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Comparative Medicine Jun 2024Malaria is a parasitic disease caused by protozoan species of the genus and transmitted by female mosquitos of the genus and other Culicidae. Most of the parasites of...
Malaria is a parasitic disease caused by protozoan species of the genus and transmitted by female mosquitos of the genus and other Culicidae. Most of the parasites of the genus are highly species specific with more than 200 species described affecting different species of mammals, birds, and reptiles. species strictly affecting humans are , , , and More recently, and other nonhuman primate plasmodia were found to naturally infect humans. Currently, malaria occurs mostly in poor tropical and subtropical areas of the world, and in many of these countries it is the leading cause of illness and death. For more than 100 y, animal models, have played a major role in our understanding of malaria biology. Avian species were the first to be used as models to study human malaria. Malaria parasite biology and immunity were first studied using mainly and . Rodent malarias, particularly and , have been used extensively as models to study malaria in mammals. Several species of from nonhuman primates have been used as surrogate models to study human malaria immunology, pathogenesis, candidate vaccines, and treatments. , , and are important models for studying malaria produced by and , while is used as a model for studying severe malaria. Other nonhuman primate malarias used in research are , , , , and . Very few nonhuman primate species can develop an infection with human malarias. Macaques in general are resistant to infection with , , , and . Only apes and a few species of New World monkeys can support infection with human malarias. Herein we review the most common, and some less common, avian, reptile, and mammal plasmodia species used as models to study human malaria.
PubMed: 38902006
DOI: 10.30802/AALAS-CM-24-000019 -
Antimicrobial Agents and Chemotherapy Jun 2024The emergence of clinically drug-resistant malaria parasites requires the urgent development of new drugs. Mosquitoes are vectors of multiple pathogens and have...
The emergence of clinically drug-resistant malaria parasites requires the urgent development of new drugs. Mosquitoes are vectors of multiple pathogens and have developed resistance mechanisms against them, which often involve antimicrobial peptides (AMPs). An-cecB is an AMP of the malaria-transmitting mosquito genus , and we herein report its antimalarial activity against 3D7, the artemisinin-resistant strain 803, and the chloroquine-resistant strain Dd2 . We also demonstrate its anti-parasite activity , using the rodent malaria parasite (ANKA). We show that An-cecB displays potent antimalarial activity and that its mechanism of action may occur through direct killing of the parasite or through interaction with infected red blood cell membranes. Unfortunately, An-cecB was found to be cytotoxic to mammalian cells and had poor antimalarial activity . However, its truncated peptide An-cecB-1 retained most of its antimalarial activity and avoided its cytotoxicity . An-cecB-1 also showed better antimalarial activity . Mosquito-derived AMPs may provide new ideas for the development of antimalarial drugs against drug-resistant parasites, and An-cecB has potential use as a template for antimalarial peptides.
PubMed: 38874346
DOI: 10.1128/aac.00311-24 -
Medecine Tropicale Et Sante... Mar 2024The Republic of Djibouti is located in the Horn of Africa, on the Gulf of Aden and the Bab-el-Mandeb detroit, at the southern entrance to the Red Sea. Prior to its... (Review)
Review
BACKGROUND AND JUSTIFICATION
The Republic of Djibouti is located in the Horn of Africa, on the Gulf of Aden and the Bab-el-Mandeb detroit, at the southern entrance to the Red Sea. Prior to its independence in 1977, the Republic of Djibouti was known by two names: "Côte française des Somalis" until 1967, then "Territoire Français de Afars et Issas". As part of our doctoral research on the ecology of mosquitoes in Djibouti, we noted a lack of information on the species encountered, and felt it essential to draw up a list of species before embarking on ecological monitoring. The aim of this work is to survey publications on mosquitoes in Djibouti and to synthesize data from this scientific literature in order to update the national inventory of Culicidae.
