bims-mosdis Biomed News
on Mosquito distribution and disease
Issue of 2022‒06‒12
thirteen papers selected by
Richard Halfpenny
Staffordshire University
  1. Malaria-Transmitting Vectors Microbiota: Overview and Interactions With Anopheles Mosquito Biology.
  2. Outdoor biting and pyrethroid resistance as potential drivers of persistent malaria transmission in Zanzibar.
  3. Armigeres subalbatus is a potential vector for Zika virus but not dengue virus.
  4. Using an antimalarial in mosquitoes overcomes Anopheles and Plasmodium resistance to malaria control strategies.
  5. Circulation of Dengue Virus Serotype 2 in Humans and Mosquitoes During an Outbreak in El Quseir City, Egypt.
  6. Evaluation of sustainable susceptibility to Plasmodium vivax infection among colonized Anopheles darlingi and Anopheles deaneorum.
  7. [Important arboviral diseases in returning travelers: dengue, chikungunya and zika].
  8. Yellow Fever: A Brief History of a Tropical Virosis.
  9. Relative contribution of low-density and asymptomatic infections to Plasmodium vivax transmission in the Amazon: pooled analysis of individual participant data from population-based cross-sectional surveys.
  10. Vector control strategy for Anopheles stephensi in Africa.
  11. Inkoo and Sindbis viruses in blood sucking insects, and a serological study for Inkoo virus in semi-domesticated Eurasian tundra reindeer in Norway.
  12. Impacts of El Niño Southern Oscillation on the dengue transmission dynamics in the Metropolitan Region of Recife, Brazil.
  13. Vector-Borne Viral Diseases as a Current Threat for Human and Animal Health-One Health Perspective.
  1. Front Microbiol. 2022 ;13 891573
    Malaria-Transmitting Vectors Microbiota: Overview and Interactions With Anopheles Mosquito Biology.
    Oswald Y Djihinto, Adandé A Medjigbodo, Albert R A Gangbadja, Helga M Saizonou, Hamirath O Lagnika, Dyane Nanmede, Laurette Djossou, Roméo Bohounton, Pierre Marie Sovegnon, Marie-Joel Fanou, Romuald Agonhossou, Romaric Akoton, Wassiyath Mousse, Luc S Djogbénou.
      Malaria remains a vector-borne infectious disease that is still a major public health concern worldwide, especially in tropical regions. Malaria is caused by a protozoan parasite of the genus Plasmodium and transmitted through the bite of infected female Anopheles mosquitoes. The control interventions targeting mosquito vectors have achieved significant success during the last two decades and rely mainly on the use of chemical insecticides through the insecticide-treated nets (ITNs) and indoor residual spraying (IRS). Unfortunately, resistance to conventional insecticides currently being used in public health is spreading in the natural mosquito populations, hampering the long-term success of the current vector control strategies. Thus, to achieve the goal of malaria elimination, it appears necessary to improve vector control approaches through the development of novel environment-friendly tools. Mosquito microbiota has by now given rise to the expansion of innovative control tools, such as the use of endosymbionts to target insect vectors, known as "symbiotic control." In this review, we will present the viral, fungal and bacterial diversity of Anopheles mosquitoes, including the bacteriophages. This review discusses the likely interactions between the vector microbiota and its fitness and resistance to insecticides.
    Keywords:  Anopheles; insecticide resistance; malaria; microbiota; mosquito
    DOI:  https://doi.org/10.3389/fmicb.2022.891573
  2. Malar J. 2022 Jun 07. 21(1): 172
    Outdoor biting and pyrethroid resistance as potential drivers of persistent malaria transmission in Zanzibar.
    Revocatus M Musiba, Brian B Tarimo, April Monroe, Dickson Msaky, Halfan Ngowo, Kimberly Mihayo, Alex Limwagu, Godlove T Chilla, Gasper K Shubis, Ahmada Ibrahim, George Greer, Juma H Mcha, Khamis A Haji, Faiza B Abbas, Abdullah Ali, Fredros O Okumu, Samson S Kiware.
