Effect of ten-valent pneumococcal conjugate vaccine on invasive pneumococcal disease and nasopharyngeal carriage in Kenya: a longitudinal surveillance study.

BACKGROUND: Ten-valent pneumococcal conjugate vaccine (PCV10), delivered at 6, 10, and 14 weeks of age was introduced in Kenya in January, 2011, accompanied by a catch-up campaign in Kilifi County for children aged younger than 5 years. Coverage with at least two PCV10 doses in children aged 2-11 months was 80% in 2011 and 84% in 2016; coverage with at least one dose in children aged 12-59 months was 66% in 2011 and 87% in 2016. We aimed to assess PCV10 effect against nasopharyngeal carriage and invasive pneumococcal disease (IPD) in children and adults in Kilifi County. METHODS: This study was done at the KEMRI-Wellcome Trust Research Programme among residents of the Kilifi Health and Demographic Surveillance System, a rural community on the Kenyan coast covering an area of 891 km2. We linked clinical and microbiological surveillance for IPD among admissions of all ages at Kilifi County Hospital, Kenya, which serves the community, to the Kilifi Health and Demographic Surveillance System from 1999 to 2016. We calculated the incidence rate ratio (IRR) comparing the prevaccine (Jan 1, 1999-Dec 31, 2010) and postvaccine (Jan 1, 2012-Dec 31, 2016) eras, adjusted for confounding, and reported percentage reduction in IPD as 1 minus IRR. Annual cross-sectional surveys of nasopharyngeal carriage were done from 2009 to 2016. FINDINGS: Surveillance identified 667 cases of IPD in 3 211 403 person-years of observation. Yearly IPD incidence in children younger than 5 years reduced sharply in 2011 following vaccine introduction and remained low (PCV10-type IPD: 60·8 cases per 100 000 in the prevaccine era vs 3·2 per 100 000 in the postvaccine era [adjusted IRR 0·08, 95% CI 0·03-0·22]; IPD caused by any serotype: 81·6 per 100 000 vs 15·3 per 100 000 [0·32, 0·17-0·60]). PCV10-type IPD also declined in the post-vaccination era in unvaccinated age groups (<2 months [no cases in the postvaccine era], 5-14 years [adjusted IRR 0·26, 95% CI 0·11-0·59], and ≥15 years [0·19, 0·07-0·51]). Incidence of non-PCV10-type IPD did not differ between eras. In children younger than 5 years, PCV10-type carriage declined between eras (age-standardised adjusted prevalence ratio 0·26, 95% CI 0·19-0·35) and non-PCV10-type carriage increased (1·71, 1·47-1·99). INTERPRETATION: Introduction of PCV10 in Kenya, accompanied by a catch-up campaign, resulted in a substantial reduction in PCV10-type IPD in children and adults without significant replacement disease. Although the catch-up campaign is likely to have brought forward the benefits by several years, the study suggests that routine infant PCV10 immunisation programmes will provide substantial direct and indirect protection in low-income settings in tropical Africa. FUNDING: Gavi, The Vaccine Alliance and The Wellcome Trust of Great Britain.

Evaluating the role of breastfeeding peer supporters' intervention on the inpatient management of malnourished infants under 6 months in Kenyan public hospitals.

BACKGROUND: The 2013 WHO guidelines for nutritional rehabilitation of malnourished infants under six months (u6m) focus on inpatient re-establishment of exclusive breastfeeding and recommends discharge when infant is gaining weight on breastmilk alone. Guided by a breastfeeding support tool, breastfeeding peer supporters (BFPS) can support implementation of these guideline by providing continuous individualised breastfeeding counselling to mothers of malnourished infants u6m. Recording and sharing information plays an important role in shaping in-patient care but little is known about recording practices for inpatient nutrition rehabilitation of infants u6m or how such practices affect care. We set out to explore introduction of BFPS into hospitals, and how it shaped the recording and practices of care for acutely malnourished infants u6m. METHODS: We applied a descriptive, exploratory design involving a pre and during intervention audit of the infant u6m inpatient records in two hospitals in Kenya, as well as pre- and post-intervention in-depth interviews with health workers involved in the care of admitted infants u6m. We developed an audit tool and used it to extract routine data on patient information from hospital records. Data were entered into a REDCap database and analyzed using STATA 17.0 software. We conducted thirty in-depth interviews with health workers exploring their care practices and their perceived effect of the presence of the BFPS on health workers treatment practices. We analysed interview data using thematic framework approach. RESULTS: A total of 170 and 65 inpatient files were available for the audit during the pre- and post-intervention period respectively. The presence of the BFPS seemed to have encouraged the recording of (i) breastfeeding status upon admission, (ii) breastfeeding management plan and (iii) reporting of its implementation and progress during treatment. The breastfeeding peer support intervention had a positive impact on breastfeeding recording and reporting practices. Health workers reported that the BFPS facilitated the recording of observed breastfeeding data and how their records influenced final inputs of breastfeeding support provided in the inpatient file. CONCLUSIONS: Guideline implementation tools facilitate effective application of guidelines and should accompany any guideline formulation process and have their effectiveness at recording and monitoring progress evaluated.

