Implementation of maternal influenza immunization in El Salvador: Experiences and lessons learned from a mixed-methods study.

INTRODUCTION: The World Health Organization (WHO) recommends that countries prioritize pregnant women for influenza vaccination, yet few low- or middle-income countries (LMICs) have implemented maternal influenza immunization programs. To inform vaccine decision-making and operational planning in LMICs, there is a need to document and share experiences from countries that provide seasonal influenza vaccine to pregnant women, particularly those with high coverage, like El Salvador. METHODS: In 2015 and 2016, PATH and country researchers conducted a mixed-methods study to document the experience and lessons learned from maternal influenza immunization delivery and acceptance in El Salvador as part of a collaborative effort between WHO and PATH. Researchers conducted focus group discussions, semi-structured interviews, antenatal clinic exit interviews, and key informant interviews with 326 participants from two municipalities in each of the country's three regions. Respondents included pregnant and recently pregnant women, family members, community leaders, health personnel, public health managers and partners, and policymakers. RESULTS: Factors perceived as positively influencing maternal influenza immunization delivery and acceptance in El Salvador include the use of multiple vaccine delivery strategies, targeted education and community engagement efforts, and a high degree of trust between the community and health care providers. Influenza vaccine acceptance by pregnant women is high and has improved over time, largely attributed to education targeting health care advisors. Perceived challenges to pregnant women receiving health care and vaccination include the need for permission to attend services and limited access to health services in insecure areas related to the presence of criminal gang activity. CONCLUSIONS: We identified approaches and barriers perceived to affect maternal influenza vaccine delivery in El Salvador. This information will be useful to public health decision-makers and implementers in El Salvador and other countries considering introduction of new maternal vaccines or striving to increase coverage of vaccines currently provided.

Catching-up with pentavalent vaccine: Exploring reasons behind lower rotavirus vaccine coverage in El Salvador.

Rotavirus vaccine was introduced in El Salvador in 2006 and is recommended to be given concomitantly with DTP-HepB-Haemophilus influenzae type b (pentavalent) vaccine at ages 2 months (upper age limit 15 weeks) and 4 months (upper age limit 8 months) of age. However, rotavirus vaccination coverage continues to lag behind that of pentavalent vaccine, even in years when national rotavirus vaccine stock-outs have not occurred. We analyzed factors associated with receipt of oral rotavirus vaccine among children who received at least 2 doses of pentavalent vaccine in a stratified cluster survey of children aged 24-59 months conducted in El Salvador in 2011. Vaccine doses included were documented on vaccination cards (94.4%) or in health facility records (5.6%). Logistic regression and survival analysis were used to assess factors associated with vaccination status and age at vaccination. Receipt of pentavalent vaccine by age 15 weeks was associated with rotavirus vaccination (OR: 5.1; 95% CI 2.7, 9.4), and receipt of the second pentavalent dose by age 32 weeks was associated with receipt of two rotavirus vaccine doses (OR: 5.0; 95% CI 2.1-12.3). Timely coverage with the first pentavalent vaccine dose was 88.2% in the 2007 cohort and 91.1% in the 2008 cohort (p=0.04). Children born in 2009, when a four-month national rotavirus vaccine stock-out occurred, had an older median age of receipt of rotavirus vaccine and were less likely to receive rotavirus on the same date as the same dose of pentavalent vaccine than children born in 2007 and 2008. Upper age limit recommendations for rotavirus vaccine administration contributed to suboptimal vaccination coverage. Survey data suggest that late rotavirus vaccination and co-administration with later doses of pentavalent vaccine among children born in 2009 helped increase rotavirus vaccine coverage following shortages.

Routine childhood vaccination programme coverage, El Salvador, 2011-In search of timeliness.

While assessing immunization programmes, not only vaccination coverage is important, but also timely receipt of vaccines. We estimated both vaccination coverage and timeliness, as well as reasons for non-vaccination, and identified predictors of delayed or missed vaccination, for vaccines of the first two years of age, in El Salvador. We conducted a cluster survey among children aged 23-59 months. Caregivers were interviewed about the child immunization status and their attitudes towards immunization. Vaccination dates were obtained from children immunization cards at home or at health facilities. We referred to the 2006 vaccination schedule for children below two years: one dose of BCG (Bacillus Calmette-Guérin) at birth; rotavirus at two and four months; three doses of pentavalent - DTP (diphtheria-tetanus-pertussis), hepatitis B, and Haemophilus influenzae type b (Hib) - and of oral poliomyelitis vaccine (polio) at two, four, and six months; first MMR (measles-mumps-rubella) at 12 months; and first boosters of DTP and OPV at 18 months. Timeliness was assessed with Kaplan-Meier analysis; Cox and logistic regression were used to identify predictors of vaccination. We surveyed 2550 children. Coverage was highest for BCG (991%; 95% CI: 98.8-99.5) and lowest for rotavirus, especially second dose (86.3%; 95% CI: 84.2-88.4). The first doses of MMR and DTP had 991% (95% CI: 98.5-99.6) and 977% (95% CI: 970-985), respectively. Overall coverage was 837% (95% CI: 81.4-86.0); 96.4% (95% CI: 95.4-97.5), excluding rotavirus. However, only 26.7% (95% CI: 24.7-28.8) were vaccinated within the age interval recommended by the Expanded Programme on Immunization. Being employed and using the bus for transport to the health facility were associated with age-inappropriate vaccinations; while living in households with only two residents and in the "Paracentral", "Occidental", and "Oriental" regions was associated with age-appropriate vaccinations. Vaccination coverage was high in El Salvador, but general timeliness and rotavirus uptake could be improved.