      BACKGROUND: Low-level of malaria transmission persist in Zanzibar despite high coverage of core vector control interventions. This study was carried out in hot-spot sites to better understand entomological factors that may contribute to residual malaria transmission in Zanzibar.METHODS: A total of 135 households were randomly selected from six sites and consented to participate with 20-25 households per site. Mosquito vector surveillance was carried out indoors and outdoors from 6:00 pm-7:00 am using miniaturized double net trap (DN-Mini™). Additional collections were done indoors using mouth aspirators to retrieve resting mosquitoes from wall and ceiling surfaces, and outdoors using resting bucket and pit traps. All collected mosquitoes were morphologically and genetically (PCR) analysed in the laboratory. All collected anopheline and blood-fed mosquitoes were analysed for sporozoite infection and blood meal host preferences by Circumsporozoite Protein ELISA and blood meal ELISA, respectively. The differences between indoor and outdoor mosquito biting rates were analysed using generalized linear mixed models. Levels of resistance to commonly used insecticides were quantified by WHO susceptibility tests.
    RESULTS: Out of 704 malaria vectors collected across 135 households, PCR analysis shows that 98.60% were Anopheles arabiensis, 0.6% Anopheles merus and 0.6% Anopheles gambiae sensu stricto. Sporozoite ELISA analysis indicates that all mosquitoes were negative for the malaria parasite. The results show that more An. arabiensis were collected outdoor (~ 85%) compared to indoor (~ 15%). Furthermore, large numbers of An. arabiensis were caught in outdoor resting sites, where the pit trap (67.2%) collected more mosquitoes compared to the outdoor DN-Mini trap (32.8%). Nearly two-thirds (60.7%) of blood-fed mosquitoes had obtained blood meals from non-human hosts. Mosquitoes displayed non-uniform susceptibility status and resistance intensity among the tested insecticides across the study sites to all WHO recommended insecticides across the study sites.
    CONCLUSION: This study suggests that in contexts such as Zanzibar, testing of novel techniques to complement indoor protection and targeting outdoor biting and/or resting mosquitoes, may be warranted to complement existing interventions and contribute to malaria elimination efforts. The study highlights the need to implement novel interventions and/or adaptations of strategies that can target outdoors biting mosquitoes.
    Keywords:  Entomology; Insecticide resistance; Malaria transmission; Novel tools; Pyrethroids
    DOI:  https://doi.org/10.1186/s12936-022-04200-y
  3. Infect Dis Poverty. 2022 Jun 04. 11(1): 62
    Armigeres subalbatus is a potential vector for Zika virus but not dengue virus.
    Wenqiang Yang, Siyu Zhao, Yugu Xie, Tong Liu, Ling Kong, Yijia Guo, Zhensheng Xie, Peiwen Liu, Xiao-Guang Chen.
      BACKGROUND: Zika virus (ZIKV) and dengue virus (DENV) are closely related flaviviruses primarily transmitted by Aedes mosquitoes. Armigeres subalbatus is an emerging and widely distributed mosquito, and ZIKV has been detected and isolated from it. However, it is not clear whether Ar. subalbatus could be a vector for ZIKV and DENV or not. In this study, we investigated the infection and transmission of Ar. subalbatus to ZIKV and DENV.METHODS: A line of Ar. subalbatus was isolated from Guangdong, China, and further identified by the mitochondrial cytochrome oxidase subunit 1 (COI) gene. The adults of Ar. subalbatus were fed with blood meal containing ZIKV or DENV-2. At 4, 7, 10, 14, and 21 days post-inoculation (dpi), the infections of ZIKV or DENV-2 in the midguts, ovaries and salivary glands were detected and quantified by RT-PCR and RT-qPCR. To assess the transmissibility, suckling mice were exposed to bites of ZIKV-infected mosquitoes, and ZIKV was detected in brain tissue by RT-qPCR and plaque assays. Furthermore, the larvae of Ar. subalbatus were reared in artificial urine containing ZIKV or DENV-2. The infection rates and viral titers of larvae and adults were analyzed by RT-PCR and RT-qPCR, and the viral distribution in larval tissues was observed by immunohistochemistry. Chi-square test and one-way ANOVA analysis were used for assessing the infection rate and viral titer in varied tissues and different time points, respectively.
