30 Apr Good immunization data is not just for experts and nerds, it is for us all
This blog was originally published on the International Vaccine Access Center (IVAC)‘s website and is cross posted here with permission. The blog is part of the #ProtectingKids story roundup. Read all the stories here.
There is a popular saying that you cannot manage what you cannot measure. This is so true for the global effort to close the immunization gap. We need to localize and measure the gap before we can close it. Having good immunization data to evaluate how well we are reaching all children is a critical ingredient for success.
I was poignantly reminded of this fact a few weeks ago when I visited Damangaza community, an urban slum in Nigeria’s Federal Capital Territory, where one of our Women Advocates for Vaccine Access (WAVA) member works. A temporary settlement, Damangaza is made of mud huts, open sewers, zero infrastructure, friendly adults and playful children. This generous community hosts more residents than it can comfortably accommodate, even welcoming internally displaced families fleeing from Boko Haram. A mere 20 minutes drive from the heart of Abuja, the contrast in wealth and access between the community and the nearby Abuja city center couldn’t be any starker.
When WAVA member, Vaccine Network, began working in Damangaza a few years ago, majority of the children had never been vaccinated. The year before, an outbreak of measles swept through the community killing many children in its wake. Although by no means hard to reach, a community like this is one of many settings where children easily fall through the cracks and are missed by immunization services.
Little wonder current data shows that one in five African children is under-vaccinated. If we are to reach that fifth child, we need accurate and timely data to tell us who that child is, where they live and why they are missed. This is a big challenge in Nigeria where the two main sources of immunization data (survey and administrative) do not speak to each other.
Survey data is obtained by interviewing a representative sample of households in the communities about their child’s immunization status. The main ones are the National Demographic Health Survey (NDHS) or the National Immunization Coverage Survey (NICS) conducted every 4 to 5 years. Survey data is richer in details and considered the gold standard. Administrative data on the other hand is based on clinic and health facility records of children who are vaccinated in fixed or outreach posts; it is collated monthly. It is therefore more available to support program management.
Unfortunately, there is usually wide disagreement between the administrative and survey coverage estimates, with the administrative always higher than the survey for comparable years. For example, national coverage with the third dose of the pentavalent vaccine in the 2013 NDHS survey was 38% but 58% by administrative data. Put another way, survey says we reached nearly 4 in 10 kids while administrative says we reached nearly 6 in 10 kids. Which data is accurate?
Diving deeper in the NDHS 2013 raises concerns about retention in care and equity of coverage. For example, while 51% of Nigerian children get their first dose of pentavalent, only 38% end up receiving all three recommended doses, reflecting an absolute drop out rate of 25%. Furthermore, only a quarter of one-year olds received all required vaccines, while as many as 1 in 5 received no vaccines at all.
Looking the beyond the national average reveals staggering disparities by geography, residence, mother’s education and wealth quintiles. According to the NDHS, a child in the north western state of Sokoto is 32 times less likely to be vaccinated than his peer in the south eastern state of Imo. A child living in a rural area is 2.5 times less likely to be vaccinated than her mate in the city. If a child is born of a mother with no education, that child is 7 times less likely to be vaccinated than another child whose mother has secondary school education or more. Children from the poorest fifth of the wealth ladder are 11 times less likely to be vaccinated than their peers from the richest fifth.
Sobering statistics indeed. As I cradled adorable twins Hassan and Husiana in my arms during my visit to Damangaza, I knew the odds were stacked against them in terms of access to vaccination. Their mother had no education, she was in the lowest rung of the wealth ladder and they live in an urban slum. But then again, it struck me that their disadvantage can be overcome if we are intentional about finding and vaccinating children like them wherever they may be. But we will need good and timely data to do that. If administrative data over estimates coverage, we will have a false sense of accomplishment and still miss many children. If survey data is accurate but comes only twice in a decade, it is too infrequent to help us manage the program. We must find an alternative.
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Dr. Chizoba Wonodi is the Nigeria Country Program Lead at IVAC. |
As the global community works on ways to improve immunization data, I see a third way. This is to empower communities to generate and use their own data to track births and children’s immunization status. Through IVAC’s work on accountability for routine immunization in Nigeria, I have seen that it is possible use community structures like religious and traditional leaders or Ward and Village Development Committees to count how many children are born in the community every month. If health workers have an accurate number of births in their catchment area, the true target population, it is easy for them to measure how well they are doing with vaccinating kids.
Community structures can also be used to track dropouts or left-outs, tracing them right down to the compound and household where the children live. Such real time information will not only help the health worker do their job better, it will also give community leaders a sense of ownership of the immunization program. I look forward to the day when a village chief can tell his community’s target population and vaccination coverage; that day will bring us many steps closer to bridging the immunization gap. Data is not just for experts and nerds; it is for all of us.
Dr. Chizoba Wonodi is the Nigeria Country Program Lead at IVAC.