Annual Parasite Index Research Articles

Assessing receptivity to malaria using case surveillance and forest data in a near-elimination setting in northeast Thailand

BackgroundThailand aimed to eliminate malaria by 2024, and as such is planning for future prevention of re-establishment in malaria free provinces. Understanding the receptivity of local areas to malaria allows the appropriate targeting of interventions. Current approaches to assessing receptivity involve collecting entomological data. Forest coverage is known to be associated with malaria risk, as an environment conducive to both vector breeding and high-risk human behaviours.MethodsGeolocated, anonymized, individual-level surveillance data from 2011 to 2021 from the Thai Division of Vector-Borne Disease (DVBD) was used to calculate incidence and estimated Rc at village level. Forest cover was calculated using raster maps of tree crown cover density and year of forest loss from the publicly available Hansen dataset. Incidence and forest cover were compared graphically and using Spearman’s rho. The current foci classification system was applied to data from the last 5 years (2017–2021) and forest cover for 2021 compared between the classifications. A simple risk score was developed to identify villages with high receptivity.ResultsThere was a non-linear decrease in annual cases by 96.6% (1061 to 36) across the two provinces from 2011 to 2021. Indigenous Annual Parasite Index (API) and approximated Rc were higher in villages in highly forested subdistricts, and with higher forest cover within 5 km. Forest cover was also higher in malaria foci which consistently reported malaria cases each year than those which did not. An Rc > 1 was only reported in villages in subdistricts with > 25% forest cover. When applying a simple risk score using forest cover and recent case history, the classifications were comparable to those of the risk stratification system currently used by the DVBD.ConclusionsThere was a positive association between forest coverage around a village and indigenous malaria cases. Most local transmission was observed in the heavily forested subdistricts on the international borders with Laos and Cambodia, which are where the most receptive villages are located. These areas are at greater risk of importation of malaria due to population mobility and forest-going activities. Combining forest cover and recent case surveillance data with measures of vulnerability may be useful for prediction of malaria recurrence risk.

Mapping malaria transmission foci in Northeast Thailand from 2011 to 2021: approaching elimination in a hypoendemic area

BackgroundThailand is approaching local elimination of malaria in the eastern provinces. It has successfully reduced the number of cases over the past decade, but there are persistent transmission hot spots in and around forests. This study aimed to use data from the malaria surveillance system to describe the spatiotemporal trends of malaria in Northeast Thailand and fine-scale patterns in locally transmitted cases between 2011 and 2021.MethodsCase data was stratified based on likely location of infection and parasite species. Annual Parasite Index per 1000 population (API) was calculated for different categories. Time series decomposition was performed to identify trends and seasonal patterns. Statistically significant clusters of high (hot spots) and low (cold spots) API were identified using the Getis-Ord Gi* statistic. The stability of those hot spots and the absolute change in the proportion of API density from baseline were compared by case type.ResultsThe total number of confirmed cases experienced a non-linear decline by 96.6%, from 1061 in 2011 to 36 in 2021. There has been a decline in both Plasmodium vivax and Plasmodium falciparum case numbers, with only four confirmed P. falciparum cases over the last two years—a 98.89% drop from 180 in 2011. API was generally higher in Si Sa Ket province, which had peaks every 2–3 years. There was a large outbreak in Ubon Ratchathani in 2014–2016 which had a high proportion of P. falciparum reported. The proportion of cases classified increased over the study period, and the proportion of cases classed as indigenous to the village of residence increased from 0.2% to 33.3%. There were stable hot spots of indigenous and imported cases in the south of Si Sa Ket and southeast of Ubon Ratchathani. Plasmodium vivax hot spots were observed into recent years, while those of P. falciparum decreased to zero in Ubon in 2020 and emerged in the eastern part in 2021, the same year that P. falciparum hot spots in Si Sa Ket reached zero.ConclusionsThere has been a large, non-linear decline in the number of malaria cases reported and an increasing proportion of cases are classed as indigenous to the patient’s village of residence. Stable hot spots of ongoing transmission in the forested border areas were identified, with transmission likely persisting because of remote location and high-risk forest-going behaviours. Future efforts should include cross-border collaboration and continued targeting of high-risk behaviours to reduce the risk of imported cases seeding local transmission.