MATERIALS AND METHODS
An exhaustive search of electronic bibliographic databases (PubMed, Scopus, HAL Open Archive, Science Direct and Google Scholar) was carried out. Reference lists were filtered to access additional articles in order to obtain more data. Two keywords were used: "Djibouti" and "French Territory of Afars and Issas". A selection of scientific publications on Djibouti mosquitoes and/or diseases transmitted by mosquito vectors was made. Researches were conducted in articles selected. The names of the species listed were checked and validated by referring to the site Mosquito Taxonomic Inventory.
RESULTS
A total of 13 studies, published between 1970 and 2023, were found. Over the years, the composition of the Culicidae fauna has become well known. In part, the movement of people traveling to and from neighboring countries has been linked to the detection of new species and the reappearance of mosquito species in Djibouti. Numerous studies have been carried out over the years, including purely taxonomic studies and others focusing on the incrimination of mosquito vectors and the characterization of the pathogens they transmit. A total of 37 species, belonging to two subfamilies (Anophelinae and Culicinae), of mosquitoes divided between 7 genera and have been mentioned across the country. The number of species per genus is distributed as follows: 5 species of including 1 subspecies, 14 species of including two subspecies, 12 species of including 1 subspecies, 1 species for each of the genera and and finally 2 species respectively for the genera and Five species have been incriminated as vectors of diseases such as malaria, dengue fever, yellow fever, West Nile virus and chikungunya. Others are known for their potential role in pathogen transmission, including Zika and Rift Valley virus.
DISCUSSION - CONCLUSION
The bibliographical research enabled us to summarize the research carried out over more than half a century in the history of Djibouti, and to update the inventory of the country's mosquitoes, which now includes 37 species. Species names were reviewed and updated, and the case of was also addressed. Two species mentioned as part of the Culicidae fauna of Djibouti appeared to be doubtful and are up for discussion. These results provide a useful information base for defining vector control priorities in Djibouti. They will also inform, guide and facilitate future consultations of our database. In addition, this study will help to identify research ways on mosquitoes in Djibouti.
Topics: Animals; Culicidae; Djibouti; Mosquito Vectors
PubMed: 38846112
DOI: 10.48327/mtsi.v4i1.2024.365 -
Evolutionary Applications Jun 2024The adaptation of malaria vectors to domestic settings is directly linked to their ability to feed on humans. The strength of this species-habitat association is...
The adaptation of malaria vectors to domestic settings is directly linked to their ability to feed on humans. The strength of this species-habitat association is unequal across the species within the genus, with the major vectors being particularly dependent on humans. However, our understanding of how blood-feeding behavior interacts with and adapts to environmental settings, including the presence of humans, remains limited. Using a field-based approach, we first investigated community structure and feeding behavior patterns in domestic and sylvatic settings in La Lopé National Park in Gabon, Central Africa. We characterized the preference indices using a dual-host choice sampling approach across mosquito species, habitats, and seasons. We then quantified the plastic biting behavior of mosquito species in each habitat. We collected individuals from 16 species that exhibited significant differences in species composition and abundance between sylvatic and domestic settings. The host-seeking behavior also varied among the seven most abundant species. The general attractiveness to each host, human or animal, remained relatively constant for each species, but with significant variations between habitats across species. These variations, to more generalist and to more anthropophilic behavior, were related to seasonal changes and distance from the village, respectively. Finally, we pointed out that the host choice of major malaria vectors changed in the absence of humans, revealing a plastic feeding behavior of these species. This study highlights the effect of humans on distribution and feeding evolution. The characterization of feeding behavior in wild and domestic settings provides opportunities to better understand the interplay between genetic determinants of host preference and ecological factors. Our findings suggest that protected areas may offer alternative thriving conditions to major malaria vectors.
PubMed: 38828055
DOI: 10.1111/eva.13693 -
Malaria Journal May 2024The recent reduction in malaria burden in Côte d'Ivoire is largely attributable to the use of long-lasting insecticidal nets (LLINs). However, this progress is...
Combined use of long-lasting insecticidal nets and Bacillus thuringiensis israelensis larviciding, a promising integrated approach against malaria transmission in northern Côte d'Ivoire.
