Tropical Medicine and Infectious Disease

Research

13 pages, 1350 KiB

Open AccessArticle

In Silico Analysis Reveals High Levels of Genetic Diversity of Plasmodium knowlesi Cell Traversal Protein for Ookinetes and Sporozoites (PkCelTOS) in Clinical Samples

by Md Atique Ahmed, Pratisthita Baruah, Ahmed Saif, Jin-Hee Han, Mohammed Al-Zharani, Syeda Wasfeea Wazid, Saad Alkahtani, Saurav J. Patgiri, Mohammed S. Al-Eissa and Fu-Shi Quan

Trop. Med. Infect. Dis. 2023, 8(8), 380; https://doi.org/10.3390/tropicalmed8080380 - 26 Jul 2023

Cited by 1 | Viewed by 1738

Abstract

The cell-traversal protein for ookinetes and sporozoites (CelTOS), expressed on the surface of ookinetes and sporozoitesin Plasmodium species, is a promising malaria vaccine candidate. CelTOS is essential for parasite invasion into mosquito midgut and human hepatocytes, thereby contributing to malaria transmission and [...] Read more.

The cell-traversal protein for ookinetes and sporozoites (CelTOS), expressed on the surface of ookinetes and sporozoitesin Plasmodium species, is a promising malaria vaccine candidate. CelTOS is essential for parasite invasion into mosquito midgut and human hepatocytes, thereby contributing to malaria transmission and disease pathogenesis. This study explores the genetic diversity, polymorphisms, haplotypes, natural selection, phylogenetic analysis, and epitope prediction in the full-length Plasmodium knowlesi CelTOS gene in clinical samples from Sarawak, Malaysian Borneo, and long-term laboratory strains from Peninsular Malaysia and the Philippines. Our analysis revealed a high level of genetic variation in the PkCelTOS gene, with a nucleotide diversity of π ~ 0.021, which was skewed towards the 3’ end of the gene. This level of diversity is double that observed in PfCelTOS and 20 times that observed in PvCelTOS from worldwide clinical samples. Tests of natural selection revealed evidence for positive selection within clinical samples. Phylogenetic analysis of the amino acid sequence of PkCelTOS revealed the presence of two distinct groups, although no geographical clustering was observed. Epitope prediction analysis identified two potential epitopes (96AQLKATA102 and 124TIKPPRIKED133) using the IEDB server and one epitope (125IKPPRIKED133) by Bcepred server on the C’ terminal region of PkCelTOS protein. Both the servers predicted a common epitope region of nine amino acid length (IKPPRIKED) peptide, which can be studied in the future as a potential candidate for vaccine development. These findings shed light on the genetic diversity, polymorphism, haplotypes, and natural selection within PkCelTOS in clinical samples and provide insights about its future prospects as a potential candidate for P. knowlesi malaria vaccine development. Full article

(This article belongs to the Special Issue Emerging Vector-Borne Diseases and Public Health Challenges)

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12 pages, 1465 KiB

Open AccessEditor’s ChoiceArticle

Comparison of Climate Change Scenarios of Rhipicephalus sanguineus sensu lato (Latreille 1806) from México and the Boarders with Central America and the United States

by David A. Moo-Llanes, Sokani Sánchez-Montes, Teresa López-Ordoñez, Karla Dzul-Rosado, Daniela Segura-Trejo, Beatriz Salceda-Sánchez and Rogelio Danis-Lozano

Trop. Med. Infect. Dis. 2023, 8(6), 307; https://doi.org/10.3390/tropicalmed8060307 - 4 Jun 2023

Cited by 1 | Viewed by 2745

Abstract

In America, the presence of Rhipicephalus sanguineus sensu stricto and Rhipicephalus linnaei has been confirmed. Both species are found in sympatry in the southern United States, northern Mexico, southern Brazil, and Argentina. The objective of this work is to evaluate the projection of [...] Read more.

In America, the presence of Rhipicephalus sanguineus sensu stricto and Rhipicephalus linnaei has been confirmed. Both species are found in sympatry in the southern United States, northern Mexico, southern Brazil, and Argentina. The objective of this work is to evaluate the projection of the potential distribution of the ecological niche of Rhipicephalus sanguineus sensu lato in two climate change scenarios in Mexico and the border with Central America and the United States. Initially, a database of personal collections of the authors, GBIF, Institute of Epidemiological Diagnosis and Reference, and scientific articles was built. The ENMs were projected for the current period and two future scenarios: RCP and SSP used for the kuenm R package, the ecological niche of R. sanguineus s.l. It is distributed throughout the Mexico and Texas (United States), along with the border areas between Central America, Mexico, and the United States. Finally, it is observed that the ecological niche of R. sanguineus s.l. in the current period coincides in three degrees with the routes of human migration. Based on this information, and mainly on the flow of migrants from Central America to the United States, the risk of a greater gene flow in this area increases, so the risk relating to this border is a latent point that must be analyzed. Full article

(This article belongs to the Special Issue Emerging Vector-Borne Diseases and Public Health Challenges)

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23 pages, 2000 KiB

Open AccessArticle

The Potential of Surveillance Data for Dengue Risk Mapping: An Evaluation of Different Approaches in Cuba

by Waldemar Baldoquín Rodríguez, Mayelin Mirabal, Patrick Van der Stuyft, Tania Gómez Padrón, Viviana Fonseca, Rosa María Castillo, Sonia Monteagudo Díaz, Jan M. Baetens, Bernard De Baets, Maria Eugenia Toledo Romaní and Veerle Vanlerberghe

Trop. Med. Infect. Dis. 2023, 8(4), 230; https://doi.org/10.3390/tropicalmed8040230 - 18 Apr 2023

Viewed by 2356

Abstract

To better guide dengue prevention and control efforts, the use of routinely collected data to develop risk maps is proposed. For this purpose, dengue experts identified indicators representative of entomological, epidemiological and demographic risks, hereafter called components, by using surveillance data aggregated at [...] Read more.

