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

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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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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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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Estimating Annual Fluctuations in Malaria Transmission Intensity and in the Use of Malaria Control Interventions in Five Sub-Saharan African Countries

American Journal of Tropical Medicine and Hygiene ◽

10.4269/ajtmh.19-0795 ◽

2020 ◽

Vol 103 (5) ◽

pp. 1883-1892

Author(s):

◽

Elisha Adeniji ◽

Kwaku Poku Asante ◽

Owusu Boahen ◽

Guillaume Compaoré ◽

...

Keyword(s):

Malaria Transmission ◽

Malaria Control ◽

Transmission Intensity ◽

African Countries ◽

Malaria Transmission Intensity ◽

Sub Saharan

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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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Ugandan stakeholder hopes and concerns about gene drive mosquitoes for malaria control: new directions for gene drive risk governance

Malaria Journal ◽

10.1186/s12936-021-03682-6 ◽

2021 ◽

Vol 20 (1) ◽

Author(s):

Sarah Hartley ◽

Robert D. J. Smith ◽

Adam Kokotovich ◽

Chris Opesen ◽

Tibebu Habtewold ◽

...

Keyword(s):

Malaria Control ◽

Stakeholder Involvement ◽

Control Programme ◽

Local Context ◽

Risk Governance ◽

Malaria Control Programme ◽

Gene Drive ◽

Structured Interviews ◽

New Directions ◽

High Level

Abstract Background The African Union’s High-Level Panel on Emerging Technologies identified gene drive mosquitoes as a priority technology for malaria elimination. The first field trials are expected in 5–10 years in Uganda, Mali or Burkina Faso. In preparation, regional and international actors are developing risk governance guidelines which will delineate the framework for identifying and evaluating risks. Scientists and bioethicists have called for African stakeholder involvement in these developments, arguing the knowledge and perspectives of those people living in malaria-afflicted countries is currently missing. However, few African stakeholders have been involved to date, leaving a knowledge gap about the local social-cultural as well as ecological context in which gene drive mosquitoes will be tested and deployed. This study investigates and analyses Ugandan stakeholders’ hopes and concerns about gene drive mosquitoes for malaria control and explores the new directions needed for risk governance. Methods This qualitative study draws on 19 in-depth semi-structured interviews with Ugandan stakeholders in 2019. It explores their hopes for the technology and the risks they believed pertinent. Coding began at a workshop and continued through thematic analysis. Results Participants’ hopes and concerns for gene drive mosquitoes to address malaria fell into three themes: (1) ability of gene drive mosquitoes to prevent malaria infection; (2) impacts of gene drive testing and deployment; and, (3) governance. Stakeholder hopes fell almost exclusively into the first theme while concerns were spread across all three. The study demonstrates that local stakeholders are able and willing to contribute relevant and important knowledge to the development of risk frameworks. Conclusions International processes can provide high-level guidelines, but risk decision-making must be grounded in the local context if it is to be robust, meaningful and legitimate. Decisions about whether or not to release gene drive mosquitoes as part of a malaria control programme will need to consider the assessment of both the risks and the benefits of gene drive mosquitoes within a particular social, political, ecological, and technological context. Just as with risks, benefits—and importantly, the conditions that are necessary to realize them—must be identified and debated in Uganda and its neighbouring countries.

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