BACKGROUND
The recent reduction in malaria burden in Côte d'Ivoire is largely attributable to the use of long-lasting insecticidal nets (LLINs). However, this progress is threatened by insecticide resistance and behavioral changes in Anopheles gambiae sensu lato (s.l.) populations and residual malaria transmission, and complementary tools are required. Thus, this study aimed to assess the efficacy of the combined use of LLINs and Bacillus thuringiensis israelensis (Bti), in comparison with LLINs.
METHODS
This study was conducted in the health district of Korhogo, northern Côte d'Ivoire, within two study arms (LLIN + Bti arm and LLIN-only arm) from March 2019 to February 2020. In the LLIN + Bti arm, Anopheles larval habitats were treated every fortnight with Bti in addition to the use of LLINs. Mosquito larvae and adults were sampled and identified morphologically to genus and species using standard methods. The members of the An. gambiae complex were determined using a polymerase chain reaction technique. Plasmodium infection in An. gambiae s.l. and malaria incidence in local people was also assessed.
RESULTS
Overall, Anopheles spp. larval density was lower in the LLIN + Bti arm 0.61 [95% CI 0.41-0.81] larva/dip (l/dip) compared with the LLIN-only arm 3.97 [95% CI 3.56-4.38] l/dip (RR = 6.50; 95% CI 5.81-7.29; P < 0.001). The overall biting rate of An. gambiae s.l. was 0.59 [95% CI 0.43-0.75] biting/person/night in the LLIN + Bti arm against 2.97 [95% CI 2.02-3.93] biting/person/night in LLIN-only arm (P < 0.001). Anopheles gambiae s.l. was predominantly identified as An. gambiae sensu stricto (s.s.) (95.1%, n = 293), followed by Anopheles coluzzii (4.9%; n = 15). The human-blood index was 80.5% (n = 389) in study area. EIR was 1.36 infected bites/person/year (ib/p/y) in the LLIN + Bti arm against 47.71 ib/p/y in the LLIN-only arm. Malaria incidence dramatically declined from 291.8‰ (n = 765) to 111.4‰ (n = 292) in LLIN + Bti arm (P < 0.001).
CONCLUSIONS
The combined use of LLINs with Bti significantly reduced the incidence of malaria. The LLINs and Bti duo could be a promising integrated approach for effective vector control of An. gambiae for elimination of malaria.
Topics: Cote d'Ivoire; Bacillus thuringiensis; Animals; Anopheles; Larva; Malaria; Mosquito Control; Insecticide-Treated Bednets; Female; Mosquito Vectors; Humans; Male; Adolescent; Child, Preschool; Young Adult; Child; Adult
PubMed: 38812003
DOI: 10.1186/s12936-024-04953-8 -
Tropical Medicine and Infectious Disease May 2024Malaria is a parasitic infection that may result in an acute, life-threatening illness. It is a major public health problem in the tropical world. The disease is caused...
Malaria is a parasitic infection that may result in an acute, life-threatening illness. It is a major public health problem in the tropical world. The disease is caused by the parasites of the genus and is transmitted by female mosquitoes. Saudi Arabia is in the elimination phase of malaria control. Several parts of Saudi Arabia report cases of imported malaria among travelers and visitors. The city of Makkah in Saudi Arabia has a population of about 2.3 million. Moreover, over 6 million religious visitors from different parts of the world visit Makkah annually. During the COVID-19 outbreak, travel restrictions were enforced in Makkah to contain the spread of COVID-19. We compare the total reported cases of malaria in Makkah before, during, and after COVID-19 travel restrictions in this retrospective cross-sectional study. Data on demographics, clinical data, and laboratory parameters were collected from the medical records of the Ministry of Health, Saudi Arabia. The annual malaria incidence rates in Makkah were 29.13/million people (2018), 37.82/million people (2019), 15.65/million people (2020), 12.61/million people (2021), and 48.69/million people (2022). Most of the malaria cases in Makkah were caused by followed by . Sudan, Nigeria, Yamen, Pakistan, and India are the top five countries contributing to malaria cases in Makkah. Weekly malaria case analyses revealed that COVID-19-related travel restrictions resulted in zero malaria cases in Makkah, indicating the magnitude of the travel-related malaria burden in the city.