    RESULTS: Following oral inoculation, ZIKV but not DENV-2 could be detected in Ar. subalbatus midguts at 4 dpi, ovaries at 7 dpi and salivary glands at 10 dpi. The highest infection rate (IR) of ZIKV was 27.8% in midgut at 7 dpi, 9.7% in ovary and 5.6% in salivary gland at 21 dpi. Eight days after being bitten by ZIKV-positive mosquitoes, ZIKV was detected in three brain tissues out of four suckling mice exposed to bites. ZIKV could be detected in the larvae reared in artificial urine contained ZIKV at a high concentration of 105 pfu/ml and various tissues of adults with a low infection rate (0.70-1.35%). ZIKV could be observed in anal papillae and midgut of larvae at 4 dpi under laboratory conditions.
    CONCLUSIONS: ZIKV but not DENV-2 can infect Ar. subalbatus by blood meal and artificial urine, and the infected mosquitoes can transmit ZIKV to suckling mice by bite. From these findings, we can conclude that the Ar. subalbatus isolated from Guangdong province, China, is a potential vector for ZIKV and should therefore be considered in vector control programs to prevent and control of Zika virus disease.
    Keywords:  Armigeres subalbatus; Dengue virus; Vector; Zika virus
    DOI:  https://doi.org/10.1186/s40249-022-00990-0
  4. PLoS Pathog. 2022 Jun 10. 18(6): e1010609
    Using an antimalarial in mosquitoes overcomes Anopheles and Plasmodium resistance to malaria control strategies.
    Douglas G Paton, Alexandra S Probst, Erica Ma, Kelsey L Adams, W Robert Shaw, Naresh Singh, Selina Bopp, Sarah K Volkman, Domombele F S Hien, Prislaure S L Paré, Rakiswendé S Yerbanga, Abdoullaye Diabaté, Roch K Dabiré, Thierry Lefèvre, Dyann F Wirth, Flaminia Catteruccia.
      The spread of insecticide resistance in Anopheles mosquitoes and drug resistance in Plasmodium parasites is contributing to a global resurgence of malaria, making the generation of control tools that can overcome these roadblocks an urgent public health priority. We recently showed that the transmission of Plasmodium falciparum parasites can be efficiently blocked when exposing Anopheles gambiae females to antimalarials deposited on a treated surface, with no negative consequences on major components of mosquito fitness. Here, we demonstrate this approach can overcome the hurdles of insecticide resistance in mosquitoes and drug resistant in parasites. We show that the transmission-blocking efficacy of mosquito-targeted antimalarials is maintained when field-derived, insecticide resistant Anopheles are exposed to the potent cytochrome b inhibitor atovaquone, demonstrating that this drug escapes insecticide resistance mechanisms that could potentially interfere with its function. Moreover, this approach prevents transmission of field-derived, artemisinin resistant P. falciparum parasites (Kelch13 C580Y mutant), proving that this strategy could be used to prevent the spread of parasite mutations that induce resistance to front-line antimalarials. Atovaquone is also highly effective at limiting parasite development when ingested by mosquitoes in sugar solutions, including in ongoing infections. These data support the use of mosquito-targeted antimalarials as a promising tool to complement and extend the efficacy of current malaria control interventions.
    DOI:  https://doi.org/10.1371/journal.ppat.1010609
  5. Infect Drug Resist. 2022 ;15 2713-2721
    Circulation of Dengue Virus Serotype 2 in Humans and Mosquitoes During an Outbreak in El Quseir City, Egypt.
    Asmaa M El-Kady, Heba A Osman, Mohamed Farouk Alemam, Dina Marghani, Mohammed A Shanawaz, Majed H Wakid, Wafa Abdullah I Al-Megrin, Hatem A Elshabrawy, Osama H Abdella, Khaled S Allemailem, Ahmad Almatroudi, Mostafa I El-Amir.
      Introduction: In recent decades, the rate of infection with dengue virus (DENV) has risen significantly, now affecting nearly 400 million individuals annually. Dengue fever among humans is caused via specific mosquito vectors bites. Sporadic cases have been reported in Egypt. The goal of this study was to identify the serotype of the DENV outbreak in both human and mosquito vector along the coast of the Red Sea, Upper Egypt, in 2017. Identification of the serotype of the virus may help identify its source and assist in applying epidemiological and control measures.Materials and Methods: The current study was carried out in El Quseir City, Red Sea Governorate, Upper Egypt, on 144 patients complaining of symptoms indicative of dengue fever at the time of the 2017 Egypt outbreak. Human blood samples and the mosquito reservoirs were identified as having dengue virus infection serologically and molecularly.
