The collection, processing, use and interpretation of immunisation data are fundamental to the work of the Vaccine Alliance.

Without detailed and accurate information on the numbers of children vaccinated, and vaccine stocks, it is extremely difficult to improve coverage levels, identify those still missing out on life-saving immunisations and evaluate the effectiveness of immunisation programmes.

This is why Gavi is supporting countries’ efforts to strengthen their acquisition of high quality immunisation data, and their capacity to use this data to improve immunisation coverage and equity.

As part of its current data strategy, in 2018 Gavi supported 625 data-related activities across 65 countries. Investments totalling US$ 56 million were used to upgrade data collection systems to ensure that timely data is available, fit-for-purpose and used for immunisation programme planning, monitoring and risk mitigation.


Data highlights the economic benefits of vaccination

Data highlights the economic benefits of vaccination

In 2018, Nepal’s Ministry of Health worked with researchers and health professionals from the Nepal Paediatric Society, the University of Oxford (UK), Johns Hopkins University (Maryland, USA) and the University of Otago (New Zealand) on a Gavi-funded project to assess the economic impact of the recent roll-out of pneumococcal conjugate vaccine (PCV) in Nepal.

Based at Patan Hospital, Lagankhel, and drawing on data gathered from the local population, the researchers demonstrated that the roll-out of PCV coincided with a sharp fall in the prevalence of Streptococcus pneumoniae, the bacterium responsible for most cases of pneumonia among people living in urban Nepal.

Data from the project was also used to estimate the economic costs associated with the disease, an episode of which can place a significant financial burden on families. In 40% of recorded cases, the average costs associated with the hospitalisation of a child for pneumococcal disease (US$ 122) exceeded parental monthly income by a factor of 1.5; productivity loss from missed work was estimated to add a further US$ 66 to the cost burden.

While the project clearly revealed the potential of PCV to limit the impact of pneumococcal disease, it also demonstrated the benefits of data gathering. Insights gained from this local-scale project will inform policy decisions about the use of PCV across Nepal – and beyond its borders.

Nepal was also selected as the host country for the first large-scale, randomised controlled trial of a new typhoid conjugate vaccine, Typbar, prequalified by the WHO early in 2018. According to the WHO, between 11 and 21 million cases of typhoid occur worldwide each year, leading to 128,000–161,000 deaths annually, many in young children.a Typhoid represents a growing public health concern in Nepal where the disease is endemic, and the burden is likely to increase due to the causative agent, Salmonella typhi, becoming resistant to antibiotics.  

During late 2017 and 2018, more than 20,000 children from the Lalitpur District of Kathmandu were enrolled in the TyVAC trial, which was designed to test the new vaccine’s efficacy in an endemic setting. The trial was coordinated by researchers from the University of Maryland, USA, and funded by the Bill & Melinda Gates Foundation with support from Gavi and the Typhoid Vaccine Acceleration Consortium (TyVAC).

Data accumulated as part of the trial, which included information on local and systemic adverse reactions to the vaccine, was reviewed by the International Data and Safety Monitoring Board (DSMB) who concluded that it had no concerns about the safety of Typbar.

a - WHO website. Typhoid. 


Making data experts of us all

Making data experts of us all

Good data does not collect itself: acquiring good data requires expertise.

To improve the acquisition and quality of Expanded Programme on Immunization (EPI) and vaccine-preventable disease data across the lower levels of its health system, Kenya launched a pilot programme in 2018 to help individual health workers increase their data skills and expertise.

The STOP Immunisation and Surveillance Data Specialist (ISDS) pilot programme employed five ISDS consultants, who worked across 94 local health facilities in five counties (Busia, Kitui, Marsabit, Nairobi and Tana River).

The strength of the programme lay in its focus on improving skills, achieved in part by capitalising on existing in-country disease surveillance expertise developed by the Global Polio Eradication Initiative.

As a result of the pilot, funded by Gavi and managed by the US Centers for Disease Control and Prevention (CDC), the use and analysis of EPI data in all five counties improved.

