Cross-border Malaria Research Articles

Contributing to Elimination of Cross-Border Malaria Through a Standardized Solution for Case Surveillance, Data Sharing, and Data Interpretation: Development of a Cross-Border Monitoring System.

BackgroundCross-border malaria is a significant obstacle to achieving malaria control and elimination worldwide.ObjectiveThis study aimed to build a cross-border surveillance system that can make comparable and qualified data available to all parties involved in malaria control between French Guiana and Brazil.MethodsData reconciliation rules based on expert knowledge were defined and applied to the heterogeneous data provided by the existing malaria surveillance systems of both countries. Visualization dashboards were designed to facilitate progressive data exploration, analysis, and interpretation. Dedicated advanced open source and robust software solutions were chosen to facilitate solution sharing and reuse.ResultsA database gathering the harmonized data on cross-border malaria epidemiology is updated monthly with new individual malaria cases from both countries. Online dashboards permit a progressive and user-friendly visualization of raw data and epidemiological indicators, in the form of time series, maps, and data quality indexes. The monitoring system was shown to be able to identify changes in time series that are related to control actions, as well as differentiated changes according to space and to population subgroups.ConclusionsThis cross-border monitoring tool could help produce new scientific evidence on cross-border malaria dynamics, implementing cross-border cooperation for malaria control and elimination, and can be quickly adapted to other cross-border contexts.

Using parasite genetic and human mobility data to infer local and cross-border malaria connectivity in Southern Africa.

Local and cross-border importation remain major challenges to malaria elimination and are difficult to measure using traditional surveillance data. To address this challenge, we systematically collected parasite genetic data and travel history from thousands of malaria cases across northeastern Namibia and estimated human mobility from mobile phone data. We observed strong fine-scale spatial structure in local parasite populations, providing positive evidence that the majority of cases were due to local transmission. This result was largely consistent with estimates from mobile phone and travel history data. However, genetic data identified more detailed and extensive evidence of parasite connectivity over hundreds of kilometers than the other data, within Namibia and across the Angolan and Zambian borders. Our results provide a framework for incorporating genetic data into malaria surveillance and provide evidence that both strengthening of local interventions and regional coordination are likely necessary to eliminate malaria in this region of Southern Africa.

Burden of Malaria in three Endemic Districts of Bhutan: Road to Malaria Elimination

Introduction: Bhutan is considered as a low endemic country for malaria. In the last decade, Bhutan has successfully reduced the number of malaria cases with the support from Global Fund and WHO. Sarpang, Samtse and Samdrup Jongkhar districts located in the Southern foothills of Bhutan records the most cases. Method: This retrospective study was undertaken with the available census record maintained in health centers of the three endemic districts and VDCP. Results: There were 892 confirmed malaria cases in 2009 and 41 cases in 2017 in three endemic districts. The slide positivity rate (SPR) declined from 2.2% in 2009 to 0.1% in 2017. The distribution of disease was significantly higher (p<0.05) amongst the male population with the increasing trend of Plasmodium vivax infection. The study found predominance of P. vivax in Samtse (93%), and Sarpang (62%) and Plasmodium falciparum in Samdrup Jongkhar (61%). The last four years (2014-2017) data showed that maximum cases detected were imported, followed by indigenous and introduced malaria; with 50%, 44% and 6%, respectively. The mortality and morbidity due to malaria has magnificently declined in the last decade. Conclusion: The large-scale implementation of vector control interventions, such as insecticide-treated bed nets, indoor residual spraying, free health care service and active vector surveillance has achieved a marked reduction in malaria incidence. Cross border malaria is still a huge challenge for elimination of malaria in Bhutan. Thus, imported malaria is an increasing problem due to high receptivity, and vulnerability.

