bims-mosdis Biomed News
on Mosquito distribution and disease
Issue of 2023‒04‒16
fifteen papers selected by
Richard Halfpenny, Staffordshire University
  1. Breeding site selection and co-existing patterns of tropical mosquitoes.
  2. Distribution of Invasive Aedes Mosquitoes in West-Central Illinois, 2014-18: Record Updates for Aedes japonicus and Ae. albopictus.
  3. Arbovirus surveillance on the Mexico-USA border: West Nile virus identification in various species of field mosquitoes.
  4. Dengue and chikungunya virus loads in the mosquito Aedes aegypti are determined by distinct genetic architectures.
  5. Validity of Self-Reported Mosquito Bites to Assess Household Mosquito Abundance in Six Communities of Esmeraldas Province, Ecuador.
  6. The relative importance of key meteorological factors affecting numbers of mosquito vectors of dengue fever.
  7. Characterizing the Wolbachia infection in field-collected Culicidae mosquitoes from Hainan Province, China.
  8. High vector diversity and malaria transmission dynamics in five sentinel sites in Cameroon.
  9. Evolutionary dynamics of Usutu virus: Worldwide dispersal patterns and transmission dynamics in Europe.
  10. Coinfection and circulation of chikungunya virus and dengue virus in pediatric patients in Myanmar, 2019.
  11. Mosquito-borne viruses causing human disease in Fennoscandia-Past, current, and future perspectives.
  12. Three new species of Culex (Melanoconion) (Diptera: Culicidae) from French Guiana based on morphological and molecular data.
  13. How can the complex epidemiology of malaria in India impact its elimination?
  14. Dengue outbreak update in India: 2022.
  15. Spatiotemporal dynamics and recurrence of chikungunya virus in Brazil: an epidemiological study.
  1. Med Vet Entomol. 2023 Apr 15.
    Breeding site selection and co-existing patterns of tropical mosquitoes.
    W G D Chathuranga, T C Weeraratne, S P Abeysundara, S H P P Karunaratne, W A Priyanka P de Silva.
      We investigated the physicochemical properties and the biotic interactions of breeding sites of tropical mosquito species. Field sampling was done in 12 study areas in Sri Lanka covering areas with secondary natural forests and human settlements. A total of 226 breeding sites were investigated to determine the biotic interactions and physiochemical properties of breeding water (pH, Conductivity, Dissolved Oxygen, Total Dissolved Solids and Temperature). A total of 80.5% of breeding sites from both habitats were positive for mosquito larvae of seven genera and 24 species. Orthopodomyia flavithorax (297) and Aedes albopictus (295) were dominated in tree holes of Alstonia macrophylla, Vateria copallifera and Artocarpus nobilis. Diversity indices showed that the diversity of mosquitoes is high in wet zone habitats of Sri Lanka compared to dry and intermediate zone habitats. Aedes albopictus coexisted with 11 different mosquito species while it avoided larvae of Culex fuscanus, Cx. uniformis and Tripteroides affinis. Strong positive associations were reported between Ae. albopictus and Ar. subalbatus while larvae of Or. flavithorax mosquitoes were not co-occurred with the larvae of Ae. vittatus, Ae. aegypti, Cx. sitiens, Ar. subalbatus, Anopheles spp and Tr. affinis. The findings identified the breeding adaptability and tolerance to a wide range of physiochemical properties of tropical mosquito communities.
    Keywords:  breeding site selection; mosquito larvae; ornithophilic mosquitoes; physicochemical characteristics; sympatric species; vector control
    DOI:  https://doi.org/10.1111/mve.12656
  2. J Am Mosq Control Assoc. 2023 Mar 01. 39(1): 1-11
    Distribution of Invasive Aedes Mosquitoes in West-Central Illinois, 2014-18: Record Updates for Aedes japonicus and Ae. albopictus.
    Jason R Hunt, Michele M Rehbein, Roger C Viadero, Catherine L Miller.
