Table 2 Three successful strategies to improve immunization for migrant population by Theory of Change

Stop charging immunization service fee or immunization insurance.

Immunizations for migrant population were responsible by the local living places, while they were not in their original Hukou places. After 2005, all the immunization funds were allocated directly to the local immunization clinics based on the total population in each area, and migrants were also included. Immunization clinics had financial incentives to provide immunization services to migrants.

In 2004, only 80% of migrant children in Baicheng City, Jilin Province had appropriate immunizations, and this rate increased to more than 95% in 2006 right after “Regulation about Vaccine and Immunization Management” was implemented in 2005 [24].

The revision of “People’s Republic of China’s Law about Preventing and Controlling Communicable Diseases” in 2004 specified that EPI immunizations should be free of charge.

In 2005, the State Council announced “Regulation about Vaccine and Immunization Management” and specified that five EPI immunizations should be provided to people free of charge without extra immunization service fees or immunization insurance.

Manage immunization certificates well.

Immunization certificates were checked when children received annual physical examinations and got into kindergartens and schools. Catch-up programs were provided to children without up-to-date immunization records in their immunization certificates or without immunization certificates.

In 2007, 95% of migrant children in Chengdu City, Sichuan Province had immunization certificates and their age-appropriate immunization rates were more than 90% [25]. In 2008, 95.8% of migrant children had immunization certificates in Yangzhou City, Jiangsu Province, and their 5 vaccine’ immunizations rates were 87.5% [26].

“Regulation about Vaccine and Immunization Management” in 2005 specified that the immunization certificate should be issued to newborn babies within one month after delivery by the local residential immunization stations.

Pay more attentions to special children for their immunization, including migrant children, children violating family planning policies, and children without ability to pay immunization service fees or insurance.

For children without ability to pay, immunization service fees or insurance were waivered. Local immunization staffs tried to search for special children without up-to-date immunizations, and provide appropriate immunization services to them. The local immunization staffs tried to collect information about newborn children by collaborating with other departments. It was allowable not to record their real names and/or addresses for children violating family planning policies, but the immunization certificates were still issued to them.

After the immunization policy for special population was implemented in Jiangle County, Fujian Province, 80% of migrant people received timely immunization information and 90% of parents with migrant children went to immunization clinics to receive EPI immunizations [32]. Catch-up immunizations were provided to children without up-to-date immunizations, and immunization insurance was also waived.

In 1998, the former Ministry of Health announced “Management Plan for Special Population’s Expanded Program for Immunization” and tried to improve immunization work for special children.