bims-mosdis Biomed News
on Mosquito distribution and disease
Issue of 2022‒07‒17
eleven papers selected by
Richard Halfpenny
Staffordshire University
  1. To spray or target mosquitoes another way: focused entomological intelligence guides the implementation of indoor residual spraying in southern Mozambique.
  2. Origins of high latitude introductions of Aedes aegypti to Nebraska and Utah during 2019.
  3. First national-scale evaluation of temephos resistance in Aedes aegypti in Peru.
  4. FIRST REPORT OF AEDES VITTATUS IN ISLAMABAD, PAKISTAN.
  5. The 2021 Zika outbreak in Uttar Pradesh state of India: Tackling the emerging public health threat.
  6. Species Diversity of Anopheles Mosquitoes and Plasmodium vivax Infection Rates, Gyeonggi Province, Republic of Korea During 2020.
  7. Emergence of the invasive Asian bush mosquito Aedes (Hulecoeteomyia) japonicus (Theobald, 1901) in the Czech Republic.
  8. FIRST RECORD OF WYEOMYIA MITCHELLII IN NUEVO LEÓN, MEXICO.
  9. Sero-epidemiological study of arbovirus infection following the 2015-2016 Zika virus outbreak in Cabo Verde.
  10. Dengue and Chikungunya virus circulation in Cameroon and Gabon: molecular evidence among symptomatic individuals.
  11. Asymptomatic Malaria in Households and Neighbors of Laboratory Confirmed Cases in Raya Kobo District, Northeast Ethiopia.
  1. Malar J. 2022 Jul 10. 21(1): 215
    To spray or target mosquitoes another way: focused entomological intelligence guides the implementation of indoor residual spraying in southern Mozambique.
    Celso Alafo, Helena Martí-Soler, Mara Máquina, Arlindo Malheia, Ayesha S Aswat, Lizette L Koekemoer, James Colborn, Neil F Lobo, Allison Tatarsky, Yasmin A Williams, Dulcisária Marrenjo, Nelson Cuamba, Regina Rabinovich, Pedro Alonso, Pedro Aide, Francisco Saúte, Krijn P Paaijmans.
      BACKGROUND: To eliminate malaria in southern Mozambique, the National Malaria Control Programme and its partners are scaling up indoor residual spraying (IRS) activities in two provinces, Gaza and Inhambane. An entomological surveillance planning tool (ESPT) was used to answer the programmatic question of whether IRS would be effective in target geographies, given limited information on local vector bionomics.METHODS: Entomological intelligence was collected in six sentinel sites at the end of the rainy season (April-May 2018) and the beginning of the dry season (June-July 2018). The primary objective was to provide an 'entomological snapshot' by collecting question-based, timely and high-quality data within one single week in each location. Host-seeking behaviour (both indoors and outdoors) was monitored by human-baited tent traps. Indoor resting behaviour was quantified by pyrethrum spray catches and window exit traps.
    RESULTS: Five different species or species groups were identified: Anopheles funestus sensu lato (s.l.) (66.0%), Anopheles gambiae s.l. (14.0%), Anopheles pharoensis (1.4%), Anopheles tenebrosus (14.1%) and Anopheles ziemanni (4.5%). Anopheles funestus sensu stricto (s.s.) was the major vector among its sibling species, and 1.9% were positive for Plasmodium falciparum infections. Anopheles arabiensis was the most abundant vector species within the An. gambiae complex, but none tested positive for P. falciparum infections. Some An. tenebrosus were positive for P. falciparum (1.3%). When evaluating behaviours that impact IRS efficacy, i.e. endophily, the known primary vector An. funestus s.s., was found to rest indoors-demonstrating at least part of its population will be impacted by the intervention if insecticides are selected to which this vector is susceptible. However, other vector species, including An. gambiae s.l., An. tenebrosus, An. pharoensis and An. ziemanni, showed exophilic and exophagic behaviours in several of the districts surveilled.
    CONCLUSION: The targeted approach to entomological surveillance was successful in collecting question-based entomological intelligence to inform decision-making about the use of IRS in specific districts. Endophilic An. funestus s.s. was documented as being the most prevalent and primary malaria vector suggesting that IRS can reduce malaria transmission, but the presence of other vector species both indoors and outdoors suggests that alternative vector control interventions that target these gaps in protection may increase the impact of vector control in southern Mozambique.