To better guide dengue prevention and control efforts, the use of routinely collected data to develop risk maps is proposed. For this purpose, dengue experts identified indicators representative of entomological, epidemiological and demographic risks, hereafter called components, by using surveillance data aggregated at the level of Consejos Populares (CPs) in two municipalities of Cuba (Santiago de Cuba and Cienfuegos) in the period of 2010–2015. Two vulnerability models (one with equally weighted components and one with data-derived weights using Principal Component Analysis), and three incidence-based risk models were built to construct risk maps. The correlation between the two vulnerability models was high (tau > 0.89). The single-component and multicomponent incidence-based models were also highly correlated (tau ≥ 0.9). However, the agreement between the vulnerability- and the incidence-based risk maps was below 0.6 in the setting with a prolonged history of dengue transmission. This may suggest that an incidence-based approach does not fully reflect the complexity of vulnerability for future transmission. The small difference between single- and multicomponent incidence maps indicates that in a setting with a narrow availability of data, simpler models can be used. Nevertheless, the generalized linear mixed multicomponent model provides information of covariate-adjusted and spatially smoothed relative risks of disease transmission, which can be important for the prospective evaluation of an intervention strategy. In conclusion, caution is needed when interpreting risk maps, as the results vary depending on the importance given to the components involved in disease transmission. The multicomponent vulnerability mapping needs to be prospectively validated based on an intervention trial targeting high-risk areas. Full article

(This article belongs to the Special Issue Emerging Vector-Borne Diseases and Public Health Challenges)

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7 pages, 280 KiB

Open AccessCommunication

Dichotomous Keys Based on Cytogenetic Data for Triatomines Reported in Brazilian Regions with Outbreaks of Orally Transmitted Chagas Disease (Pernambuco and Rio Grande Do Norte)

by Denis Vinícius de Mello, Emercio Felisberto Nhapulo, Laura Poloto Cesaretto, Julia Junqueira Alevi, Daniel Cesaretto Cristal, Giulia Montanari, Cleber Galvão and Kaio Cesar Chaboli Alevi

Trop. Med. Infect. Dis. 2023, 8(4), 196; https://doi.org/10.3390/tropicalmed8040196 - 29 Mar 2023

Cited by 3 | Viewed by 1409

Abstract

Chagas disease (CD) affects about eight million people worldwide. Brazil has the highest number of estimated cases and the largest number of deaths due to CD. Considering the recent outbreaks of oral CD involving at least 27 cases of acute CD in Pernambuco [...] Read more.

Chagas disease (CD) affects about eight million people worldwide. Brazil has the highest number of estimated cases and the largest number of deaths due to CD. Considering the recent outbreaks of oral CD involving at least 27 cases of acute CD in Pernambuco (PE) as well as 18 cases and 2 deaths in the Rio Grande do Norte (RN), we developed dichotomous keys for the identification of triatomine species in these Brazilian states based on cytogenetic data. All triatomine species could be distinguished by cytogenetic characteristics, emphasizing the importance of the newly developed taxonomic keys for the correct identification of triatomes from PE and RN, particularly for species that exhibit morphological similarities, such as Triatoma brasilensis and T. petrocchiae (present in both states) and T. maculata and T. pseudomaculata (as T. pseudomaculata has been misidentified as T. maculata in PE and RN). These alternative keys are expected to provide a useful tool for the scientific community and, above all, health agents, aimed at preventing mistakes from occurring in the identification of the vectors present in PE and RN related to CD outbreaks caused by oral infection. Full article

(This article belongs to the Special Issue Emerging Vector-Borne Diseases and Public Health Challenges)

7 pages, 890 KiB

Open AccessCommunication

Molecular Detection of Multiple Genotypes of Orientia tsutsugamushi Causing Scrub Typhus in Febrile Patients from Theni District, South India

by Krishnamoorthy Nallan, Gopinathan Rajan, Lallitha Sivathanu, Panneer Devaraju, Balaji Thiruppathi, Ashwani Kumar and Paramasivan Rajaiah

Trop. Med. Infect. Dis. 2023, 8(3), 174; https://doi.org/10.3390/tropicalmed8030174 - 16 Mar 2023

Cited by 1 | Viewed by 2458

Abstract

Scrub typhus (St) is a re-emerging mite-transmitted public health problem in Southeast Asia with escalating case incidences in the endemic areas. Though, more than 40 genotypes of the causative agent Orientia tsutsugamushi (Ot) have been documented, the information on the circulating [...] Read more.

Scrub typhus (St) is a re-emerging mite-transmitted public health problem in Southeast Asia with escalating case incidences in the endemic areas. Though, more than 40 genotypes of the causative agent Orientia tsutsugamushi (Ot) have been documented, the information on the circulating genotypes in India is scanty. A hospital-based retrospective screening was undertaken to map the circulating molecular subtypes of the etiological agent in serologically confirmed scrub typhus (St) human cases, by targeting the GroEL gene of O. tsutsugamushi using the nested polymerase chain reaction method. Nine out of 34 samples (26%) yielded positive results and DNA sequencing analysis of six positive samples out of nine revealed that the sequences were related to three major genotypes, such as Karp (HSB1, FAR1), Kato (Wuj/2014, UT76), and Kawasaki (Kuroki, Boryong, Gilliam, and Hwasung). Additionally, the St-positive samples exhibited 100% and 99.45%; 97.53% and 97.81%; 96.99% nucleotide identity with the closely related Karp, Kato, and Kawasaki-related sequences, respectively. Overall, 94% of the nucleotides were conserved, and the variable site was 20/365 (5.5%). The prevalence of multiple genotypes among human cases further stresses the need to conduct in-depth studies to map the genotypes and their clinical relevance, and the contributing risk factors for the emergence of St cases in this area. Full article

(This article belongs to the Special Issue Emerging Vector-Borne Diseases and Public Health Challenges)

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14 pages, 2451 KiB

Open AccessArticle

Aedes aegypti in Southern Brazil: Spatiotemporal Distribution Dynamics and Association with Climate and Environmental Factors

by Joice Guilherme de Oliveira, Sérgio Antônio Netto, Edenilson Osinski Francisco, Caroline Pereira Vieira, Paula Fassicolo Variza, Betine Pinto Moehlecke Iser, Tamara Nunes Lima-Camara, Camila Lorenz and Josiane Somariva Prophiro

Trop. Med. Infect. Dis. 2023, 8(2), 77; https://doi.org/10.3390/tropicalmed8020077 - 20 Jan 2023

Cited by 2 | Viewed by 3075

Abstract

In Brazil, the mosquito Aedes (Stegomyia) aegypti is considered the main vector of the dengue, chikungunya, and Zika arbovirus transmission. Recent epidemiological studies in southern Brazil have shown an increase in the incidence of dengue, raising concerns over epidemiological control, monitoring, [...] Read more.