      A comprehensive surveillance of Aedes mosquitoes in west-central Illinois has not been conducted in recent years, resulting in incomplete distribution records for several Illinois counties. As of 2014, out of 102 Illinois counties, active populations of Ae. japonicus had been confirmed in 15 counties, and Ae. albopictus confirmed in 34 counties. The Miller laboratory at Western Illinois University (WIU) began the WIU Vector Biology Initiative (WIU-VBI) in 2014 to address the lack of mosquito surveillance in west-central Illinois. Through this effort, the presence of Ae. japonicus was confirmed for the 1st time in Fulton, Hancock, and Schuyler counties, IL, from 2014 to 2018. Actively breeding populations were confirmed in Cass, Fulton, McDonough, and Schuyler counties, IL. Additionally, Ae. albopictus was observed for the 1st time in Cass, Fulton, Hancock, McDonough, and Schuyler counties, IL, in 2016 and 2017, with active breeding populations in Cass and McDonough counties, IL.
    Keywords:   Hulecoeteomyia japonica ; Stegomyia albopicta ; Illinois
    DOI:  https://doi.org/10.2987/22-7105
  3. Trop Med Int Health. 2023 Apr 12.
    Arbovirus surveillance on the Mexico-USA border: West Nile virus identification in various species of field mosquitoes.
    David Mejia Zuñiga, Jorge Cime-Castillo, Laura Moncada Hernandez, Francisco Flores Mendoza, Janeth Tapia Bueno, Ángel Reyes Moya, Julia Rodríguez Aguirre, Juan Andrew Avitia, Cassandra González-Acosta, Fabian Correa-Morales, Vargas Valeria, Humberto Lanz-Mendoza.
      West Nile virus (WNV) has been documented in human and/or mosquito samples near the border with Mexico in El Paso, Texas, and Doña Ana County, New Mexico. However, on the Mexican side of the border, particularly in the State of Chihuahua, no such cases of WNV-infected mosquitoes have been documented. We tested 367 mosquitoes of four species (Culex quinquefasciatus, Cx. tarsalis, Aedes aegypti, and Aedes (Ochlerotatus) epactius) and found a high rate of WNV-positivity, including the first record of Ae. (Ochlerotatus) epactius infection with WNV. These results call for intensifying WNV surveillance efforts on the border between the United States and Mexico, with particular emphasis on vector control and monitoring of the species included in this study.
    Keywords:  Aedes (Ochlerotatus) epactius; West Nile virus; flavivirus; mosquito; vector-borne-disease
    DOI:  https://doi.org/10.1111/tmi.13874
  4. PLoS Pathog. 2023 Apr 12. 19(4): e1011307
    Dengue and chikungunya virus loads in the mosquito Aedes aegypti are determined by distinct genetic architectures.
    Mario Novelo, Heverton Lc Dutra, Hillery C Metz, Matthew J Jones, Leah T Sigle, Francesca D Frentiu, Scott L Allen, Stephen F Chenoweth, Elizabeth A McGraw.
      Aedes aegypti is the primary vector of the arboviruses dengue (DENV) and chikungunya (CHIKV). These viruses exhibit key differences in their vector interactions, the latter moving more quicky through the mosquito and triggering fewer standard antiviral pathways. As the global footprint of CHIKV continues to expand, we seek to better understand the mosquito's natural response to CHIKV-both to compare it to DENV:vector coevolutionary history and to identify potential targets in the mosquito for genetic modification. We used a modified full-sibling design to estimate the contribution of mosquito genetic variation to viral loads of both DENV and CHIKV. Heritabilities were significant, but higher for DENV (40%) than CHIKV (18%). Interestingly, there was no genetic correlation between DENV and CHIKV loads between siblings. These data suggest Ae. aegypti mosquitoes respond to the two viruses using distinct genetic mechanisms. We also examined genome-wide patterns of gene expression between High and Low CHIKV families representing the phenotypic extremes of viral load. Using RNAseq, we identified only two loci that consistently differentiated High and Low families: a long non-coding RNA that has been identified in mosquito screens post-infection and a distant member of a family of Salivary Gland Specific (SGS) genes. Interestingly, the latter gene is also associated with horizontal gene transfer between mosquitoes and the endosymbiotic bacterium Wolbachia. This work is the first to link the SGS gene to a mosquito phenotype. Understanding the molecular details of how this gene contributes to viral control in mosquitoes may, therefore, also shed light on its role in Wolbachia.