    Keywords:  Anopheles surveillance; Entomological indicators; Implementation science; Malaria elimination; Vector control
    DOI:  https://doi.org/10.1186/s12936-022-04233-3
  2. Infect Genet Evol. 2022 Jul 08. pii: S1567-1348(22)00130-7. [Epub ahead of print] 105333
    Origins of high latitude introductions of Aedes aegypti to Nebraska and Utah during 2019.
    Andrea Gloria-Soria, Ary Faraji, Jeff Hamik, Gregory White, Shanon Amsberry, Matthew Donahue, Bryan Buss, Evlyn Pless, Luciano Veiga Cosme, Jeffrey R Powell.
      Aedes aegypti (L.), the yellow fever mosquito, is also an important vector of dengue and Zika viruses, and an invasive species in North America. Aedes aegypti inhabits tropical and sub-tropical areas of the world and in North America, is primarily distributed throughout the southern US states and Mexico. The northern range of Ae. aegypti is limited by cold winter months and establishment in these areas has been mostly unsuccessful. However, frequent introductions of Ae. aegypti to temperate, non-endemic areas during the warmer months can lead to seasonal activity and disease outbreaks. Two Ae. aegypti incursions were reported in the late summer of 2019 into York, Nebraska and Moab, Utah. These states had no history of established populations of this mosquito and no evidence of previous seasonal activity. We genotyped a subset of individuals from each location at 12 microsatellite loci and ~ 14,000 single nucleotide polymorphic markers to determine their genetic affinities to other populations worldwide and investigate their potential source of introduction. Our results support a single origin for each of the introductions from different sources. Aedes aegypti from Utah likely derived from Tucson, Arizona, or a nearby location. Nebraska specimen results were not as conclusive, but point to an origin from southcentral or southeastern US. In addition to an effective, efficient, and sustainable control of invasive mosquitoes, such as Ae. aegypti, identifying the potential routes of introduction will be key to prevent future incursions and assess their potential health threat based on the ability of the source population to transmit a particular virus and its insecticide resistance profile, which may complicate vector control.
    Keywords:  Introduction; Invasive species; Population genetics; Yellow fever mosquito
    DOI:  https://doi.org/10.1016/j.meegid.2022.105333
  3. Parasit Vectors. 2022 Jul 11. 15(1): 254
    First national-scale evaluation of temephos resistance in Aedes aegypti in Peru.
    Miriam Palomino, Jesus Pinto, Pamela Yañez, Anali Cornelio, Luciana Dias, Quesia Amorim, Ademir Jesus Martins, Audrey Lenhart, Jose Bento Pereira Lima.
      BACKGROUND: The development of resistance against insecticides in Aedes aegypti can lead to operational failures in control programs. Knowledge of the spatial and temporal trends of this resistance is needed to drive effective monitoring campaigns, which in turn provide data on which vector control decision-making should be based.METHODS: Third-stage larvae (L3) from the F1 and F2 generations of 39 Peruvian field populations of Ae. aegypti mosquitoes from established laboratory colonies were evaluated for resistance against the organophosphate insecticide temephos. The 39 populations were originally established from eggs collected in the field with ovitraps in eight departments of Peru during 2018 and 2019. Dose-response bioassays, at 11 concentrations of the insecticide, were performed following WHO recommendations.
    RESULTS: Of the 39 field populations of Ae. aegypti tested for resistance to temephos , 11 showed high levels of resistance (resistance ratio [RR] > 10), 16 showed moderate levels of resistance (defined as RR values between 5 and 10) and only 12 were susceptible (RR < 5). The results segregated the study populations into two geographic groups. Most of the populations in the first geographic group, the coastal region, were resistant to temephos, with three populations (AG, CR and LO) showing RR values > 20 (AG 21.5, CR 23.1, LO 39.4). The populations in the second geographic group, the Amazon jungle and the high jungle, showed moderate levels of resistance, with values ranging between 5.1 (JN) and 7.1 (PU). The exception in this geographic group was the population from PM, which showed a RR value of 28.8 to this insecticide.
    CONCLUSIONS: The results of this study demonstrate that Ae. aegypti populations in Peru present different resistance intensities to temephos, 3 years after temephos use was discontinued. Resistance to this larvicide should continue to be monitored because it is possible that resistance to temephos could decrease in the absence of routine selection pressures.
    Keywords:  Aedes aegypti; Arboviruses; Insecticide resistance; Resistance ratio (RR); Temephos; Vector control
    DOI:  https://doi.org/10.1186/s13071-022-05310-x
  4. J Am Mosq Control Assoc. 2022 Jul 15.
    FIRST REPORT OF AEDES VITTATUS IN ISLAMABAD, PAKISTAN.