Bayesian spatiotemporal analysis of malaria infection along an international border: Hlaingbwe Township in Myanmar and Tha-Song-Yang District in Thailand

BackgroundOne challenge in moving towards malaria elimination is cross-border malaria infection. The implemented measures to prevent and control malaria re-introduction across the demarcation line between two countries require intensive analyses and interpretation of data from both sides, particularly in border areas, to make correct and timely decisions. Reliable maps of projected malaria distribution can help to direct intervention strategies. In this study, a Bayesian spatiotemporal analytic model was proposed for analysing and generating aggregated malaria risk maps based on the exceedance probability of malaria infection in the township-district adjacent to the border between Myanmar and Thailand. Data of individual malaria cases in Hlaingbwe Township and Tha-Song-Yang District during 2016 were extracted from routine malaria surveillance databases. Bayesian zero-inflated Poisson model was developed to identify spatial and temporal distributions and associations between malaria infections and risk factors. Maps of the descriptive statistics and posterior distribution of predicted malaria infections were also developed.ResultsA similar seasonal pattern of malaria was observed in both Hlaingbwe Township and Tha-Song-Yang District during the rainy season. The analytic model indicated more cases of malaria among males and individuals aged ≥ 15 years. Mapping of aggregated risk revealed consistently high or low probabilities of malaria infection in certain village tracts or villages in interior parts of each country, with higher probability in village tracts/villages adjacent to the border in places where it could easily be crossed; some border locations with high mountains or dense forests appeared to have fewer malaria cases. The probability of becoming a hotspot cluster varied among village tracts/villages over the year, and some had close to no cases all year.ConclusionsThe analytic model developed in this study could be used for assessing the probability of hotspot cluster, which would be beneficial for setting priorities and timely preventive actions in such hotspot cluster areas. This approach might help to accelerate reaching the common goal of malaria elimination in the two countries.

Comparison of PfHRP-2/pLDH RDTs with Light Microscopy in a Low Prevalence Setting in Southeastern Iran, Sistan and Baluchestan: Due to Implementation of Malaria Elimination Program

Background: The gold standard for diagnosing malaria in Iran is using light microscopy; however, this method requires equipment, time and skilled microscopists. In some circumstances, rapid diagnostic test (RDTs) can be a proper substitute. Assessing the diagnostic performance of RDT relative to microscopy, for the diagnosis of malaria in Southeastern Iran, Sistan and Baluchestan, was the purpose of this study. Methods: From March to July 2016, which was a peak transmission season in Iran, 318 patients with suspected malaria were taken for a blood sample at the health center in Saravan, in Sistan and Baluchestan Province. The samples were surveyed instantly by light microscopy and RDT. Comparison analysis included: sensitivity, specificity, positive and negative predictive values, and other diagnostic screening performance measures for detecting malaria infections. Results: Of the 318 malaria cases (6.6%), 21 were identified by a microscopy compared to 22 of 318 (6.9%) by RDT. RDT sensitivity and specificity for the diagnosis of malaria were 95.5% (77.2% - 99.9%, 95% CI) and 100% (98.8% - 100%, 95% CI), respectively, compared to standard microscopy, the sensitivity and specificity for vivax malaria were 100% (79.4-100%, 95% CI) and 99.7% (98.14% - 99.99%, 95% CI), and for falciparum malaria: 80% (28.4% - 99.5%, 95% CI) and 100% (98.8% - 100%, 95% CI). Two tests showed an amazing agreement with a kappa estimation of 0.975. Conclusions: The study proved that the RDT test performs appropriately for the identification of infections with P. falciparum and P. vivax malaria in cross-border malaria. Moreover, the RDT can be a useful instrument for the identification of new clinical cases of malaria in this region.

Imported Plasmodium falciparum and locally transmitted Plasmodium vivax: cross-border malaria transmission scenario in northwestern Thailand