    DOI:  https://doi.org/10.1371/journal.ppat.1011307
  5. Am J Trop Med Hyg. 2023 Apr 10. pii: tpmd220371. [Epub ahead of print]
    Validity of Self-Reported Mosquito Bites to Assess Household Mosquito Abundance in Six Communities of Esmeraldas Province, Ecuador.
    Brian Glover, Gwenyth O Lee, Oscar Suing, Thien-An Ha, Panpim Thongsripong, Varsovia Cevallos, Patricio Ponce, Hannah Van Wyk, Amy C Morrison, Josefina Coloma, Joseph N S Eisenberg.
      Mosquito-borne diseases are a global burden; however, current methods of evaluating human-mosquito contact rates are expensive and time consuming. Validated surveys of self-reported mosquito bites may be an inexpensive way to determine mosquito presence and bite exposure level in an area, but this remains untested. In this study, a survey of self-reported mosquito bites was validated against household mosquito abundance from six communities in Esmeraldas, Ecuador. From February 2021 to July 2022, households were interviewed monthly, and five questions were used to ask participants how often they were bitten by mosquitoes at different times during the day. At the same time, adult mosquitoes were collected using a Prokopack aspirator. Species were identified and counted. Survey responses were compared with the total number of mosquitoes found in the home using negative binomial regression. More frequent self-reported mosquito bites were significantly associated with higher numbers of collected adult mosquitoes. These associations were driven by the prevalence of the dominant genera, Culex. These results suggest that surveys of perceived mosquito bites relate to actual mosquito presence, making them a potentially useful tool for determining the impact of vector-control interventions on community perceptions of risk but less useful for assessing the risk of nondominant species such as Aedes aegypti. Further work is needed to examine the robustness of these results in other contexts.
    DOI:  https://doi.org/10.4269/ajtmh.22-0371
  6. PLoS Negl Trop Dis. 2023 Apr 13. 17(4): e0011247
    The relative importance of key meteorological factors affecting numbers of mosquito vectors of dengue fever.
    Yan Liu, Xia Wang, Sanyi Tang, Robert A Cheke.
      Although single factors such as rainfall are known to affect the population dynamics of Aedes albopictus, the main vector of dengue fever in Eurasia, the synergistic effects of different meteorological factors are not fully understood. To address this topic, we used meteorological data and mosquito-vector association data including Breteau and ovitrap indices in key areas of dengue outbreaks in Guangdong Province, China, to formulate a five-stage mathematical model for Aedes albopictus population dynamics by integrating multiple meteorological factors. Unknown parameters were estimated using a genetic algorithm, and the results were analyzed by k-Shape clustering, random forest and grey correlation analysis. In addition, the population density of mosquitoes in 2022 was predicted and used for evaluating the effectiveness of the model. We found that there is spatiotemporal heterogeneity in the effects of temperature and rainfall and their distribution characteristics on the diapause period, the numbers of peaks in mosquito densities in summer and the annual total numbers of adult mosquitoes. Moreover, we identified the key meteorological indicators of the mosquito quantity at each stage and that rainfall (seasonal rainfall and annual total rainfall) was more important than the temperature distribution (seasonal average temperature and temperature index) and the uniformity of rainfall annual distribution (coefficient of variation) for most of the areas studied. The peak rainfall during the summer is the best indicator of mosquito population development. The results provide important theoretical support for the future design of mosquito vector control strategies and early warnings of mosquito-borne diseases.
