Oral susceptibility of aedine and culicine mosquitoes (Diptera: Culicidae) to Batai Orthobunyavirus

Background A number of zoonotic mosquito-borne viruses have emerged in Europe in recent decades. Batai virus (BATV), a member of the genus Orthobunyavirus, is one example of a relatively newly emerged mosquito-borne virus, having been detected in mosquitoes and livestock. We conducted vector competency studies on three mosquito species at a low temperature to assess whether Aedes and Culex mosquito species are susceptible to infection with BATV. Methods Colonised lines of Aedes aegypti and Culex pipiens and a wild-caught species, Aedes detritus, were orally inoculated with BATV strain 53.2, originally isolated from mosquitoes trapped in Germany in 2009. Groups of blood-fed female mosquitoes were maintained at 20 °C for 7 or 14 days. Individual mosquitoes were screened for the presence of BATV in body, leg and saliva samples for evidence of infection, dissemination and transmission, respectively. BATV RNA was detected by reverse transcription-PCR, and positive results confirmed by virus isolation in Vero cells. Results Aedes detritus was highly susceptible to BATV, with an infection prevalence of ≥ 80% at both measurement time points. Disseminated infections were recorded in 30.7–41.6% of Ae. detritus, and evidence of virus transmission with BATV in saliva samples (n = 1, days post-infection: 14) was observed. Relatively lower rates of infection for Ae. aegypti and Cx. pipiens were observed, with no evidence of virus dissemination or transmission at either time point. Conclusions This study shows that Ae. detritus may be a competent vector for BATV at 20 °C, whereas Ae. aegypti and Cx. pipiens were not competent. Critically, the extrinsic incubation period appears to be ≤ 7 days for Ae. detritus, which may increase the onward transmissibility potential of BATV in these populations. Graphical Abstract

Oral susceptibility of aedine and culicine mosquitoes (Diptera: Culicidae) to Batai orthobunyavirus

Background A number of zoonotic mosquito-borne viruses have emerged in Europe in recent decades. Batai virus (BATV), orthobunyavirus, is one example having been detected in mosquitoes and livestock. We conducted vector competency studies on three mosquito species at a low temperature to assess whether Aedes and Culex mosquito species are susceptible to infection with BATV. Methods Colonised lines of Aedes aegypti and Culex pipiens, and a wild-caught species, Aedes detritus, were orally inoculated with BATV strain 53.2, originally isolated from mosquitoes trapped in Germany in 2009. Groups of blood-fed female mosquitoes were maintained at 20oC for seven or fourteen days. Individual mosquitoes were screened for the presence of BATV in body, leg and saliva samples for evidence of infection, dissemination and transmission, respectively. Batai virus RNA was detected by RT-PCR and positive results confirmed by virus isolation in Vero cells. Results Aedes detritus was highly susceptible to BATV with infection prevalence at or above 80% at both time points. Disseminated infections were recorded in 30.7–41.6% of Ae. detritus and evidence for virus transmission with BATV detected in saliva samples (n = 1, dpi = 14) was observed. Lower rates of infection for Ae. aegypti and Cx. pipiens with no evidence for virus dissemination or transmission at either time point. Conclusions This study shows Ae. detritus may be a competent vector for BATV at 20oC, whereas Ae. aegypti and Cx. pipiens were not competent. Critically, the extrinsic incubation period appears to be ≤ 7 days for Ae. detritus, which may increase the onward transmissibility potential of BATV in these populations.