BackgroundCross-border malaria transmission is an important problem for national malaria control programmes. The epidemiology of cross-border malaria is further complicated in areas where Plasmodium falciparum and Plasmodium vivax are both endemic. By combining passive case detection data with entomological data, a transmission scenario on the northwestern Thai–Myanmar border where P. falciparum is likely driven by importation was described, whereas P. vivax is also locally transmitted. This study highlights the differences in the level of control required to eliminate P. falciparum and P. vivax from the same region.MethodsMalaria case data were collected from malaria clinics in Suan Oi village, Tak Province, Thailand between 2011 and 2014. Infections were diagnosed by light microscopy. Demographic data, including migrant status, were correlated with concomitantly collected entomology data from 1330 mosquito trap nights using logistic regression. Malaria infection in the captured mosquitoes was detected by ELISA.ResultsRecent migrants were almost four times more likely to be infected with P. falciparum compared with Thai patients (OR 3.84, p < 0.001) and cases were significantly associated with seasonal migration. However, P. falciparum infection was not associated with the Anopheles mosquito capture rates, suggesting predominantly imported infections. In contrast, recent migrants were equally likely to present with P. vivax as mid-term migrants. Both migrant groups were twice as likely to be infected with P. vivax in comparison to the resident Thai population (OR 1.96, p < 0.001 and OR 1.94, p < 0.001, respectively). Plasmodium vivax cases were strongly correlated with age and local capture rates of two major vector species Anopheles minimus and Anopheles maculatus (OR 1.23, p = 0.020 and OR 1.33, p = 0.046, respectively), suggesting that a high level of local transmission might be causing these infections.ConclusionsOn the Thai–Myanmar border, P. falciparum infections occur mostly in the recent migrant population with a seasonality reflecting that of agricultural activity, rather than that of the local mosquito population. This suggests that P. falciparum was mostly imported. In contrast, P. vivax cases were significantly associated with mosquito capture rates and less with migrant status, indicating local transmission. This highlights the different timelines and requirements for P. falciparum and P. vivax elimination in the same region and underlines the importance of multinational, cross-border malaria control.

Malaria risk in young male travellers but local transmission persists: a case\u2013control study in low transmission Namibia

Background A key component of malaria elimination campaigns is the identification and targeting of high risk populations. To characterize high risk populations in north central Namibia, a prospective health facility-based case–control study was conducted from December 2012–July 2014. Cases (n = 107) were all patients presenting to any of the 46 health clinics located in the study districts with a confirmed Plasmodium infection by multi-species rapid diagnostic test (RDT). Population controls (n = 679) for each district were RDT negative individuals residing within a household that was randomly selected from a census listing using a two-stage sampling procedure. Demographic, travel, socio-economic, behavioural, climate and vegetation data were also collected. Spatial patterns of malaria risk were analysed. Multivariate logistic regression was used to identify risk factors for malaria.ResultsMalaria risk was observed to cluster along the border with Angola, and travel patterns among cases were comparatively restricted to northern Namibia and Angola. Travel to Angola was associated with excessive risk of malaria in males (OR 43.58 95% CI 2.12–896), but there was no corresponding risk associated with travel by females. This is the first study to reveal that gender can modify the effect of travel on risk of malaria. Amongst non-travellers, male gender was also associated with a higher risk of malaria compared with females (OR 1.95 95% CI 1.25–3.04). Other strong risk factors were sleeping away from the household the previous night, lower socioeconomic status, living in an area with moderate vegetation around their house, experiencing moderate rainfall in the month prior to diagnosis and living <15 km from the Angolan border.ConclusionsThese findings highlight the critical need to target malaria interventions to young male travellers, who have a disproportionate risk of malaria in northern Namibia, to coordinate cross-border regional malaria prevention initiatives and to scale up coverage of prevention measures such as indoor residual spraying and long-lasting insecticide nets in high risk areas if malaria elimination is to be realized.

Molecular Epidemiology of P. vivax in Iran: High Diversity and Complex Sub-Structure Using Neutral Markers, but No Evidence of Y976F Mutation at pvmdr1.

