DengueChat: A Social and Software Platform for Community-based Arbovirus Vector Control

The mosquito Aedes aegypti transmits arboviral diseases at extraordinary rates. Dengue alone afflicts 50 to 100 million people each year, with more than 3 billion at risk globally. This indicates that current approaches to prevention and control are inadequate, and that a paradigm shift from one that largely promotes vertical chemical-based control and vaccine development to one that also concentrates on eliminating the mosquito through actions by the communities it plagues is necessary. We have developed a new social and software platform, DengueChat (denguechat.org), to advance community interventions in arbovirus vector control. It is an interactive platform combining open-source digital communication technologies with face-to-face assemblies. It promotes resident participation in evidence collection, reporting, and analysis, and it incorporates pedagogic information, key messaging, and game concepts to motivate communities to implement vector reduction strategies. Using DengueChat, we conducted a 19-month pilot study in five neighborhoods of Managua, Nicaragua. The results strongly suggest that using the software produced value-added features that enhance community engagement. We measured the entomological and behavioral impacts at different time points and relative risk reduction of entomological indices at the end of the study. The entomological results showed significant risk reductions in disease transmission: Ae. aegypti larvae and pupae indices were reduced by approximately 44% in neighborhoods using DengueChat during one epidemic year, whereas control neighborhoods experienced an increase of more than 500%. A cluster permutation test determined that the probability of household positivity was significantly reduced in neighborhoods that participated in DengueChat compared with the reference neighborhoods (P = 0.0265). Therefore, DengueChat is a promising resource for vector control.

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Additional evidence on the efficacy of different Akirin vaccines assessed on Anopheles arabiensis (Diptera: Culicidae)

Parasites & Vectors ◽

10.1186/s13071-021-04711-8 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Blaženka D. Letinić ◽

Marinela Contreras ◽

Yael Dahan-Moss ◽

Ingrid Linnekugel ◽

José de la Fuente ◽

...

Keyword(s):

Vector Control ◽

Aedes Albopictus ◽

Malaria Vector ◽

Vaccine Efficacy ◽

Anopheles Arabiensis ◽

Vaccine Development ◽

Target Antigen ◽

Control Methods ◽

Protective Response ◽

Current Vector

Abstract Background Anopheles arabiensis is an opportunistic malaria vector that rests and feeds outdoors, circumventing current indoor vector control methods. Furthermore, this vector will readily feed on both animals and humans. Targeting this vector while feeding on animals can provide an additional intervention for the current vector control activities. Previous results have displayed the efficacy of using Subolesin/Akirin ortholog vaccines for the control of multiple ectoparasite infestations. This made Akirin a potential antigen for vaccine development against An. arabiensis. Methods The efficacy of three antigens, namely recombinant Akirin from An. arabiensis, recombinant Akirin from Aedes albopictus, and recombinant Q38 (Akirin/Subolesin chimera) were evaluated as novel interventions for An. arabiensis vector control. Immunisation trials were conducted based on the concept that mosquitoes feeding on vaccinated balb/c mice would ingest antibodies specific to the target antigen. The antibodies would interact with the target antigen in the arthropod vector, subsequently disrupting its function. Results All three antigens successfully reduced An. arabiensis survival and reproductive capacities, with a vaccine efficacy of 68–73%. Conclusions These results were the first to show that hosts vaccinated with recombinant Akirin vaccines could develop a protective response against this outdoor malaria transmission vector, thus providing a step towards the development of a novel intervention for An. arabiensis vector control. Graphic Abstract

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Kiberbiztonság a koronavírus idején – a COVID–19 nemzetbiztonsági aspektusai

Scientia et Securitas ◽

10.1556/112.2021.00001 ◽

2021 ◽

Vol 2 (1) ◽

pp. 78-87

Author(s):

Tamás Palicz ◽

Balázs Bencsik ◽

Miklós Szócska

Keyword(s):