    DOI:  https://doi.org/10.1371/journal.pntd.0011247
  7. Parasit Vectors. 2023 Apr 14. 16(1): 128
    Characterizing the Wolbachia infection in field-collected Culicidae mosquitoes from Hainan Province, China.
    Yiji Li, Yingbo Sun, Jiaquan Zou, Daibin Zhong, Rui Liu, Chuanlong Zhu, Wenting Li, Yanhe Zhou, Liwang Cui, Guofa Zhou, Gang Lu, Tingting Li.
      BACKGROUND: Mosquitoes are vectors of many pathogens, such as malaria, dengue virus, yellow fever virus, filaria and Japanese encephalitis virus. Wolbachia are capable of inducing a wide range of reproductive abnormalities in their hosts, such as cytoplasmic incompatibility. Wolbachia has been proposed as a tool to modify mosquitoes that are resistant to pathogen infection as an alternative vector control strategy. This study aimed to determine natural Wolbachia infections in different mosquito species across Hainan Province, China.METHODS: Adult mosquitoes were collected using light traps, human landing catches and aspirators in five areas in Hainan Province from May 2020 to November 2021. Species were identified based on morphological characteristics, species-specific PCR and DNA barcoding of cox1 assays. Molecular classification of species and phylogenetic analyses of Wolbachia infections were conducted based on the sequences from PCR products of cox1, wsp, 16S rRNA and FtsZ gene segments.
    RESULTS: A total of 413 female adult mosquitoes representing 15 species were identified molecularly and analyzed. Four mosquito species (Aedes albopictus, Culex quinquefasciatus, Armigeres subalbatus and Culex gelidus) were positive for Wolbachia infection. The overall Wolbachia infection rate for all mosquitoes tested in this study was 36.1% but varied among species. Wolbachia types A, B and mixed infections of A × B were detected in Ae. albopictus mosquitoes. A total of five wsp haplotypes, six FtsZ haplotypes and six 16S rRNA haplotypes were detected from Wolbachia infections. Phylogenetic tree analysis of wsp sequences classified them into three groups (type A, B and C) of Wolbachia strains compared to two groups each for FtsZ and 16S rRNA sequences. A novel type C Wolbachia strain was detected in Cx. gelidus by both single locus wsp gene and the combination of three genes.
    CONCLUSION: Our study revealed the prevalence and distribution of Wolbachia in mosquitoes from Hainan Province, China. Knowledge of the prevalence and diversity of Wolbachia strains in local mosquito populations will provide part of the baseline information required for current and future Wolbachia-based vector control approaches to be conducted in Hainan Province.
    Keywords:  16S rRNA; FtsZ; Genetic diversity; Mosquito; Phylogeny; Species diversity; Wolbachia; Wsp
    DOI:  https://doi.org/10.1186/s13071-023-05719-y
  8. Malar J. 2023 Apr 13. 22(1): 123
    High vector diversity and malaria transmission dynamics in five sentinel sites in Cameroon.
    Etienne Fondjo, Jean-Claude Toto, Magellan Tchouakui, Wolfgang Ekoko Eyisap, Salomon Patchoke, Benjamin Menze, Boris Njeambosay, Francis Zeukeug, Raymond Tabue Ngomdjum, Elysée Mandeng, Emmanuel Elanga-Ndille, Edmond Kopya, Jerome Achille Binyang, Cyrille Ndo, Billy Tene-Fossog, Armel Tedjou, Elysée Nchoutpouen, Frederic Tchouine, Dorothy Achu, Kelley Ambrose, Judith Hedje, Celestin Kouambeng, Jenny Carlson, Sarah Zohdy, Joseph Chabi.