BackgroundMalaria remains endemic at low levels in the south-eastern provinces of Iran bordering Afghanistan and Pakistan, with the majority of cases attributable to P. vivax. The national guidelines recommend chloroquine (CQ) as blood-stage treatment for uncomplicated P. vivax, but the large influx of imported cases enhances the risk of introducing CQ resistance (CQR).Methodology and Principal FindingsThe genetic diversity at pvmdr1, a putative modulator of CQR, and across nine putatively neutral short tandem repeat (STR) markers were assessed in P. vivax clinical isolates collected between April 2007 and January 2013 in Hormozgan Province, south-eastern Iran. One hundred blood samples were collected from patients with microscopy-confirmed P. vivax enrolled at one of five district clinics. In total 73 (73%) were autochthonous cases, 23 (23%) imported cases from Afghanistan or Pakistan, and 4 (4%) with unknown origin. 97% (97/100) isolates carried the F1076L mutation, but none carried the Y976F mutation. STR genotyping was successful in 71 (71%) isolates, including 57(57%) autochthonous and 11 (11%) imported cases. Analysis of population structure revealed 2 major sub-populations, K1 and K2, with further sub-structure within K2. The K1 sub-population had markedly lower diversity than K2 (HE = 0.06 vs HE = 0.82) suggesting that the sub-populations were sustained by distinct reservoirs with differing transmission dynamics, possibly reflecting local versus imported/introduced populations. No notable separation was observed between the local and imported cases although the sample size was limited.ConclusionsThe contrasting low versus high diversity in the two sub-populations (K1 and K2) infers that a combination of local transmission and cross-border malaria from higher transmission regions shape the genetic make-up of the P. vivax population in south-eastern Iran. There was no molecular evidence of CQR amongst the local or imported cases, but ongoing clinical surveillance is warranted.

Risk assessment of malaria in land border regions of China in the context of malaria elimination.

BackgroundCross-border malaria transmission poses a challenge for countries to achieve and maintain malaria elimination. Because of a dramatic increase of cross-border population movement between China and 14 neighbouring countries, the malaria epidemic risk in China’s land border regions needs to be understood.MethodsIn this study, individual case-based epidemiological data on malaria in the 136 counties of China with international land borders, from 2011 to 2014, were extracted from the National Infectious Disease Information System. The Plasmodium species, seasonality, spatiotemporal distribution and changing features of imported and indigenous cases were analysed using descriptive spatial and temporal methods.ResultsA total of 1948 malaria cases were reported, with 1406 (72.2%) imported cases and 542 (27.8%) indigenous cases. Plasmodium vivax is the predominant species, with 1536 malaria cases occurrence (78.9%), following by Plasmodium falciparum (361 cases, 18.5%), and the others (51 cases, 2.6%). The magnitude and geographic distribution of malaria in land border counties shrunk sharply during the elimination period. Imported malaria cases were with a peak of 546 cases in 2011, decreasing yearly in the following years. The number of counties with imported cases decreased from 28 counties in 2011 to 26 counties in 2014. Indigenous malaria cases presented a markedly decreasing trend, with 319 indigenous cases in 2011 reducing to only 33 indigenous cases in 2014. The number of counties with indigenous cases reduced from 26 counties in 2011 to 10 counties in 2014. However, several bordering counties of Yunnan province adjacent to Myanmar reported indigenous malaria cases in the four consecutive years from 2011 to 2014.ConclusionsThe scale and extent of malaria occurrence in the international land border counties of China decreased dramatically during the elimination period. However, several high-risk counties, especially along the China–Myanmar border, still face a persistent risk of malaria introduction and transmission. The study emphasizes the importance and urgency of cross-border cooperation between neighbouring countries to jointly face malaria threats to elimination goals.

Linking malaria in Limpopo province, South Africa to climate using self-organizing maps

Introduction-Global malaria cases have drastically dropped in recent years, however there is still high incidence in sub-Saharan African countries. South Africa is mostly malaria-free, but northeastern provinces still have seasonal transmission of malaria. Past studies have reported various relationships between malaria and climatic factors. The aim of this study is to investigate patterns in malaria incidence in Limpopo and explore the association to climate conditions. Methods-Self-organizing maps were used to find patterns in malaria incidence based on case data. Composite analysis showed different climate patterns that associated to high and low incidence events. Classification methods were used to predict future malaria incidence. Results-Strong association of high malaria incidence to climate were found at varying lags. Interestingly significant association was seen with the rainfall of neighboring Mozambique at 2- to 4-months lag, as well as strong easterly winds over Mozambique Channel at 2-month lag, and drier conditions in Limpopo at 0- and 1-month lag. These provided optimal conditions for malaria incidence to reach higher rates during spring and lasting for consecutive seasons. Composite maps of sea surface temperature showed La Nina patterns in the tropical Pacific, which cause higher than normal rainfall over southern Africa. In contrast, seasons with low incidence were associated with considerably drier conditions at 2-month lag, and more westerly winds over southern Africa. Classification methods predicted events of high and low malaria incidence several months in advance. Conclusion-Links of malaria incidence to lagged climate patterns of temperatures in Limpopo, rainfall in Mozambique, zonal winds over the Mozambique Channel, and La Nina events suggest the importance of local climate as well as that of neighboring countries. This implies that there is a need for strengthening cross-border malaria control management to minimize the spread of malaria.