Cyber Security ◽

Vaccine Development ◽

Significant Risk ◽

Significant Risk Factor ◽

Distance Measures ◽

Data Traffic ◽

Home Office ◽

Emergency Case ◽

Wide Range ◽

Almost All

Összefoglaló. A COVID–19 pandémia az információbiztonság területén új kihívásokat jelentett. A távolról végzett munka különböző formái jelentős mértékben növelték az online tér biztonsági kockázatát. Nőtt a hálózatok nagysága, az adatforgalom, és azon felhasználók száma, akiknek nem volt érdemi tapasztalatuk az online térben. A járvány ideje alatt a kibertérből érkező támadások szektoronként és időszakonként eltérő intenzitásúak voltak, a támadások típusa a phishingtől a malwareken keresztül az információs zavarkeltésig széles spektrumban változott. Számos jelenségnek nemzetbiztonsági vonatkozásai is voltak. Összefoglaló cikkünkben a fenti jelenségek nemzetközi és hazai tapasztalatait összegezzük, különös figyelmet szentelve az egészségügyi rendszernek, illetve a vakcinafejlesztés kibertérből érkező fenyegetéseinek. Summary. During the COVID-19 pandemic, new challenges emerged in the field of information security and cyber security. Home office, home schooling and distance learning, or even telemedicine hit some organizations unprepared. Security risks in online space have increased significantly: the number of network endpoints and the number of computers, laptops and mobile devices have increased with network data traffic as well as the number of users who had no significant experience in online space. They appeared as a significant risk factor. This has been exacerbated, especially in healthcare, by the extremely high workload, which has made systems highly vulnerable. During the epidemic, attacks from cyberspace varied in intensity from sector to sector and period to period. Statistics from international and national organizations have shown that from the end of the first quarter of 2020, the number of cyber security incidents jumped sharply and then remained high even after a small decline. The types of attacks had an extremely wide range: from phishing through malware to misinformation, almost all types of attacks occurred. Many phenomena also had national security implications. Ransomware virus attacks on health have affected almost all health systems and reached high levels by the end of 2020 in particular. It was during the first period that, in an emergency case, there is thought to be an association between a ransomware virus attack and the death of a patient who was not admitted because of the attack. In addition to distance measures and the associated increase in cyber threats, the emerging threats related to vaccination, which is central to the fight against the epidemic, should also be highlighted. This period has shed light on how many vulnerabilities there are, from vaccine development through drug trials to delivery to vaccines and the organization of vaccines, that cybercriminals are able to attack. In order to prevent and combat these threats and attacks, and to respond appropriately, complex, multidisciplinary collaborations are needed in which security science has a privileged place. In our review article, we summarize the international and national experiences of the above phenomena, paying special attention to the health care system and the threats coming from cyberspace in vaccine development.

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Environmental Vector Control Practices among Households of Patients with Dengue Fever during the Epidemic of 2018 in Kerala, India

Journal of Evidence Based Medicine and Healthcare ◽

10.18410/jebmh/2021/10 ◽

2021 ◽

Vol 8 (02) ◽

pp. 48-52

Author(s):

Chintha Sujatha ◽

Reshma Rajan Sudha ◽

Sreejith Lalitha Krishnankutty ◽

Prajitha Kannamkottapilly Chandrasekharan

Keyword(s):

Vector Control ◽

Dengue Fever ◽

Protective Factor ◽

Significant Risk ◽

Public Health Problem ◽

Community Level ◽

Control Measures ◽

Major Public Health Problem ◽

Cross Sectional ◽

Breeding Habitats

BACKGROUND Dengue fever is a major public health problem in Kerala. Vector control measures practiced at household level is the most cost-effective way of controlling dengue. This study aims to assess environmental measures of vector control practised among households of suspected or confirmed dengue patients in Thiruvananthapuram district of Kerala. METHODS A cross sectional study was done among households of patients diagnosed with dengue fever and reported in Integrated Disease Surveillance Programme (IDSP) in Thiruvananthapuram district from June to December 2018. Investigators interviewed the household members and made direct observations to collect data on vector control practices using a structured questionnaire. RESULTS A total of 108 houses were surveyed. Potential breeding habitats were found in 58 (53.7 %) houses. Aedes larva was found in containers from four (3.7 %) houses. Dry day observance was not regular with only 5 (4.6 %) houses practicing it weekly. Waste management practiced was proper in 47 (43.5 %) houses. Community level pre monsoon preparedness for epidemics was done in the vicinity of 53 (49.1 %) houses and it was found to be a protective factor against presence of breeding habitats in and around houses (p = 0.013). Low education (p = 0.012) and low occupational status (p = 0.017) were found to be significant risk factors. CONCLUSIONS Even during an epidemic, with occurrence of infections in the family, only half of the households are practising adequate vector control methods. Community level interventions and targeted information education campaign will help improve practice of environmental methods of vector control in dengue. KEYWORDS Dengue, Vector Control, Aedes Control, Environmental Methods, Community Interventions

