ABSTRACT
This project aimed to identify and prioritize opportunities for sustainable development of groundwater resources with specific focus on the lowland plains and upland plateaus of Laos. It addressed this aim through three key objectives: (1) establish the potential to develop groundwater for irrigation in key hydrogeological settings in Southern Laos;(2) assess the opportunities that solar-powered pumping technologies may provide smallholder farmers seeking to engage in more profitable, market-oriented agriculture;and (3) enhance the capacity of current and emerging groundwater professionals in Laos. Two areas with promising aquifer development potential were selected in Southern Laos: a drought-prone lowland area underlain by sandstone aquifers in Savannakhet province (Outhomphone district);and a wetter, upland basaltic area on the Bolaven Plateau (Pakxong district). For the first objective, a preliminary hydrogeological assessment was undertaken based on the collation and analysis of existing (limited) data supplemented by data from a network of around 40 to 50 monitoring wells in each district and other hydrogeological measurements collected during two field campaigns. For the second objective, the opportunities for solar-powered groundwater pumping to provide an alternative to conventional grid electricity or fuel pumps was explored through policy analysis and the evaluation of a demonstration project as well as actual field operations. The third and final objective involved a cross-cutting effort to enhance capacity of current or emerging groundwater professionals. For Outhoumphone, where the need for dry season access to reliable groundwater sources is high, the sandstone aquifers present are likely sufficiently replenished but inadequately productive to provide a substantial resource for expanding dry season irrigation. Drillers in the area report well instability, saline water and drilling failure as common technical challenges. With adequate field investigations these challenges may be overcome and supplies for commercial agriculture could become feasible. For Pakxong, where the basaltic aquifers are more productive and reliable, field observations show that more entrepreneurial farmers have already started to develop groundwater for high value commercial crops. There is clear scope to expand irrigation development. Drillers report high success rates for wells and this is supported by the aquifer testing undertaken during this research. Even though policies on solar technologies in agriculture are limited, the solar industry appears to be expanding rapidly, with over twenty solar companies based in Laos;most of which are also servicing the agricultural sector. A demonstration site operated by the National Agriculture and Forestry Research Institute in Vientiane Capital provides firsthand experience of solar pumping and data is emerging on its functioning and performance. Rapid assessments of six solar pumping sites on the Vientiane Plain show that better-off farmers and investors with the means to afford the upfront capital cost are accessing water on demand at effectively little or no marginal cost. Although the situation is evolving rapidly, solar water pumping for agriculture still remains an emerging technology in Laos and hence the long term technical performance, economic viability and potential impacts on the groundwater resources remain entirely unanswered at the present time. A one-week hydro-geophysics training course took place in Pakxong in November 2020 that involved 14 attendees from government agencies and the national university. Training was provided in fieldwork and analysis in new techniques to investigate groundwater using geophysical equipment, site wells, drilling and aquifer testing and aquifer conceptualization. In-situ guidance was provided by in-country team members supported by higher level oversight provided remotely by trainers based in Australia due to travel restrictions associated with COVID-19. The project has also enabled 5 Bachelor, Master and Doctorate students to unde
ABSTRACT