The Molecular Tweezer CLR01 Inhibits Antibody-Resistant Cell-to-Cell Spread of Human Cytomegalovirus

Human cytomegalovirus (HCMV) uses two major ways for virus dissemination: infection by cell-free virus and direct cell-to-cell spread. Neutralizing antibodies can efficiently inhibit infection by cell-free virus but mostly fail to prevent cell-to-cell transmission. Here, we show that the ‘molecular tweezer’ CLR01, a broad-spectrum antiviral agent, is not only highly active against infection with cell-free virus but most remarkably inhibits antibody-resistant direct cell-to-cell spread of HCMV. The inhibition of cell-to-cell spread by CLR01 was not limited to HCMV but was also shown for the alphaherpesviruses herpes simplex viruses 1 and 2 (HSV-1, -2). CLR01 is a rapid acting small molecule that inhibits HCMV entry at the attachment and penetration steps. Electron microscopy of extracellular virus particles indicated damage of the viral envelope by CLR01, which likely impairs the infectivity of virus particles. The rapid inactivation of viral particles by CLR01, the viral envelope as the main target, and the inhibition of virus entry at different stages are presumably the key to inhibition of cell-free virus infection and cell-to-cell spread by CLR01. Importance: While cell-free spread enables the human cytomegalovirus (HCMV) and other herpesviruses to transmit between hosts, direct cell-to-cell spread is thought to be more relevant for in vivo dissemination within infected tissues. Cell-to-cell spread is resistant to neutralizing antibodies, thus contributing to the maintenance of virus infection and virus dissemination in the presence of an intact immune system. Therefore, it would be therapeutically interesting to target this mode of spread in order to treat severe HCMV infections and to prevent dissemination of virus within the infected host. The molecular tweezer CLR01 exhibits broad-spectrum antiviral activity against a number of enveloped viruses and efficiently blocks antibody-resistant cell-to-cell spread of HCMV, thus representing a novel class of small molecules with promising antiviral activity.

Unravelling the Role of Socioeconomic Forces in the Early Stage of COVID-19 Pandemic: A Global Analysis

The COVID-19 pandemic has rapidly evolved into an acute health crisis with extensive socioeconomic and demographic consequences. The severity of the COVID-19 pandemic requires a refined (and more comprehensive) understanding of virus dissemination over space, transmission mechanisms, clinical features, and risk factors. In line with this assumption, the present study illustrates a comparative, empirical analysis of the role of socioeconomic and demographic dimensions in the early stages of the COVID-19 pandemic grounded on a large set of indicators comparing the background context across a global sample of countries. Results indicate that—in addition to epidemiological factors—basic socioeconomic forces significantly shaped contagions as well as hospitalization and death rates across countries. As a response to the global crisis driven by the COVID-19 pandemic, all-embracing access to healthcare services should be strengthened along with the development of sustainable health systems supported by appropriate resources and skills. The empirical findings of this study have direct implications for the coordination of on-going, global efforts aimed at containing COVID-19 (and other, future) pandemics.

Recurrent Dissemination of SARS-CoV-2 Through the Uruguayan–Brazilian Border

Uruguay is one of the few countries in the Americas that successfully contained the coronavirus disease 19 (COVID-19) epidemic during the first half of 2020. Nevertheless, the intensive human mobility across the dry border with Brazil is a major challenge for public health authorities. We aimed to investigate the origin of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strains detected in Uruguayan localities bordering Brazil as well as to measure the viral flux across this ∼1,100 km uninterrupted dry frontier. Using complete SARS-CoV-2 genomes from the Uruguayan–Brazilian bordering region and phylogeographic analyses, we inferred the virus dissemination frequency between Brazil and Uruguay and characterized local outbreak dynamics during the first months (May–July) of the pandemic. Phylogenetic analyses revealed multiple introductions of SARS-CoV-2 Brazilian lineages B.1.1.28 and B.1.1.33 into Uruguayan localities at the bordering region. The most probable sources of viral strains introduced to Uruguay were the Southeast Brazilian region and the state of Rio Grande do Sul. Some of the viral strains introduced in Uruguayan border localities between early May and mid-July were able to locally spread and originated the first outbreaks detected outside the metropolitan region. The viral lineages responsible for Uruguayan urban outbreaks were defined by a set of between four and 11 mutations (synonymous and non-synonymous) with respect to the ancestral B.1.1.28 and B.1.1.33 viruses that arose in Brazil, supporting the notion of a rapid genetic differentiation between SARS-CoV-2 subpopulations spreading in South America. Although Uruguayan borders have remained essentially closed to non-Uruguayan citizens, the inevitable flow of people across the dry border with Brazil allowed the repeated entry of the virus into Uruguay and the subsequent emergence of local outbreaks in Uruguayan border localities. Implementation of coordinated bi-national surveillance systems is crucial to achieve an efficient control of the SARS-CoV-2 spread across this kind of highly permeable borderland regions around the world.