    Results: Overall, 97 (67.4%) patients were positive for dengue virus IgM antibodies. Molecular examination of the human samples and pools of mosquitoes revealed that DENV-2 virus was the serotype responsible for the outbreak. Only one pool of female mosquitoes containing Aedes aegypti was infected with dengue fever virus (DENV-2).
    Conclusion: This was the first serotyping of the DENV responsible for dengue virus outbreak in Egypt in 2017. Determining the serotype of dengue virus can help to avoid and monitor outbreaks. The serotype identified in this study was DENV-2, while DENV-1 was the serotype found in the previous outbreak in 2015 in the province of Assiut. This study thus raises concerns that a new dengue serotype could have been introduced into Egypt. It is necessary for a comprehensive risk assessment to be carried out in the country, including an entomological survey, to assess the presence and potential geographical expansion of mosquito vectors there.
    Keywords:  Upper Egypt; dengue fever; human; mosquito; multiplex PCR; serotyping
    DOI:  https://doi.org/10.2147/IDR.S360675
  6. Malar J. 2022 Jun 03. 21(1): 163
    Evaluation of sustainable susceptibility to Plasmodium vivax infection among colonized Anopheles darlingi and Anopheles deaneorum.
    Najara A C Santos, Alice O Andrade, Thais C Santos, Leandro N Martinez, Amália S Ferreira, Alessandra S Bastos, Mirilene M Martins, José D C Pontual, Carolina B G Teles, Jansen F Medeiros, Maisa S Araújo.
      BACKGROUND: The colonization of mosquitoes susceptible to Plasmodium vivax via direct membrane feeding assay (DMFA) has the potential to significantly advance our knowledge of P. vivax biology, vector-parasite interaction and transmission-blocking vaccine research. Anopheles darlingi and Anopheles deaneorum are important vectors of malaria in the Western Brazilian Amazon. Since 2018, well-established colonies of these species have been maintained in order to mass produce mosquitoes destined for P. vivax infection. Plasmodium susceptibility was confirmed when the colonies were established, but susceptibility needs to be maintained for these colonies to remain good models for pathogen transmission. Thus, the susceptibility was assessed of colonized mosquitoes to P. vivax isolates circulating in the Western Amazon.METHODS: Laboratory-reared mosquitoes from F10-F25 generations were fed on P. vivax blood isolates via DMFA. Susceptibility was determined by prevalence and intensity of infection as represented by oocyst load seven days after blood feeding, and sporozoite load 14 days after blood feeding. The effect of infection on mosquito survival was evaluated from initial blood feeding until sporogonic development and survival rates were compared between mosquitoes fed on infected and uninfected blood. Correlation was calculated between gametocytaemia and prevalence/intensity of infection, and between oocyst and sporozoite load.
    RESULTS: Significant differences were found in prevalence and intensity of infection between species. Anopheles darlingi showed a higher proportion of infected mosquitoes and higher oocyst and sporozoite intensity than An. deaneorum. Survival analysis showed that An. deaneorum survival decreased drastically until 14 days post infection (dpi). Plasmodium vivax infection decreased survival in both species relative to uninfected mosquitoes. No correlation was observed between gametocytaemia and prevalence/intensity of infection, but oocyst and sporozoite load had a moderate to strong correlation.
    CONCLUSIONS: Colonized An. darlingi make excellent subjects for modelling pathogen transmission. On the other hand, An. deaneorum could serve as a model for immunity studies due the low susceptibility under current colonized conditions. In the application of DMFA, gametocyte density is not a reliable parameter for predicting mosquito infection by P. vivax, but oocyst intensity should be used to schedule sporozoite experiments.
    Keywords:  Anopheles darlingi; Anopheles deaneorum; Colony; DMFA; Gametocytaemia; Plasmodium vivax; Survival; Susceptibility
    DOI:  https://doi.org/10.1186/s12936-022-04204-8
  7. Dtsch Med Wochenschr. 2022 Jun;147(12): 755-767
    [Important arboviral diseases in returning travelers: dengue, chikungunya and zika].
    Astrid Niederfahrenhorst, Camilla Rothe.
