Immunization, urbanization and slums – a systematic review of factors and interventions

Abstract

BackgroundIn 2014, over half (54%) of the world’s population lived in urban areas and this proportion will increase to 66% by 2050. This urbanizing trend has been accompanied by an increasing number of people living in urban poor communities and slums. Lower immunization coverage is found in poorer urban dwellers in many contexts. This study aims to identify factors associated with immunization coverage in poor urban areas and slums, and to identify interventions to improve coverage.MethodsWe conducted a systematic review, searching Medline, Embase, Global Health, CINAHL, Web of Science and The Cochrane Database with broad search terms for studies published between 2000 and 2016.ResultsOf 4872 unique articles, 327 abstracts were screened, leading to 63 included studies: 44 considering factors and 20 evaluating interventions (one in both categories) in 16 low or middle-income countries. A wide range of socio-economic characteristics were associated with coverage in different contexts. Recent rural-urban migration had a universally negative effect. Parents commonly reported lack of awareness of immunization importance and difficulty accessing services as reasons for under-immunization of their children. Physical distance to clinics and aspects of service quality also impacted uptake. We found evidence of effectiveness for interventions involving multiple components, especially if they have been designed with community involvement. Outreach programmes were effective where physical distance was identified as a barrier. Some evidence was found for the effective use of SMS (text) messaging services, community-based education programmes and financial incentives, which warrant further evaluation. No interventions were identified that provided services to migrants from rural areas.ConclusionDifferent factors affect immunization coverage in different urban poor and slum contexts. Immunization services should be designed in collaboration with slum-dwelling communities, considering the local context. Interventions should be designed and tested to increase immunization in migrants from rural areas.Electronic supplementary materialThe online version of this article (doi:10.1186/s12889-017-4473-7) contains supplementary material, which is available to authorized users.

Reducing burden from respiratory infections in refugees and immigrants: a systematic review of interventions in OECD, EU, EEA and EU-applicant countries

“…This evidence synthesis shows that while there is some low-quality evidence for the effect and timing of multilingual vaccination campaigns that involve the community, there is little high-quality research on housing standards or operational standards needed to prevent respiratory infections in this population. Similar to other reviews of refugee and hard-to-reach populations for tuberculosis [29,41], vaccine-preventable diseases [79] and respiratory infections [8], we conclude that it is important to incorporate cultural aspects in informational and community-involving campaigns and that more controlled operational research is needed. New methods of ensuring informed consent for early vaccinations must also be established.…”

Interventions to help people understand community immunity: A systematic review

“…In addition, we retrieved further studies by searching the references of relevant review articles [10][11][12][13][14][15][16][17][18][19], by a hand search of articles cited by or cited in the included articles, and by consulting with 33 experts through professional networks of co-authors for suggestions of relevant published or unpublished literature or web-based interventions missed during our search.…”

Determinants of healthcare seeking for childhood illnesses among caregivers of under-five children in urban slums in Malawi: a population-based cross-sectional study

“…Justifiably, ensuring that health services reach the rural population has been one of the policy priorities of Malawi's Ministry of Health [15][16][17]. However, evidence is abound suggesting that certain urban population groups, such as the urban poor living in urban slums, characterised by overcrowding; inadequate access to safe water; sanitation; insecurity of tenure; poor housing and inadequate public services experience a health disadvantage [18][19][20][21][22][23][24][25].…”