High-Resolution Plasmodium falciparum Malaria Risk Mapping in Mutasa District, Zimbabwe: Implications for Regaining Control.

In Zimbabwe, more than half of malaria cases are concentrated in Manicaland Province, where seasonal malaria epidemics occur despite intensified control strategies. The objectives of this study were to develop a prediction model based on environmental risk factors and obtain seasonal malaria risk maps for Mutasa District, one of the worst affected districts in Manicaland Province. From October 2012 to September 2015, 483 households were surveyed, and 104 individuals residing within 69 households had positive rapid diagnostic test results. Logistic regression was used to model the probability of household positivity as a function of the environmental covariates extracted from high-resolution remote sensing data sources. Model predictions and prediction standard errors were generated for the rainy and dry seasons. The resulting maps predicted elevated risk during the rainy season, particularly in low-lying areas bordering Mozambique. In contrast, the risk of malaria was low across the study area during the dry season with foci of malaria risk scattered along the northern and western peripheries of the study area. These findings underscore the need for strong cross-border malaria control initiatives to complement country-specific interventions.

Cross-border malaria: a major obstacle for malaria elimination.

Movement of malaria across international borders poses a major obstacle to achieving malaria elimination in the 34 countries that have committed to this goal. In border areas, malaria prevalence is often higher than in other areas due to lower access to health services, treatment-seeking behaviour of marginalized populations that typically inhabit border areas, difficulties in deploying prevention programmes to hard-to-reach communities, often in difficult terrain, and constant movement of people across porous national boundaries. Malaria elimination in border areas will be challenging and key to addressing the challenges is strengthening of surveillance activities for rapid identification of any importation or reintroduction of malaria. This could involve taking advantage of technological advances, such as spatial decision support systems, which can be deployed to assist programme managers to carry out preventive and reactive measures, and mobile phone technology, which can be used to capture the movement of people in the border areas and likely sources of malaria importation. Additionally, joint collaboration in the prevention and control of cross-border malaria by neighbouring countries, and reinforcement of early diagnosis and prompt treatment are ways forward in addressing the problem of cross-border malaria.

Malaria 2050: from science to strategy; from evidence to eradication

The malaria community has moved rapidly from acceptance of the possibility of elimination in some countries to an active discussion about eventual human malaria eradication, perhaps by 2050. If this ambitious goal is to be achieved, several things are necessary. First, we must have a clear overall strategy for the achievement of malaria eradication. This involves three equally important elements: • Aggressive control in the heartland to bring malaria burden from high to low. • Shrinking the malaria map by eliminating transmission in countries at the endemic margins. • Research to bring forward new drugs, vaccines, insecticides and other tools and technologies. Second, we must have a clear roadmap leading to eradication in 2050. If all countries have eliminated by 2050, what must the 2040 map look like? What must the 2030 map look like? And so on. We must set ambitious but achievable five-yearly targets. These must be accompanied by research timelines for the discovery of new and better tools and technologies. Third, we must aggressively use today’s tools today and be ready to adopt and rapidly scale-up tomorrow’s tools for tomorrow. Fourth, we must work to strengthen both national programs and regional collaborations. Two significant regional collaborations, APMEN and E8, provide models. Fifth, we must overcome specific technical challenges including artemisinin-resistant P. falciparum, Plasmodium knowlesi, cross-border malaria movement, and the systemically weak management that is found in most National Malaria Control Programs. Sixth, we must ensure adequate finance, not only to reach elimination, but to prevent reintroduction. The possibility of declining budgets in the face of declining malaria, and no budgets in the face of no malaria, is ever present. Sri Lanka in the 1960s will repeat itself if we are not proactive. We vaccinate against measles where there is no measles. We need to invest in malaria control where there is no malaria. Finally, we must continue to transition from a science-led malaria endeavor to a science-supported malaria endeavor. Scientists will always focus on what we do not know and on the lack of evidence to support aggressive action. Leadership needs to come from those who are experienced in bold action based on sufficient evidence, to create a more ambitious trajectory toward eradication. And this leadership needs to be supported by the best scientists and the most vigorous development of new products and tools. Linked to this culture of action, must be an emphasis on operational research and learning while doing. With these and other commitments and efforts, we can collectively embrace the vision of a planet with no human malaria by 2050.