Knowledge of, and attitudes to giving expressed breastmilk to infants in rural coastal Kenya; focus group discussions of first time mothers and their advisers.

BACKGROUND: The World Health Organization (WHO)/UNICEF Baby-Friendly Hospital Initiative step number five of the "Ten steps to successful breastfeeding" states "Show mothers how to breastfeed and how to maintain lactation even if they should be separated from their infants." Urban mothers in Nairobi have low rates of exclusive breastfeeding after returning to work but there are no published data on rural Kenya mothers' infant feeding practices when working or schooling away from home. METHODS: We explored knowledge of, and attitudes to, the practice of giving expressed breastmilk in a mixed methods observational study of breastfeeding in rural Kenyan mothers. Fifty mothers with newborns, identified by nurses and community health workers, were asked questions about their experiences of breastfeeding and who they had sought or received advice from on breastfeeding. Focus group discussions, one with community health workers, and four each with mothers and their named advisers were held. Recordings were analyzed using a thematic framework approach. RESULTS: The main themes were: the baby's right to feed from the breast, lack of knowledge about expressing and giving breastmilk, negative attitudes towards expressed breastmilk, and traditional customs for disposing of expressed breast milk. Most participants did not have any experience of giving expressed breastmilk to infants. They described practices of expressing and discarding milk when the mother or baby was ill, to relieve discomfort from engorgement or after the baby had died. CONCLUSIONS: Feeding expressed breastmilk to infants is a new concept in this context. Promotion of, and training in this practice would help mothers to maintain their milk supply when away from their babies and benefit the infants of working and schoolgirl mothers.

"When you give birth you will not be without your mother" A mixed methods study of advice on breastfeeding for first-time mothers in rural coastal Kenya.

BACKGROUND: Exclusive breastfeeding for the first 6 months of life is currently recommended by the World Health Organization, but mixed feeding earlier than this commonly occurs in rural coastal Kenya. Mothers may receive conflicting advice on breastfeeding from various sources including health workers, relatives and community members. We aimed to find out how first-time mothers learn to breastfeed, who advises them on infant feeding and what advice they obtain in case of any breastfeeding problems. METHODS: To identify advisers, a questionnaire on socio-demographic status, place of delivery, household members, education and help received on breastfeeding, breastfeeding problems, name of advisers and their relationship to the mothers was administered to 50 new first-time mothers in Jaribuni, Kilifi (population approximately 18,000). Summary statistics were obtained using frequencies, medians and interquartile ranges (IQR). Focus group discussions (FGDs) were held amongst 4 groups of mothers who had answered questionnaires; 4 groups of their named advisers; and 1 group of community health workers in order to explore breastfeeding practices, problems and advice given. FGDs were analysed by thematic framework analysis. RESULTS: First-time mothers were young (median age 18, IQR 17-21, range 14-26 years) and 42 % were single. Living in extended families was the norm and married women lived with their husband's family. All had a female family member or neighbour helping with childcare in the perinatal period. The main advisers on breastfeeding were their mother or older female members of their husband's family. Married first-time mothers felt obliged to follow their mother-in-law's advice to maintain good relationships and show respect within the household. Breastfeeding problems were reported by 80 % of respondents. Nipple pain (56 %) was the most reported problem, then breast engorgement (48 %) and insufficient milk supply (38 %). Most problems were treated at home without consultation with health workers. Concerns were raised about co-sleeping, breastfeeding whilst lying down, and insufficient milk supply. Advisers would like more information on breastfeeding in order to help mothers. CONCLUSIONS: Interventions to increase knowledge of, and facilitate optimal breastfeeding practices in first-time mothers should include those family members who advise and assist with childcare around the time of delivery.

