Entomological survey in two communes with residual malaria transmission in Gia Lai Province in the central highlands of Vietnam

Abstract Background In 2018, the National Malaria Control Programme in Vietnam switched from prioritizing malaria control to elimination. However, with the ongoing elimination programme, there are still areas where residual malaria transmission persists, including the central highlands. This entomological survey was conducted to evaluate Anopheles diversity and host-seeking activity of Anopheles vectors in two communes with very low malaria transmission in Gia Lai Province. Methods Anopheles species were collected in Ia DReh commune and Ia KDam commune, Gia Lai Province in the central highlands of Vietnam. Collections were conducted using human-baited double net trap, light trap and manual aspiration collections around cattle sheds, in the dry and rainy season. Mosquito specimens were identified morphologically, and members of species complexes were distinguished molecularly. Mosquito night-feeding patterns were investigated during the dry and rainy seasons. Results Overall, 18,835 specimens including 19 taxa were collected in Ia KDam and Ia DReh communes. These included the primary malaria vectors, Anopheles dirus and Anopheles minimus, and other secondary vector species. Anopheles dirus was observed to be an anthropophilic species, whereas An. minimus and a number of secondary vectors were observed to be zoophilic. Anopheles vagus was the dominant species, followed by Anopheles sinensis and Anopheles peditaeniatus. The majority of specimens were collected in the rainy season due to the relatively large number of An. vagus, while An. peditaeniatus, An. dirus, Anopheles kochi, Anopheles monstrosus and Anopheles tessellatus were collected in greater numbers during the dry season. The peak of host-seeking activity for An. dirus, An. sinensis, and An. vagus was between 18.00 and 19.00 h. Conclusion This study provided information on the diversity, seasonal prevalence and behaviour of Anopheles at the study sites. Identifying the diverse mosquito fauna in the central highlands of Vietnam allows species-specific control measures to be implemented by the National Programme to reduce malaria in areas of very low malaria transmission. The peak Anopheles host-seeking activity observed in this study was between 18.00 and 23.00 h, which highlights the need to better characterize Anopheles behaviour in this region of Vietnam to inform on vector control strategies.

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Long-term Transmission Patterns and Public Health Policies Leading to Malaria Elimination in Panamá

10.21203/rs.2.24524/v1 ◽

2020 ◽

Author(s):

Lisbeth Hurtado ◽

Alberto Cumbreras ◽

Chystrie Rigg ◽

Milixa Perea ◽

Ana María Santamaría ◽

...

Keyword(s):

Malaria Transmission ◽

Retrospective Analysis ◽

Malaria Control ◽

Time Series Data ◽

Southern Oscillation ◽

National Malaria Control Programme ◽

Control Programme ◽

Series Data ◽

Malaria Control Programme

Abstract Background: The present study provides a countrywide perspective of the malaria situation in Panama over a long-term framework, with the purpose of identifying historical malaria resurgence events and their potential causes.Methods: A descriptive-ecological study was conducted by analyzing demographic and epidemiological annual malaria time series data in Panamá (1884 – 2019) using several data sources. Malaria intensity indicators were calculated during the study period. We also analyze the effects of El Niño Southern Oscillation on malaria transmission using a retrospective analysis of malaria cases between 1957 and 2019.Results: Several factors were identified responsible for malaria resurgence in Panama, mostly related with Malaria Control Programme weakening. During the past 20 years (2000 – 2019) malaria has progressively increased its prevalence within indigenous settlements, with a predominance of male cases and a high proportion (15% of total cases) in children less than 5 years old. During this period a significant and increasing proportion of the P. falciparum total cases were imported. Our retrospective analysis (1957 - 2019) evidenced that ENSO has a significant impact on malaria transmission dynamics in Panama.Conclusions: Data analysis confirmed that although authorities have been successful in focalizing malaria transmission in the country, there are still neglected issues to be solved and important intercultural barriers that need to be addressed in order to achieve elimination of the disease by 2022. This information will be useful for targeting strategies by the National Malaria Control Programme.

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Vector composition, abundance, biting patterns and malaria transmission intensity in Madang, Papua New Guinea: assessment after 7 years of an LLIN-based malaria control programme

Malaria Journal ◽

10.1186/s12936-021-04030-4 ◽

2022 ◽

Vol 21 (1) ◽

Author(s):

John B. Keven ◽

Michelle Katusele ◽

Rebecca Vinit ◽

Daniela Rodríguez-Rodríguez ◽

Manuel W. Hetzel ◽

...

