A severe diarrhoeal outbreak in a remote Pacific island community, Anuta Island, Solomon Islands, April-June 2019.

CONTEXT: Solomon Islands is a small developing island state located in the south-western Pacific Ocean. A population of approximately 680 000 people live on more than one-third of the 992 islands that make up the country. Approximately 80% of the population reside in rural areas, many in remote, difficult to reach and poorly serviced island settings. ISSUE: In May 2019, the national surveillance system detected a rumour of a severe diarrhoea outbreak in a very remote and isolated community on Anuta Island, located halfway between the Solomon Islands archipelago and Tuvalu. This communication reports on the investigation and response to the outbreak, which affected 50 people (attack rate of 21.5%) and caused four deaths (case fatality rate of 8%). The authors highlight the system challenges faced in mounting the response and provide suggestions that may help overcome them. LESSONS LEARNED: The outbreak highlighted the challenges in detecting and responding to outbreaks in remote and rural areas of the Pacific Islands, and the limitations of rumour surveillance as a relied-upon surveillance strategy. The outbreak emphasises the need to build local capacity to detect, report and respond to outbreaks and the need for policy frameworks that ensure remote communities receive adequate health protection services.

Killing Dynamics of Carbapenems against Pseudomonas aeruginosa Harboring Varied Determinants of Carbapenem Resistance / 대한임상미생물학회지

Background@#Ideal dose of the antimicrobials should be decided by considering their killing dynamics since sufficient elimination of the causative microorganisms is critical for proper antimicrobial treatment. In this study, the bactericidal activities of carbapenems by resistance mechanisms were assessed for carbapenem-resistant Pseudomonas aeruginosa. @*Methods@#Minimal inhibition concentrations (MICs) of carbapenems were determined by broth dilution method and the resistance mechanisms were identified by PCR and DNA sequencing. The expression levels of efflux pumps were determined by reverse transcriptase real-time PCR. Time-kill curves were plotted by time-course numeration of the viable cells grown under imipenem and meropenem at 1× and 4×MICs, respectively. @*Results@#One P. aeruginosa strain was susceptible, whereas three were resistant to carbapenems by defective OprD, efflux pump overproduction, and/or IMP-6 production.The susceptible strain had imipenem and meropenem MICs of 2 and 1 mg/L, respectively.The MICs were elevated by eight-fold by defective OprD, 16- and 32-fold by the pump overproduction, and four- and >64-fold by the combination of two determinants and the IMP-6 carbapenemase. While both the carbapenems showed time-dependent bactericidal activity to the susceptible isolate, either of the carbapenem-resistant determinants, such as decreased membrane permeability, carbapenemase production, or the defective OprD, presented concentration-dependent bacteriostatic activity. @*Conclusion@#Different killing dynamics of the carbapenems were observed depending on the resistance determinants, and the results would guide a proper treatment strategy for the patients using these drugs.