      BACKGROUND: Malaria remains one of the main causes of morbidity and mortality in Cameroon. To inform vector control intervention decision making, malaria vector surveillance was conducted monthly from October 2018 to September 2020 in five selected sentinel sites (Gounougou and Simatou in the North, and Bonabéri, Mangoum and Nyabessang in the South).METHODS: Human landing catches (HLCs), U.S. Centers for Disease Control and Prevention (CDC) light traps, and pyrethrum spray catches (PSCs) were used to assess vector density, species composition, human biting rate (HBR), endophagic index, indoor resting density (IRD), parity, sporozoite infection rates, entomological inoculation rate (EIR), and Anopheles vectorial capacity.
    RESULTS: A total of 139,322 Anopheles mosquitoes from 18 species (or 21 including identified sub-species) were collected across all sites. Out of the 18 species, 12 were malaria vectors including Anopheles gambiae sensu lato (s.l.), Anopheles funestus s.l.., Anopheles nili, Anopheles moucheti, Anopheles paludis, Anopheles demeilloni, Anopheles. pharoensis, Anopheles ziemanni, Anopheles multicinctus, Anopheles tenebrosus, Anopheles rufipes, and Anopheles marshallii. Anopheles gambiae s.l. remains the major malaria vector (71% of the total Anopheles) collected, though An. moucheti and An. paludis had the highest sporozoite rates in Nyabessang. The mean indoor HBR of Anopheles ranged from 11.0 bites/human/night (b/h/n) in Bonabéri to 104.0 b/h/n in Simatou, while outdoors, it varied from 24.2 b/h/n in Mangoum to 98.7 b/h/n in Simatou. Anopheles gambiae s.l. and An. moucheti were actively biting until at least 8:00 a.m. The mean Anopheles IRD was 17.1 females/room, and the parity rate was 68.9%. The mean EIRs for each site were 55.4 infective bites/human/month (ib/h/m) in Gounougou, 99.0 ib/h/m in Simatou, 51.2 ib/h/m in Mangoum, 24.4 ib/h/m in Nyabessang, and 18.1 ib/h/m in Bonabéri. Anopheles gambiae s.l. was confirmed as the main malaria vector with the highest vectorial capacity in all sites based on sporozoite rate, except in Nyabessang.
    CONCLUSION: These findings highlight the high malaria transmission occurring in Cameroon and will support the National Malaria Control Program to design evidence-based malaria vector control strategies, and deployment of effective and integrated vector control interventions to reduce malaria transmission and burden in Cameroon, where several Anopheles species could potentially maintain year-round transmission.
    Keywords:  Cameroon; Malaria transmission; Vector diversity; Vectorial capacity
    DOI:  https://doi.org/10.1186/s12936-023-04552-z
  9. Front Microbiol. 2023 ;14 1145981
    Evolutionary dynamics of Usutu virus: Worldwide dispersal patterns and transmission dynamics in Europe.
    Marina Siljic, Rastko Sehovic, Marko Jankovic, Gorana Stamenkovic, Ana Loncar, Marija Todorovic, Maja Stanojevic, Valentina Cirkovic.
      Background: Usutu virus (USUV) is an emerging mosquito-borne Flavivirus, with birds as the main zoonotic reservoir. Humans are accidental hosts and mostly develop mild or even asymptomatic infections, although severe complications such as encephalitis can also arise. Detailed characterization of the pathogen's phylogenetics may offer valuable insights into the prediction and prevention of potential epidemics; however, lack of uniformity and the number of available USUV sequences worldwide hamper comprehensive investigation.Aim: The study aimed to investigate USUV spatio-temporal dispersal inter- and intracontinentally and to estimate the dynamics of viral spread within Europe.
    Methods: Phylogeographic and phylodynamic analyses were done using advanced phylogenetic methods implemented in Beast 1.10.4 and Beast 2.6.4 software packages.