In Brazil, the mosquito Aedes (Stegomyia) aegypti is considered the main vector of the dengue, chikungunya, and Zika arbovirus transmission. Recent epidemiological studies in southern Brazil have shown an increase in the incidence of dengue, raising concerns over epidemiological control, monitoring, and surveys. Therefore, this study aimed at performing a historical spatiotemporal analysis of the Ae. aegypti house indices (HI) in southern Brazil over the last 19 years. As vector infestation was associated with climatic and environmental variables, HI data from the Brazilian Ministry of Health, climate data from the Giovanni web-based application, and environmental data from the Mapbiomas project were used in this study. Our results showed an expressive increase in the number of HI surveys in the municipalities confirming the vector presence, as compared to those in 2017. Environmental variables, such as urban infrastructure, precipitation, temperature, and humidity, were positively correlated with the Ae. aegypti HI. This was the first study to analyze Ae. aegypti HI surveys in municipalities of southern Brazil, and our findings could help in developing and planning disease control strategies to improve public health. Full article

(This article belongs to the Special Issue Emerging Vector-Borne Diseases and Public Health Challenges)

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9 pages, 379 KiB

Open AccessArticle

Chagas Disease: Seroprevalence and Associated Factors in Indigenous Communities of the Southern Limit of Argentine Chaco

by Carlina Colussi, Marcelo Nepote, Romina Chiaraviglio and Diego Mendicino

Trop. Med. Infect. Dis. 2023, 8(1), 64; https://doi.org/10.3390/tropicalmed8010064 - 14 Jan 2023

Cited by 1 | Viewed by 2573

Abstract

Chagas disease is more prevalent in socially vulnerable communities in the Gran Chaco Eco-region. The study evaluated the seroprevalence of Chagas disease and associated factors between May 2014 and September 2015, in indigenous communities of Santa Fe, Argentina, in the southern Chaco. Lysate [...] Read more.

Chagas disease is more prevalent in socially vulnerable communities in the Gran Chaco Eco-region. The study evaluated the seroprevalence of Chagas disease and associated factors between May 2014 and September 2015, in indigenous communities of Santa Fe, Argentina, in the southern Chaco. Lysate ELISA and indirect hemagglutination tests were used to detect antibodies against Trypanosoma cruzi, and recombinant ELISA was used in the case of disagreement. Household surveys were conducted with the head of household about risk factors for the disease. Serological tests were conducted on 298 people from three indigenous communities, 127 male and 171 female. Seroprevalence was 18.5%. A total of 64 surveys were conducted; 82.8% of the heads of household were male, with a median age of 39 years, and 61.0% had not completed primary school. In 35.9% of the households, there was at least one member of the cohabiting group infected with T. cruzi. The level of education of the head of household showed a statistically significant association with Chagas disease (OR = 3.43), among all the risk factors studied. The prevalence of infection is lower than that of other indigenous communities of the Gran Chaco, probably because environmental conditions are moderating and disfavoring the establishment of the insect vector in homes, but also because of socioeconomic differences with the rest of the eco-region. Beyond this, serological controls are needed to prevent vertical transmission. Full article

(This article belongs to the Special Issue Emerging Vector-Borne Diseases and Public Health Challenges)

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14 pages, 1663 KiB

Open AccessArticle

Evaluation of Methods for Collecting Mosquitoes (Culicidae: Diptera) in Canopy and Ground Strata in the Brazilian Savanna

by Luis Filipe Mucci, Eduardo Sterllino Bergo, Juliana Telles de Deus, Simone Luchetta Reginato, Mariza Pereira and Vera Lucia Fonseca de Camargo-Neves

Trop. Med. Infect. Dis. 2022, 7(12), 446; https://doi.org/10.3390/tropicalmed7120446 - 19 Dec 2022

Cited by 3 | Viewed by 2168

Abstract

The hand-net is the standard method for capturing mosquitoes with sylvatic diurnal activity in disease outbreaks in Brazil. However, occupational risks and biases related to the collectors’ abilities and attractiveness are important limitations. In this study, we compared hand-nets with automatic traps (CDC) [...] Read more.

The hand-net is the standard method for capturing mosquitoes with sylvatic diurnal activity in disease outbreaks in Brazil. However, occupational risks and biases related to the collectors’ abilities and attractiveness are important limitations. In this study, we compared hand-nets with automatic traps (CDC) associated to CO₂ and BG-Lure^® in the Vassununga State Park, a Brazilian Savanna protection area. The collections carried out over 27 days on the ground and the forest canopy. A total of 1555 mosquitoes were obtained in 20 taxa. The diversity index ranged between 1.12 and 1.79 and the dominance index from 0.22 to 0.40. The dominant species on the ground was Aedes scapularis (46.0%), and in the canopy, Hg. janthinomys/capricornii (31.9%). Haemagogus leucocelaenus was rare (n = 2). The hand-net resulted in the greatest diversity and abundance of species in both strata, followed by the traps associated with CO₂. A low degree of similarity was observed between the hand-net on the ground compared to the other capture methods. The use of BG-Lure^® alone resulted in a low number of specimens. In conclusion, the hand-net is still the method of choice for collecting arbovirus vectors in the diurnal period, especially yellow fever vectors. Full article

(This article belongs to the Special Issue Emerging Vector-Borne Diseases and Public Health Challenges)

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17 pages, 3183 KiB

Open AccessEditor’s ChoiceArticle

Genetic Diversity, Haplotype Relationships, and kdr Mutation of Malaria Anopheles Vectors in the Most Plasmodium knowlesi-Endemic Area of Thailand

by Tanawat Chaiphongpachara, Sedthapong Laojun, Tanasak Changbunjong, Suchada Sumruayphol, Nantana Suwandittakul, Sakultip Chookaew and Yuppayong Atta

Trop. Med. Infect. Dis. 2022, 7(12), 412; https://doi.org/10.3390/tropicalmed7120412 - 1 Dec 2022

Cited by 4 | Viewed by 2553

Abstract

Plasmodium knowlesi, a malaria parasite that occurs naturally in long-tailed macaques, pig-tailed macaques, and banded leaf monkeys, is currently regarded as the fifth of the human malaria parasites. We aimed to investigate genetic diversity based on the cytochrome c oxidase subunit I ( [...] Read more.

