SummaryPresent elimination strategies are based on recommendations derived during the Global Malaria Eradication Program of the 1960s. However, many countries considering elimination nowadays have high intrinsic transmission potential and, without the support of a regional campaign, have to deal with the constant threat of imported cases of the disease, emphasising the need to revisit the strategies on which contemporary elimination programmes are based. To eliminate malaria, programmes need to concentrate on identification and elimination of foci of infections through both passive and active methods of case detection. This approach needs appropriate treatment of both clinical cases and asymptomatic infections, combined with targeted vector control. Draining of infectious pools entirely will not be sufficient since they could be replenished by imported malaria. Elimination will thus additionally need identification and treatment of incoming infections before they lead to transmission, or, more realistically, embarking on regional initiatives to dry up importation at its source.

SummaryIn the past 150 years, roughly half of the countries in the world eliminated malaria. Nowadays, there are 99 endemic countries—67 are controlling malaria and 32 are pursuing an elimination strategy. This four-part Series presents evidence about the technical, operational, and financial dimensions of malaria elimination. The first paper in this Series reviews definitions of elimination and the state that precedes it: controlled low-endemic malaria. Feasibility assessments are described as a crucial step for a country transitioning from controlled low-endemic malaria to elimination. Characteristics of the 32 malaria-eliminating countries are presented, and contrasted with countries that pursued elimination in the past. Challenges and risks of elimination are presented, including Plasmodium vivax, resistance in the parasite and mosquito populations, and potential resurgence if investment and vigilance decrease. The benefits of elimination are outlined, specifically elimination as a regional and global public good. Priorities for the next decade are described.

Abstract. Genetic diversity and population structure of Plasmodium vivax parasites can predict the origin and spread of novel variants within a population enabling population specific malaria control measures. We analyzed the genetic diversity and population structure of 425 P. vivax isolates from Sri Lanka, Myanmar, and Ethiopia using 12 trinucleotide and tetranucleotide microsatellite markers. All three parasite populations were highly polymorphic with 3-44 alleles per locus. Approximately 65% were multiple-clone infections. Mean genetic diversity ( H E ) was 0.7517 in Ethiopia, 0.8450 in Myanmar, and 0.8610 in Sri Lanka. Significant linkage disequilibrium was maintained. Population structure showed two clusters (Asian and African) according to geography and ancestry. Strong clustering of outbreak isolates from Sri Lanka and Ethiopia was observed. Predictive power of ancestry using two-thirds of the isolates as a model identified 78.2% of isolates accurately as being African or Asian. Microsatellite analysis is a useful tool for mapping short-term outbreaks of malaria and for predicting ancestry.

BackgroundSri Lanka has a long history of malaria control, and over the past decade has had dramatic declines in cases amid a national conflict. A case study of Sri Lanka's malaria programme was conducted to characterize the programme and explain recent progress.MethodsThe case study employed qualitative and quantitative methods. Data were collected from published and grey literature, district-level and national records, and thirty-three key informant interviews. Expenditures in two districts for two years – 2004 and 2009 – were compiled.FindingsMalaria incidence in Sri Lanka has declined by 99.9% since 1999. During this time, there were increases in the proportion of malaria infections due to Plasmodium vivax, and the proportion of infections occurring in adult males. Indoor residual spraying and distribution of long-lasting insecticide-treated nets have likely contributed to the low transmission. Entomological surveillance was maintained. A strong passive case detection system captures infections and active case detection was introduced. When comparing conflict and non-conflict districts, vector control and surveillance measures were maintained in conflict areas, often with higher coverage reported in conflict districts. One of two districts in the study reported a 48% decline in malaria programme expenditure per person at risk from 2004 to 2009. The other district had stable malaria spending.Conclusions/SignificanceMalaria is now at low levels in Sri Lanka – 124 indigenous cases were found in 2011. The majority of infections occur in adult males and are due to P. vivax. Evidence-driven policy and an ability to adapt to new circumstances contributed to this decline. Malaria interventions were maintained in the conflict districts despite an ongoing war. Sri Lanka has set a goal of eliminating malaria by the end of 2014. Early identification and treatment of infections, especially imported ones, together with effective surveillance and response, will be critical to achieving this goal.