    Results: Herein, we report on a new USUV isolate from Culex pipiens collected in 2019 from Serbia. The results of this research revealed two newly described intercontinental migration events of USUV from Africa to Germany in the 1970s and from Africa to the Middle East (Israel) in the late 90s. Finally, phylodynamic analysis substantiated the ongoing active expansion of USUV in Europe.
    Conclusion: The data would imply a high potential for further USUV expansion in Europe. Detailed phylogenetic characterization of the pathogen may offer valuable insights into prediction and prevention of potential epidemics; however, lack of uniformity and number of available USUV sequences worldwide hampers comprehensive investigation. This study draws attention to the need for upscaling USUV surveillance.
    Keywords:  Usutu virus; emerging disease; evolutionary dynamic; mosquito vectors; phylodynamics; phylogeography
    DOI:  https://doi.org/10.3389/fmicb.2023.1145981
  10. Microbes Infect. 2023 Apr 06. pii: S1286-4579(23)00032-1. [Epub ahead of print] 105129
    Coinfection and circulation of chikungunya virus and dengue virus in pediatric patients in Myanmar, 2019.
    Mya Myat Ngwe Tun, Aung Kyaw Kyaw, Takeshi Nabeshima, Shyam Prakash Dumre, Aung Min Soe, Khine Mya Nwe, Su Su Myaing, Ei Phyu Lwin, Ye Thu Win, Shingo Inoue, Yuki Takamatsu, Takeshi Urano, Hlaing Myat Thu, Kyaw Zin Thant, Zaw Than Htun, Kouichi Morita.
      Myanmar is an endemic country for arboviruses, and outbreaks occur frequently. A cross-sectional analytical study was conducted during the peak season of the chikungunya virus (CHIKV) outbreak in 2019. A total of 201 patients with acute febrile illness who were admitted to the 550-bedded Mandalay Children Hospital in Myanmar were enrolled in the study, and virus isolation, serological tests, and molecular tests for the dengue virus (DENV) and CHIKV were performed for all samples. Out of 201 patients, 71 (35.3%) were only DENV-infected, 30 (14.9%) were only CHIKV-infected and 59 (29.4%) were coinfected with DENV and CHIKV. The viremia levels of the DENV- and CHIKV- mono-infected groups were significantly higher than those of the group coinfected with DENV and CHIKV. Genotype I of DENV-1, genotypes I and III of DENV-3, genotype I of DENV-4 and the East/Central/South African genotype of CHIKV were co-circulating during the study period. Two novel epistatic mutations of CHIKV (E1:K211E and E2:V264A) were noted. This study highlighted that there were many coinfection cases during the outbreak and that the co-circulation of both viruses in DENV-endemic regions warrants effective monitoring of these emerging pathogens via comprehensive surveillance to facilitate the implementation of effective control measures.
    Keywords:  2019; Chikungunya; Co-infection; Dengue; Myanmar; Viremia
    DOI:  https://doi.org/10.1016/j.micinf.2023.105129
  11. Front Med (Lausanne). 2023 ;10 1152070
    Mosquito-borne viruses causing human disease in Fennoscandia-Past, current, and future perspectives.
    Lukas Wilkman, Clas Ahlm, Magnus Evander, Olivia Wesula Lwande.
      Five different mosquito-borne viruses (moboviruses) significant to human disease are known to be endemic to Fennoscandia (Sindbis virus, Inkoo virus, Tahyna virus, Chatanga virus, and Batai virus). However, the incidence of mosquito-borne virus infections in Fennoscandia is unknown, largely due to underdiagnosing and lack of surveillance efforts. The Fennoscandian moboviruses are difficult to prevent due to their method of transmission, and often difficult to diagnose due to a lack of clear case definition criteria. Thus, many cases are likely to be mis-diagnosed, or even not diagnosed at all. Significant long-term effects, often in the form of malaise, rashes, and arthralgia have been found for some of these infections. Research into mobovirus disease is ongoing, though mainly focused on a few pathogens, with many others neglected. With moboviruses found as far north as the 69th parallel, studying mosquito-borne disease occurring in the tropics is only a small part of the whole picture. This review is written with the objective of summarizing current medically relevant knowledge of moboviruses occurring in Fennoscandia, while highlighting what is yet unknown and possibly overlooked.
