The diversity of Anopheles blood feeding patterns suggests different malaria protection strategies in different localities

Background: Malaria is a significant health burden for many countries worldwide. Insecticide-treated bed nets and mosquito repellent are considered effective methods for preventing Anopheles bites. However, changes in the biological properties of the vector have led to a reduction in their effectiveness. The vector has been studied, but the behaviour has been poorly examined. Therefore, this study aims to investigate the importance of primary vector activity for selecting an appropriate malaria protection strategy. Methods: Initially, active case detection (ACD) was carried out in western and eastern parts of Indonesia, Jambi and Sumba, to confirm their endemicity level. According to the 2016 national health report of Indonesia, Jambi has an annual parasite index (API) of 0.14 and Sumba has an API of 5.41. A series of entomological observations were carried out to compare the biting activity of Anopheles vectors in two localities, with a total of 216 houses and 216 catchers (108 at each study site). Results: The results indicated that endemicity at the sub-district level is higher than that at the provincial level. Only Anopheles balabacensi was found to be exophagic. Multiple comparisons found different biting times between the sites, suggesting that early evening (18.00-20.00) is most likely to be the time when mosquitoes transmit the Plasmodium parasite in Jambi, while during sleeping hours (21.00-01.00) is the peak biting time of Anopheles mosquitoes in Sumba. Conclusions: The study demonstrates the importance of Anopheles species blood feeding patterns in selecting an appropriate malaria protection strategy.

Knowledge, Attitudes, Practices and Risk factors about Malaria in High Endemic Rural Eastern Tanzania

Background: Understanding area-specific knowledge, attitudes, practices and demographic risk factors towards malaria is becoming critical for designing appropriate awareness and control strategies. Methods: A cohort of respondents from 243 randomly selected households across 3 villages in eastern Tanzania was assessed using a standard questionnaire and direct observation.Results: Fifty-three percent of respondents cited Anopheles mosquitoes that were responsible for transmitting malaria, and 85% of those explicitly cited female Anopheles mosquitoes. The rest (47%) knew that malaria is transmitted by a mosquito but could not name it. Commonly cited mosquito breeding sites were water bodies (75%) and rubbish (24%). Majority (61%) knew that the under-fives were most vulnerable to malaria. ITNs were mostly (64%) cited as a means of malaria control. Commonly cited malaria mosquito entry routes were windows (46%), eave opening (10%) and opening on the walls (4%). Majority (70%) confirmed malaria at the health facility. The rest (30%) relied on symptoms. Majority (96%) preferred modern antimalarials. Seventy-nine percent of the respondents owned at least one ITN. Cooking was done predominantly (77%) outdoors, finished cooking and went to bed after 20:00h. Most (58%) respondents still attended night-time outdoor communal gatherings without malaria protection. Conclusions: The current study indicate that majority of participants were aware that Anopheles mosquitoes were responsible for transmitting malaria, they bred in water, under-five children were most vulnerable to malaria, and ITNs constituted the most deployed control measure. Most respondents preferred confirming malaria at the health facility and treatment with modern antimalarials. Yet, the rate of self-diagnosis and self-medication, as well as inappropriate use of bednets requires great improvement. Demographic risk factors for early- and/or outdoor-transmission included night-time outdoor cooking and attending communal gatherings without malaria protection. The findings warrant a subsequent study to show a causal link between night-time outdoor activities, vector biting patterns and malaria prevalence.

The diversity of Anopheles blood feeding patterns suggests different malaria protection strategies in different localities

Background: Malaria is a significant health burden for many countries worldwide. Insecticide-treated bed nets and mosquito repellent are considered effective methods for preventing Anopheles bites. However, changes in the biological properties of the vector have led to a reduction in their effectiveness. Most published studies have only investigated the human population factor, not the dynamics of vector behavior. Therefore, this study aims to investigate the importance of primary vector activity for selecting an appropriate malaria protection strategy. Methods: Initially, active case detection (ACD) was carried out in western and eastern parts of Indonesia, Jambi and Sumba, to confirm their endemicity level. According to the 2016 national health report of Indonesia, Jambi has an annual parasite index (API) of 0.14 and Sumba has an API of 5.41. A series of entomological observations were carried out to compare the biting activity of Anopheles vectors in two localities, with a total of 216 houses and 216 catchers (108 at each study site). Results: The results indicated that endemicity at the sub-district level is higher than that at the provincial level. Only Anopheles balabacensi was found to be exophagic. Multiple comparisons found different biting times between the sites, suggesting that early evening (18.00-20.00) is most likely to be the time when mosquitoes transmit the Plasmodium parasite in Jambi, while during sleeping hours (21.00-01.00) is the peak biting time of Anopheles mosquitoes in Sumba. Conclusions: The study demonstrates the importance of Anopheles species blood feeding patterns in selecting an appropriate malaria protection strategy.