    Aliya Jabeen, Jamil A Ansari, Aamer Ikram, Mumtaz Ali Khan.
      Aedes vittatus is distributed throughout Asia, Africa, and Europe and can transmit dengue, chikungunya, yellow fever, and Zika viruses. Like other Aedes species, larvae develop in both natural and artificial containers in urban, suburban, and rural areas. In September 2021, an entomological survey was conducted at the National Institute of Health of Pakistan (NIH) and adjacent housing within the NIH colony. All containers with water were examined for Aedes mosquitoes at 150 locations, including residential properties, a plant nursery, junkyards, and recreational parks and playgrounds. A total of 103 larvae, 37 pupae, 5 female and 2 male Ae. vittatus were collected from a fountain. This was the first detection of Ae. vittatus in urban Islamabad. Additional vector surveillance is needed to better understand the geographical distribution, ecology, and behavior of this invasive species and to understand its possible role in the transmission of dengue and chikungunya viruses in Pakistan.
    Keywords:   Aedes vittatus ; Islamabad; Pakistan; chikungunya; dengue
    DOI:  https://doi.org/10.2987/22-7067
  5. Trop Doct. 2022 Jul 12. 494755221113285
    The 2021 Zika outbreak in Uttar Pradesh state of India: Tackling the emerging public health threat.
    Efa Khan, Himanshu Jindal, Priya Mishra, Tarun Kumar Suvvari, Sadhana Jonna.
      Zika virus is an RNA virus belonging to the Flavivirus family that is chiefly transmitted by the female Aedes mosquito. The Zika virus first infected humans in Uganda and Tanzania in 1952. Since, it has spread to several parts of the world causing outbreaks of variable extent. In India, these outbreaks have been reported from Gujarat, Tamil Nadu, Madhya Pradesh, Rajasthan, Kerala, and Maharashtra. The most recent outbreak is from the most populous state of India, Uttar Pradesh, where the climate is conducive to the breeding and transmission of other arboviral infections such as Dengue, Chikungunya, and Malaria. These infections also happen to share similar incubation periods and overlapping clinical manifestations with Zika virus (ZIKV) infection, leading to misdiagnoses or delayed diagnosis. We aim to provide an account of the outbreak, its repercussions, errors made in attempting to contain the spread of the disease, and, measures to be taken in the future.
    Keywords:  Aedes aegypti; Aedes albopictus; Guillain-Barre syndrome; Zika outbreak; arboviral diseases
    DOI:  https://doi.org/10.1177/00494755221113285
  6. J Med Entomol. 2022 Jul 12. pii: tjac086. [Epub ahead of print]
    Species Diversity of Anopheles Mosquitoes and Plasmodium vivax Infection Rates, Gyeonggi Province, Republic of Korea During 2020.
    So Youn Lee, Heung Chul Kim, Terry A Klein, Jihun Ryu, Min Hyeok Won, Jae Won Choi, Myung Soon Kim, Sung Tae Chong, Si Hyeock Lee, Young Ho Kim, Ju Hyeon Kim, Kwang Shik Choi.
      There are currently >300 malaria cases reported annually in the Republic of Korea (ROK), with most cases attributed to exposure in northern Gangwon and Gyeonggi provinces near the demilitarized zone (DMZ). The species diversity and malaria infection rate were determined for a sample of Anopheles mosquitoes collected from May to early November 2020 for six sites in a malaria high-risk area in/near the DMZ and two malaria low-risk areas in southern Gyeonggi province using Mosquito Magnet traps in the ROK. A total of 1864 Anopheles spp. were identified to species by PCR. Overall, An. kleini (31.4%, 510/1622) was the most frequently species assayed, followed by An. pullus (25.5%, 413/1622), An. sineroides (23.9%, 387/1622), and An. sinensis (10.2%, 165/1622), while the other four species only accunted for 9.1% (147/1622) collected in/near the DMZ. Only three species, An. pullus, An. sinensis, and An. sineroides were collected at Humphreys US Army Garrison (USAG) (235 individuals), while only An. sinensis was collected at Yongsan USAG (7 individuals). A total of 36 Anopheles specimens belonging to five species collected in/near the DMZ were positive for Plasmodium vivax by PCR. Anopheles kleini (9) was the most frequent species positive for P. vivax, followed by An. belenrae (8), An. pullus (8), An. sinensis (5), An. sineroides (5), and a member of the Anopheles Lindesayi Complex in the ROK (1). This is the first report of P. vivax in a member of the An. Lindesayi Complex in the ROK. These findings can assist in guiding future malaria vector management in the ROK.