PubMed: 38787045
DOI: 10.3390/tropicalmed9050112 -
Parasites & Vectors May 2024Mosquitoes pose a risk to human health worldwide, and correct species identification and detection of cryptic species are the most important keys for surveillance and...
A DNA barcode reference library of Croatian mosquitoes (Diptera: Culicidae): implications for identification and delimitation of species, with notes on the distribution of potential vector species.
BACKGROUND
Mosquitoes pose a risk to human health worldwide, and correct species identification and detection of cryptic species are the most important keys for surveillance and control of mosquito vectors. In addition to traditional identification based on morphology, DNA barcoding has recently been widely used as a complementary tool for reliable identification of mosquito species. The main objective of this study was to create a reference DNA barcode library for the Croatian mosquito fauna, which should contribute to more accurate and faster identification of species, including cryptic species, and recognition of relevant vector species.
METHODS
Sampling was carried out in three biogeographical regions of Croatia over six years (2017-2022). The mosquitoes were morphologically identified; molecular identification was based on the standard barcoding region of the mitochondrial COI gene and the nuclear ITS2 region, the latter to identify species within the Anopheles maculipennis complex. The BIN-RESL algorithm assigned the COI sequences to the corresponding BINs (Barcode Index Number clusters) in BOLD, i.e. to putative MOTUs (Molecular Operational Taxonomic Units). The bPTP and ASAP species delimitation methods were applied to the genus datasets in order to verify/confirm the assignment of specimens to specific MOTUs.
RESULTS
A total of 405 mosquito specimens belonging to six genera and 30 morphospecies were collected and processed. Species delimitation methods assigned the samples to 31 (BIN-RESL), 30 (bPTP) and 28 (ASAP) MOTUs, with most delimited MOTUs matching the morphological identification. Some species of the genera Culex, Aedes and Anopheles were assigned to the same MOTUs, especially species that are difficult to distinguish morphologically and/or represent species complexes. In total, COI barcode sequences for 34 mosquito species and ITS2 sequences for three species of the genus Anopheles were added to the mosquito sequence database for Croatia, including one individual from the Intrudens Group, which represents a new record for the Croatian mosquito fauna.
CONCLUSION
We present the results of the first comprehensive study combining morphological and molecular identification of most mosquito species present in Croatia, including several invasive and vector species. With the exception of some closely related species, this study confirmed that DNA barcoding based on COI provides a reliable basis for the identification of mosquito species in Croatia.
Topics: Animals; DNA Barcoding, Taxonomic; Croatia; Mosquito Vectors; Culicidae; Electron Transport Complex IV; Anopheles; Phylogeny; Gene Library
PubMed: 38734639
DOI: 10.1186/s13071-024-06291-9 -
Bulletin of Entomological Research May 2024The Culicidae mosquito family breeds in various natural and artificial water bodies. Phytotelmata are plant structures that hold water and are used by many mosquito...
The Culicidae mosquito family breeds in various natural and artificial water bodies. Phytotelmata are plant structures that hold water and are used by many mosquito species during their life cycle. Mosquitoes are disease vectors, and phytotelmata play an important role in harbouring them. Investigating these phytotelmata will facilitate to develop appropriate site specific vector control strategy. Approximately 750 phytotelmata in 16 locations on Car Nicobar Island was examined. Mosquito larvae were collected from different habitats such as tree holes, root holes, leaf axils, and bamboo stumps. On average, the number of larvae per 10 ml of water ranged from 0.003 to 3.833. Among the 16 mosquito species identified, there were vectors of malaria (), dengue ( and ) and filariasis (), belonging to seven genera. The most common phytotelmata were coconut trees (17.5%) followed by Java apple trees (10.3%) and bamboo stumps (7.1%). The most widespread mosquito species was , followed by and , and the per cent of phytotelmata that contained these species were 42.6, 22.0, and 16.8% respectively. mosquitoes had the highest container index (6.1%) in root holes, while and mosquitoes were more frequently found in bamboo stumps. The alpha biodiversity indices indicated that the mosquito population in Car Nicobar Island was highly diverse ( = 16; DMg = 36.9). Tree holes showed the highest diversity, as all 16 species were collected from them. Assessment of phytotelmata, there is a significant relationship observed between mosquito genus, village, habitat, and tree families, on the remote island of Car Nicobar. Considering the presence of disease-transmitting mosquito vectors in the phytotelmata, these habitats should be considered when implementing control measures to eliminate mosquito-borne infections.