Descriptive, Hospital-Based, 10-Year Study of Malaria Transmission in Goa, a Southwest Indian State in the Malaria Elimination Phase.

The South Asia International Center of Excellence for Malaria Research, an NIH-funded collaborative program, investigated the epidemiology of malaria in the Indian state of Goa through health facility-based data collected from the Goa Medical College and Hospital (GMC), the state's largest tertiary healthcare facility, between 2012 and 2021. Our study investigated region-specific spatial and temporal patterns of malaria transmission in Goa and the factors driving such patterns. Over the past decade, the number of malaria cases, inpatients, and deaths at the GMC decreased significantly after a peak in 2014-2015. However, the proportion of severe malaria cases increased over the study period. Also, a trend of decreasing average parasitemia and increasing average gametocyte density suggests a shift toward submicroscopic infections and an increase in transmission commitment characteristic of low-transmission regions. Although transmission occurred throughout the year, 75% of the cases occurred between June and December, overlapping with the monsoon (June-October), which featured rainfall above yearly average, minimal diurnal temperature variation, and high relative humidity. Sociodemographic factors also had a significant association with malaria cases, with cases being more frequent in the 15-50-year-old age group, men, construction workers, and people living in urban areas within the GMC catchment region. Our environmental model of malaria transmission projects almost negligible transmission at the beginning of 2025 (annual parasitic index: 0.0095, 95% CI: 0.0075-0.0114) if the current control measures continue undisrupted.

Evaluation of Outbreak Preparedness to Prevent the Reintroduction of Malaria in Ramanagara District: A Descriptive Epidemiological Study.

Background Malaria is a vector-borne disease transmitted by female anopheline mosquitoes. It is also a multidimensional disease influenced by social factors such as poor environmental conditions and awareness gaps. India has witnessed a substantial reduction in malaria cases and has declared three regions as malaria-free, with Karnataka being one of the states. However, Karnataka witnesses significant population movement and migration, which influences the spread of malaria. Ramanagara, a district in Karnataka, reported zero indigenous cases over the past three years. Hence, we selected this district to evaluate outbreak preparedness to prevent the reintroduction of malaria. This choice underscores the district's significance as a valuable model for preventing the reintroduction of malaria. Methodology Baseline survey data on malaria cases and vector survey data were evaluated for the period spanning 2018 to 2022. The data were gathered from both the regional office and the Ramanagara district health office. In addition to the documenting system, because there was no regular submission of Form-P and Form-L of the Integrated Disease Surveillance Project and Integrated Health Information Platform from the private sector, to complete the missing data, across-sectional study was conducted among private sector practitioners and pharmacies in Ramanagara from April 2023 to June 2023. Data was collected via interviews using a malaria surveillance assessment toolkit sourced from the National Centre for Vector Borne Diseases Control and World Health Organization protocols to assess six core areas of malaria elimination. Data collected via interviews were compiled in MS Excel and analyzed using SPSS Statistics for Windows, version 26.0 (IBM Corp., Armonk, NY, USA). Results Malaria control measures in the selected district achieved >80% coverage with notable improvements in the National Health Mission-National Vector Borne Disease Control Programme fund utilization, logistics availability, and physical performance over the past five years. The Annual Parasite Index was <1 at 0.0061 in 2018 and 0.0017 in 2022. The annual blood examination rate was consistently >10 from 22.05 in 2018 to 24.36 in 2022. The primary vectors identified were Anopheles culicifacies and Anopheles stephensi. In 2018, there were six cases of Plasmodium vivax and one case of Plasmodium falciparum reported as imported cases. In 2021 and 2022, two cases of P. vivax were reported. Notably, there were no instances of mixed infections or indigenous cases documented from 2018 to 2022 Conclusions Although the level of outbreak preparedness in the region is satisfactory, the effectiveness of vector control measures appears to be lacking. Increased government funding is needed along with comprehensive training and workshops for healthcare workers. Adequate financial resources and enhanced skills among healthcare workers are crucial to reinforce the existing efforts to control vectors and prevent potential outbreaks effectively.