BackgroundDengue viruses and their mosquito vectors are sensitive to their environment. Temperature, rainfall and humidity have well-defined roles in the transmission cycle. Therefore changes in these conditions may contribute to increasing incidence. The aim of this study was to examine the relationship between weather factors and dengue incidence in three provinces in Cambodia, in order to strengthen the evidence basis of dengue control strategies in this high-burden country.MethodsWe developed negative binomial models using monthly average maximum, minimum, mean temperatures and monthly cumulative rainfall over the period from January 1998 to December 2012. We adopted piecewise linear functions to estimate the incidence rate ratio (IRR) between dengue incidence and weather factors for simplicity in interpreting the coefficients. We estimated the values of parameters below cut-points defined in terms of the results of sensitivity tests over a 0-3 month lagged period.ResultsMean temperature was significantly associated with dengue incidence in all three provinces, but incidence did not correlate well with maximum temperature in Banteay Meanchey, nor with minimum temperature in Kampong Thom at a lag of three months in the negative binomial model. The monthly cumulative rainfall influence on the dengue incidence was significant in all three provinces, but not consistently over a 0-3 month lagged period. Rainfall significantly affected the dengue incidence at a lag of 0 to 3 months in Siem Reap, but it did not have an impact at a lag of 2 to 3 months in Banteay Meanchey, nor at a lag of 2 months in Kampong Thom.ConclusionsThe association between dengue incidence and weather factors also apparently varies by locality, suggesting that a prospective dengue early warning system would likely be best implemented at a local or regional scale, rather than nation-wide in Cambodia. Such spatial down-scaling would also enable dengue control measures to be better targeted, timed and implemented.Electronic supplementary materialThe online version of this article (doi:10.1186/s12889-016-2923-2) contains supplementary material, which is available to authorized users.

The delivery of safe and effective radical cure for Plasmodium vivax is one of the greatest challenges for achieving malaria elimination from the Asia–Pacific by 2030. During the annual meeting of the Asia Pacific Malaria Elimination Network Vivax Working Group in October 2016, a round table discussion was held to discuss the programmatic issues hindering the widespread use of primaquine (PQ) radical cure. Participants included 73 representatives from 16 partner countries and 33 institutional partners and other research institutes. In this meeting report, the key discussion points are presented and grouped into five themes: (i) current barriers for glucose-6-phosphate deficiency (G6PD) testing prior to PQ radical cure, (ii) necessary properties of G6PD tests for wide scale deployment, (iii) the promotion of G6PD testing, (iv) improving adherence to PQ regimens and (v) the challenges for future tafenoquine (TQ) roll out. Robust point of care (PoC) G6PD tests are needed, which are suitable and cost-effective for clinical settings with limited infrastructure. An affordable and competitive test price is needed, accompanied by sustainable funding for the product with appropriate training of healthcare staff, and robust quality control and assurance processes. In the absence of quantitative PoC G6PD tests, G6PD status can be gauged with qualitative diagnostics, however none of the available tests is currently sensitive enough to guide TQ treatment. TQ introduction will require overcoming additional challenges including the management of severely and intermediately G6PD deficient individuals. Robust strategies are needed to ensure that effective treatment practices can be deployed widely, and these should ensure that the caveats are outweighed by  the benefits of radical cure for both the patients and the community. Widespread access to quality controlled G6PD testing will be critical.

SummaryBACKGROUND For the past 18 years, northern Sri Lanka has been affected by armed ethnic conflict. This has had a heavy impact on displacement of civilians, health delivery services, number of health professionals in the area and infrastructure. The north of Sri Lanka has a severe malaria burden, with less than 5% of the national population suffering 34% of reported cases. Health care providers investigated treatment-seeking behaviour and levels of treatment failure believed to be the result of lack of adherence to treatment. METHODSMETHODS Pre-and post-treatment interviews with patients seeking treatment in the outpatient department (OPD) and focus groups.RESULTS RESULTS A total of 271 persons completed interviews: 54.4% sought treatment within 2 days of the onset of symptoms, and 91.9% self-treated with drugs with prior to seeking treatment, mainly with paracetamol. Self-treatment was associated with delaying treatment (RR 3.55, CI 1.23-10.24, P ¼ 0.002). In post-treatment interviews, self-reported default was 26.1%. The main reasons for not taking the entire regimen were side-effects (57.6%) and disappearance of symptoms (16.7%). Focus groups indicated some lack of confidence in chloroquine treatment and prophylaxis, and scant enthusiasm for prevention methods.CONCLUSIONS CONCLUSIONS A number of factors contribute to a lack of access and a lower quality of care for malaria: lack of medical staff and facilities because of the fighting; lack of confidence in treatment, and perception of malaria as a routine illness. Prevention efforts need to take into account certain beliefs and practices to be successful.keywords malaria, conflict, treatment-seeking behaviour, treatment access, prevention correspondence Brigg Reilley,

Abstractobjective To discuss epidemiological aspects of imported malaria and the potential impact of imported malaria cases reported in Sri Lanka 2008-2011 in terms of a possible resurgence of the disease.methods The national malaria database was used to assess details regarding country where the infection was possibly acquired, species of Plasmodium, number of days lapsed between disembarkation in Sri Lanka and diagnosis, compliance with national treatment guidelines including percentage of patients followed up as per the national guidelines.results After the strengthening of malaria surveillance, during the 4-year period, 152 imported malaria cases were recorded: an increase of 176% in the number of cases. Most of the imported malaria infections were acquired by Sri Lankan Nationals mainly from South Asia, especially India. Plasmodium vivax accounted for 64% of the infections. Approximately 50% of the cases were diagnosed in the Western Province. The average period from disembarkation in Sri Lanka to malaria diagnosis was 3.6 days. Patients were managed and treated according to the national guidelines. 82% of the patients were followed up for 28 days to ensure parasite clearance.