Keyword(s):

Malaria Transmission ◽

Papua New Guinea ◽

Malaria Control ◽

New Guinea ◽

Control Programme ◽

Transmission Intensity ◽

Bed Nets ◽

Malaria Control Programme ◽

Malaria Transmission Intensity ◽

Vector Abundance

Abstract Background A malaria control programme based on distribution of long-lasting insecticidal bed nets (LLINs) and artemisinin combination therapy began in Papua New Guinea in 2009. After implementation of the programme, substantial reductions in vector abundance and malaria transmission intensity occurred. The research reported here investigated whether these reductions remained after seven years of sustained effort. Methods All-night (18:00 to 06:00) mosquito collections were conducted using human landing catches and barrier screen methods in four villages of Madang Province between September 2016 and March 2017. Anopheles species identification and sporozoite infection with Plasmodium vivax and Plasmodium falciparum were determined with molecular methods. Vector composition was expressed as the relative proportion of different species in villages, and vector abundance was quantified as the number of mosquitoes per barrier screen-night and per person-night. Transmission intensity was quantified as the number of sporozoite-infective vector bites per person-night. Results Five Anopheles species were present, but vector composition varied greatly among villages. Anopheles koliensis, a strongly anthropophilic species was the most prevalent in Bulal, Matukar and Wasab villages, constituting 63.7–73.8% of all Anopheles, but in Megiar Anopheles farauti was the most prevalent species (97.6%). Vector abundance varied among villages (ranging from 2.8 to 72.3 Anopheles per screen-night and 2.2–31.1 Anopheles per person-night), and spatially within villages. Malaria transmission intensity varied among the villages, with values ranging from 0.03 to 0.5 infective Anopheles bites per person-night. Most (54.1–75.1%) of the Anopheles bites occurred outdoors, with a substantial proportion (25.5–50.8%) occurring before 22:00. Conclusion The estimates of vector abundance and transmission intensity in the current study were comparable to or higher than estimates in the same villages in 2010–2012, indicating impeded programme effectiveness. Outdoor and early biting behaviours of vectors are some of the likely explanatory factors. Heterogeneity in vector composition, abundance and distribution among and within villages challenge malaria control programmes and must be considered when planning them.

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Passive Outdoor Host Seeking Device (POHD): Designing and Evaluation against Outdoor Biting Malaria Vectors

The Scientific World JOURNAL ◽

10.1155/2020/4801068 ◽

2020 ◽

Vol 2020 ◽

pp. 1-15

Author(s):

Stella T. Kessy ◽

Ladslaus L. Mnyone ◽

Bruno A. Nyundo ◽

Issa N. Lyimo

Keyword(s):

Carbon Dioxide ◽

Malaria Transmission ◽

Indoor Residual Spraying ◽

Malaria Vectors ◽

Natural Environments ◽

Release Formulation ◽

Experimental Hut ◽

Host Seeking ◽

Outdoor Biting ◽

Residual Malaria Transmission

Odor-baited devices are increasingly needed to compliment long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) for control of residual malaria transmission. However, the odor-baited devices developed so far are bulky, dependent on the source of electricity and carbon dioxide (CO2), and they are logistically unsuitable for scaling up in surveillance and control of malaria vectors. We designed a passive and portable outdoor host seeking device (POHD) and preliminarily evaluated suitable components against Anopheles arabiensis that maintains residual malaria transmission. Experiments were conducted using semifield reared An. arabiensis within the semifield system at Ifakara Health Institute (IHI) in southeastern Tanzania. These mosquitoes were exposed to Suna traps® baited with BG lures or source of light and augmented with carbon dioxide (CO2) in view of identifying best attractants necessary to improve attractiveness of designed POHD. Two Suna traps® were hanged at the corner but outside the experimental hut in a diagonal line and rotated between four corners to control for the effect of position and wind direction on mosquito catches. Furthermore, mosquitoes were also exposed to either a bendiocarb-treated or bendiocarb-untreated POHD baited with Mbita blend, Ifakara blend, and worn socks and augmented with warmth (i.e., 1.5 liter bottle of warm water) inside an experimental hut or a screened rectangular box. This study demonstrated that mosquitoes were more strongly attracted to Suna trap® baited with BG lures and CO2 relative to those traps baited with a source of light and CO2. The POHD baited with synthetic blends attracted and killed greater proportion of An. arabiensis compared with POHD baited with worn socks. Efficacy of the POHD was unaffected by source of warmth, and it was reduced by about 50% when the device was tested inside a screened rectangular box relative to closed experimental hut. Overall, this study demonstrates that the POHD baited with synthetic blends (Mbita and Ifakara blends) and bendiocarb can effectively attract and kill outdoor biting malaria vector species. Such POHD baited with synthetic blends may require the source of CO2 to enhance attractiveness to mosquitoes. Further trials are, therefore, ongoing to evaluate attractiveness of improved design of POHD baited with slow-release formulation of synthetic blends and sustainable source of CO2 to malaria vectors under semifield and natural environments.