IJCM_234A: Malaria Surveillance System Assessment in Jashpur district, Chhattisgarh State, India, January - March 2023

Background: Globally in 2021, 247 million malaria cases were reported from 84 malaria endemic countries. India is committed to eliminate malaria by year 2030. India reported &gt;160,000 malaria cases in 2021 and 2022; 65% cases from four states-West Bengal, Chhattisgarh, Orrisa and Jharkhand. Objectives: We assessed malaria surveillance system in Jashpur district to describe epidemiology of reported malaria cases, for its strengths and weaknesses and to provide evidence-based recommendations. Methodology: We analyzed surveillance data for the year 2022. We assessed timeliness and completeness attributes of the system using US CDC guidelines for evaluating the surveillance system of the five randomly selected reporting units (RUs) for January-March 2023. We reviewed surveillance data reporting portal, hospital records and interviewed key informants. We analyzed data using MS Excel and calculated frequencies and proportion Results: Jashpur reported 269 cases in 2022; 51% female, 58% among tribal community, 89% above 15 years and 90% were of plasmodium falciparum. The maximum number of cases were reported during July to November with peak in the month of August. The annual parasite index (API) per 1000 population was 0.3 for the district, however two blocks had API of &gt;0.5. All the five RUs submitted monthly reports timely. Of the ten reporting formats reviewed, 48% critical blank fields were not filled. Conclusion: Malaria surveillance system in Jashpur detected cases largely among tribal community, identified high burden blocks with good timeliness but require improvement in complete information. We recommended district to focus preventive public health measures in high burden blocks and orient the laboratory technicians for complete data entry in line list of cases.

Situational Analysis of Malaria Incidence Under Integrated Malaria Service in Hotspot Township - Minbya Township, Rakhine State, Myanmar, 2017-2020.

Malaria is a significant public health concern and tropical disease, particularly affecting Myanmar within the Greater Mekong Subregion. The annual parasite index (API) exceeds 1 per 10,000 population in the northern seven townships of Rakhine State, with Minbya Township designated as a high-burden area for malaria by the World Health Organization (WHO) Myanmar and the National Malaria Control Programme (NMCP). Since 2017, the Malaria reduction intensification plan has been in place in this township to combat the high disease transmission rates. This study aims to assess the malaria epidemiology in Minbya Township from 2017 to 2020 under the intensification plan for elimination, as well as to evaluate the effectiveness of the integrated strategy in reducing cases in hotspot areas. The study utilized a surveillance study design to collect secondary data from the Malaria surveillance system (MSS) and the epidemiologic monitoring dashboard of Minbya Township, Maruk-U District, located in Rakhine State. Since 2017, the Malaria prevention and control (P&C) Program in Minbya Township has successfully decreased malaria morbidity, eliminated malaria-related deaths, and bolstered malaria testing capabilities through the participation of village health volunteers (VHVs). Approximately 87% of malaria prevention and control services are executed by the township's malaria elimination and disease control programs, with additional support from stakeholders. The API dropped from 13 in 2017 to 2.5 in 2020, with Plasmodium vivax being the most prevalent malaria species, accounting for 55% of cases. The study suggests that early diagnosis and promotion of artemisinin-based combination treatment (ACT), along with strategic planning including expanding active case detection in rural health centers and implementing a community-based integrated healthcare approach, are effective and efficient strategies for malaria elimination.