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Modeling the Effects of Spatial Heterogeneity and Seasonality on Guinea Worm Disease Transmission

Journal of Applied Mathematics ◽

10.1155/2018/5084687 ◽

2018 ◽

Vol 2018 ◽

pp. 1-12 ◽

Cited By ~ 1

Author(s):

Anthony A. E. Losio ◽

Steady Mushayabasa

Keyword(s):

Spatial Heterogeneity ◽

Vector Control ◽

Disease Transmission ◽

Disease Surveillance ◽

Neglected Tropical Diseases ◽

South Sudan ◽

Model Parameters ◽

Guinea Worm ◽

Infection Dynamics ◽

And Control

Guinea worm disease is one of the neglected tropical diseases that is on the verge of elimination. Currently the disease is endemic in four countries, namely, Ethiopia, Mali, Chad, and South Sudan. Prior studies have demonstrated that climate factors and limited access to safe drinking water have a significant impact on transmission and control of Guinea worm disease. In this paper, we present a new mathematical model to understand the transmission dynamics of Guinea worm disease in South Sudan. The model incorporates seasonal variations, educational campaigns, and spatial heterogeneity. Both qualitative and quantitative analysis of the model have been carried out. Utilizing Guinea worm disease surveillance data of South Sudan (2007-2013) we estimate the model parameters. Meanwhile, we perform an optimal control study to evaluate the implications of vector control on long-term Guinea worm infection dynamics. Our results demonstrate that vector control could play a significant role on Guinea worm disease eradication.

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Cryptic Wolbachia (Rickettsiales: Rickettsiaceae) Detection and Prevalence in Culicoides (Diptera: Ceratopogonidae) Midge Populations in the United States

Journal of Medical Entomology ◽

10.1093/jme/tjaa003 ◽

2020 ◽

Vol 57 (4) ◽

pp. 1262-1269 ◽

Cited By ~ 4

Author(s):

Hunter Covey ◽

Rafe H Hall ◽

Alyssa Krafsur ◽

Megan L Matthews ◽

Phillip T Shults ◽

...

Keyword(s):

United States ◽

Vector Control ◽

Disease Transmission ◽

The United States ◽

Hemorrhagic Disease ◽

Human Pathogens ◽

Control Approach ◽

16S Gene ◽

Culicoides Sonorensis

Abstract Culicoides midges vector numerous veterinary and human pathogens. Many of these diseases lack effective therapeutic treatments or vaccines to limit transmission. The only effective approach to limit disease transmission is vector control. However, current vector control for Culicoides midges is complicated by the biology of many Culicoides species and is not always effective at reducing midge populations and impacting disease transmission. The endosymbiont Wolbachia pipientis Hertig may offer an alternative control approach to limit disease transmission and affect Culicoides populations. Here the detection of Wolbachia infections in nine species of Culicoides midges is reported. Infections were detected at low densities using qPCR. Wolbachia infections were confirmed with the sequencing of a partial region of the 16S gene. Fluorescence in situ hybridization of Culicoides sonorensis Wirth and Jones adults and dissected ovaries confirm the presence of Wolbachia infections in an important vector of Bluetongue and Epizootic hemorrhagic disease viruses. The presence of Wolbachia in Culicoides populations in the United States suggests the need for further investigation of Wolbachia as a strategy to limit transmission of diseases vectored by Culicoides midges.

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Epidemiological characterization and risk factors associated with lentiviral infection of small ruminants at animal fairs in the semiarid Sertão region of Pernambuco, Brazilian semiarid

Semina Ciências Agrárias ◽

10.5433/1679-0359.2017v38n4p1875 ◽

2017 ◽

Vol 38 (4) ◽

pp. 1875

Author(s):

José Romero Alexandre Alves ◽

Clécio Henrique Limeira ◽

Geilson Manoel de Souza Lima ◽

Raymundo Rizaldo Pinheiro ◽

Francisco Selmo Fernandes Alves ◽

...

