Acid pH limits the persistence of Rhizobium strains in soil, and the nodulation and nitrogen fixation of legumes. To identify acid-tolerant strains, we tested the ability of 45 Rhizobium, Azorhizobium, and Bradyrhizobium strains to produce isolated colonies on agar medium of pH 4.00 to pH 7.00. Only Rhizobium tropici UMR1899 (=CIAT899) grew at pH 4.00 in unbuffered medium, though 6 strains of R. tropici and 3 Bradyrhizobium strains grew at pH 4.25, and 15 strains grew at pH 4.50. Tolerance to acid pH in R. tropici UMR1899 was not an adaptive response, nor was it plasmid mediated, correlated with the production of extracellular polysaccharide, or related to synthesis of polyamines in the cell. When UMR1899 was grown in buffered medium at acid pH, it maintained a ΔpH (measured using 31P-NMR) of up to 1.7 pH units. However, when this strain was subjected to acid shock, it showed only limited ability to regulate cytoplasmic pH in the short term. Cells of UMR1899 accumulated glutamate under pH stress, and were markedly hydrophobic and resistant to the effects of crystal violet, the latter traits raising the possibility that outer membrane composition and structure could also be a factor in pH tolerance.Key words: Rhizobium, pH tolerance, glutamate, hydrophobicity, 31P-NMR.

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Non-communicable diseases (NCDs) represent the primary cause of morbidity and mortality worldwide. Specific attention needs to be given in fragile and crisis-affected contexts, where health systems have even more difficulties in addressing and managing these diseases. Humanitarian actors intervening in crisis situations increasingly include NCD management in the services they support and provide. This review aims at presenting a series of questions that humanitarian agencies could consider when addressing NCDs in humanitarian crises. They include, among others, what conditions to address and for which target population, how to ensure continuity of care, which guidelines and medications to use, and what can be done beyond classical management of NCDs.Research and evidence are lacking on how to address care effectively for NCDs in emergencies. Therefore, advocacy is needed for NCD-oriented research so as to make interventions more effective and sustainable. No government or single agency can address NCDs in humanitarian crises alone. Strong leadership and partnerships between humanitarian actors, health providers, government bodies, research and academic institutions are required. Only a coordinated multi-disciplinary and multi-stakeholder approach will achieve the required impact for affected populations.

The 2015–2017 global migratory crisis saw unprecedented numbers of people on the move and tremendous diversity in terms of age, gender and medical requirements. This article focuses on key emerging public health issues around migrant populations and their interactions with host populations. Basic needs and rights of migrants and refugees are not always respected in regard to article 25 of the Universal Declaration of Human Rights and article 23 of the Refugee Convention. These are populations with varying degrees of vulnerability and needs in terms of protection, security, rights, and access to healthcare. Their health status, initially conditioned by the situation at the point of origin, is often jeopardised by adverse conditions along migratory paths and in intermediate and final destination countries. Due to their condition, forcibly displaced migrants and refugees face a triple burden of non-communicable diseases, infectious diseases, and mental health issues. There are specific challenges regarding chronic infectious and neglected tropical diseases, for which awareness in host countries is imperative. Health risks in terms of susceptibility to, and dissemination of, infectious diseases are not unidirectional. The response, including the humanitarian effort, whose aim is to guarantee access to basic needs (food, water and sanitation, healthcare), is gripped with numerous challenges. Evaluation of current policy shows insufficiency regarding the provision of basic needs to migrant populations, even in the countries that do the most. Governments around the world need to rise to the occasion and adopt policies that guarantee universal health coverage, for migrants and refugees, as well as host populations, in accordance with the UN Sustainable Development Goals. An expert consultation was carried out in the form of a pre-conference workshop during the 4th International Conference on Prevention and Infection Control (ICPIC) in Geneva, Switzerland, on 20 June 2017, the United Nations World Refugee Day.