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Long-term transmission patterns and public health policies leading to malaria elimination in Panamá

10.21203/rs.2.24524/v4 ◽

2020 ◽

Author(s):

Lisbeth Hurtado ◽

Alberto Cumbrera ◽

Chystrie Rigg ◽

Milixa Perea ◽

Ana María Santamaría ◽

...

Keyword(s):

Malaria Transmission ◽

Retrospective Analysis ◽

Malaria Control ◽

Time Series Data ◽

Southern Oscillation ◽

National Malaria Control Programme ◽

Control Programme ◽

Series Data ◽

Malaria Control Programme

Abstract Background: The present study provides a countrywide perspective of the malaria situation in Panama over a long-term framework, with the purpose of identifying historical malaria resurgence events and their potential causes. Methods: A descriptive-ecological study was conducted by analyzing demographic and epidemiological annual malaria time series data in Panamá (1884 – 2019) using several data sources. Malaria intensity indicators were calculated during the study period. We also analyze the effects of El Niño Southern Oscillation on malaria transmission using a retrospective analysis of malaria cases between 1957 and 2019. Results: Several factors were identified responsible for malaria resurgence in Panama, mostly related with Malaria Control Programme weakening. During the past 20 years (2000 – 2019) malaria has progressively increased its prevalence within indigenous settlements, with a predominance of male cases and a high proportion (15% of total cases) in children less than 5 years old. During this period a significant and increasing proportion of the P. falciparum total cases were imported. Our retrospective analysis (1957 - 2019) evidenced that ENSO has a significant impact on malaria transmission dynamics in Panama. Conclusions: Data analysis confirmed that although authorities have been successful in focalizing malaria transmission in the country, there are still neglected issues to be solved and important intercultural barriers that need to be addressed in order to achieve elimination of the disease by 2022. This information will be useful for targeting strategies by the National Malaria Control Programme.

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Long-Term Transmission Patterns and Public Health Policies Leading to Malaria Elimination in Panamá

10.21203/rs.2.24524/v2 ◽

2020 ◽

Author(s):

Lisbeth Hurtado ◽

Alberto Cumbrera ◽

Chystrie Rigg ◽

Milixa Perea ◽

Ana María Santamaría ◽

...

Keyword(s):

Malaria Transmission ◽

Retrospective Analysis ◽

Malaria Control ◽

Time Series Data ◽

Southern Oscillation ◽

National Malaria Control Programme ◽

Control Programme ◽

Series Data ◽

Malaria Control Programme

Abstract Background: The present study provides a countrywide perspective of the malaria situation in Panama over a long-term framework, with the purpose of identifying historical malaria resurgence events and their potential causes. Methods: A descriptive-ecological study was conducted by analyzing demographic and epidemiological annual malaria time series data in Panamá (1884 – 2019) using several data sources. Malaria intensity indicators were calculated during the study period. We also analyze the effects of El Niño Southern Oscillation on malaria transmission using a retrospective analysis of malaria cases between 1957 and 2019. Results: Several factors were identified responsible for malaria resurgence in Panama, mostly related with Malaria Control Programme weakening. During the past 20 years (2000 – 2019) malaria has progressively increased its prevalence within indigenous settlements, with a predominance of male cases and a high proportion (15% of total cases) in children less than 5 years old. During this period a significant and increasing proportion of the P. falciparum total cases were imported. Our retrospective analysis (1957 - 2019) evidenced that ENSO has a significant impact on malaria transmission dynamics in Panama. Conclusions: Data analysis confirmed that although authorities have been successful in focalizing malaria transmission in the country, there are still neglected issues to be solved and important intercultural barriers that need to be addressed in order to achieve elimination of the disease by 2022. This information will be useful for targeting strategies by the National Malaria Control Programme.