Plasmodium knowlesi, a malaria parasite that occurs naturally in long-tailed macaques, pig-tailed macaques, and banded leaf monkeys, is currently regarded as the fifth of the human malaria parasites. We aimed to investigate genetic diversity based on the cytochrome c oxidase subunit I (COI) gene, detect Plasmodium parasites, and screen for the voltage-gated sodium channel (VGSC)-mutation-mediated knockdown resistance (kdr) of Anopheles mosquitoes in Ranong province, which is the most P. knowlesi-endemic area in Thailand. One hundred and fourteen Anopheles females belonging to eight species, including An. baimaii (21.05%), An. minimus s.s. (20.17%), An. epiroticus (19.30%), An. jamesii (19.30%), An. maculatus s.s. (13.16%), An. barbirostris A3 (5.26%), An. sawadwongporni (0.88%), and An. aconitus (0.88%), were caught in three geographical regions of Ranong province. None of the Anopheles mosquitoes sampled in this study were infected with Plasmodium parasites. Based on the sequence analysis of COI sequences, An. epiroticus had the highest level of nucleotide diversity (0.012), followed by An. minimus (0.011). In contrast, An. maculatus (0.002) had the lowest level of nucleotide diversity. The Fu’s Fs and Tajima’s D values of the Anopheles species in Ranong were all negative, except the Tajima’s D values of An. minimus (0.077). Screening of VGSC sequences showed no presence of the kdr mutation of Anopheles mosquitoes. Our results could be used to further select effective techniques for controlling Anopheles populations in Thailand’s most P. knowlesi-endemic area. Full article

(This article belongs to the Special Issue Emerging Vector-Borne Diseases and Public Health Challenges)

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20 pages, 5870 KiB

Open AccessArticle

First Evidence of Co-Circulation of Emerging Leishmania martiniquensis, Leishmania orientalis, and Crithidia sp. in Culicoides Biting Midges (Diptera: Ceratopogonidae), the Putative Vectors for Autochthonous Transmission in Southern Thailand

by Nopporn Songumpai, Chulaluk Promrangsee, Preudtipong Noopetch, Padet Siriyasatien and Kanok Preativatanyou

Trop. Med. Infect. Dis. 2022, 7(11), 379; https://doi.org/10.3390/tropicalmed7110379 - 15 Nov 2022

Cited by 22 | Viewed by 3554

Abstract

Since 1996, autochthonous cases of emerging leishmaniasis caused by Leishmania (Mundinia) martiniquensis and Leishmania (Mundinia) orientalis have been more frequently reported, especially in the northern and southern parts of Thailand. However, the accurate identification of their natural vectors and [...] Read more.

Since 1996, autochthonous cases of emerging leishmaniasis caused by Leishmania (Mundinia) martiniquensis and Leishmania (Mundinia) orientalis have been more frequently reported, especially in the northern and southern parts of Thailand. However, the accurate identification of their natural vectors and reservoirs remains unconfirmed. Previous studies have suggested that these emerging parasites might be transmitted by other non-phlebotomine vectors. Herein, we speculated that Culicoides biting midges might act as the competent vectors responsible for autochthonous leishmaniasis in southern Thailand. In this research, 187 non-engorged, parous and gravid Culicoides females and 47 blood-engorged ones were trapped from the residences of two recently diagnosed visceral leishmaniasis patients in Sadao District and the unaffected site in Rattaphum District, Songkhla Province, southern Thailand. Species diversity and abundance of biting midges varied among the trapping sites. Using ITS1-PCR and BLASTn analysis, L. martiniquensis was predominantly detected in several Culicoides species, including C. peregrinus, C. oxystoma, C. mahasarakhamense, and C. huffi from the vicinity of patients’ houses; and in C. fordae and C. fulvus from the unaffected site. L. orientalis was also co-circulated in C. peregrinus and C. oxystoma caught near the second patient’s house. Additionally, Crithidia sp. were also detected using SSU rRNA-PCR across Culicoides spp. Host blood meal analysis of eight different Culicoides species from the unaffected site also revealed that all trapped Culicoides had fed on cows and goats, indicating the possible role of these mammalian species as reservoir hosts. Essentially, this study is the first entomological investigation, revealing the co-circulation of emerging trypanosomatids among several species of Culicoides biting midges and strongly supporting the potential role of this insect group as the main vectors responsible for the epidemiology of autochthonous leishmaniasis in southern Thailand. Full article

(This article belongs to the Special Issue Emerging Vector-Borne Diseases and Public Health Challenges)

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11 pages, 1276 KiB

Open AccessCommunication

Identification of Novel Reassortant Shuni Virus Strain in Clinical Cases of Israeli Ruminants, 2020–2021

by Natalia Golender, Joseph Seffi Varsano, Tomer Nissimyan and Eitan Tiomkin

Trop. Med. Infect. Dis. 2022, 7(10), 297; https://doi.org/10.3390/tropicalmed7100297 - 13 Oct 2022

Cited by 3 | Viewed by 1685

Abstract

The Shuni virus (SHUV) causes an endemic viral infection in Israel and South Africa. It belongs to the Simbu serogroup within the order Bunyavirales, family Peribunyaviridae, genus Orthobunyavirus. Recently, it has been identified in aborted cases of domestic ruminants, young [...] Read more.

