Infectious disease is the main thing that kills people. Some of the greatest improvements to human health have involved improvements in our understanding and control of germs - from John Snow's pioneering work on cholera in the 19th century to the eradication of smallpox in the 20th century. The 21st century sees a new set of challenges in the understanding and control of infections - while the eradication of polio progresses, we see new influenza strains causing or threatening pandemics, the continued progression of HIV and a massive health burden of often simply but expensively preventable diseases in the developing world.Epidemiology - the science of looking for significant patterns in cases of disease - has always been at the heart of controlling infectious diseases, and mathematics has always been central epidemiology.This project applies advanced mathematics to the science of epidemiology, making use of the large datasets and modern computational resources that are available. New insights about the structure of complex systems offer the promise of making massive advances in this field, through enhanced understanding of transmission routes of infection, risk factors and changes in the disease over time. These insights can in turn be combined with mathematical methods to design optimised interventions against infection so that diseases can be controlled in the most effective way.

For the first time, in 2013, the WHO guidelines for treating children with Severe Acute Malnutrition (SAM) included guidance on how to diagnose and treat SAM in infants aged below 6 months. The treatment guidelines for infants under 6 months focused on inpatient treatment and recommended that admitted infants with SAM be supported to re-establish exclusive breastfeeding before they can be discharged. The recommendation was based mainly on programmatic reports and a few studies that had shown that lactation failure is common among infants with SAM, and that re-establishing breastfeeding among infants being treated for SAM is possible using re-lactation techniques such as supplementary suckling. However, since none of the studies followed infants up after discharge, we still do not know i) if exclusive breastfeeding was retained after discharge; ii) if retaining exclusive breastfeeding after discharge is sufficient for nutritional recovery and iii) if additional breastfeeding support offered to mothers of discharged infants would be beneficial. The proposed study is aimed at generating important information to develop a trial to establish the effectiveness of home-based breastfeeding support to mothers of infants discharged from SAM treatment on survival and growth. The main aim of the proposed study is to i) establish the breastfeeding retention rate among infants under 6 months discharged from SAM treatment within the current strategies that are without a specific post discharge breastfeeding support; and ii) establish whether among infants retaining exclusive breastfeeding, breastmilk alone is sufficient for nutritional recovery. This information will form the baseline data from where any success of any applied intervention will be measured. Hence the findings from this study will strengthen the calculations of the sample size required to show an improvement in the outcomes due to an intervention. In addition, the study will provide insight on the acceptability and sustainability of using peer breastfeeding supporters commonly used to encourage breastfeeding in preterm neonates for infants with SAM. It will also provide information on the optimal trial follow-up strategy that could be applied successfully for this group of participants. Apart from providing information for trial development, the study findings will by themselves provide data to previously identified research gap. Within the 2013 updated WHO guidelines on management of SAM in children, http://apps.who.int/iris/bitstream/10665/95584/1/9789241506328_eng.pdf (page 66) the question of how breastfeeding is most effectively established is raised. Our study intends to optimize the WHO inpatient treatment guidelines and will in the process develop a step-by-step re-lactation protocol that would be applicable for resource poor settings. Recently, using the well developed and highly recommended Child Health and Nutrition Research Initiative (CHNRI) methodology, researchers, developmental partners and other stakeholders including UN agencies identified that research into the components of a package care for outpatient care as one of the top research priorities for infants with SAM (Angood, McGrath et al. 2015). Findings from the proposed study will provide baseline information useful in designing and testing a package for outpatient care.

Infectious disease is the main thing that kills people. Some of the greatest improvements to human health have involved improvements in our understanding and control of germs - from John Snow's pioneering work on cholera in the 19th century to the eradication of smallpox in the 20th century. The 21st century sees a new set of challenges in the understanding and control of infections - while the eradication of polio progresses, we see new influenza strains causing or threatening pandemics, the continued progression of HIV and a massive health burden of often simply but expensively preventable diseases in the developing world.Epidemiology - the science of looking for significant patterns in cases of disease - has always been at the heart of controlling infectious diseases, and mathematics has always been central epidemiology.This project applies advanced mathematics to the science of epidemiology, making use of the large datasets and modern computational resources that are available. New insights about the structure of complex systems offer the promise of making massive advances in this field, through enhanced understanding of transmission routes of infection, risk factors and changes in the disease over time. These insights can in turn be combined with mathematical methods to design optimised interventions against infection so that diseases can be controlled in the most effective way.