    Keywords:   Anopheles ; Plasmodium vivax ; Republic of Korea
    DOI:  https://doi.org/10.1093/jme/tjac086
  7. Parasit Vectors. 2022 Jul 11. 15(1): 250
    Emergence of the invasive Asian bush mosquito Aedes (Hulecoeteomyia) japonicus (Theobald, 1901) in the Czech Republic.
    Jakub Vojtíšek, Nele Janssen, Silvie Šikutová, Oldřich Šebesta, Helge Kampen, Ivo Rudolf.
      BACKGROUND: Aedes japonicus is a mosquito species native to North-East Asia that was first found established outside its original geographic distribution range in 1998 and has since spread massively through North America and Europe. In the Czech Republic, the species was not reported before 2021.METHODS: Aedes invasive mosquitoes (AIM) are routinely surveyed in the Czech Republic by ovitrapping at potential entry ports. This surveillance is supported by appeals to the population to report uncommon mosquitoes. The submission of an Ae. japonicus specimen by a citizen in 2021 was followed by local search for aquatic mosquito stages in the submitter's garden and short-term adult monitoring with encephalitis virus surveillance (EVS) traps in its surroundings. Collected Ae. japonicus specimens were subjected to nad4 haplotype and microsatellite analyses.
    RESULTS: Aedes japonicus was detected for the first time in the Czech Republic in 2021. Aquatic stages and adults were collected in Prachatice, close to the Czech-German border, and eggs in Mikulov, on the Czech-Austrian border. Morphological identification was confirmed by molecular taxonomy. Genetic analysis of specimens and comparison of genetic data with those of other European populations, particularly from Germany, showed the Prachatice specimens to be most closely related to a German population. The Mikulov specimens were more distantly related to those, with no close relatives identifiable.
    CONCLUSIONS: Aedes japonicus is already widely distributed in Germany and Austria, two countries neighbouring the Czech Republic, and continues to spread rapidly in Central Europe. It must therefore be assumed that the species is already present at more than the two described localities in the Czech Republic and will further spread in this country. These findings highlight the need for more comprehensive AIM surveillance in the Czech Republic.
    Keywords:  Aedes japonicus; Central Europe; Introduction; Invasive species; Surveillance; Vector
    DOI:  https://doi.org/10.1186/s13071-022-05332-5
  8. J Am Mosq Control Assoc. 2022 Jul 15.
    FIRST RECORD OF WYEOMYIA MITCHELLII IN NUEVO LEÓN, MEXICO.
    Aldo I Ortega-Morales, Guillermo Morillón-Borjón, Isis J Morales-Avitia, Antonio A Sánchez-García, Yuri O Ayala-Sulca, Francisco J Sánchez-Rámos.
      On October 5, 2021, mosquito collections were conducted in Nuevo León in search of an undescribed species within the genus Wyeomyia reported previously in this state. Species collected included Aedes quadrivittatus, Ae. amabilis, Ae. triseriatus group, Ae. albopictus, and Wy. mitchellii. Although the undescribed species was not found, the occurrence record for Wy. mitchellii in Nuevo León constitutes the 1st record for this species in this state. Additionally, historical records of the presence of Wy. mitchelli in Mexico, available in the literature, were reviewed and updated. Specimens collected during this study were deposited in the Culicidae Collection of the Parasitology Department, Autonomous Agrarian University Antonio Narro, Laguna unit. With the addition of Wy. mitchellii to the mosquito fauna of Nuevo León, there are currently 67 species in the state.
    Keywords:   Wyeomyia mitchellii ; First record; Mexico; Nuevo León
    DOI:  https://doi.org/10.2987/22-7069
  9. Sci Rep. 2022 Jul 09. 12(1): 11719
    Sero-epidemiological study of arbovirus infection following the 2015-2016 Zika virus outbreak in Cabo Verde.
    Daniel Ward, Ana Rita Gomes, Kevin K A Tetteh, Nuno Sepúlveda, Lara Ferrero Gomez, Susana Campino, Taane G Clark.