Maternal colonization with Streptococcus agalactiae and associated stillbirth and neonatal disease in coastal Kenya.

Streptococcus agalactiae (group B streptococcus, GBS) causes neonatal disease and stillbirth, but its burden in sub-Saharan Africa is uncertain. We assessed maternal recto-vaginal GBS colonization (7,967 women), stillbirth and neonatal disease. Whole-genome sequencing was used to determine serotypes, sequence types and phylogeny. We found low maternal GBS colonization prevalence (934/7,967, 12%), but comparatively high incidence of GBS-associated stillbirth and early onset neonatal disease (EOD) in hospital (0.91 (0.25-2.3)/1,000 births and 0.76 (0.25-1.77)/1,000 live births, respectively). However, using a population denominator, EOD incidence was considerably reduced (0.13 (0.07-0.21)/1,000 live births). Treated cases of EOD had very high case fatality (17/36, 47%), especially within 24 h of birth, making under-ascertainment of community-born cases highly likely, both here and in similar facility-based studies. Maternal GBS colonization was less common in women with low socio-economic status, HIV infection and undernutrition, but when GBS-colonized, they were more probably colonized by the most virulent clone, CC17. CC17 accounted for 267/915 (29%) of maternal colonizing (265/267 (99%) serotype III; 2/267 (0.7%) serotype IV) and 51/73 (70%) of neonatal disease cases (all serotype III). Trivalent (Ia/II/III) and pentavalent (Ia/Ib/II/III/V) vaccines would cover 71/73 (97%) and 72/73 (99%) of disease-causing serotypes, respectively. Serotype IV should be considered for inclusion, with evidence of capsular switching in CC17 strains.

Population effect of 10-valent pneumococcal conjugate vaccine on nasopharyngeal carriage of Streptococcus pneumoniae and non-typeable Haemophilus influenzae in Kilifi, Kenya: findings from cross-sectional carriage studies.

BACKGROUND: The effect of 7-valent pneumococcal conjugate vaccine (PCV) in developed countries was enhanced by indirect protection of unvaccinated individuals, mediated by reduced nasopharyngeal carriage of vaccine-serotype pneumococci. The potential indirect protection of 10-valent PCV (PCV10) in a developing country setting is unknown. We sought to estimate the effectiveness of introduction of PCV10 in Kenya against carriage of vaccine serotypes and its effect on other bacteria. METHODS: PCV10 was introduced into the infant vaccination programme in Kenya in January, 2011, accompanied by a catch-up campaign in Kilifi County for children aged younger than 5 years. We did annual cross-sectional carriage studies among an age-stratified, random population sample in the 2 years before and 2 years after PCV10 introduction. A nasopharyngeal rayon swab specimen was collected from each participant and was processed in accordance with WHO recommendations. Prevalence ratios of carriage before and after introduction of PCV10 were calculated by log-binomial regression. FINDINGS: About 500 individuals were enrolled each year (total n=2031). Among children younger than 5 years, the baseline (2009-10) carriage prevalence was 34% for vaccine-serotype Streptococcus pneumoniae, 41% for non-vaccine-serotype Streptococcus pneumoniae, and 54% for non-typeable Haemophilus influenzae. After PCV10 introduction (2011-12), these percentages were 13%, 57%, and 40%, respectively. Adjusted prevalence ratios were 0·36 (95% CI 0·26-0·51), 1·37 (1·13-1·65), and 0·62 (0·52-0·75), respectively. Among individuals aged 5 years or older, the adjusted prevalence ratios for vaccine-serotype and non-vaccine-serotype S pneumoniae carriage were 0·34 (95% CI 0·18-0·62) and 1·13 (0·92-1·38), respectively. There was no change in prevalence ratio for Staphylococcus aureus (adjusted prevalence ratio for those <5 years old 1·02, 95% CI 0·52-1·99, and for those ≥5 years old 0·90, 0·60-1·35). INTERPRETATION: After programmatic use of PCV10 in Kilifi, carriage of vaccine serotypes was reduced by two-thirds both in children younger than 5 years and in older individuals. These findings suggest that PCV10 introduction in Africa will have substantial indirect effects on invasive pneumococcal disease. FUNDING: GAVI Alliance and Wellcome Trust.