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High level of resistance in the mosquito Anopheles arabiensis to pyrethroid insecticides from low malaria transmission zone of Moroto district, Karamoja region, Uganda: Implication for malaria vector control

10.21203/rs.3.rs-16734/v1 ◽

2020 ◽

Author(s):

Richard Echodu ◽

Juliet Anena ◽

Tereza Iwiru ◽

Paul Mireji ◽

Geoffrey Maxwell Malinga ◽

...

Keyword(s):

Malaria Transmission ◽

Malaria Vector ◽

Malaria Control ◽

Anopheles Arabiensis ◽

Natural Habitats ◽

Transmission Zone ◽

Pirimiphos Methyl ◽

The Impact ◽

Karamoja Region ◽

Low Malaria Transmission

Abstract Background Karamoja region of Uganda previously classified as low malaria transmission zone is currently experiencing significant upsurge of malaria incidences. Long lasting insecticidal nets (LLINs) impregnated with pyrethroids constitute a major tool for malaria control in this region. Efficacy of this tool can be hampered by resistance to the pyrethroids in the Anopheles mosquito vectors. Resistance status of these mosquitoes in this region is poorly understood, effectively hampering better understanding of the impact of LLINs in the malaria control initiative. Here, we assessed susceptibility of the Anopheles arabiensis from the region to deltamethrin, permethrin (pyrethroids) and pirirmiphos-methyl (organophosphate) insecticides. Method We collected anopheline mosquito larvae from their natural habitats and reared them to adult emergence in situ field insectary in Karamoja region. We then identified them morphological to species level and exposed 513 emerge adult female An gambiae s.l., mosquitoes to diagnostic dosages of deltamethrin (0.05%), permethrin (0.75%) and pirimiphos-methyl (0.25%) pyrethroids exposure using the standard WHO insecticide susceptibility test assay. Synergic assays using piperonyl butoxide (PBO) were done to check for the involvement of detoxification enzymes in pyrethroid resistant populations. We then screened for knockdown resistance (KDR) and mosquito species diversity using Polymerase Chain Reaction (PCR). Results Majority (96%) of the mosquitoes we sampled were identified as An. arabiensis and 4% as An. gambiae sensu stricto . We observed cross-resistance to both deltamethrin (11.9%) and permethrin (47%) but susceptibility (100% mortality) to pirimiphos-methyl in An. arabiensis . The pre-exposure to PBO ameliorated the resistance to both pyrethroids. We detected homozygous KDR -eastern variant in 1.8 and 50% of the An. arabiensis and An. gambiae s.s. respectively. Conclusion Anopheles arabiensis and An. gambiae s.s. are the malaria vector in Karamoja region with An. arabiensis predominating. Both species are susceptible to pirimiphos-methyl but resistant to both deltamethrin and permethrin, through a metabolic process (phenotype). Mosquotoes with genetic (kdr) mutations for resistance were minimal and hence have minimal contribution to the pyrethroid resistance profile. An. arabiensis can thus be controled in Karamoja region using deltamethrin and/or permethrin impregnated mosquito nets integrated with PBO and/or through indoor residual spraying of sprayable human dwellings with pirimiphos-methyl.

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High level of resistance in Anopheles arabiensis mosquito to pyrethroid insecticides from low malaria transmission zone of Moroto district, Karamoja region, Uganda: Implication for malaria vector control

10.21203/rs.3.rs-16734/v2 ◽

2020 ◽

Author(s):

Richard Echodu ◽

Juliet Anena ◽

Tereza Iwiru ◽

Paul Mireji ◽

Geoffrey Maxwell Malinga ◽

...

Keyword(s):