27 Table 1Rhythm disturbances identified in follow up of channelopathy patients Diagnosis Gene testing result Monitoring method Symptoms Rhythm disturbance Alteration to treatment 1 OOHCA Query LQTS Gene negative ICD yes syncope NCT/inappropriate shock BBlocker changed to verapamil 2 OOHCA Query BrS Gene negative ICD none NCT Medication change 3 LQTS KCNQ1 ILR yes palpitations & pre-syncope AF anticoagulation 4 Screening LQTS No gene testing ILR yes palpitations, pre-syncope & syncope SVT EPS/ablation 5 LQTS KCNQ1 Holter none 22% VEs, 7 beats NSVT ICD offered 6 LQTS KCNQ1 Holter yes palpitations PAT BBlocker commenced 7 BrS SCN5a VUS Holter yes palpitations Atrial PACs, NCT, conduction disease, NSVT ICD offered and declined *OOHCA: Out of hospital cardiac arrest, LQTS= LQT syndrome, BrS: Brugada syndrome, BBlocker: beta-blocker, NCT: narrow complex tachycardia, AF: atrial fibrillation, SVT: supraventricular tachycardia, NSVT: non-sustained ventricular tachycardia, PAT: paroxysmal atrial tachycardia, PACs: paroxysmal atrial complex, VE: ventricular ectopic, ILR: implantable loop recorder, ICD: Implantable cardiac defibrillator, EPS: EP study.ConclusionIn our selected channelopathy patients, we demonstrated that the yield of routine monitoring arrangement is low at 10% despite 50% of patients reporting concerning cardiac symptoms. A large proportion of our cohort continue to await rhythm assessment due to delays in scheduling from the Covid-19 pandemic but 93% have had no change in management to date. As of March 2021 mortality was only 1% with just a single patient dying of a suspected dysrhythmia. There is a lack of international guideline on timing of follow up investigation in routine management of channelopathies, but our cohort suggests that routine Holter monitoring in asymptomatic LQTS and BrS does not significantly alter sudden cardiac de th (SCD) risk management. We educate our ICC channelopathy patients’ to report their symptoms to facilitate prompt rhythm assessment, and given pressures on current health systems, perhaps focusing on these symptomatic patients would be an appropriate use of resources.
ABSTRACT
BACKGROUND: Following implementation of strong containment measures, several countries and regions have low detectable community transmission of COVID-19. We developed an efficient, rapid, and scalable surveillance strategy to detect remaining COVID-19 community cases through exhaustive identification of every active transmission chain. We identified measures to enable early detection and effective management of any reintroduction of transmission once containment measures are lifted to ensure strong containment measures do not require reinstatement. METHODS: We compared efficiency and sensitivity to detect community transmission chains through testing of the following: hospital cases; fever, cough and/or ARI testing at community/primary care; and asymptomatic testing; using surveillance evaluation methods and mathematical modelling, varying testing capacities, reproductive number (R) and weekly cumulative incidence of COVID-19 and non-COVID-19 respiratory symptoms using data from Australia. We assessed system requirements to identify all transmission chains and follow up all cases and primary contacts within each chain, per million population. RESULTS: Assuming 20% of cases are asymptomatic and 30% of symptomatic COVID-19 cases present for testing, with R = 2.2, a median of 14 unrecognised community cases (8 infectious) occur when a transmission chain is identified through hospital surveillance versus 7 unrecognised cases (4 infectious) through community-based surveillance. The 7 unrecognised community upstream cases are estimated to generate a further 55-77 primary contacts requiring follow-up. The unrecognised community cases rise to 10 if 50% of cases are asymptomatic. Screening asymptomatic community members cannot exhaustively identify all cases under any of the scenarios assessed. The most important determinant of testing requirements for symptomatic screening is levels of non-COVID-19 respiratory illness. If 4% of the community have respiratory symptoms, and 1% of those with symptoms have COVID-19, exhaustive symptomatic screening requires approximately 11,600 tests/million population using 1/4 pooling, with 98% of cases detected (2% missed), given 99.9% sensitivity. Even with a drop in sensitivity to 70%, pooling was more effective at detecting cases than individual testing under all scenarios examined. CONCLUSIONS: Screening all acute respiratory disease in the community, in combination with exhaustive and meticulous case and contact identification and management, enables appropriate early detection and elimination of COVID-19 community transmission. An important component is identification, testing, and management of all contacts, including upstream contacts (i.e. potential sources of infection for identified cases, and their related transmission chains). Pooling allows increased case detection when testing capacity is limited, even given reduced test sensitivity. Critical to the effectiveness of all aspects of surveillance is appropriate community engagement, messaging to optimise testing uptake and compliance with other measures.