The Shuni virus (SHUV) causes an endemic viral infection in Israel and South Africa. It belongs to the Simbu serogroup within the order Bunyavirales, family Peribunyaviridae, genus Orthobunyavirus. Recently, it has been identified in aborted cases of domestic ruminants, young cattle and horses manifesting neural signs and acute death, symptomatic cows, and in carcasses of wild animals. Moreover, SHUV was isolated and identified in humans. In this study, we describe clinical cases of SHUV infection in Israeli domestic ruminants in 2020–2021, which represented clinical manifestations of simbuviral infection including abortions, a neural lethal case in a fattening calf, and an acute symptomatic case in a beef cow. In all cases, SHUV was confirmed by complete or partial viral genome sequencing. There is a significant difference of M and L segments of the novel strains compared with those of all known SHUV strains, while the S segments have more than 99% nucleotide (nt) identity with Israeli and African “Israeli-like” strains previously circulated in 2014–2019. This indicates a reassortment origin of the strain. At the same time, M and S segment nt sequences showed about 98–99% nt identity with some South African strains collected in 2016–2018. Nevertheless, the viral origin and the geographical place of the reassortment stayed unknown. Full article

(This article belongs to the Special Issue Emerging Vector-Borne Diseases and Public Health Challenges)

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14 pages, 4898 KiB

Open AccessEditor’s ChoiceArticle

Spatial and Temporal Distribution of Aedes aegypti and Aedes albopictus Oviposition on the Coast of Paraná, Brazil, a Recent Area of Dengue Virus Transmission

by Silvia Jaqueline Pereira de Souza, André de Camargo Guaraldo, Nildimar Alves Honório, Daniel Cardoso Portela Câmara, Natali Mary Sukow, Sarita Terezinha Machado, Claudia Nunes Duarte dos Santos and Magda Clara Vieira da Costa-Ribeiro

Trop. Med. Infect. Dis. 2022, 7(9), 246; https://doi.org/10.3390/tropicalmed7090246 - 14 Sep 2022

Cited by 7 | Viewed by 3425

Abstract

Aedes aegypti and Aedes albopictus are considered the most important vectors of arboviruses in the world. Aedes aegypti is the primary vector of dengue, urban yellow fever, chikungunya and zika in Brazil, and Ae. albopictus is considered a potential vector. Distribution patterns and [...] Read more.

Aedes aegypti and Aedes albopictus are considered the most important vectors of arboviruses in the world. Aedes aegypti is the primary vector of dengue, urban yellow fever, chikungunya and zika in Brazil, and Ae. albopictus is considered a potential vector. Distribution patterns and the influence of climatic variables on the oviposition of Ae. aegypti and Ae. albopictus were evaluated in Morretes, a tourist city in the coastal area of Paraná State, Brazil, which has recently been experiencing cases of dengue fever. Eggs were collected using ovitraps over a period of one year (September 2017 to September 2018) and reared from hatching until the emergence of the adults. Both Aedes species were found in anthropized areas with a high human density index. Findings suggest that the monthly average temperature (LRT = 16.65, p = 0.001) had significant positive influences on the oviposition of the Aedes species. Considering the wide distribution of DENV around the Paraná coast and the presence of Ae. albopictus alongside Ae. aegypti, studies on natural arbovirus infection patterns and seasonality are recommended in the region. Full article

(This article belongs to the Special Issue Emerging Vector-Borne Diseases and Public Health Challenges)

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15 pages, 2252 KiB

Open AccessEditor’s ChoiceArticle

Toward New Epidemiological Landscapes of Trypanosoma cruzi (Kinetoplastida, Trypanosomatidae) Transmission under Future Human-Modified Land Cover and Climatic Change in Mexico

by Constantino González-Salazar, Anny K. Meneses-Mosquera, Alejandra Aguirre-Peña, Karla Paola J. Fernández-Castel, Christopher R. Stephens, Alma Mendoza-Ponce, Julián A. Velasco, Oscar Calderón-Bustamante and Francisco Estrada

Trop. Med. Infect. Dis. 2022, 7(9), 221; https://doi.org/10.3390/tropicalmed7090221 - 2 Sep 2022

Cited by 3 | Viewed by 2823

Abstract

Chagas disease, caused by the protozoa Trypanosoma cruzi, is an important yet neglected disease that represents a severe public health problem in the Americas. Although the alteration of natural habitats and climate change can favor the establishment of new transmission cycles for [...] Read more.

Chagas disease, caused by the protozoa Trypanosoma cruzi, is an important yet neglected disease that represents a severe public health problem in the Americas. Although the alteration of natural habitats and climate change can favor the establishment of new transmission cycles for T. cruzi, the compound effect of human-modified landscapes and current climate change on the transmission dynamics of T. cruzi has until now received little attention. A better understanding of the relationship between these factors and T. cruzi presence is an important step towards finding ways to mitigate the future impact of this disease on human communities. Here, we assess how wild and domestic cycles of T. cruzi transmission are related to human-modified landscapes and climate conditions (LUCC-CC). Using a Bayesian datamining framework, we measured the correlations among the presence of T. cruzi transmission cycles (sylvatic, rural, and urban) and historical land use, land cover, and climate for the period 1985 to 2012. We then estimated the potential range changes of T. cruzi transmission cycles under future land-use and -cover change and climate change scenarios for 2050 and 2070 time-horizons, with respect to “green” (RCP 2.6), “business-as-usual” (RCP 4.5), and “worst-case” (RCP 8.5) scenarios, and four general circulation models. Our results show how sylvatic and domestic transmission cycles could have historically interacted through the potential exchange of wild triatomines (insect vectors of T. cruzi) and mammals carrying T. cruzi, due to the proximity of human settlements (urban and rural) to natural habitats. However, T. cruzi transmission cycles in recent times (i.e., 2011) have undergone a domiciliation process where several triatomines have colonized and adapted to human dwellings and domestic species (e.g., dogs and cats) that can be the main blood sources for these triatomines. Accordingly, Chagas disease could become an emerging health problem in urban areas. Projecting potential future range shifts of T. cruzi transmission cycles under LUCC-CC scenarios we found for RCP 2.6 no expansion of favourable conditions for the presence of T. cruzi transmission cycles. However, for RCP 4.5 and 8.5, a significant range expansion of T. cruzi could be expected. We conclude that if sustainable goals are reached by appropriate changes in socio-economic and development policies we can expect no increase in suitable habitats for T. cruzi transmission cycles. Full article