Improving child health requires primary prevention, quality health services and community action to address the underlying drivers of health and wellbeing. Whilst there is recognition that the health system encompasses both the suppliers of policy, services, and interventions, and the communities and households intended to benefit from them; in health systems research the focus has primarily been on the supply-side with little attention given to the demand-side of this equation. Gender roles and relations play an important role in child health and nutritional status. In many sub-Saharan African (sSA) settings, childcare and health is predominantly a female domain with men largely absent or only involved in perceived severe or serious cases. Similarly, intentionally or unintentionally, child health programmes in sSA countries predominantly focus on women. While women are perceived as responsible for children, paradoxically they must negotiate decision-making and resources with other family members, including men. By exclusively focusing on women without considering family dynamics or the broader social context, these programmes may inadvertently reinforce harmful gender divisions and practices related to child health and nutrition. Evidence suggests that programmes targeting women might be more effective if men's roles are considered and transformed to affirm more equitable gender relations. For example, in the 'Men in Maternity' programme in New Delhi, India, husbands were encouraged to play an active role in their wives' antenatal and post-natal care with improved outcomes in the intervention compared to the control groups. Similarly, the IMAGE intervention in Limpopo South Africa used a participatory approach to engage men and challenge behaviours in relation to intimate partner violence and HIV transmission; resulting in a significant reduction in the risk of physical and sexual violence by an intimate partner even up to two years after introduction of the intervention. Informal settlements (referred to colloquially as 'slums') house a significant proportion of the world's urban population particularly in low- and middle-income countries; with this number set to rise with increasing urbanization. Throughout their life-course, these populations suffer from disproportionately higher burden of illness compared to the general population. In Kenya where this work will be undertaken, studies show that slums in the capital city of Nairobi have higher child and under-five mortality rates compared to the national, urban and rural averages with long and complex pathways to seeking care; frequently involving the use of informal systems of healthcare prior to, or concurrently with, engaging formal health facilities. Furthermore, following treatment in the formal health system, ill or recovering children are 'discharged back' into their homes and communities. Without proper understanding of the complexities and dynamics operating at the household and community levels, hospital-initiated interventions are likely to be less effective and sustainable. Focusing on the demand-side of the health system, the proposed work seeks to answer if and how participatory approaches can strengthen male involvement in child health and nutrition for better outcomes. Specifically:1) To understand men's and women's perspectives of the actual, desired and perceived role of men in child health, and related barriers and facilitators; and 2) Use an in-depth participatory approach to engage men and other stakeholders in co-creating a context-specific, feasible, and scalable male engagement intervention package for improved and more responsive health service delivery.

Acute malnutrition among infants aged under 6 months is a major public health problem. Recent reports indicate that globally, 8.5 million infants under 6 months suffer from moderate or severe acute malnutrition. Malnourished infants are significantly more likely to be hospitalized and die from treatable infectious diseases than non-malnourished infants. Studies have shown that the majority of these infants (up to 90%) are not exclusively breastfed, even though evidence suggests that exclusive breastfeeding is particularly important for recovery and survival among this group. To improve the nutritional status of hospitalized malnourished infants, the World Health Organization (WHO) recommends the re-establishment of exclusive breastfeeding. However, challenges such as shortages of appropriately trained health workers and lack of information on "how" exclusive breastfeeding can most effectively be re-established have hampered the effective implementation of these recommendations in many low-income settings, including Kenya. In Kenya, as elsewhere in sub-Saharan Africa, breastfeeding lay peer supporters (mothers from the local community trained in breastfeeding assistance) are used to promote and support exclusive breastfeeding among mothers of healthy infants in their communities. We are currently undertaking a study (IBAMI) in a hospital in Kenya investigating the maintenance of exclusive breastfeeding amongst infants recovering from acute malnutrition and infection after they have been discharged from hospital. We have introduced breastfeeding peer supporters in the hospital to help the health workers implement the WHO guidelines. With the support of study staff and funding, peer supporters have become a central part of the inpatient treatment management team undertaking tasks integral to the breastfeeding treatment plan. Our experiences from the IBAMI study suggest that breastfeeding lay peer supporters might be an effective strategy for enhancing the implementation of the WHO guidelines. However, the supportive financial and management conditions provided by the IBAMI study are unlikely to be repeated in resource constrained hospital settings in Kenya and routine implementation would involve introducing a new low skilled, as yet unrecognised cadre into complex, multi-professional hospital environments. To understand when, where and how breastfeeding peer supporters might be integrated into the routine treatment of inpatient malnourished infants, we propose to undertake a pilot study investigating the health system factors that are likely to enhance or constrain the use of breastfeeding peer supporters in the implementation the WHO guidelines for nutrition rehabilitation of inpatient infants under routine conditions in two public hospitals in Kenya. To gauge policy level interest in the approach, we will identify and engage with key policy makers at national and county levels in Kenya; determine their views on employing lay peer supporters in a hospital setting and discuss potential barriers and facilitators to implementation. To assess the feasibility of using breastfeeding peer supporters, we will collaborate with the Kilifi County Ministry of Health (MoH), to identify two hospitals and in each we will work with the hospital management team, frontline health workers, UNICEF and National MoH to develop and agree on a strategy for the implementation of a breastfeeding peer supporters' intervention. During strategy implementation, quarterly meetings to review progress and identify factors enhancing or constraining the integration process will be held. After 12 months, we will estimate the costs of implementing the strategy and hold review meetings and interviews in each of the two hospital to assess perceptions of its feasibility, acceptability and sustainability. The findings from this study will generate new knowledge to improve the hospital management and treatment of malnourished infants under 6 months.