Pneumococcal conjugate vaccine introduction in Latin America and the Caribbean: progress and lessons learned.

In Latin America and the Caribbean, pneumococcus has been estimated to cause 12,000-28,000 deaths, 182,000 hospitalizations, and 1.4 million clinic visits annually. Countries in the Americas have been among the first developing nations to introduce pneumococcal conjugate vaccines into their Expanded Programs on Immunization, with 34 countries and territories having introduced these vaccines as of September 2015. Lessons learned for successful vaccine introduction include the importance of coordination between political and technical decision makers, adjustments to the cold chain prior to vaccine introduction, and the need for detailed plans addressing the financial and technical sustainability of introduction. Though many questions on the Pneumococcal Conjugate Vaccine remain unanswered, the experience of the Americas suggests that the vaccines can be introduced quickly and effectively.

Lessons learned from the development of a new methodology to assess missed opportunities for vaccination in Latin America and the Caribbean.

The Pan American Health Organization recently developed a practical guide for evaluating missed opportunities for vaccination among children aged <5 years. A missed opportunity occurs when an individual eligible for vaccination has contact with a health facility and does not receive a needed vaccine, despite having no contraindications. In this article, we discuss the strengths and limitations of this new methodology and present lessons learned from recent studies on undervaccination in Latin America. Our findings should be useful to countries embarking on assessing the magnitude and the causes of missed opportunities for vaccination children experience at health facilities.

Understanding the main barriers to immunization in Colombia to better tailor communication strategies.

BACKGROUND: The Expanded Program on Immunization (EPI) in Colombia has made great advances since its inception in 1979; however, by 2010 vaccination coverage rates had been declining. In 2010, the EPI commissioned a nationwide study on practices on immunization, attitudes and knowledge, perceived service quality, and barriers to childhood immunization in order to tailor EPI communication strategies. METHODS: Colombia's 32 geographical departments were divided into 10 regions. Interviewers from an independent polling company administered a survey to 4802 parents and guardians of children aged <5 years in these regions. To better assess barriers to vaccination, the study was designed to have 70% of participants who had children with incomplete vaccination schedules. Explanatory factorial, principal component, and cluster analyses were performed to place participants into a group (segment) representing the primary category of reasons respondents offered for not vaccinating their children. Types of barriers were then compared to other variables, such as service quality, communication preferences, and parental attitudes on vaccination. RESULTS: Although all respondents indicated that vaccines have health benefits, and 4738 (98.7%) possessed vaccination cards for their children, attitudes and knowledge were not always favorable to immunization. Six groups of immunization barriers were identified: 1) factors related to caregivers (24.4%), 2) vaccinators (19.7%), 3) health centers (18.0%), 4) the health system (13.4%), 5) concerns about adverse events (13.1%), and 6) cultural and religious beliefs (11.4%); groups 1, 5 and 6 together represented almost half (48.9%) of users, indicating problems related to the demand for vaccines as the primary barriers to immunization. Differences in demographics, communication preferences, and reported service quality were found among participants in the six groups and among participants in the 10 regions. Additionally, differences between how participants reported receiving information on vaccination and how they believed such information should be communicated were observed. CONCLUSIONS: Better understanding immunization barriers and the users of the EPI can help tailor communication strategies to increase demand for immunization services. Results of the study have been used by Colombia's EPI to inform the design of new communication strategies.

From the parents' perspective: a user-satisfaction survey of immunization services in Guatemala.

