What Are PIRIs — and Why Do They Matter?
In Nyemba health district in Tanganyika Province in the Democratic Republic of Congo, the local health facility runs four fixed sessions and four outreach sessions each month, reaching communities up to five kilometers away. But even with this effort, gaps remain. Children living farther out or those whose caregivers spend long hours farming or working away from home are often missed, leaving them vulnerable and unprotected.
Periodic Intensification of Routine Immunization (PIRI) helps close these gaps. These short-term, targeted efforts to boost routine immunization coverage give health workers the chance to catch up children who missed earlier doses and find zero-dose children — those who have never received any vaccine. By zeroing in on areas with higher risk or lower coverage, PIRIs strengthen the regular outreach system and ensure no child is left behind.
How PIRI Sites Are Selected
PIRI sessions are far from random. Health authorities, together with partners like VillageReach, carefully pinpoint areas where vaccination coverage is low, access is tough or the risk of outbreaks is high. In Nyemba district, health data revealed clusters of missed children, including infants whose families migrate seasonally to distant farming areas, making these sessions critical for closing the gap.
VillageReach supported the planning process – working with district teams to analyze the data, pinpoint zero-dose hotspots, rally community leaders and coordinate the logistics required to reach the right communities at the right time.
Preparing for the PIRI
Chief of the Tabacongo village. Photo Credit: Victor Useni
Once the location is selected, preparations begin weeks in advance. VillageReach works hand-in-hand with district health offices and community structures to review immunization and surveillance data, engage traditional leaders, provide supportive supervision and coordinate every detail – from vaccine transport to cold chain planning. This careful groundwork ensures that when PIRI day arrives, families are informed, vaccines arrive safely and sessions run smoothly.
Strong leadership and community involvement helped ensure high turnout for the PIRI session in Tabacongo village. Photo Credit: Patrick Kahondwa
CHWs: The Critical Link
Health workers reviewing registers and data tools to plan for the PIRI session — a key step in identifying zero-dose and under-immunized children. Photo Credit: Mariam Zameer
Community health workers are the heartbeat of successful PIRIs. They go door-to-door, finding unregistered or missed children, reminding mothers of the date and location and encouraging caregivers to attend. They also distribute the tokens that help track zero-dose and under-immunized children, ensuring an efficient flow of services on the day of the session.
Their connection to the community — and their knowledge of where children live — is essential. Without CHWs, many families simply would not know when or where to go, and many children would be left behind.
CHWs travel across villages and long footpaths to reach families and ensure every child is counted. Photo Credit: Victor Useni
Why Location Matters: The Case for Convenience
The PIRI held in the chief’s compound in Tabacongo proved a powerful lesson: bringing immunization closer to where life happens dramatically boosts participation. A familiar setting builds confidence and makes it easier for caregivers – saving time and reducing the effort required to attend.
Convenience is a cornerstone of immunization equity — and PIRIs make it possible for districts to bring services closer to the community, at the moments that matter most.
Beyond 5 km: The Importance of Mobile Sessions
Reaching children who live more than five kilometers from a health facility remains one of routine immunization’s toughest challenges. Under the Reaching Every District/Reaching Every Community (RED/REC) approach, these communities need “mobile” sessions — services that go beyond traditional outreach. Health workers often travel long distances, sometimes staying overnight to vaccinate children in remote villages.
In the past, VillageReach supported health facilities and district teams to implement these mobile strategies – providing transport, cold chain support and the logistical planning needed for health workers to stay overnight and deliver vaccines safely. These approaches brought immunization closer to families who might otherwise remain unreached and proved the power of meeting communities where they live.
Today’s PIRIs are able to reach children who may have been missed through intensified catch-up, but health systems work best when they meet people where they are — not the other way around.
VillageReach’s Role in Strengthening Routine Immunization
VillageReach is a key partner in helping governments plan, implement and evaluate PIRIs. The team provides real-time data support, strengthens microplanning, ensures cold chain functionality and works with district leaders to identify underreached communities. By combining data insights with local partnerships, VillageReach supports immunization systems that truly reflect the realities of families’ lives.
Strong partnerships between health workers, CHWs, leaders and VillageReach help ensure no child is left behind. Photo Credit: Mariam Zameer
A System Designed for the Community
In Nyemba district, PIRIs showed that small changes could spark big results. Choosing the right location, empowering CHWs and engaging leaders — unlocked major gains in coverage. Whether through PIRI, outreach or mobile sessions, the lesson is clear: health systems thrive when they are built around the rhythms and realities of the people they serve.