Keyword(s):

Risk Factors ◽

Traffic Control ◽

Disease Transmission ◽

Significant Risk ◽

Small Ruminants ◽

Significant Risk Factor ◽

Disease Diagnosis ◽

Serum Samples ◽

Western Blots ◽

Factors Associated

Animal agglomerations at commercial events such as trade fairs represent an important facilitator in infectious disease transmission. Thus, it is crucial to understand the epidemiology of infectious diseases in small ruminants. The objective of this study was to examine lentiviral presence in goats and sheep traded at the animal fair of Tabira city (Sertão region of Pernambuco) and identify possible risk factors associated with infection. We collected serum samples from 233 crossbred goats and 119 crossbred sheep, belonging to 12 breeders, at the Tabira livestock fair from November 2014 to June 2015. An epidemiological questionnaire was used to analyze the risk factors. Agar gel immunodiffusion (AGID) and western blotting (WB) were performed to diagnose small ruminant lentivirus (SRLV) infection. In the AGID test, we used maedi-visna virus (MVV) antigens for sheep and caprine arthritis/encephalitis virus (strain Cork) (CAEV-Co) antigen for goats. The WB analysis used CAEV-Co antigen for both species. Variables from the questionnaire were analyzed with univariate and multivariate statistics. One seropositive goat but no sheep was identified via AGID. According to the WB results, 15/233 goats (6.44%; CI95% = 3.94 - 10.35%) and 8/119 sheep (6.72%; CI95% = 3.45 - 12.71%) were seropositive, totaling 23/352 reactive animals (6.53%; CI95% = 4.39 - 9.61%) from 12 herds. Annual vermifugation of the animals was a significant risk factor (odds ratio = 5.9; CI95% = 1.7-19.8; p = 0.04) for disease in goats, but no variables associated with infection risks were identified in sheep. We concluded that SRLV was present in goats and sheep at the animal fair. Western blots were more sensitive than AGID for SRLV diagnosis. Practices aiming to improve sanitary management may reduce the risk of infection in goats. All studied herds included animals identified as seropositive for SRLV. Therefore, we recommend adopting measures that increase disease diagnosis while intensifying traffic control and surveillance of animal agglomerations.

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ASSESSMENT OF VECTOR CONTROL AND PHARMACEUTICAL TREATMENT IN REDUCING MALARIA BURDEN: A SENSITIVITY AND OPTIMAL CONTROL ANALYSIS

Journal of Biological System ◽

10.1142/s0218339011500331 ◽

2012 ◽

Vol 20 (01) ◽

pp. 67-85 ◽

Cited By ~ 4

Author(s):

ZI SANG ◽

ZHIPENG QIU ◽

QINGKAI KONG ◽

YUN ZOU

Keyword(s):

Optimal Control ◽

Sensitivity Analysis ◽

Vector Control ◽

Disease Transmission ◽

Control Programme ◽

Control Analysis ◽

Optimal Control Strategy ◽

Malaria Burden ◽

Sensitivity Indices ◽

Cost Efficient

Vector control and pharmaceutical treatments are currently the main methods of malaria control. To assess their impacts on disease transmission and prevalence, sensitivity and optimal control analysis are performed respectively on a mathematical malaria model. Comparisons are made between the result of sensitivity analysis and that of optimal control analysis. Numerical simulation shows that optimal control strategy is available and cost-efficient. The simulating results also indicates that vector control is always much more beneficial than other anti-malaria measures in an optimal control programme. This further suggests that the results of sensitivity analysis by calculating sensitivity indices cannot help policy-makers to formulate a more effective optimal control programme.

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The Importance of Subterranean Mosquito Habitat to Arbovirus Vector Control Strategies in North Queensland, Australia

Journal of Medical Entomology ◽

10.1603/0022-2585-37.6.846 ◽

2000 ◽

Vol 37 (6) ◽

pp. 846-853 ◽

Cited By ~ 56

Author(s):

B. H. Kay ◽

P. A. Ryan ◽

B. M. Russell ◽

J. S. Holt ◽

S. A. Lyons ◽

...