      Arboviral infections are an important differential diagnosis in returning travelers with fever, muscle or joint pain and rash. Arboviruses have spread widely around the globe in the last decades. The most common arboviral infections in returning travelers from tropical and subtropical areas are dengue, chikungunya and zika. Their most important vectors, Aedes (Stegomyia) mosquito species, have adapted to the urban environment, which enabled arboviruses to establish urban transmission cycles. Population growth, urbanization, globalization, modern means of transportation and global warming are speeding up their spread.Laboratory confirmation of an arboviral infection can generally be obtained by direct virus detection (PCR, antigen test) in the first week of illness; from the second week of illness serology can be used. Treatment is mostly symptomatic.Dengue fever is the most common cause of fever in returning travelers from South-East Asia. Patients have to be educated about and observed for warning signs of severe dengue that can rarely develop around day 5 of the disease and is marked by a rise in hematocrit.Chikungunya mostly occurs in epidemics and is characterized by severe and often long-lasting arthritis.Preconceptional screening for zika virus infection is not recommended. Instead, travelers should delay conception for up to three months after returning from a zika endemic area.Dengue, chikungunya and zika vaccine development has been hampered by difficulties, for example antibody-dependent-enhancement or the unpredictability of outbreaks, and up to now no vaccines for travelers have been licensed. Yet several promising vaccine candidates are currently under development.
    DOI:  https://doi.org/10.1055/a-1661-3847
  8. Presse Med. 2022 Jun 03. pii: S0755-4982(22)00025-2. [Epub ahead of print] 104132
    Yellow Fever: A Brief History of a Tropical Virosis.
    Francois Rodhain.
      Yellow fever is a zoonotic arbovirosis, the agent of which is transmitted by mosquitoes. In humans, this virus can cause hemorrhagic hepato-nephritis, while mild or inapparent infections are common. The catastrophic epidemics that occurred, mainly in the 18th and the 19th centuries, in Latin America and the United States as well as in the port cities of West Africa and Europe, had considerable demographic, socio-economic and political repercussions. The viral nature of the infectious agent and its transmission by the Aedes aegypti mosquito, previously suspected by Beauperthuy, were demonstrated by Carlos Finlay in 1881 and confirmed by the American Commission led by Walter Reed in Havana in 1900 and by the French Commission led by Emile Marchoux in Rio de Janeiro in 1901-1905. The control of Ae. aegypti could then be implemented effectively. It was only in 1927 that the yellow fever virus was isolated in Africa, its continent of origin, by French researchers from the Pasteur Institute in Dakar and by the American and English teams of the Rockefeller Foundation. Soon after, epidemiologists realized that there were forest cycles of the virus, involving monkeys and vectors other than Ae. aegypti, and consequently recognized the existence of a wild reservoir of the virus. Once the virus was isolated, work on vaccine development could begin. This research was carried out by the Institut Pasteur in Dakar and by the Rockefeller Foundation. The two teams succeeded in obtaining two live vaccines conferring excellent and long-lasting protection: the neurotropic "Dakar" vaccine (1934) and the "Rockefeller" 17D vaccine (1937), which was better tolerated. From then on, the fight against of yellow fever involved entomological control and vaccine protection, and it was a huge success until the 1960s. Unfortunately, the control programs were gradually reduced, and in some countries terminated. This resulted in the return of Ae. aegypti in urban areas and in insufficient vaccination coverage. Risks of epidemics reappeared, in Latin America as well as Africa. In the early 21st century, epidemiologists are worried about these resurgences, especially since we still have no indisputable explanation for the absence of the disease on the Asian continent. Obviously, yellow fever is not a disease of the past.
    DOI:  https://doi.org/10.1016/j.lpm.2022.104132
  9. Lancet Reg Health Am. 2022 May;pii: 100169. [Epub ahead of print]9
    Relative contribution of low-density and asymptomatic infections to Plasmodium vivax transmission in the Amazon: pooled analysis of individual participant data from population-based cross-sectional surveys.
    Marcelo U Ferreira, Rodrigo M Corder, Igor C Johansen, Johanna H Kattenberg, Marta Moreno, Angel Rosas-Aguirre, Simone Ladeia-Andrade, Jan E Conn, Alejandro Llanos-Cuentas, Dionicia Gamboa, Anna Rosanas-Urgell, Joseph M Vinetz.