Malaria Transmission ◽

Malaria Vector ◽

Malaria Control ◽

Anopheles Arabiensis ◽

Natural Habitats ◽

Transmission Zone ◽

Pirimiphos Methyl ◽

The Impact ◽

Karamoja Region ◽

Low Malaria Transmission

Abstract Background: Karamoja region of Uganda previously classified as low malaria transmission zone is currently experiencing significant upsurge of malaria incidences. Long lasting insecticidal nets (LLINs) impregnated with pyrethroids constitute a major tool for malaria control in this region. Efficacy of this tool can be hampered by resistance to the pyrethroids in the Anopheles mosquito vectors. Resistance status of these mosquitoes in this region is poorly understood, effectively hampering better understanding of the impact of LLINs in the malaria control initiative. Here, we assessed susceptibility of the Anopheles arabiensis from the region to deltamethrin, permethrin (pyrethroids) and pirirmiphos-methyl (organophosphate) insecticides.Method: We collected anopheline mosquito larvae from their natural habitats and reared them to adult emergence in situ field insectary in Karamoja region. We then identified them morphological to species level and exposed 513 emerge adult female An gambiae s.l., mosquitoes to diagnostic dosages of deltamethrin (0.05%), permethrin (0.75%) and pirimiphos-methyl (0.25%) pyrethroids exposure using the standard WHO insecticide susceptibility test assay. Synergic assays using piperonyl butoxide (PBO) were done to check for the involvement of detoxification enzymes in pyrethroid resistant populations. We then screened for knockdown resistance (KDR) and mosquito species diversity using Polymerase Chain Reaction (PCR).Results: Majority (96%) of the mosquitoes we sampled were identified as An. arabiensis and 4% as An. gambiae sensu stricto. We observed cross-resistance to both deltamethrin (11.9%) and permethrin (47%) but susceptibility (100% mortality) to pirimiphos-methyl in An. arabiensis. The pre-exposure to PBO ameliorated the resistance to both pyrethroids. We detected homozygous KDR -eastern variant in 1.8 and 50% of the An. arabiensis and An. gambiae s.s. respectively.Conclusion: Anopheles arabiensis and An. gambiae s.s. are the malaria vector in Karamoja region with An. arabiensis predominating. Both species are susceptible to pirimiphos-methyl but resistant to both deltamethrin and permethrin, through a metabolic process (phenotype). Mosquotoes with genetic (kdr) mutations for resistance were minimal and hence have minimal contribution to the pyrethroid resistance profile. An. arabiensis can thus be controled in Karamoja region using deltamethrin and/or permethrin impregnated mosquito nets integrated with PBO and/or through indoor residual spraying of sprayable human dwellings with pirimiphos-methyl.

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Long-Term Transmission Patterns And Public Health Policies Leading To Malaria Elimination In Panamá

10.21203/rs.2.24524/v3 ◽

2020 ◽

Author(s):

Lisbeth Hurtado ◽

Alberto Cumbrera ◽

Chystrie Rigg ◽

Milixa Perea ◽

Ana María Santamaría ◽

...

Keyword(s):

Malaria Transmission ◽

Retrospective Analysis ◽

Malaria Control ◽

Time Series Data ◽

Southern Oscillation ◽

National Malaria Control Programme ◽

Control Programme ◽

Series Data ◽

Malaria Control Programme

Abstract Background: The present study provides a countrywide perspective of the malaria situation in Panama over a long-term framework, with the purpose of identifying historical malaria resurgence events and their potential causes. Methods: A descriptive-ecological study was conducted by analyzing demographic and epidemiological annual malaria time series data in Panamá (1884 – 2019) using several data sources. Malaria intensity indicators were calculated during the study period. We also analyze the effects of El Niño Southern Oscillation on malaria transmission using a retrospective analysis of malaria cases between 1957 and 2019. Results: Several factors were identified responsible for malaria resurgence in Panama, mostly related with Malaria Control Programme weakening. During the past 20 years (2000 – 2019) malaria has progressively increased its prevalence within indigenous settlements, with a predominance of male cases and a high proportion (15% of total cases) in children less than 5 years old. During this period a significant and increasing proportion of the P. falciparum total cases were imported. Our retrospective analysis (1957 - 2019) evidenced that ENSO has a significant impact on malaria transmission dynamics in Panama. Conclusions: Data analysis confirmed that although authorities have been successful in focalizing malaria transmission in the country, there are still neglected issues to be solved and important intercultural barriers that need to be addressed in order to achieve elimination of the disease by 2022. This information will be useful for targeting strategies by the National Malaria Control Programme.

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Lack of community awareness on malaria and its vectors can impede malaria control: A case study in Great Nicobar Islands

INTERNATIONAL JOURNAL OF EXPERIMENTAL RESEARCH AND REVIEW ◽

10.52756/ijerr.2017.v12.001 ◽

2017 ◽

Vol 12 ◽

pp. 1-13

Author(s):

Vidhya Pachalil Thiruvoth ◽

◽

Sunish Ittoop Pulikotil ◽

Keyword(s):