“There was a notable improvement in data agreement between different immunisation recording and reporting tools,” reports Health Scientist Alyssa Wong, a member of the CDC team responsible for implementing the STOP-ISDS strategy. “By the end of the pilot in June 2018,” she adds, “nearly all ISDS priority health facilities had updated monitoring charts, correctly calculated drop-out rates and adequately archived data. Health workers became significantly more knowledgeable about how to calculate basic surveillance and EPI indicators.”

While data use remains a challenge, and there is scope for further improvement, significant progress has been made in reducing the tendency to overreport vaccine coverage rates in Kenya. Based on the success of this pilot, similar initiatives have since been launched in the Lao People’s Democratic Republic and Madagascar.


The impact of data mentors

The impact of data mentors

Many districts in Uganda experience electricity and Internet outages, compromising efforts to use digital health records.

Data collection tools and data archiving practices aren’t always harmonised between health facilities, and immunisation data is underused. However, following the recent introduction of a mentorship scheme, significant improvements in data capture have been made.

Since the start of 2018, 89% of Uganda’s health facilities have participated in the Data Improvement Team Strategy. In total, members of 438 health teams received training in how to better capture and use immunisation-related data.

As the results of a recent evaluation have demonstrated, the Strategy has yielded significant benefits. For example, the proportion of health facilities that could correctly identify their target population (children under the age of one year) increased from 45% to 75%, and the use of vaccine control books increased from 58% to 78%.

There was also a modest improvement in the use of health centre registers that document children’s health and immunisation records . However, the evaluation revealed that concordance between these registers and the electronic District Health Information System (DHIS2) increased only slightly, from 32% to 37%. That suggests further work needs to be done to better utilise child registries for tracking children and their health needs.

United Republic of Tanzania

A fully digitised vaccine supply chain

A fully digitised vaccine supply chain

Of the examples featured here, the improvements that have been achieved in the United Republic of Tanzania stand out as being the most innovative in terms of their scope. In 2018, systems were interlinked to create a truly digitised immunisation supply chain information system that allows healthcare workers to match vaccine doses to children, thereby increasing efficiencies and reducing wastage.

In 2018, local medical officers began using wireless digital tablets to track which children received which immunisations in a pilot scheme covering more than 1,300 health facilities across four regions. The benefits of using electronic methods of record-keeping quickly became apparent, especially in the most remote places, for example, within the harsh, dry highland plains of the Ngorongoro region that is home to the Maasai tribespeople.

Because many Maasai children are nomadic, they do not always attend the same clinics. This makes it particularly difficult to ensure these children receive all their vaccinations at the appropriate time. Before this “digital revolution”, the success of immunisation programmes among the Maasai depended on hope – hope that children would attend and hope that their families would bring the correct paper records of their vaccination history.

Now, a swipe of a finger instantly brings up the medical records of mothers and infants, and the vaccinations their children need. The tablet-based system is a vital component of the country’s new EIR system, which enables health workers to seek out children who are missing out or defaulting on their routine immunisations. In a country where barely one in two children have their births registered this represents a crucial step forwards and is contributing to improvements in immunisation coverage among a previously underimmunised population subgroup.

Created as part of the United Republic of Tanzania’s Better Immunisation Data (BID) initiative, the new Electronic Immunisation Register (EIR) is largely a country-driven project, produced by PATH with support from the Bill & Melinda Gates Foundation.

EPI Manager Dr Dafrossa Lyimo played a central role in its design, ensuring the EIR was also integrated with the country’s Vaccine Information Management System (VIMS), another paperless system that now monitors and facilitates vaccine supply levels, and the equipment used to store vaccines at cool temperatures, across the country.

Access to this information means that health workers preparing for vaccination sessions in their clinic or community can quickly see how many vaccines are in stock and order new supplies as necessary. This helps with forward planning and ensures that health workers have enough vaccine doses to immunise all children who attend. By anticipating demand, this technology is also helping Dr Dafrossa’s team better manage national vaccine stock levels, thus reducing stock-outs and wastage.

Such advances in data management are not only welcome, they are fundamentally necessary if we are to achieve our goal of reaching every single child with live-saving immunisation by 2030. That requires the global health community to continue to invest in innovative ways to acquire and analyse robust data. Ultimately, it will be the data that tells us if we have succeeded.

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