      Background: Low-density and asymptomatic Plasmodium vivax infections remain largely undetected and untreated and may contribute significantly to malaria transmission in the Amazon.Methods: We analysed individual participant data from population-based surveys that measured P vivax prevalence by microscopy and polymerase chain reaction (PCR) between 2002 and 2015 and modelled the relationship between parasite density and infectiousness to vectors using membrane feeding assay data. We estimated the proportion of sub-patent (i.e., missed by microscopy) and asymptomatic P vivax infections and examined how parasite density relates to clinical manifestations and mosquito infection in Amazonian settings.
    Findings: We pooled 24,986 observations from six sites in Brazil and Peru. P vivax was detected in 6·8% and 2·1% of them by PCR and microscopy, respectively. 58·5% to 92·6% of P vivax infections were asymptomatic and 61·2% to 96·3% were sub-patent across study sites. P vivax density thresholds associated with clinical symptoms were one order of magnitude higher in children than in adults. We estimate that sub-patent parasite carriers are minimally infectious and contribute 12·7% to 24·9% of the community-wide P vivax transmission, while asymptomatic carriers are the source of 28·2% to 79·2% of mosquito infections.
    Interpretation: Asymptomatic P vivax carriers constitute a vast infectious reservoir that, if targeted by malaria elimination strategies, could substantially reduce malaria transmission in the Amazon. Infected children may remain asymptomatic despite high parasite densities that elicit clinical manifestations in adults.
    Funding: US National Institutes of Health, Fundação de Amparo à Pesquisa do Estado de São Paulo, and Belgium Development Cooperation.
    Keywords:  Amazon; Plasmodium vivax; asymptomatic infections; fever threshold; malaria; sub-patent infections
    DOI:  https://doi.org/10.1016/j.lana.2021.100169
  10. Lancet Microbe. 2022 Jun;pii: S2666-5247(22)00039-8. [Epub ahead of print]3(6): e403
    Vector control strategy for Anopheles stephensi in Africa.
    Ayman Ahmed, Mustafa Abubakr, Yousif Ali, Emmanuel Edwar Siddig, Nouh S Mohamed.
      
    DOI:  https://doi.org/10.1016/S2666-5247(22)00039-8
  11. Virol J. 2022 Jun 03. 19(1): 99
    Inkoo and Sindbis viruses in blood sucking insects, and a serological study for Inkoo virus in semi-domesticated Eurasian tundra reindeer in Norway.
    Ruchika Shakya, Morten Tryland, Rose Vikse, Javier Sánchez Romano, Kjetil Åsbakk, Ingebjørg H Nymo, Reidar Mehl, Magnus Evander, Clas Ahlm, Olli Vapalahti, Olivia Wesula Lwande, Niina Putkuri, Wenche Johansen, Arnulf Soleng, Kristin S Edgar, Åshild K Andreassen.
      BACKGROUND: Mosquito-borne viruses pose a serious threat to humans worldwide. There has been an upsurge in the number of mosquito-borne viruses in Europe, mostly belonging to the families Togaviridae, genus Alphavirus (Sindbis, Chikungunya), Flaviviridae (West Nile, Usutu, Dengue), and Peribunyaviridae, genus Orthobunyavirus, California serogroup (Inkoo, Batai, Tahyna). The principal focus of this study was Inkoo (INKV) and Sindbis (SINV) virus circulating in Norway, Sweden, Finland, and some parts of Russia. These viruses are associated with morbidity in humans. However, there is a knowledge gap regarding reservoirs and transmission. Therefore, we aimed to determine the prevalence of INKV and SINV in blood sucking insects and seroprevalence for INKV in semi-domesticated Eurasian tundra reindeer (Rangifer tarandus tarandus) in Norway.MATERIALS AND METHODS: In total, 213 pools containing about 25 blood sucking insects (BSI) each and 480 reindeer sera were collected in eight Norwegian reindeer summer pasture districts during 2013-2015. The pools were analysed by RT-PCR to detect INKV and by RT-real-time PCR for SINV. Reindeer sera were analysed for INKV-specific IgG by an Indirect Immunofluorescence Assay (n = 480, IIFA) and a Plaque Reduction Neutralization Test (n = 60, PRNT).