Malaria control – lessons learned from trends of Malaria indices over three decades in Karnataka, India

BackgroundKarnataka is one of the largest states in India and has a wide range of geographical terrains, ecotypes, and prevalence of malaria. It experiences a voluminous influx and efflux of people across the state that affects the spread of malaria. The state deployed focused intervention measures keeping the national objective of malaria elimination as the foremost priority. This brought down malaria cases below a thousand by the year 2021. Furthermore, the state is motivated toward malaria elimination by 2025. This study analyzes the trends in malaria indices over the past three decades in the state and highlights the key intervention measures that impacted the reduction in the malaria burden.MethodsData from 1991 to 2021 at the district level was collected from the archives of Regional Office for Health & Family Welfare (ROH&FW), Bangalore. Time-tend analysis on this data was conducted after categorization into three decades. Sequence plots were then plotted on the moving average of Annual Parasite Index for all those three decades. Generalized estimating equation model with Poisson distribution were used to evaluate difference in these indicators with pre and post interventions like LLIN, RDT with ACT and Guppy and Gambusia fishes.ResultsMalaria burden across the state has consistently declined over the last three decades with few years of exception. This has coincided with the mortality also steadily declining from 2006 and culminating in zero malaria deaths reported from 2011 to 2019. Morbidity had drastically reduced from the hundred-thousand (1993–2003) to ten thousand (2004–2016) thousands (2017–2020) of cases in this period and less than thousand cases were reported by 2021. Generalized estimating equation (GEE) model revealed significant difference of incidence risk ratio of malaria incidence and deaths, post introduction of interventions like LLIN, RDT with ACT and Guppy and Gambusia fishes, indicating these three as important interventions for reducing the malaria burden. Time trend analysis revealed a linear decreasing trend in malaria cases during 2011–2021 decade.ConclusionsA linear decreasing trend in malaria cases was observed during 2011–2021 decade. LLIN, RDT with ACT and Guppy and Gambusia fish’s interventions significantly helped in reducing the state malaria burden.

Socioecological risk factors associated with Malaria in Pregnancy in an endemic state of India: a retrospective study

IntroductionMalaria in Pregnancy (MiP) has significant adverse effects on both mother and fetus. Pregnant women in regions with unstable malaria transmission are three times more vulnerable to infection. This study...

Natural Infection of Nyssorhynchus darlingi and Nyssorhynchus benarrochi B with Plasmodium during the Dry Season in the Understudied Low-Transmission Setting of Datem del Marañon Province, Amazonian Peru.

The persistence of malaria hotspots in Datem del Marañon Province, Peru, prompted vector control units at the Ministry of Health, Loreto Department, to collaborate with the Amazonian International Center of Excellence for Malaria Research to identify the main vectors in several riverine villages that had annual parasite indices > 15 in 2018-2019. Anophelinae were collected indoors and outdoors for two 12-hour nights/community during the dry season in 2019 using human landing catch. We identified four species: Nyssorhynchus benarrochi B, Nyssorhynchus darlingi, Nyssorhynchus triannulatus, and Anopheles mattogrossensis. The most abundant, Ny. benarrochi B, accounted for 96.3% of the total (7,550/7,844), of which 61.5% were captured outdoors (4,641/7,550). Six mosquitoes, one Ny. benarrochi B and five Ny. darlingi, were infected by Plasmodium falciparum or Plasmodium vivax. Human biting rates ranged from 0.5 to 592.8 bites per person per hour for Ny. benarrochi B and from 0.5 to 32.0 for Ny. darlingi, with entomological inoculation rates as high as 0.50 infective bites per night for Ny. darlingi and 0.25 for Ny. benarrochi B. These data demonstrate the risk of malaria transmission by both species even during the dry season in villages in multiple watersheds in Datem del Marañon province.

Survei Demam Secara Massal Berhasil Mengendalikan Wabah Malaria Di Pulau Bungin Kabupaten Sumbawa Nusa Tenggara Barat : Pelajaran Tentang Pentingnya Deteksi Agresif Di Salah Satu Pulau Terpenting Di Dunia

