A genomic appraisal of invasive Salmonella Typhimurium and associated antibiotic resistance in sub-Saharan Africa

Invasive non-typhoidal Salmonella (iNTS) disease manifesting as bloodstream infection with high mortality is responsible for a huge public health burden in sub-Saharan Africa. Salmonella enterica serovar Typhimurium (S. Typhimurium) is the main cause of iNTS disease in Africa. By analysing whole genome sequence data from 1303 S. Typhimurium isolates originating from 19 African countries and isolated between 1979 and 2017, here we show a thorough scaled appraisal of the population structure of iNTS disease caused by S. Typhimurium across many of Africa's most impacted countries. At least six invasive S. Typhimurium clades have already emerged, with ST313 lineage 2 or ST313-L2 driving the current pandemic. ST313-L2 likely emerged in the Democratic Republic of Congo around 1980 and further spread in the mid 1990s. We observed plasmid-borne as well as chromosomally encoded fluoroquinolone resistance underlying emergences of extensive-drug and pan-drug resistance. Our work provides an overview of the evolution of invasive S. Typhimurium disease, and can be exploited to target control measures.

Impact of early infant feeding practices on mortality in low birth weight infants from rural Ghana

OBJECTIVE

To assess the impact of early infant feeding practices on low birth weight- (LBW) specific neonatal mortality in rural Ghana.

STUDY DESIGN

A total of 11 787-breastfed babies were born between July 2003 and June 2004 and survived to day 2. Overall, 3411 (30.3%) infants had weight recorded within 48 h. Two hundred and ninety-six (8.7%) infants were <2.5 kg and 15 died in the neonatal period. Associations were examined using multivariate logistic regression.

RESULT

Initiation of breastfeeding after day 1 was associated with a threefold increase in mortality risk (adjusted odds ratio (adjOR) 3.23, 95% confidence interval (95% CI) (1.07-9.82)) in infants aged 2 to 28 days. Prelacteal feeding was associated with a threefold significantly increased mortality risk (adjOR 3.12, 95% CI (1.19-8.22)) in infants aged 2 to 28 days but there was no statistically significant increase in risk associated with predominant breastfeeding (adjOR 1.91, 95% CI (0.60-6.09)). There were no modifications of these effects by birth weight. The sample size was insufficient to allow assessment of the impact of partial breastfeeding.

CONCLUSION

Improving early infant feeding practices is an effective, feasible, low-cost intervention that could reduce early infant mortality in LBW infants in developing countries. These findings are especially relevant for sub-Saharan Africa where many LBW infants are born at home, never taken to a health facility and mortality rates are unacceptably high.