Diagnostic Performance of Ag-RDTs and NAAT for SARS-CoV2 Identification in Symptomatic Patients in Catalonia

The use of rapid antigenic tests (Ag-RDTs) to diagnose a SARS-CoV-2 infection has become a common practice recently. This study aimed to evaluate performance of Abbott PanbioTM Ag-RDTs with regard to nucleic acid amplification testing (NAAT) in the early stages of the disease. A cohort of 149,026 infected symptomatic patients, reported in Catalonia from November 2020 to January 2021, was selected. The positivity rates of the two tests were compared with respect to the dates of symptom onset. Ag-RDTs presented positivity rates of 84% in the transmission phases of the disease and 31% in the pre-symptomatic period, compared to 93% and 91%, respectively, for NAAT. The detection of many false negatives with Ag-RDTs during the pre-symptomatic period demonstrates the risk of virus dissemination with this diagnostic technique if used outside the symptomatic period.

Mitigation of the COVID-19 Virus Pandemic

The mitigation of the COVID-19 pandemic has so far revealed large variations regarding reported infectives and fatalities from different countries and regions. The differential equation models used to simulate virus dissemination and the data gathering of infectives and diseased are however susceptible to a range of observational and cognitive biases. The high initial fatality risk reported may have motivated very radical lockdown mitigation measures. The virus mitigation strategy was also influenced by interlocking contingencies between politicians and media. The effects of the mitigative measures should however be evaluated due to their potential collateral damage to the economy as well as on public health issues not directly related to the pandemic. Lessons learned from combatting the COVID-19 pandemic should be utilized to develop knowledge and contingency preparedness to meet global tragedies and new virus pandemics, including our ability to mitigate observational and cognitive biases and to respect the habitats of wildlife.

Endodontic treatment during the COVID-19 pandemic – perception and behaviour of dental professionals

This study evaluated the impact of COVID-19 on the endodontic treatment routine. It was a cross-sectional study using an online questionnaire applied to endodontists to collect information about practical modifications during endodontic treatment to protect professionals and patients against the COVID-19 outbreak. A total 1105 participants from Brazil participated in the survey. More than 90% of respondents identify the high risk of COVID-19 infection to dentists and the need to change some clinical practices. Most respondents (60.1%) are partially following social isolation. The need for a change in Personal Protective Equipment (PPE) during dental appointments was mentioned by 97.1% of respondents. The use of minimal adequate PPE during the pandemic period was associated with the area of residence and marital status of participants. Only 30% of respondents say they use the minimal adequate PPE. Most respondents will change cavity access preparation to reduce virus dissemination. Other changes in endodontic appointments were described in the survey: greater attention to biosafety measures, duration of dental appointments, and duration of intervals between appointments. Endodontists still need to identify the best arrangement for performing their procedures safely during the COVID-19 pandemic. Specific guidelines require detailed information for each specialty and its procedures.

Public Political Participation in the 2020 Regional Head Election: The Case of Denpasar, Indonesia

Employing a qualitative approach, the present study outlooks the political participation of people in Denpasar, Bali, with regard to the 2020 regional head election in the city during COVID-19 pandemic. Data were garnered through observation and documentation. The findings of this study informed that societies participated in the election with the belief that their interest are accommodated by political parties. Although the election was done during pandemic, the stakeholders carried out strict health protocol of COVID-19 in order to prevent the virus dissemination among societies. Based on the findings, this study suggest that the regional head election has an impact on the relationship between political parties at the regional level and the central level, in which, the central executive board always exercises hegemony towards regional party administrators in providing support recommendations for regional head candidates.