(This article belongs to the Special Issue Emerging Vector-Borne Diseases and Public Health Challenges)

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16 pages, 8770 KiB

Open AccessArticle

Dengue, Chikungunya, and Zika: Spatial and Temporal Distribution in Rio de Janeiro State, 2015–2019

by Paula Maria Pereira de Almeida, Aline Araújo Nobre, Daniel Cardoso Portela Câmara, Luciana Moura Martins Costa, Izabel Cristina dos Reis, Mário Sérgio Ribeiro, Cristina Maria Giordano Dias, Tania Ayllón and Nildimar Alves Honório

Trop. Med. Infect. Dis. 2022, 7(7), 141; https://doi.org/10.3390/tropicalmed7070141 - 20 Jul 2022

Cited by 2 | Viewed by 2253

Abstract

Simultaneous spatial circulation of urban arboviral diseases, such as dengue, chikungunya, and Zika, is a major challenge. In this ecological study of urban arboviruses performed from 2015 to 2019, we analyzed the spatial and temporal dynamics of these arboviruses in all 92 municipalities [...] Read more.

Simultaneous spatial circulation of urban arboviral diseases, such as dengue, chikungunya, and Zika, is a major challenge. In this ecological study of urban arboviruses performed from 2015 to 2019, we analyzed the spatial and temporal dynamics of these arboviruses in all 92 municipalities and nine health regions of Rio de Janeiro state. Annual cumulative incidences are presented for all three arboviruses throughout the study period. Spatial analyses of the three studied arboviruses showed distinct behaviors among municipalities and health regions. Co-circulation of the three arboviruses in the state and a heterogeneous spatiotemporal pattern was observed for each disease and region, with dengue having a higher annual incidence during the five years of the study, as well as two consecutive epidemic years in the state. The increase in transmission in different regions of the state in one year culminated in an epidemic in the state in the following year. A high annual cumulative incidence of chikungunya occurred in municipalities from 2017 to 2019 and of Zika only in 2016. Some municipalities with higher population densities showed higher incidences for some arboviruses and appeared to contribute to the dissemination to cities of lower demographic density and maintenance of these urban arboviruses. Thus, regions recording increased incidences of the three diseases in their territories for long periods should be considered municipal poles, as they initiated and sustained high transmission within their region. Full article

(This article belongs to the Special Issue Emerging Vector-Borne Diseases and Public Health Challenges)

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18 pages, 1679 KiB

Open AccessArticle

Entomological Surveillance of Aedes Mosquitoes: Comparison of Different Collection Methods in an Endemic Area in RIO de Janeiro, Brazil

by Daniel Cardoso Portela Câmara, Claudia Torres Codeço, Tania Ayllón, Aline Araújo Nobre, Renata Campos Azevedo, Davis Fernandes Ferreira, Célio da Silva Pinel, Gláucio Pereira Rocha and Nildimar Alves Honório

Trop. Med. Infect. Dis. 2022, 7(7), 114; https://doi.org/10.3390/tropicalmed7070114 - 22 Jun 2022

Cited by 6 | Viewed by 3049

Abstract

Using collection methods for Aedes adults as surveillance tools provides reliable indices and arbovirus detection possibilities. This study compared the effectiveness of different methods for collecting Ae. aegypti and Ae. albopictus and detecting arboviruses circulating in field-caught female specimens. Collection sites were defined [...] Read more.

Using collection methods for Aedes adults as surveillance tools provides reliable indices and arbovirus detection possibilities. This study compared the effectiveness of different methods for collecting Ae. aegypti and Ae. albopictus and detecting arboviruses circulating in field-caught female specimens. Collection sites were defined in urban, peri-urban, and rural landscapes in two Brazilian cities. Collections were performed using Adultraps (ADT), BG-Sentinel (BGS), CDC-like traps (CDC), and indoor (ASP-I) and outdoor (ASP-O) aspiration during the rainy and dry seasons of 2015 and 2016. Generalized linear mixed models were used to model the effectiveness of each collection method. A total of 434 Ae. aegypti and 393 Ae. albopictus were collected. In total, 64 Ae. aegypti and sixteen Ae. albopictus female pools were tested for DENV, CHIKV, ZIKV, or YFV; none were positive. Positivity and density were linear at low densities (<1 specimen); thereafter, the relationship became non-linear. For Ae. aegypti, ADT and CDC were less effective, and ASP-I and ASP-O were as effective as BGS. For Ae. albopictus, all collection methods were less effective than BGS. This study highlights the need for an integrated surveillance method as an effective tool for monitoring Aedes vectors. Full article

(This article belongs to the Special Issue Emerging Vector-Borne Diseases and Public Health Challenges)

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13 pages, 852 KiB

Open AccessArticle

Needs Assessment of Southeastern United States Vector Control Agencies: Capacity Improvement Is Greatly Needed to Prevent the Next Vector-Borne Disease Outbreak

by Kyndall C. Dye-Braumuller, Jennifer R. Gordon, Danielle Johnson, Josie Morrissey, Kaci McCoy, Rhoel R. Dinglasan and Melissa S. Nolan

Trop. Med. Infect. Dis. 2022, 7(5), 73; https://doi.org/10.3390/tropicalmed7050073 - 13 May 2022

Cited by 10 | Viewed by 3130

Abstract

A national 2017 vector control capacity survey was conducted to assess the United States’ (U.S.’s) ability to prevent emerging vector-borne disease. Since that survey, the southeastern U.S. has experienced continued autochthonous exotic vector-borne disease transmission and establishment of invasive vector species. To understand [...] Read more.