BACKGROUND: Immunization coverage levels in Guatemala have increased over the last two decades, but national targets of ≥95% have yet to be reached. To determine factors related to undervaccination, Guatemala's National Immunization Program conducted a user-satisfaction survey of parents and guardians of children aged 0-5 years. Variables evaluated included parental immunization attitudes, preferences, and practices; the impact of immunization campaigns and marketing strategies; and factors inhibiting immunization. METHODS: Based on administrative coverage levels and socio-demographic indicators in Guatemala's 22 geographical departments, five were designated as low-coverage and five as high-coverage areas. Overall, 1194 parents and guardians of children aged 0-5 years were interviewed in these 10 departments. We compared indicators between low- and high-coverage areas and identified risk factors associated with undervaccination. RESULTS: Of the 1593 children studied, 29 (1.8%) were determined to be unvaccinated, 458 (28.8%) undervaccinated, and 1106 (69.4%) fully vaccinated. In low-coverage areas, children of less educated (no education: RR=1.49, p=0.01; primary or less: 1.39, p=0.009), older (aged>39 years: RR=1.31, p=0.05), and single (RR=1.32, p=0.03) parents were more likely to have incomplete vaccination schedules. Similarly, factors associated with undervaccination in high-coverage areas included the caregiver's lack of education (none: RR=1.72, p=0.0007; primary or less: RR=1.30, p=0.05) and single marital status (RR=1.36, p=0.03), as well as the child's birth order (second: RR=1.68, p=0.003). Although users generally approved of immunization services, problems in service quality were identified. According to participants, topics such as the risk of adverse events (47.4%) and next vaccination appointments (32.3%) were inconsistently communicated to parents. Additionally, 179 (15.0%) participants reported the inability to vaccinate their child on at least one occasion. Compared to high-coverage areas, participants in low-coverage areas reported poorer service, longer wait times, and greater distances to health centers. In high-coverage areas, participants reported less knowledge about the availability of services. CONCLUSIONS: Generally, immunization barriers in Guatemala are related to problems in accessing and attaining high-quality immunization services rather than to a population that does not adequately value vaccination. We provide recommendations to aid the country in maintaining its achievements and addressing new challenges.

Vaccine-associated paralytic poliomyelitis in the postelimination era in Latin America and the Caribbean, 1992-2011.

The Americas interrupted the transmission of poliovirus in 1991; most Latin American and Caribbean (LAC) countries rely on the oral polio vaccine (OPV) to maintain elimination. We estimated the risk of vaccine-associated paralytic polio (VAPP) in LAC for 1992-2011. VAPP cases were identified using LAC's acute flaccid paralysis (AFP) surveillance system. VAPP was defined as any AFP case with residual paralysis 60 days following onset that did not have a clear alternative etiology and with isolation of vaccine-strain poliovirus. Recipient VAPP cases were defined as those with paralysis onset 4-40 days following OPV; cases meeting these criteria but with unknown residual paralysis were added. Nonrecipient VAPP cases were defined as those in individuals with an unknown vaccination status, those in individuals who received 0 doses, or those with paralysis onset outside the 4-40-day interval. Of 40 926 AFP cases reported in LAC from 1992-2011, we identified 72 recipient and 119 nonrecipient VAPP cases. The estimated risk of recipient VAPP was 1 case per 3.15 million newborns (95% confidence interval [CI], 1 case per 2.56-4.10 million newborns), and the estimated overall risk was 1 case per 1.19 million newborns (95% CI, 1 case per 1.04-1.39 million newborns). In this multicountry VAPP analysis in a postelimination period, we found that the risk of VAPP in LAC was lower than previously estimated.

Guillain-Barré syndrome in children aged <15 years in Latin America and the Caribbean: baseline rates in the context of the influenza A (H1N1) pandemic.

In light of the influenza A (H1N1) pandemic, the Strategic Advisory Group of Experts on Immunization of the World Health Organization requested that the acute flaccid paralysis surveillance system of Latin American and the Caribbean be used to establish Guillain-Barré syndrome incidence rates. An analysis was conducted of 10,486 acute flaccid paralysis cases diagnosed as Guillain-Barré syndrome from 2000 through 2008 in children aged <15 years in Latin American and the Caribbean countries and territories. The average incidence was 0.82 cases per 100,000 children aged <15 years (range, 0.72-0.90 cases per 100,000 children), with significant differences between northern and southern countries (1.08 vs 0.57 cases per 100,000 children). The acute flaccid paralysis surveillance system represents a useful means of monitoring Guillain-Barré syndrome during the pandemic.