    Keywords:  Fennoscandia; Sindbis virus; arbovirus; epidemiology; mobovirus; mosquito-borne virus
    DOI:  https://doi.org/10.3389/fmed.2023.1152070
  12. Zootaxa. 2022 Nov 07. 5205(2): 177-189
    Three new species of Culex (Melanoconion) (Diptera: Culicidae) from French Guiana based on morphological and molecular data.
    Stanislas Talaga, Mathilde Gendrin.
      Culex mosquitoes of the subgenus Melanoconion Theobald, 1903 of the genus Culex Linnaeus, 1758 include numerous species recognized as vectors of viruses affecting humans. This subgenus is the most speciose among the entire mosquito fauna of the Americas. Despite decades of taxonomic research, many species remain undiscovered, especially in the Amazonian biome. In this article, we provide the description of three new species of Culex (Melanoconion) recently discovered in a biological reserve in French Guiana. Culex (Mel.) sallumae n. sp., Cx. (Mel.) hutchingsae n. sp. and Cx. (Mel.) lucakermanni n. sp. are described based on both morphological features of the male genitalia and molecular barcodes obtained from type specimens. Diagnostic characters to assist their identification are provided and their placement within the infrasubgeneric classification of the subgenus Melanoconion is discussed.
    DOI:  https://doi.org/10.11646/zootaxa.5205.2.5
  13. Trends Parasitol. 2023 Apr 06. pii: S1471-4922(23)00067-3. [Epub ahead of print]
    How can the complex epidemiology of malaria in India impact its elimination?
    Nikhat Khan, Gauri Awasthi, Aparup Das.
      Malaria is a human health hazard in the tropical and subtropical zones of the globe and is poised to be eliminated by the year 2030. Despite a decrease in incidence in the past two decades, many endemic countries, including India, report cases regularly. The epidemiology of malaria in India is unique owing to several features of the Plasmodium parasites, Anopheles vectors, ecoepidemiological situations conducive to disease transmission, and susceptible humans living in rural and forested areas. Limitations in public health reach, and poor health-seeking behaviour of vulnerable populations living in hard-to-reach areas, add to the problem. We bring all of these factors together in a comprehensive framework and opine that, in spite of complexities, targeted elimination of malaria in India is achievable with planned programmatic approaches.
    Keywords:  Anopheles; India; Plasmodium; elimination; epidemiology; malaria
    DOI:  https://doi.org/10.1016/j.pt.2023.03.006
  14. Indian J Public Health. 2023 Jan-Mar;67(1):67(1): 181-183
    Dengue outbreak update in India: 2022.
    Nitin Singh, Amresh Kumar Singh, Ankur Kumar.
      Dengue is an emerging illness in India, where it is endemic in some areas and sometimes causes yearly epidemics. Each dengue outbreak starts with high death and morbidity, which has a significant socioeconomic impact. As of September 30, 2022, India had 63,280 dengue cases, according to information provided by the National Centre for Vector Borne Diseases Control. North India is most severely impacted by each outbreak. In Uttar Pradesh, the state with the most population in India, there have been 2060 confirmed cases of dengue and 1 mortality till September 2022 reported. Patients are being reported from semi-urban, rural, and urban areas. It is essential to properly monitor disease cases through disease surveillance in order to ensure prompt case management if dengue outbreak control is to be achieved. An efficient diagnostic approach for early diagnosis is urgently required to reduce the severity of the sickness, the length of the hospital stay, and clinical consequences.
    Keywords:  Dengue outbreak; Vector borne diseases; dengue diagnosis; dengue severity.