Bungin Island is a very small island where population density is high, with a total population of 3,287 in a 2 kilometer-square area. The Annual Parasite Index (API) on Bungin Island in 2006 was 16,0 per thousand people. Outbreaks of malaria in Bungin Island are correlated with several controllable factors. The goal of this study is to aggressively detect and treat malaria, as well as to identify the factors that contribute to malaria outbreaks. Data was collected from the resident of Bungin Island who came to Sub-Primary Health Center Bungin Island in October 1, 2007. The data collection when outbreak malaria occurs, consisted of anamnesis, physical examination and test for type of malaria. A finger prick blood sample was collected and tested with rapid diagnostic test (RDT) for type of plasmodium. Treatment base on standard treatment for malaria from Indonesian Health Department was given to the subjects were malaria positive. The total 201 subjects was tested by RDT, in which 93 positive malaria (46,27%). Most of them were infected by Plasmodium vivax (97.85%) and only 2 subjects were infected by Plasmodium falciparum (2.15%). There were 23 subjects (24.27%) showed malaria positive without clinical symptoms. The subjects positive malaria with clinical symptoms, 8.57% were found to have spleenomegaly and 7.14% were found to have hepatomegaly. Incidence of malaria decrease siginifantly in few week after aggresive detection and appropriate treatment. A few years later, malaria incidence was disappeared. The incidence of malaria in Bungin Island was high when an outbreak occured. Aggressive detection with mass blood survey could find asymptomatic malaria in the population and appropriate treatment would decrease positive malaria until it disappeared.

Malaria hotspots and climate change trends in the hyper-endemic malaria settings of Mizoram along the India–Bangladesh borders

India has made tremendous progress in reducing malaria mortality and morbidity in the last decade. Mizoram State in North-East India is one of the few malaria-endemic regions where malaria transmission has continued to remain high. As Mizoram shares international borders with Bangladesh and Myanmar, malaria control in this region is critical for malaria elimination efforts in all the three countries. For identifying hotspots for targeted intervention, malaria data from 385 public health sub-centers across Mizoram were analyzed in the Geographic Information System. Almost all the sub-centers reporting high Annual Parasite Index (> 10) are located in Mizoram’s districts that border Bangladesh. Getis-Ord Gi* statistic shows most of the sub-centers located along the Bangladesh border in the Lawngtlai and Lunglei districts to be the malaria hotspots. The hotspots also extended into the Mamit and Siaha districts, especially along the borders of Lawngtlai and Lunglei. Analysis of terrain, climatic, and land use/land cover datasets obtained from the Global Modelling and Assimilation Office and satellite images show Mizoram’s western part (Lawngtlai, Lunglei, and Mamit districts) to experience similar topographic and climatic conditions as the bordering Rangamati district in the Chittagong division of Bangladesh. Climatic trends in this region from 1981 to 2021, estimated by the Mann–Kendall test and Sen's slope estimates, show an increasing trend in minimum temperature, relative humidity, rainfall, and the associated shift of climatic pattern (temperate to tropical monsoon) could facilitate malaria transmission. The quasi-Poisson regression model estimates a strong association (p < 0.001) between total malaria cases, temperature range, and elevation. The Kruskal–Wallis H test shows a statistically significant association between malaria cases and forest classes (p < 0.001). A regional coordination and strategic plan are required to eliminate malaria from this hyper-endemic malaria region of North-East India.

Faktor Risiko Penggunaan Kelambu Long Lasting Insectiside Nets terhadap Kejadian Malaria

The Annual Parasite Index (API) of the Genyem Health Center in 2021 is 117 per 1,000 population. This figure is very high when you look at the government's malaria control target towards malaria elimination in 2030. Papua is free of malaria (API=1/1,000). This survey study was conducted to observe the level of damage to the long lasting insecticide net (LLIN) used by 162 malaria sufferers to prevent the incidence of malaria. Each respondent has been given a mosquito net in 2021 and then each one LLIN mosquito net. The results of the evaluation of the condition of the level of damage to the stage I LLIN mosquito nets showed that the mosquito nets used by malaria patients were mostly damaged at the level of damage to size 1 (r=&lt;1 cm) as many as 18 mosquito nets (11.1%). The other levels of damage were each size 2 (r=1-3 cm) with 8 mosquito nets (4.9%), the size of the damage size 3 (r=4-5 cm) with 5 mosquito nets (3.1%), the size of the damage size 4 (r=&gt;5 cm) 3 mosquito nets (1.9%), 8 mosquito nets that were not found or missing (4.9%). The results of in-depth interviews found that the damaged LLIN mosquito nets were caused by rat bites, attracted by nails, damaged during washing, burned by respondents due to itching (skin sensitivity effect), and were converted to kill fruit ants on rambutan trees, used to catch fish. Several LLIN mosquito nets were not found or were lost because the respondent gave LLIN mosquito nets to other family members who live elsewhere.The distribution of LLIN mosquito nets that are distributed to the community to prevent the bite of the Anopheles malaria mosquito needs to be done by providing counseling on how to use and care for LLIN mosquito nets.