    RESULTS: Aedes spp. were the most dominant species among the collected BSI. Two of the pools were positive for INKV-RNA by RT-PCR and were confirmed by pyrosequencing. The overall estimated pool prevalence (EPP) of INKV in Norway was 0.04%. None of the analysed pools were positive for SINV. Overall IgG seroprevalence in reindeer was 62% positive for INKV by IIFA. Of the 60 reindeer sera- analysed by PRNT for INKV, 80% were confirmed positive, and there was no cross-reactivity with the closely related Tahyna virus (TAHV) and Snowshoe hare virus (SSHV).
    CONCLUSION: The occurrence and prevalence of INKV in BSI and the high seroprevalence against the virus among semi-domesticated reindeer in Norway indicate that further studies are required for monitoring this virus. SINV was not detected in the BSI in this study, however, human cases of SINV infection are yearly reported from other regions such as Rjukan in south-central Norway. It is therefore essential to monitor both viruses in the human population. Our findings are important to raise awareness regarding the geographical distribution of these mosquito-borne viruses in Northern Europe.
    Keywords:  Arbovirus; Blood sucking insects (BSI); Estimated pooled prevalence; IIFA; INKV; Mosquito; Prevalence; Reindeer; SINV; Seroprevalence
    DOI:  https://doi.org/10.1186/s12985-022-01815-0
  12. Rev Soc Bras Med Trop. 2022 ;pii: S0037-86822022000100317. [Epub ahead of print]55 e0671
    Impacts of El Niño Southern Oscillation on the dengue transmission dynamics in the Metropolitan Region of Recife, Brazil.
    Henrique Dos Santos Ferreira, Ranyére Silva Nóbrega, Pedro Vinícius da Silva Brito, Jéssica Pires Farias, Jaime Henrique Amorim, Elvis Bergue Mariz Moreira, Érick Carvalho Mendez, Wilson Barros Luiz.
      BACKGROUND: This research addresses two questions: (1) how El Niño Southern Oscillation (ENSO) affects climate variability and how it influences dengue transmission in the Metropolitan Region of Recife (MRR), and (2) whether the epidemic in MRR municipalities has any connection and synchronicity.METHODS: Wavelet analysis and cross-correlation were applied to characterize seasonality, multiyear cycles, and relative delays between the series. This study was developed into two distinct periods. Initially, we performed periodic dengue incidence and intercity epidemic synchronism analyses from 2001 to 2017. We then defined the period from 2001 to 2016 to analyze the periodicity of climatic variables and their coherence with dengue incidence.
    RESULTS: Our results showed systematic cycles of 3-4 years with a recent shortening trend of 2-3 years. Climatic variability, such as positive anomalous temperatures and reduced rainfall due to changes in sea surface temperature (SST), is partially linked to the changing epidemiology of the disease, as this condition provides suitable environments for the Aedes aegypti lifecycle.
    CONCLUSION: ENSO may have influenced the dengue temporal patterns in the MRR, transiently reducing its main way of multiyear variability (3-4 years) to 2-3 years. Furthermore, when the epidemic coincided with El Niño years, it spread regionally and was highly synchronized.
    DOI:  https://doi.org/10.1590/0037-8682-0671-2021
  13. J Clin Med. 2022 May 27. pii: 3026. [Epub ahead of print]11(11):
    Vector-Borne Viral Diseases as a Current Threat for Human and Animal Health-One Health Perspective.
    Wojciech Socha, Malgorzata Kwasnik, Magdalena Larska, Jerzy Rola, Wojciech Rozek.
      Over the last decades, an increase in the emergence or re-emergence of arthropod-borne viruses has been observed in many regions. Viruses such as dengue, yellow fever, or zika are a threat for millions of people on different continents. On the other hand, some arboviruses are still described as endemic, however, they could become more important in the near future. Additionally, there is a group of arboviruses that, although important for animal breeding, are not a direct threat for human health. Those include, e.g., Schmallenberg, bluetongue, or African swine fever viruses. This review focuses on arboviruses and their major vectors: mosquitoes, ticks, biting midges, and sandflies. We discuss the current knowledge on arbovirus transmission, ecology, and methods of prevention. As arboviruses are a challenge to both human and animal health, successful prevention and control are therefore only possible through a One Health perspective.
    Keywords:  One Health perspective; arbovirus transmission; arboviruses; arthropod vectors; vaccines
    DOI:  https://doi.org/10.3390/jcm11113026
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