Keyword(s):

Vector Control ◽

Control Strategies ◽

Arbovirus Vector

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A systematic review assessing the potential for release of vector species from competition following insecticide-based population suppression of Anopheles species in Africa

Parasites & Vectors ◽

10.1186/s13071-021-04975-0 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Alima Qureshi ◽

John B. Connolly

Keyword(s):

Systematic Review ◽

Species Composition ◽

Vector Control ◽

Disease Transmission ◽

Residual Disease ◽

Convincing Evidence ◽

Qualitative Assessment ◽

Vector Species ◽

Management Approaches ◽

Population Suppression

Abstract Background While insecticide-based vector control can effectively target vector species in areas of high malaria endemicity, such as Anopheles gambiae in Africa, residual disease transmission can occur. Understanding the potential role of competitive displacement between vector species could inform both current insecticide-based vector control programmes and the development of future complementary interventions. Methods A systematic review was conducted to identify published studies of insecticide-based vector control of Anopheles species in Africa that reported indices for absolute densities of vector species. After screening against inclusion, exclusion and risk of bias criteria, studies were assigned to three categories based on whether they showed population density changes involving decreases in two or more vector species (D), increases in two or more vector species (I), or increases in one vector species concomitant with decreases in another vector species (ID). Category ID studies could thus provide evidence consistent with the release of vector species from competition following the insecticide-based population suppression of Anopheles species. Results Of 5569 papers identified in searches, 30 were selected for quantitative and qualitative analysis. Nineteen studies were assigned to category D and one to category I. Ten studies categorised as ID provided evidence ranging from weak to persuasive that release from competition could have contributed to changes in species composition. Category ID showed no statistical differences from category D for reductions in malaria transmission and levels of insecticide resistance, but did so for insecticide type, pyrethroids being associated with category ID. A qualitative assessment identified five studies that provided the most convincing evidence that release from competition could have contributed to changes in species composition. Conclusions This review identified evidence that insecticide-based reductions in the density of Anopheles species in Africa could facilitate the release of other vector species from competition. While it remains uncertain whether this evidence is representative of most entomological sequelae of insecticide-based vector control in the field, five studies provided persuasive evidence that insecticide use could lead, at least under some circumstances, to competitive release of non-targeted vector species. These results should inform current and future integrated vector management approaches to malaria control. Graphical abstract

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Incorporating the mutational landscape of SARS-COV-2 variants and case-dependent vaccination rates into epidemic models

10.1101/2021.11.28.21266882 ◽

2021 ◽

Author(s):

Mohammad Mihrab Chowdhury ◽

Md Rafiul Islam ◽

Md Sakhawat Hossain ◽

Nusrat Tabassum ◽

Angela Peace

Keyword(s):

Disease Transmission ◽

Vaccine Development ◽

Vaccination Rate ◽

Time Varying ◽

Vaccination Rates ◽

Mutational Landscape ◽

Global Pandemic ◽

Effective Manner ◽

Short Period ◽

People’S Attitudes

Coronavirus Disease (COVID-19), which began as a small outbreak in Wuhan, China in December 2019, became a global pandemic within months due to its high transmissibility. In the absence of pharmaceutical treatment, various non-pharmaceutical interventions (NPIs) to contain the spread of COVID-19 brought the entire world to a halt. After almost a year of seemingly returning to normalcy with the world's quickest vaccine development, the advent of more infectious and vaccine-resistant coronavirus variants is bringing the situation back to where it was a year ago. In the light of this new situation, we conducted a study to portray the possible scenarios based on the three key factors: impact of interventions (pharmaceutical and NPIs), vaccination rate, and vaccine efficacy. In our study, we assessed two of the most crucial factors, transmissibility and vaccination rate, in order to reduce the spreading of COVID in a simple but effective manner. In order to incorporate the time-varying mutational landscape of COVID-19 variants, we estimated weighted transmissibility composed of the proportion of existing strains that naturally vary over time. Additionally, we consider time-varying vaccination rates based on the number of daily new cases. Our method for calculating the vaccination rate from past active cases is an effective approach in forecasting probable future scenarios as it actively tracks people's attitudes toward immunization as active cases change. Our simulations show that if a large number of individuals cannot be vaccinated in a short period of time, adopting NPIs is the best approach to manage disease transmission with the emergence of new vaccine breakthrough variants and more infectious variants.

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