Trend of malaria incidences and its association with rainfall in Kalahandi District of Odisha, India.

In Odisha, Kalahandi is one of the most exposed and vulnerable districts to malaria incidences due to its poor socioeconomic condition and extreme climate. The study aimed to explore the temporal characteristics of malaria incidences in Kalahandi and to identify its relationship with rainfall for the period from 2011 to 2018. Out of the total blood films examined, 8.84% were found positive in Kalahandi between 2011 and 2018. Plasmodium falciparum is the most dominant species accounted 88.3% of the total cases. Very high mean annual parasitic index (API) >15 is recorded throughout the study years. The highest incidences are recorded in the monsoon season followed by postmonsoon. The correlation value of the annual blood examination rate with P. falciparum, Plasmodium vivax, and API has shown a very high positive correlation. Rainfall shows a (+) correlation with malaria incidences in the cold (0.47) and hot seasons (0.01) and (-) correlation in the monsoon (-0.54) and postmonsoon season (-0.54).

Linkages between malaria and malnutrition in co-endemic regions of India

IntroductionMalaria and malnutrition are key public health challenges in India. However, the relationship between them is poorly understood. Here, we aimed to elucidate the potential interactions between the two health...

Malaria and environmental, socioeconomics and public health conditions in the municipality of São Félix do Xingu, Pará, Eastern Amazon, Brazil: An ecological and cross-sectional study.

Malaria is a parasitosis conditioned by several factors. This study sought to analyze the spatial distribution of malaria considering environmental, socioeconomic, and political variables in São Félix do Xingu, Pará, Brazil, from 2014 to 2020. Epidemiological, cartographic, and environmental data were obtained from the Ministry of Health, Brazilian Geographical and Statistical Institute, and National Space Research Institute. Statistical and spatial distribution analyses were performed using chi-squared tests of expected equal proportions and the kernel and bivariate global Moran's techniques with Bioestat 5.0 and ArcGIS 10.5.1. The highest percentage of cases occurred in adult males with brown skin color, mainly placer miners, with a primary education level, living in rural areas, who were infected with Plasmodium vivax and with parasitemia of two or three crosses as diagnosed by the thick drop/smear test. The disease had a non-homogeneous distribution, with distinct annual parasite indices associated with administrative districts and clusters of cases in locations with deforestation, mining, and pastures close to Conservation Units and Indigenous Lands. Thus, a direct relationship between areas with cases and environmental degradation associated with land use was demonstrated, along with the precarious availability of health services. Pressure on protected areas and epidemiological silence in Indigenous Lands were also noted. Environmental and socioeconomic circuits were identified for development of diseases associated with precarious health services in the municipality. These findings highlight the need to intensify malaria surveillance and contribute to the systematic knowledge of malaria's epidemiology by considering the complexity of its conditioning factors.

Challenges in Understanding the Bionomics of Indian Malaria Vectors.

Many factors influence the success or failure of malaria vector control program such as political will, leadership, sustained funding, robustness of healthcare system and others. In addition, updated knowledge and information about the triad of host, parasite, and vector is of paramount importance. Vector bionomics studies that determine mosquito behavior in terms of feeding, resting, biting, mating, breeding, longevity, vectorial capacity, and response to different insecticides are a step towards enhancing our understanding. In the present work, we have compiled studies conducted in India over the past two decades (2000-2020) to identify gaps in our knowledge of malaria vector bionomics and the research that needs to be done in the future. We retrieved district-level data of India's six primary malaria vector species. According to our findings, vector bionomics studies have been undertaken in ∼50% and ∼15% of the country's high (annual parasite index >1) and low (annual parasite index <1) malaria-endemic districts respectively. Most of the research studies focused on mosquito density, insecticide susceptibility status, and parasite detection, whereas other vital bionomics parameters were neglected. Surveys conducted were incomplete, and vector bionomics data were not captured sufficiently. The absence of vector bionomics data can be a blind spot and the lack or inadequate understanding of vector bionomics can lead to use of inappropriate vector control tools. Thus, there is an urgent need to initiate comprehensive bionomics studies on India's primary and secondary malaria vectors.