A national 2017 vector control capacity survey was conducted to assess the United States’ (U.S.’s) ability to prevent emerging vector-borne disease. Since that survey, the southeastern U.S. has experienced continued autochthonous exotic vector-borne disease transmission and establishment of invasive vector species. To understand the current gaps in control programs and establish a baseline to evaluate future vector control efforts for this vulnerable region, a focused needs assessment survey was conducted in early 2020. The southeastern U.S. region was targeted, as this region has a high probability of novel vector-borne disease introduction. Paper copies delivered in handwritten envelopes and electronic copies of the survey were delivered to 386 unique contacts, and 150 returned surveys were received, corresponding to a 39% response rate. Overall, the survey found vector control programs serving areas with over 100,000 residents and those affiliated with public health departments had more core capabilities compared to smaller programs and those not affiliated with public health departments. Furthermore, the majority of vector control programs in this region do not routinely monitor for pesticide resistance. Taken as a whole, these results suggest that the majority of the southeastern U.S. is vulnerable to vector-borne disease outbreaks. Results from this survey raise attention to the critical need of providing increased resources to bring all vector control programs to a competent level, ensuring that public health is protected from the threat of vector-borne disease. Full article

(This article belongs to the Special Issue Emerging Vector-Borne Diseases and Public Health Challenges)

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Review

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13 pages, 1677 KiB

Open AccessReview

The Ongoing Epidemic of West Nile Virus in Greece: The Contribution of Biological Vectors and Reservoirs and the Importance of Climate and Socioeconomic Factors Revisited

by Dimitrios Kouroupis, Konstantina Charisi and Athina Pyrpasopoulou

Trop. Med. Infect. Dis. 2023, 8(9), 453; https://doi.org/10.3390/tropicalmed8090453 - 19 Sep 2023

Cited by 1 | Viewed by 2215

Abstract

Emerging infectious diseases have inflicted a significant health and socioeconomic burden upon the global population and governments worldwide. West Nile virus, a zoonotic, mosquito-borne flavivirus, was originally isolated in 1937 from a febrile patient in the West Nile Province of Uganda. It remained [...] Read more.

Emerging infectious diseases have inflicted a significant health and socioeconomic burden upon the global population and governments worldwide. West Nile virus, a zoonotic, mosquito-borne flavivirus, was originally isolated in 1937 from a febrile patient in the West Nile Province of Uganda. It remained confined mainly to Africa, the Middle East, and parts of Europe and Australia until 1999, circulating in an enzootic mosquito-bird transmission cycle. Since the beginning of the 21st century, a new, neurotropic, more virulent strain was isolated from human outbreaks initially occurring in North America and later expanding to South and South-eastern Europe. Since 2010, when the first epidemic was recorded in Greece, annual incidence has fluctuated significantly. A variety of environmental, biological and socioeconomic factors have been globally addressed as potential regulators of the anticipated intensity of the annual incidence rate; circulation within the zoonotic reservoirs, recruitment and adaptation of new potent arthropod vectors, average winter and summer temperatures, precipitation during the early summer months, and socioeconomic factors, such as the emergence and progression of urbanization and the development of densely populated areas in association with insufficient health policy measures. This paper presents a review of the biological and socioenvironmental factors influencing the dynamics of the epidemics of West Nile virus (WNV) cases in Greece, one of the highest-ranked European countries in terms of annual incidence. To date, WNV remains an unpredictable opponent as is also the case with other emerging infectious diseases, forcing the National Health systems to develop response strategies, control the number of infections, and shorten the duration of the epidemics, thus minimizing the impact on human and material resources. Full article

(This article belongs to the Special Issue Emerging Vector-Borne Diseases and Public Health Challenges)

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14 pages, 1716 KiB

Open AccessReview

Tick Control in a Connected World: Challenges, Solutions, and Public Policy from a United States Border Perspective

by Hannah S. Tiffin, Edwin G. Rajotte, Joyce M. Sakamoto and Erika T. Machtinger

Trop. Med. Infect. Dis. 2022, 7(11), 388; https://doi.org/10.3390/tropicalmed7110388 - 20 Nov 2022

Cited by 14 | Viewed by 5172

Abstract

Ticks are able to transmit the highest number of pathogen species of any blood-feeding arthropod and represent a growing threat to public health and agricultural systems worldwide. While there are numerous and varied causes and effects of changes to tick-borne disease (re)emergence, three [...] Read more.

Ticks are able to transmit the highest number of pathogen species of any blood-feeding arthropod and represent a growing threat to public health and agricultural systems worldwide. While there are numerous and varied causes and effects of changes to tick-borne disease (re)emergence, three primary challenges to tick control were identified in this review from a U.S. borders perspective. (1) Climate change is implicated in current and future alterations to geographic ranges and population densities of tick species, pathogens they can transmit, and their host and reservoir species, as highlighted by Ixodes scapularis and its expansion across southern Canada. (2) Modern technological advances have created an increasingly interconnected world, contributing to an increase in invasive tick species introductions through the increased speed and frequency of trade and travel. The introduction of the invasive Haemaphysalis longicornis in the eastern U.S. exemplifies the challenges with control in a highly interconnected world. (3) Lastly, while not a new challenge, differences in disease surveillance, control, and management strategies in bordering countries remains a critical challenge in managing ticks and tick-borne diseases. International inter-agency collaborations along the U.S.–Mexico border have been critical in control and mitigation of cattle fever ticks (Rhipicephalus spp.) and highlight the need for continued collaboration and research into integrated tick management strategies. These case studies were used to identify challenges and opportunities for tick control and mitigation efforts through a One Health framework. Full article

(This article belongs to the Special Issue Emerging Vector-Borne Diseases and Public Health Challenges)

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12 pages, 297 KiB

Open AccessReview

Narrative Review of the Control and Prevention of Knowlesi Malaria

by Ahmad Hazim Mohammad, Nurul Athirah Naserrudin, Syed Sharizman Syed Abdul Rahim, Jenarun Jelip, Azman Atil, Mohd Fazeli Sazali, Adora J. Muyou, Priya Dharishini Kunasagran, Nornazirah Ahmad Kamarudin, Zahir Izuan Azhar, Rahmat Dapari, Mohammad Saffree Jeffree and Mohd Rohaizat Hassan

Trop. Med. Infect. Dis. 2022, 7(8), 178; https://doi.org/10.3390/tropicalmed7080178 - 11 Aug 2022

Cited by 5 | Viewed by 2486

Abstract

Despite the reduction in the number of cases of human malaria throughout the world, the incidence rate of knowlesi malaria is continuing to rise, especially in Southeast Asia. The conventional strategies for the prevention and control of human malaria can provide some protection [...] Read more.