Quantifying cross-border movements and migrations for guiding the strategic planning of malaria control and elimination.

BackgroundIdentifying human and malaria parasite movements is important for control planning across all transmission intensities. Imported infections can reintroduce infections into areas previously free of infection, maintain ‘hotspots’ of transmission and import drug resistant strains, challenging national control programmes at a variety of temporal and spatial scales. Recent analyses based on mobile phone usage data have provided valuable insights into population and likely parasite movements within countries, but these data are restricted to sub-national analyses, leaving important cross-border movements neglected.MethodsNational census data were used to analyse and model cross-border migration and movement, using East Africa as an example. ‘Hotspots’ of origin-specific immigrants from neighbouring countries were identified for Kenya, Tanzania and Uganda. Populations of origin-specific migrants were compared to distance from origin country borders and population size at destination, and regression models were developed to quantify and compare differences in migration patterns. Migration data were then combined with existing spatially-referenced malaria data to compare the relative propensity for cross-border malaria movement in the region.ResultsThe spatial patterns and processes for immigration were different between each origin and destination country pair. Hotspots of immigration, for example, were concentrated close to origin country borders for most immigrants to Tanzania, but for Kenya, a similar pattern was only seen for Tanzanian and Ugandan immigrants. Regression model fits also differed between specific migrant groups, with some migration patterns more dependent on population size at destination and distance travelled than others. With these differences between immigration patterns and processes, and heterogeneous transmission risk in East Africa and the surrounding region, propensities to import malaria infections also likely show substantial variations.ConclusionThis was a first attempt to quantify and model cross-border movements relevant to malaria transmission and control. With national census available worldwide, this approach can be translated to construct a cross-border human and malaria movement evidence base for other malaria endemic countries. The outcomes of this study will feed into wider efforts to quantify and model human and malaria movements in endemic regions to facilitate improved intervention planning, resource allocation and collaborative policy decisions.

Regional Initiatives in Support of Surveillance in East Africa: The East Africa Integrated Disease Surveillance Network (EAIDSNet) Experience

The East African Integrated Disease Surveillance Network (EAIDSNet) was formed in response to a growing frequency of cross-border malaria outbreaks in the 1990s and a growing recognition that fragmented disease interventions, coupled with weak laboratory capacity, were making it difficult to respond in a timely manner to the outbreaks of malaria and other infectious diseases. The East Africa Community (EAC) partner states, with financial support from the Rockefeller Foundation, established EAIDSNet in 2000 to develop and strengthen the communication channels necessary for integrated cross-border disease surveillance and control efforts. The objective of this paper is to review the regional EAIDSNet initiative and highlight achievements and challenges in its implementation. Major accomplishments of EAIDSNet include influencing the establishment of a Department of Health within the EAC Secretariat to support a regional health agenda; successfully completing a regional field simulation exercise in pandemic influenza preparedness; and piloting a web-based portal for linking animal and human health disease surveillance. The strategic direction of EAIDSNet was shaped, in part, by lessons learned following a visit to the more established Mekong Basin Disease Surveillance (MBDS) regional network. Looking to the future, EAIDSNet is collaborating with the East, Central and Southern Africa Health Community (ECSA-HC), EAC partner states, and the World Health Organization to implement the World Bank-funded East Africa Public Health Laboratory Networking Project (EAPHLNP). The network has also begun lobbying East African countries for funding to support EAIDSNet activities.