MALARIA INCIDENCE IN EAST KUTAI, EAST KALIMANTAN, INDONESIA 2016: AN EPIDEMIOLOGY STUDY

Highlights: 1. Most malaria infections found in East Kutai Regency were found within the male group and had high contact with forest areas.2. Malaria infections were found predominantly in the male group aged 25 to 34 years old.3. Most of the malaria infections found were caused by Plasmodium vivax. Abstract: Background: Malaria is endemic in Indonesia and knowing the factors that are involved in malaria infection will help the development of surveillance, prevention, and disease control. Objective: This study aimed to identify the profile of malaria infection and the vectors known in East Kutai Regency, Indonesia, in 2016. Material and Method: This research was a descriptive observational study with a cross-sectional design. The sample used was taken from the 2016 annual report of The Health Office, East Kutai Regency. We evaluated malaria indicators, disease distribution, incidence (age, sex, and occupation), plasmodium species found and known vectors. Result: In 2016, there were 55 confirmed cases of malaria infection in East Kutai. The Annual Parasite Index was 0.16 per 1,000. Malaria patients were dominated by males (85.5%), aged between 25-34 years old with a mean age of 29.56 years. Most of the patients lived in Rantau Pulung (41.8%). Most of the patients had work that had high contact with forest areas (70.9%). Most of the patients were infected with Plasmodium vivax (58.2%). Identified vectors were Anopheles balabacensis which was found in Kaliorang District. Conclusion: The East Kutai Regency was classified as Low Case Incidence Area with most cases found in males of 24 to 34 years old whose work had high contact with forest areas. The identified plasmodium species were Plasmodium vivax and Plasmodium falciparum while the identified vector was Anopheles balabacensis.

Supervised versus unsupervised primaquine radical cure for the treatment of falciparum and vivax malaria in Papua, Indonesia: a cluster-randomised, controlled, open-label superiority trial

SummaryBackgroundThere is a high risk of Plasmodium vivax recurrence in patients treated for Plasmodium falciparum malaria in co-endemic areas. Primaquine radical cure has the potential to reduce P vivax recurrences in patients presenting with P falciparum as well as P vivax malaria but is undermined by poor adherence to the currently recommended 14-day regimen. We aimed to assess the efficacy and safety of supervised versus unsupervised primaquine radical cure in patients presenting with uncomplicated malaria.MethodsWe did a cluster-randomised, controlled, open-label superiority trial in Papua, Indonesia. 21 clusters of village health posts, matched by annual parasite index, were randomly assigned (1:1) to treat patients (age >12 months and body weight >5 kg) presenting with confirmed uncomplicated P falciparum or P vivax malaria with oral dihydroartemisinin–piperaquine plus either a supervised or unsupervised 14-day course of oral primaquine (0·5 mg/kg per day). Patients in the supervised group were supervised taking their primaquine dose on alternate days. Patients were followed-up for 6 months and those who presented again with malaria were retreated with the same drug regimen. Masking was not possible due to the nature of the study. The primary outcome was the incidence risk of P vivax malaria over 6 months, assessed in the modified intention-to-treat population (all patients who were assigned to a treatment group, excluding patients who were lost to follow-up after their first visit). This trial is now complete, and is registered with ClinicalTrials.gov, NCT02787070.FindingsBetween Sept 14, 2016, and July 31, 2018, 436 patients were screened for eligibility and 419 were enrolled; 223 (53%) patients in 11 clusters were assigned to supervised primaquine treatment and 196 (47%) in ten clusters to unsupervised primaquine treatment. 161 (72%) of 223 patients in the supervised group and 151 (77%) of 196 in the unsupervised group completed 6 months of follow-up. At 6 months, the incidence risk of P vivax recurrence in the supervised group was 29·7% (95% CI 16·4–49·9) versus 55·8% (32·3–81·8) in the unsupervised group (hazard ratio 0·23 [95% CI 0·07–0·76]; p=0·016). The incidence rate for P vivax recurrence was 539 (95% CI 390–747) infections per 1000 person-years in the supervised group versus 859 (673–1096) in the unsupervised group (incidence rate ratio 0·63 [95% CI 0·42–0·94]; p=0·025). The corresponding rates in the 224 patients who presented with P falciparum malaria were 346 (95% CI 213–563) and 660 (446–977; incidence rate ratio 0·52 [95% CI 0·28–0·98]; p=0·043). Seven serious adverse events were reported (three in the supervised group, four in the unsupervised group), none of which were deemed treatment-related, and there were no deaths.InterpretationIn this area of moderate malaria transmission, supervision of primaquine radical cure treatment reduced the risk of P vivax recurrence. This finding was apparent for patients presenting with either P falciparum or P vivax malaria. Further studies are warranted to investigate the safety and efficacy of radical cure for patients presenting with uncomplicated falciparum malaria in other co-endemic areas.FundingThe Bill & Melinda Gates Foundation, Wellcome Trust, and Department of Foreign Affairs and Trade of the Australian Government.TranslationFor the Indonesian translation of the abstract see Supplementary Materials section.