Malaria Transmission ◽

Malaria Control ◽

Malaria Incidence ◽

Survey Methods ◽

Control Programme ◽

Malaria Control Programme ◽

Nicobar Island ◽

Cross Sectional Survey ◽

Community Knowledge ◽

Nicobar Islands

Andaman and Nicobar Islands has historically been known for its high malaria transmission in the past. The aftermath of tsunami (2004), increased its risk and vulnerability, due to stagnant water bodies. Anopheles sundaicus is the predominant vector responsible for the perennial transmission of malaria in these islands. The Great Nicobar Island being one of the Tehsil of Nicobar District, is an important tourism centre attracting both national and international visitors in large numbers throughout the year. Community knowledge on malaria and its vectors is a pre-requisite for any successful malaria control programme. In order to determine the community knowledge regarding malaria transmission and control, a cross sectional survey was carried out in three villages of Great Nicobar Island, having high malaria incidence. A total of 170 individuals, viz., 70 Nicobarese (tribal) and 100 non-Nicobarese (non-tribal) were enquired. Both quantitative (KAP) and qualitative (FGD) survey methods were employed to collect the data. Among the Nicobarese, 98.6% were aware of the disease, 94.2% had knowledge of its symptoms. Similar observation was found among the non-Nicobarese community. However, knowledge on the bionomics of malaria vector and transmission was observed to be low in both the groups (17-23%). In the community based awareness campaign, field visits to the vector breeding sites is to be emphasized. Involvement of Self Help Groups and school children would facilitate easy dissemination of knowledge on vectors to the community. This improved awareness could help in reducing vector proliferation and form a basis for effective implementation of malaria control programme.

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Community-based molecular and serological surveillance of subclinical malaria in Myanmar

BMC Medicine ◽

10.1186/s12916-021-01993-8 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Katherine O’Flaherty ◽

Win Han Oo ◽

Sophie G. Zaloumis ◽

Julia C. Cutts ◽

Kyaw Zayar Aung ◽

...

Keyword(s):

Malaria Transmission ◽

Quantitative Polymerase Chain Reaction ◽

Dried Blood Spots ◽

Molecular Testing ◽

Sample Collection ◽

Malaria Surveillance ◽

Surveillance Network ◽

Targeted Interventions ◽

Residual Malaria Transmission ◽

Serological Surveillance

Abstract Background In the Greater Mekong Subregion (GMS), current malaria surveillance strategies rely on a network of village health volunteers (VHVs) reporting the results of rapid diagnostic tests (RDTs), known to miss many asymptomatic infections. Integration of more sensitive diagnostic molecular and serological measures into the VHV network may improve surveillance of residual malaria transmission in hard-to-reach areas in the region and inform targeted interventions and elimination responses. However, data on residual malaria transmission that would be captured by these measures in the VHV-led testing and treatment surveillance network in the GMS is unknown. Methods A total of 114 VHVs were trained to collect dried blood spots from villagers undergoing routine RDTs as part of VHV-led active and passive case detection from April 2015 to June 2016. Samples were subjected to molecular testing (quantitative polymerase chain reaction [qPCR]) to determine Plasmodium falciparum and P. vivax infection and serological testing (against P. falciparum and P. vivax antigens) to determine exposure to P. falciparum and P. vivax. Results Over 15 months, 114 VHVs performed 32,194 RDTs and collected samples for molecular (n = 13,157) and serological (n = 14,128) testing. The prevalence of molecular-detectable P. falciparum and P. vivax infection was 3.2% compared to the 0.16% prevalence of Plasmodium spp. by RDT, highlighting the large burden of infections undetected by standard surveillance. Peaks in anti-P. falciparum, but not P. vivax, merozoite IgG seroprevalence coincided with seasonal P. falciparum transmission peaks, even in those with no molecularly detectable parasites. At the individual level, antibody seropositivity was associated with reduced odds of contemporaneous P. falciparum (OR for PfCSP 0.51 [95%CI 0.35, 0.76], p = 0.001, PfAMA1 0.70 [95%CI 0.52, 0.93], p = 0.01, and PfMSP2 0.81 [95%CI 0.61, 1.08], p = 0.15), but not P. vivax infection (OR PvAMA1 1.02 [95%CI 0.73, 1.43], p = 0.89) indicating a potential role of immunity in protection against molecular-detectable P. falciparum parasitaemia. Conclusions We demonstrated that integration and implementation of sample collection for molecular and serological surveillance into networks of VHV servicing hard-to-reach populations in the GMS is feasible, can capture significant levels of ongoing undetected seasonal malaria transmission and has the potential to supplement current routine RDT testing. Improving malaria surveillance by advancing the integration of molecular and serological techniques, through centralised testing approaches or novel point-of-contact tests, will advance progress, and tracking, towards malaria elimination goals in the GMS.

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