universal immunisation program and follow up with supplementary immunisation activities to prevent outbreaks."Dr Giridhar Babu
The bottom line is that historically, measles has been successfully restricted when robust vaccination drives were ensured. When vaccination laxed, the disease is known to make a comeback.
'Need More Disaster-Resilient Programmes'
One of the many lessons to take away from the COVID pandemic is that "if we face such disasters in the future, we should make sure that routine immunisations, and our other essential health services like TB and malaria programs don't suffer," says Dr Dutta.
"These programmes need to be made disaster resilient."Dr Ambrish Dutta, Epidemiologist, Public Health Foundation of India
"We need to understand that the health system does not work in a silo. There are determinants of health that are outside the typical purview of what is a health system," says Dr Harikeerthan Raghuram.
"Access barriers, and misinformation are huge causes of under vaccination both among children and adults."Dr Harikeerthan Raghuram
"We also need better public health surveillance. For example, we need to know who are the children who have been under-vaccinated," he says.
"Mop-up’s are necessary once in few years to cover children who are not seroconverted and at-risk newer members in cohort," adds Dr Giridhar Babu.
Strengthening surveillance and sustained high immunisation coverage are both vital measures that need to be undertaken before a public health emergency of any kind strikes.