Production of Urban Space and the occurrence of malaria in the Brazilian Amazon: the Porto Velho case.

Due to intense ongoing urbanization in the Amazon, the urban pattern of malaria may be changing, both in its spatial distribution and epidemiological profile. The purpose of this paper is to analyze how the process of production of urban space in Porto Velho, the capital of the state of Rondonia, Brazil has contributed to the occurrence and maintenance of urban malaria. Using data collected from the Malaria Epidemiological Surveillance System (SIVEP-Malaria), we calculated malaria indices for the districts of Porto Velho from 2005 to 2018. We also developed two typologies for classifying urban space based on functional characteristics and features of the landscape. While the former considers characteristics of urban space in Porto Velho, the latter is based on suitability for malaria vectors. We found that the annual parasite index declined in Porto Velho during the study period. However, changes in the index were not uniform across the districts of the city. Periurban areas showed no decline in the index, which we attribute to these areas' high vegetation density and hydrological characteristics.

The malaria burden of Amerindian groups of three Venezuelan states: a descriptive study based on programmatic data

BackgroundFifty-three percent of all cases of malaria in the Americas in 2019 came from Venezuela, where the epidemic is heavily focused south of the Orinoco river, and where most of the country’s Amerindian groups live. Although the disease is known to represent a significant public health problem among these populations, little epidemiological data exists on the subject. This study aims to provide information on malaria incidence, geospatial clustering, and risk factors associated to Plasmodium falciparum infection among these groups.MethodsThis is a descriptive study based on the analysis of published and unpublished programmatic data collected by Venezuelan health authorities and non-government organizations between 2014 and 2018. The Annual Parasite Index among indigenous groups (API-i) in municipalities of three states (Amazonas, Bolivar, and Sucre) were calculated and compared using the Kruskal Wallis test, risk factors for Plasmodium falciparum infection were identified via binomial logistic regression and maps were constructed to identify clusters of malaria cases among indigenous patients via Moran’s I and Getis-Ord’s hot spot analysis.Results116,097 cases of malaria in Amerindian groups were registered during the study period. An increasing trend was observed between 2014 and 2016 but reverted in 2018. Malaria incidence remains higher than in 2014 and hot spots were identified in the three states, although more importantly in the south of Bolivar. Most cases (73.3%) were caused by Plasmodium vivax, but the Hoti, Yanomami, and Eñepa indigenous groups presented higher odds for infection with Plasmodium falciparum.ConclusionMalaria cases among Amerindian populations increased between 2014 and 2018 and seem to have a different geographic distribution than those among the general population. These findings suggest that tailored interventions will be necessary to curb the impact of malaria transmission in these groups.