PubMed: 38708567
DOI: 10.1017/S0007485324000245 -
Scientific Reports Apr 2024The Plasmodium is responsible for malaria which poses a major health threat, globally. This study is based on the estimation of the relative abundance of mosquitoes, and...
The Plasmodium is responsible for malaria which poses a major health threat, globally. This study is based on the estimation of the relative abundance of mosquitoes, and finding out the correlations of meteorological parameters (temperature, humidity and rainfall) with the abundance of mosquitoes. In addition, this study also focused on the use of nested PCR (species-specific nucleotide sequences of 18S rRNA genes) to explore the Plasmodium spp. in female Anopheles. In the current study, the percentage relative abundance of Culex mosquitoes was 57.65% and Anopheles 42.34% among the study areas. In addition, the highest number of mosquitoes was found in March in district Mandi Bahauddin at 21 °C (T = 27, T = 15) average temperature, 69% average relative humidity and 131 mm rainfall, and these climatic factors were found to affect the abundance of the mosquitoes, directly or indirectly. Molecular analysis showed that overall, 41.3% of the female Anopheles pools were positive for genus Plasmodium. Among species, the prevalence of Plasmodium (P.) vivax (78.1%) was significantly higher than P. falciparum (21.9%). This study will be helpful in the estimation of future risk of mosquito-borne diseases along with population dynamic of mosquitoes to enhance the effectiveness of vector surveillance and control programs.
Topics: Animals; Anopheles; Mosquito Vectors; Polymerase Chain Reaction; Female; Plasmodium; Malaria; RNA, Ribosomal, 18S; Culex; Humans; Plasmodium falciparum; Plasmodium vivax
PubMed: 38684775
DOI: 10.1038/s41598-024-60662-x -
Vector Borne and Zoonotic Diseases... Apr 2024West Nile virus (WNV), Everglades virus (EVEV), and five species of were isolated from mosquitoes collected in the Everglades in 2016-2017. Prior studies of blood...
West Nile virus (WNV), Everglades virus (EVEV), and five species of were isolated from mosquitoes collected in the Everglades in 2016-2017. Prior studies of blood meals of mosquitoes in southern Florida have related findings to acquisition and transmission of EVEV, St. Louis encephalitis virus, and WNV, but not the viruses associated with the subgenus of the genus . In the present study, blood-fed mosquitoes were collected in the Everglades in 2016, 2017, 2021, and 2022, and from an industrial site in Naples, FL in 2017. Blood meals were identified to host species by PCR assays using mitochondrial gene. Blood meals were identified from complex and 11 mosquito species captured in the Florida Everglades and from 3 species collected from an industrial site. The largest numbers of blood-fed specimens were from , , , and . fed on mammals, birds, and reptiles, particularly American alligator. This mosquito species could transmit WNV to American alligator in the wild. acquired blood meals primarily from birds and mammals and frequently fed on medium-sized mammals and white-tailed deer. Water and wading birds were the primary avian hosts for and in the Everglades. Wading birds are susceptible to WNV and could serve as reservoir hosts. fed on five species of rodents, particularly black and hispid cotton rats. EVEV and three different species of have been isolated from the hispid cotton rat and in the Everglades. is likely acquiring and transmitting these viruses among hispid cotton rats and other rodents. The marsh rabbit was a frequent host for complex. complex, and other species could acquire Tensaw virus from rabbits. Our study contributes to a better understanding of the host and viral associations of mosquito species in southwestern Florida.
PubMed: 38648543
DOI: 10.1089/vbz.2023.0072