Malaria control in South Africa 2000–2010: beyond MDG6

BackgroundMalaria is one of the key targets within Goal 6 of the Millennium Development Goals (MDGs), whereby the disease needs to be halted and reversed by the year 2015. Several other international targets have been set, however the MDGs are universally accepted, hence it is the focus of this manuscript.MethodsAn assessment was undertaken to determine the progress South Africa has made against the malaria target of MDG Goal 6. Data were analyzed for the period 2000 until 2010 and verified after municipal boundary changes in some of South Africa’s districts and subsequent to verifying actual residence of malaria positive cases.ResultsSouth Africa has made significant progress in controlling malaria transmission over the past decade; malaria cases declined by 89.41% (63663 in 2000 vs 6741 in 2010) and deaths decreased by 85.4% (453 vs 66) in the year 2000 compared to the year 2010. Coupled with this, malaria cases among children under five years of age have also declined by 93% (6791 in 2000 vs 451 in 2010). This has resulted in South Africa achieving and exceeding the malaria target of the MDGs. A series of interventions have attributed to this decrease, these include: drug policy change from monotherapy to artemisinin combination therapy, insecticide change from pyrethroids back to DDT; cross border collaboration (South Africa with Mozambique and Swaziland through the Lubombo Spatial Development Initiative– LSDI) and financial investment in malaria control. The KwaZulu-Natal Province has seen the largest reduction in malaria cases and deaths (99.1% cases- 41786 vs 380; and 98.5% deaths 340 vs 5), when comparing the year 2000 with 2010. The Limpopo Province recorded the lowest reduction in malaria cases compared to the other malaria endemic provinces (56.1% reduction- 9487 vs 4174; when comparing 2000 to 2010).ConclusionsSouth Africa is well positioned to move beyond the malaria target of the MDGs and progress towards elimination. However, in addition to its existing interventions, the country will need to sustain its financing for malaria control and support programmed reorientation towards elimination and scale up active surveillance coupled with treatment at the community level. Moreover cross-border malaria collaboration needs to be sustained and scaled up to prevent the re-introduction of malaria into the country.

Joint malaria surveys lead towards improved cross-border cooperation between Savannakhet province, Laos and Quang Tri province, Vietnam

BackgroundIn Savannakhet province, Laos and Quang Tri province, Vietnam, malaria is still an important health problem and most cases are found in the mountainous, forested border areas where ethnic minority groups live. The objectives of this study were to obtain a better joint understanding of the malaria situation along the border and, on the basis of that, improve malaria control methods through better cooperation between the two countries.MethodsFourteen villages in Savannakhet and 22 villages in Quang Tri were randomly selected within 5 km from the border where a blood survey for microscopic diagnosis (n = 1256 and n = 1803, respectively), household interviews (n = 400, both sides) and vector surveys were conducted between August and October 2010. Satellite images were used to examine the forest density around the study villages.ResultsMalaria prevalence was significantly higher in Laos (5.2%) than in Vietnam (1.8%) and many other differences were found over the short distance across the border. Bed net coverage was high (> 90%) in both Laos and Vietnam but, while in Laos more than 60% of the nets were long-lasting insecticide-treated, Vietnam used indoor residual spraying in this area and the nets were untreated. Anopheles mosquitoes were more abundant in Laos than in Vietnam, especially many Anopheles dirus were captured in indoor light traps while none were collected in Vietnam. The forest cover was higher around the Lao than the Vietnamese villages. After this study routine exchange of malaria surveillance data was institutionalized and for the first time indoor residual spraying was applied in some Lao villages.ConclusionsThe abundance of indoor-collected An. dirus on the Laos side raises doubts about the effectiveness of a sole reliance on long-lasting insecticide-treated nets in this area. Next to strengthening the early detection, correct diagnosis and prompt, adequate treatment of malaria infections, it is recommended to test focal indoor residual spraying and the promotion of insect repellent use in the early evening as additional vector interventions. Conducting joint malaria surveys by staff of two countries proved to be effective in stimulating better collaboration and improve cross-border malaria control.