Despite the reduction in the number of cases of human malaria throughout the world, the incidence rate of knowlesi malaria is continuing to rise, especially in Southeast Asia. The conventional strategies for the prevention and control of human malaria can provide some protection against knowlesi malaria. Despite the numerous studies on the risk factors and the innovative methods that may be used to prevent and control the vectors of Plasmodium knowlesi, the incidence rate remains high. An integrated approach that includes environmental intervention should be adopted in order to ensure the successful control of zoonotic malaria. A combination of personal-level protection, vector control and environmental control may mitigate the risk of Plasmodium knowlesi transmission from macaques to humans and, ultimately, reduce the incidence rate of knowlesi malaria. Full article

(This article belongs to the Special Issue Emerging Vector-Borne Diseases and Public Health Challenges)

Other

Jump to: Research, Review

17 pages, 1085 KiB

Open AccessSystematic Review

Nucleic Acid Prevalence of Zoonotic Babesia in Humans, Animals and Questing Ticks, a Systematic Review and Meta-Analysis

by Xiao-Yan Yao, Shao-Qi Yu, Na Tian, Fei Wang, Shi-Zhu Li and Lan-Hua Li

Trop. Med. Infect. Dis. 2023, 8(3), 132; https://doi.org/10.3390/tropicalmed8030132 - 22 Feb 2023

Cited by 2 | Viewed by 1922

Abstract

Background: Zoonotic Babesia infections are an emerging public health threat globally. The geographical distribution, animal reservoirs and tick vectors vary greatly across Babesia species, and estimations of prevalence reported in works within the literature are also quite different. Better prevalence estimates and identification [...] Read more.

Background: Zoonotic Babesia infections are an emerging public health threat globally. The geographical distribution, animal reservoirs and tick vectors vary greatly across Babesia species, and estimations of prevalence reported in works within the literature are also quite different. Better prevalence estimates and identification of moderators are needed to understand the global transmission risk of different zoonotic Babesia species, and to provide crucial background information for the diagnosis, treatment and control of zoonotic babesiosis. Methods: We conducted a systematic review and meta-analysis to determine the global nucleic acid prevalence of different zoonotic Babesia species in humans, animals and ticks. Relevant publications were obtained from several electronic databases and grey literature up to December 2021. Articles were included if they were published in English or Chinese and reported the nucleic acid prevalence of zoonotic Babesia species in humans, animals or ticks. The pooled estimates of prevalence were determined using a random effect model. Heterogeneity was investigated using subgroup analyses and random effect meta-regression models. Results: Of 3205 unique studies, 28 were included by the systematic review of zoonotic Babesia for humans, 79 for animals and 104 for ticks. The results showed overall pooled estimates of nucleic acid prevalence for the following: B. microti—1.93% (0.32–4.69%) in humans; B. microti—7.80% (5.25–10.77%), B. divergens—2.12% (0.73–4.08%) and B. venatorum—1.42% (0.30–3.16%) in animals; and B. microti—2.30% (1.59–3.13%), B. divergens—0.16% (0.05–0.32%), and B. venatorum—0.39% (0.26–0.54%) in questing ticks. The type of population, animal reservoir or tick vector, detecting method and continent were moderators possibly associated with heterogeneity, yet the remaining heterogeneity that was not explained was still substantial (all QE p values < 0.05). Conclusions:B. microti is the most prevalent and widely distributed zoonotic Babesia species globally. The wide range of suitable animal reservoirs and potential transmission vectors and high prevalence in animals and ticks may contribute to the worldwide distribution of B. microti. Other zoonotic Babesia species were relatively less prevalent and were reported in quite limited areas. Full article

(This article belongs to the Special Issue Emerging Vector-Borne Diseases and Public Health Challenges)

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6 pages, 550 KiB

Open AccessCase Report

First Human Usutu Virus Reported in Asti (Piedmont, Italy, August 2022) and Early Follow-Up

by Tommaso Lupia, Fabio Paolo Marletto, Ilvana Tiziana Scuvera, Roberta Bosio, Barbara Rizzello, Valentina Fornari, Daniela Maria Luisa Vivenza, Valeria Ghisetti, Maria Teresa Brusa, Silvia Corcione and Francesco Giuseppe De Rosa

Trop. Med. Infect. Dis. 2022, 7(12), 443; https://doi.org/10.3390/tropicalmed7120443 - 17 Dec 2022

Cited by 2 | Viewed by 1500

Abstract

The Usutu virus (USUV) has recently attracted the attention of scientists because of its rapid spread across Europe and its growth over the previous seasons in Italy. Here, we describe the first case of USUV infection in Asti, Piedmont region, Italy. The patient [...] Read more.

The Usutu virus (USUV) has recently attracted the attention of scientists because of its rapid spread across Europe and its growth over the previous seasons in Italy. Here, we describe the first case of USUV infection in Asti, Piedmont region, Italy. The patient remained asymptomatic in the acute phase and during the early follow-up, despite a mild increase in liver enzymes. The prompt diagnosis in this patient was due to positive qualitative PCR for WNV blood-donor screening with negative RT-PCR of WNV and positive USUV-RNA following the confirmation test. Blood-donor screening and transmission risk monitoring are pivotal in following the spread of this Flavivirus in non-endemic countries, due to the high percentage of asymptomatic carriers. Full article

(This article belongs to the Special Issue Emerging Vector-Borne Diseases and Public Health Challenges)

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