Longitudinal analysis of naturally acquired antibodies to PfEMP1 CIDR domain variants and their association with malaria protection

ABSTRACTMalaria pathogenicity is determined, in part, by the adherence of Plasmodium falciparum infected erythrocytes to the microvasculature mediated via specific interactions between PfEMP1 variant domains to host endothelial receptors. Naturally acquired antibodies against specific PfEMP1 variants can play an important role in clinical protection against malaria. We evaluated IgG responses against a repertoire of PfEMP1 CIDR domain variants to determine the rate and order of variant-specific antibody acquisition and their association with protection against febrile malaria in a prospective cohort study conducted in an area of intense, seasonal malaria transmission. Using longitudinal data, we found that IgG to the pathogenic domain variants CIDRα1.7 and CIDRα1.8 were acquired the earliest. Furthermore, IgG to CIDRγ3 was associated with reduced prospective risk of febrile malaria and recurrent malaria episodes. Future studies will need to validate these findings in other transmission settings and determine the functional activity of these naturally acquired CIDR variant-specific antibodies.

The diversity of Anopheles blood feeding patterns suggests different malaria protection strategies in different localities

Background: Malaria is a significant health burden for many countries worldwide. Insecticide-treated bed nets and mosquito repellent are considered effective methods for preventing Anopheles bites. However, changes in the biological properties of the vector have led to a reduction in their effectiveness. Most published studies have only investigated the human population factor, not the dynamics of vector behavior. Therefore, this study aims to investigate the importance of primary vector activity for selecting an appropriate malaria protection strategy. Methods: Initially, active case detection (ACD) was carried out in western and eastern parts of Indonesia, Jambi and Sumba, to confirm their endemicity level. According to the 2016 national health report of Indonesia, Jambi has an annual parasite index (API) of 0.14 and Sumba has an API of 5.41. A series of entomological observations were carried out to compare the biting activity of Anopheles vector in two localities, with a total of 216 houses and 216 catchers (108 in each study site). Results: The results indicated that endemicity at the sub-district level is higher than that at the provincial level. Only Anopheles balabacensi was found to be exophagic. Multiple comparisons found different biting times between the sites, suggesting that early evening (18.00-20.00) is most likely to be the time when mosquitoes transmit the Plasmodium parasite in Jambi, while during sleeping hours (21.00-01.00) is the peak biting time of Anopheles mosquitoes in Sumba. Conclusions: The study demonstrates the importance of Anopheles species blood feeding patterns in selecting an appropriate malaria protection strategy.

The diversity of Anopheles blood feeding patterns suggests different malaria protection strategies in different localities

Background: Malaria is a significant health burden for many countries worldwide. Insecticide-treated bed nets and mosquito repellent are considered effective methods for preventing Anopheles bites. However, changes in the biological properties of the vector have led to a reduction in their effectiveness. Most published studies have only investigated the human population factor, not the dynamics of vector behavior. Therefore, this study aims to investigate the importance of primary vector activity for selecting an appropriate malaria protection strategy. Methods: Initially, active case detection (ACD) was carried out in western and eastern parts of Indonesia, Jambi and Sumba, to confirm their endemicity level. According to the 2016 national health report of Indonesia, Jambi has an annual parasite index (API) of 0.14 and Sumba has an API of 5.41. A series of entomological observations were carried out to compare the biting activity of Anopheles vector in two localities, with a total of 216 houses and catchers (108 in each study site). Results: The results indicated that endemicity at the sub-district level is higher than that at the provincial level. Only Anopheles balabacensi was found to be exophagic. Multiple comparisons found different biting times between the sites, suggesting that early evening (18.00-20.00) is most likely to be the time when mosquitos transmit the Plasmodium parasite in Jambi, while during sleeping hours (21.00-01.00) is the peak biting time of Anopheles mosquitos in Sumba. Conclusions: The study demonstrates the importance of Anopheles species blood feeding patterns in selecting an appropriate malaria protection strategy.