Temporal decline in diarrhea episodes and mortality in Kiribati children two years following rotavirus vaccine introduction, despite high malnutrition rates: a retrospective review.

BACKGROUND: Kiribati introduced rotavirus vaccine in 2015. To estimate the impact of rotavirus vaccine on acute gastroenteritis (AGE) and severe acute malnutrition (SAM) among children under 5 in Kiribati, a retrospective review of inpatient and outpatient AGE and hospitalized SAM was undertaken. METHODS: Inpatient data for admissions and hospital deaths due to AGE, SAM and all-causes were collected for children under 5 from all hospitals on the main island, Tarawa, from January 2010-December 2013 (pre-rotavirus vaccine) and January 2016-September 2017 (post-rotavirus vaccine). National outpatient diarrhea data were collected from January 2010 to August 2017 for under 5. An interrupted time-series analysis was undertaken to estimate the effect of rotavirus vaccine on the rates of inpatient and outpatient AGE, inpatient SAM; and inpatient case fatality rates for AGE and SAM, were calculated pre- and post-rotavirus vaccine introduction. RESULTS: The incidence rate of AGE admissions from Tarawa and national AGE outpatient presentations significantly declined by 37 and 44%, respectively, 2 years following rotavirus vaccine introduction. There was a significant decline in the percentage of AGE contributing to all-cause under 5 admissions (12·8% vs. 7·2%, p < 0·001) and all-cause under-five mortality (15·9% vs. 5·7%, p = 0·006) pre- and post-rotavirus vaccine introduction. The estimated incidence rate of inpatient SAM decreased by 24% in under 5 s, 2 years following rotavirus vaccine introduction. CONCLUSIONS: AGE morbidity and mortality and hospitalized SAM rates have declined following rotavirus vaccine introduction in Kiribati children.

Improving hepatitis B birth dose coverage through village health volunteer training and pregnant women education.

Hepatitis B is highly endemic in the Republic of Kiribati, while the coverage of timely birth dose vaccination, the primary method shown to prevent mother-to-child transmission of hepatitis B virus, was only 66% in 2014. Children born at home are especially at high risk, as they have limited access to timely birth dose (i.e. within 24 h) vaccination. To improve birth dose coverage, a project to improve linkages between village health volunteers and health workers and educate pregnant women on hepatitis B vaccination was carried out in 16 communities with low birth dose coverage in Kiribati from November 2014 to May 2015. After project completion, the coverage of timely birth dose administration increased significantly both in the densely populated capital region of South Tarawa (from 89% to 95%, p=0.001) and the Outer Islands (from 57% to 83%, p<0.001). The coverage of timely birth dose administration among infants born at home increased significantly from 70% to 84% in South Tarawa (p=0.001) and from 49% to 75% in the Outer Islands (p<0.001). Timely birth dose was associated with being born in a hospital, being born during the study period and caregivers having developed an antenatal birth dose plan. The project demonstrates a successful model for improving hepatitis B vaccine birth dose coverage that could be adopted in other areas in Kiribati as well as other similar settings.

Progress towards achieving hepatitis B control in the Cook Islands, Niue, Tokelau, and Kiribati.

BACKGROUND: Hepatitis B virus (HBV) is highly endemic in many of the Pacific Island countries. Four island countries-Cook Islands, Kiribati, Niue, and Tokelau-sought to evaluate the success of their hepatitis B vaccination programs by conducting nationally representative serosurveys among children born post-vaccine introduction. METHODS: Cook Islands, Niue, and Tokelau conducted school-based census serosurveys because of small populations. The Cook Islands tested children in second grade; Niue tested children in early childhood education through sixth grade; and Tokelau tested children in first through sixth grades. Because Kiribati has a much larger birth cohort, it conducted a one-stage stratified serosurvey among first grade students. All four countries tested children using the Alere Determine™ rapid point of care hepatitis B surface antigen (HBsAg) test. RESULTS: In the three smaller countries, no children were seropositive for HBsAg (0/245 Cook Island students, 0/183 Niuean students, 0/171 Tokelau students). In Kiribati, 39 (3.3%, 95% confidence interval 2.4-4.6%) of 1249 students were HBsAg positive. Vaccination data collected in the Cook Islands and Tokelau showed high vaccination coverage in both countries with ⩾95% birth dose coverage and 100% 3-dose coverage. CONCLUSIONS: The Cook Islands, Niue, and Tokelau have made remarkable progress in establishing strong vaccination programs and towards decreasing the burden of hepatitis B among children. Kiribati still needs to improve vaccination coverage to achieve the <1% HBsAg target established by the World Health Organization Western Pacific Region.