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  • Analyses such as those used

    2019-06-12

    Analyses such as those used by Burke and colleagues rely on periodic cross-sectional surveys that are not linked to available or civic registration and vital statistics databases. These surveys are also limited by the inevitable time lag between analyses and feedback to health systems and policy makers, especially at the local level. Although vital registration systems might take a long time to reach all at-risk populations in LMICs, innovative options could potentially be developed for data collection and feedback, which might in turn make small unit analysis possible. The usefulness of community-based health workers for data collection and monitoring of mortality trends in Ethiopia is one such example and should pave the way for the development of similar low cost and effective systems for monitoring and evaluation. This data revolution is a crucial part of the move towards greater transparency and accountability set out in the Sustainable Development Goals.
    Children younger than 5 years are in the age group most vulnerable to infection with influenza virus, and these infections contribute substantially to the overall harm caused to the general population. Thus, the development of safe and efficacious vaccines suitable for this age group is a high public health priority. The vulnerability of young children becomes even more obvious in densely populated, low-resource countries with poor health-care systems and no established influenza melanotropin cost policies. Much interest has been paid to the performance of live attenuated melanotropin cost influenza vaccines (LAIVs) compared with inactivated vaccines in developing countries because LAIVs have higher yields during manufacture, the purification process is simpler, lot release is quicker, and they may be delivered intranasally, removing the need for needles. Russian-backbone LAIV has a long history of development, and it was a great achievement when this technology was licensed to WHO with permission to grant sublicenses to vaccine manufacturers in newly industrialised and developing countries within the framework of the WHO Influenza Vaccine Technology Transfer Project. As a part of this project, the Serum Institute of India, Pune, India, adopted the technology, and its LAIV is now prequalified by WHO. In , two studies are reported by W Abdullah Brooks and colleagues and John C Victor and colleagues that present the safety and efficacy results for an Indian-made Russian-backbone LAIV given to young children in Bangladesh and Senegal. Both studies were randomised controlled trials, and both confirmed LAIV safety in children aged 2–5 years. Reactions within 7 days of vaccine receipt were mostly mild, and were most commonly cough (6·5% in Bangladesh and 9·7% in Senegal) and runny nose (6·1% and 17·1%). This good safety profile is in concordance with the findings in an earlier safety and immunogenicity LAIV trial done in Bangladesh in 2012. Also of note is that Abdullah and colleagues\' study in Bangladesh included a large cohort of children with history of asthma and wheezing, and no increase in any safety signals was seen in these children following the receipt of the LAIV. The vaccine efficacy differed notably between the two countries, from 57·5% (95 CI 43·6 to 68·0) in Bangladesh to 0·0% (–26·4 to 20·9) in Senegal, despite use of the same LAIV lot. Attack rates for H1N1pdm09 viruses were high in both studies, and the absence of vaccine efficacy in Senegal was mainly due to the lack of protection against this strain, which was the predominant vaccine-matched strain, and high circulation of mismatched influenza B strains during the trial. Victor and colleagues could find no clear explanation for the discrepancy in vaccine efficacy between study sites. I suggest that the most reasonable explanations would be the low temperature stability of the H1N1dpm09 LAIV component. The A/California strain has 47Glu residue in the haemagglutinin 2 subunit that renders the virus unstable. Although the shelf life and the cold chain of the vaccine had been monitored rigorously by the manufacturer, a very hot environment in Senegal might have negatively affected the infectivity of the H1N1dpm09 component. Immunisation in an air-conditioned environment might help to maintain virus infectivity.