      In November 2015, cases of Zika virus infection were recorded in Cabo Verde (Africa), originating from Brazil. The outbreak subsided after seven months with 7580 suspected cases. We performed a serological survey (n = 431) in Praia, the capital city, 3 months after transmission ceased. Serum samples were screened for arbovirus antibodies using ELISA techniques and revealed seroconverted individuals with Zika (10.9%), dengue (1-4) (12.5%), yellow fever (0.2%) and chikungunya (2.6%) infections. Zika seropositivity was predominantly observed amongst females (70%). Using a logistic model, risk factors for increased odds of Zika seropositivity included age, self-reported Zika infection, and dengue seropositivity. Serological data from Zika and dengue virus assays were strongly correlated (Spearman's rs = 0.80), which reduced when using a double antigen binding ELISA (Spearman's rs = 0.54). Overall, our work improves an understanding of how Zika and other arboviruses have spread throughout the Cabo Verde population. It also demonstrates the utility of serological assay formats for outbreak investigations.
    DOI:  https://doi.org/10.1038/s41598-022-16115-4
  10. Access Microbiol. 2022 ;4(4): 000340
    Dengue and Chikungunya virus circulation in Cameroon and Gabon: molecular evidence among symptomatic individuals.
    Ghyslaine Bruna Djeunang Dongho, Giulietta Venturi, Claudia Fortuna, Giacomo Maria Paganotti, Carlo Severini, Mariangela L'Episcopia, Armand Tiotsia Tsapi, Eleonora Benedetti, Giulia Marsili, Antonello Amendola, Giovanni Rezza, Martin Sanou Sobze, Gianluca Russo.
      We report the molecular evidence of dengue virus (DENV) and chikungunya virus (CHIKV) infection in symptomatic individuals in Cameroon and Gabon, respectively. Arthropod-borne viruses (arboviruses) are distributed in the tropical or subtropical regions, with DENV having the highest burden. The morbidity and mortality related to arboviral diseases raise the concern of timely and efficient surveillance and care. Our aim was to assess the circulation of arboviruses [DENV, CHIKV, Zika virus (ZIKV)] among febrile patients in Dschang (West Cameroon) and Kyé-ossi (South Cameroon, border with Gabon and Equatorial Guinea). Dried blood spots were collected from 601 consenting febrile patients, and 194 Plasmodium spp.-negative samples were tested for the molecular detection of cases of DENV, CHIKV and ZIKV infection. Overall, no case of ZIKV infection was found, whereas one case of DENV infection and one case of CHIKV infection were detected in Dschang and Kyé-ossi, respectively, with the CHIKV-infected patient being resident in Gabon. Our findings suggest the need to establish an active surveillance of arbovirus transmission in Cameroon and bordering countries.
    Keywords:  Cameroon; Chikungunya virus; Dengue virus; Gabon; febrile patients; real-time PCR
    DOI:  https://doi.org/10.1099/acmi.0.000340
  11. Ethiop J Health Sci. 2022 May;32(3): 623-630
    Asymptomatic Malaria in Households and Neighbors of Laboratory Confirmed Cases in Raya Kobo District, Northeast Ethiopia.
    Yimer Melese, Megbaru Alemu, Mulat Yimer, Banchamlak Tegegne, Tigist Tadele.
      Background: Malaria is the leading vector-borne parasitic disease that is causing high morbidity and mortality worldwide. So far huge efforts to control and eliminate malaria are hindered by the occurrence of asymptomatic carriers that are a potential source of infection. Yet, there is a scarcity of data nationally and in the current study area as well. Therefore, this study was aimed to assess the prevalence of asymptomatic malaria in Northeast Ethiopia.Methods: A community-based cross-sectional study was conducted in 2019 involving a total of 270 study participants recruited via purposive non-probability sampling technique. A structured questionnaire was used to collect data on sociodemographic characteristics, individual and household factors related to asymptomatic malaria. Data were entered in Epi Data 3.1 version and analyzed by using SPSS version 20, and p< 0.05 was considered statistically significant.
    Results: The overall prevalence of asymptomatic malaria was 7.0%, with 3.0%, 5.2%, and 12.0%, respectively by Rapid diagnostic tests (RDT), Microscopy and Polymerase chain reaction (PCR). The majority of infections (73.7%) were identified from index households. Previous malaria history (AOR: 4.030, 95% CI: 1.021-15.903), living with index cases (AOR: 3.880, 95% CI: 1.275-11.806) and family size > 6 members (AOR: 4.820, 95% CI: 1.260-18.437) were significant predictors of asymptomatic malaria.
    Conclusion: Reactive case detection had identified considerably higher asymptomatic malaria cases in the community. Therefore, active case investigation should be established in the community by tracking the symptomatic cases at the health facilities.
    Keywords:  Asymptomatic malaria; Ethiopia; Raya; Reactive
    DOI:  https://doi.org/10.4314/ejhs.v32i3.19
This page is being maintained by Thomas Krichel. It was last updated on 2022‒08‒16 at 11:36:52.