    DOI:  https://doi.org/10.4103/ijph.ijph_1517_22
  15. Lancet Microbe. 2023 Apr 06. pii: S2666-5247(23)00033-2. [Epub ahead of print]
    Spatiotemporal dynamics and recurrence of chikungunya virus in Brazil: an epidemiological study.
    William M de Souza, Shirlene T S de Lima, Leda M Simões Mello, Darlan S Candido, Lewis Buss, Charles Whittaker, Ingra M Claro, Nilani Chandradeva, Fabiana Granja, Ronaldo de Jesus, Poliana S Lemos, Daniel A Toledo-Teixeira, Priscilla P Barbosa, Antonio Carlos L Firmino, Mariene R Amorim, Larissa M F Duarte, Ivan B Pessoa, Julia Forato, Irihane L Vasconcelos, Ana Carolina B M Maximo, Emerson L L Araújo, Liana Perdigão Mello, Ester C Sabino, José Luiz Proença-Módena, Nuno R Faria, Scott C Weaver.
      BACKGROUND: Chikungunya virus (CHIKV) is an Aedes mosquito-borne virus that has caused large epidemics linked to acute, chronic, and severe clinical outcomes. Currently, Brazil has the highest number of chikungunya cases in the Americas. We aimed to investigate the spatiotemporal dynamics and recurrence pattern of chikungunya in Brazil since its introduction in 2013.METHODS: In this epidemiological study, we used CHIKV genomic sequencing data, CHIKV vector information, and aggregate clinical data on chikungunya cases from Brazil. The genomic data comprised 241 Brazilian CHIKV genome sequences from GenBank (n=180) and the 2022 CHIKV outbreak in Ceará state (n=61). The vector data (Breteau index and House index) were obtained from the Brazilian Ministry of Health for all 184 municipalities in Ceará state and 116 municipalities in Tocantins state in 2022. Epidemiological data on laboratory-confirmed cases of chikungunya between 2013 and 2022 were obtained from the Brazilian Ministry of Health and Laboratory of Public Health of Ceará. We assessed the spatiotemporal dynamics of chikungunya in Brazil via time series, mapping, age-sex distribution, cumulative case-fatality, linear correlation, logistic regression, and phylogenetic analyses.
    FINDINGS: Between March 3, 2013, and June 4, 2022, 253 545 laboratory-confirmed chikungunya cases were reported in 3316 (59·5%) of 5570 municipalities, mainly distributed in seven epidemic waves from 2016 to 2022. To date, Ceará in the northeast has been the most affected state, with 77 418 cases during the two largest epidemic waves in 2016 and 2017 and the third wave in 2022. From 2016 to 2022 in Ceará, the odds of being CHIKV-positive were higher in females than in males (odds ratio 0·87, 95% CI 0·85-0·89, p<0·0001), and the cumulative case-fatality ratio was 1·3 deaths per 1000 cases. Chikungunya recurrences in the states of Ceará, Tocantins (recurrence in 2022), and Pernambuco (recurrence in 2021) were limited to municipalities with few or no previously reported cases in the previous epidemic waves. The recurrence of chikungunya in Ceará in 2022 was associated with a new East-Central-South-African lineage. Population density metrics of the main CHIKV vector in Brazil, Aedes aegypti, were not correlated spatially with locations of chikungunya recurrence in Ceará and Tocantins.
    INTERPRETATION: Spatial heterogeneity of CHIKV spread and population immunity might explain the recurrence pattern of chikungunya in Brazil. These results can be used to inform public health interventions to prevent future chikungunya epidemic waves in urban settings.
    FUNDING: Global Virus Network, Burroughs Wellcome Fund, Wellcome Trust, US National Institutes of Health, São Paulo Research Foundation, Brazil Ministry of Education, UK Medical Research Council, Brazilian National Council for Scientific and Technological Development, and UK Royal Society.
    TRANSLATION: For the Portuguese translation of the abstract see Supplementary Materials section.
    DOI:  https://doi.org/10.1016/S2666-5247(23)00033-2
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