Zika virus and the 2016 Olympic Games – Evidence-based projections derived from dengue do not support cancellation

Recommencement of Sport Leagues With Spectators at the Adelaide Oval During the COVID-19 Pandemic: Planning, Experience, and Impact of a Globally Unprecedented Approach

Non-pharmaceutical interventions including physical distancing and restriction on public gatherings were the cornerstone in controlling the COVID-19 pandemic, in the absence of effective vaccines and available treatment options. Many sport mega-events and sport leagues were canceled or indefinitely postponed, leaving stadiums globally empty or converted to be used as part of the COVID-19 response. There were calls for exit strategies to be developed. With the early containment of COVID-19 in South Australia, various restrictions were lifted in a staged and controlled manner, including the reopening of the Adelaide Oval for recommencement of sport leagues with spectator attendance. This involved the collaboration between public health authorities, other governmental agencies, Adelaide Oval Stadium Management Authority, various sporting leagues etc. Recommencement of sport leagues with staged increase in number of attending spectators allowed various measures to be introduced, revisited, and implemented accordingly, demonstrating that a case-by-case risk assessment can be conducted for mega-events during COVID-19, accounting for the epidemiological context at the time. Economic impacts and non-economic benefits of this recommencement were documented. This globally unprecedented, staged and controlled approach in returning spectators to sporting events during the COVID-19 pandemic could inform the reopening strategy of stadiums, recommencement of sport leagues and mega-events all over the world before herd immunity is achieved or in the event of future outbreaks.

Insecticide resistance and genetic structure of Aedes aegypti populations from Rio de Janeiro State, Brazil

Vector control largely relies on neurotoxic chemicals, and insecticide resistance (IR) directly threatens their effectiveness. In some cases, specific alleles cause IR, and knowledge of the genetic diversity and gene flow among mosquito populations is crucial to track their arrival, rise, and spread. Here we evaluated Aedes aegypti populations’ susceptibility status, collected in 2016 from six different municipalities of Rio de Janeiro state (RJ), to temephos, pyriproxyfen, malathion, and deltamethrin. We collected eggs of Ae. aegypti in Campos dos Goytacazes (Cgy), Itaperuna (Ipn), Iguaba Grande (Igg), Itaboraí (Ibr), Mangaratiba (Mgr), and Vassouras (Vsr). We followed the World Health Organization (WHO) guidelines and investigated the degree of susceptibility/resistance of mosquitoes to these insecticides. We used the Rockefeller strain as a susceptible positive control. We genotyped the V1016I and F1534C knockdown resistance (kdr) alleles using qPCR TaqMan SNP genotyping assay. Besides, with the use of Ae. aegypti SNP-chip, we performed genomic population analyses by genotyping more than 15,000 biallelic SNPs in mosquitoes from each population. We added previous data from populations from other countries to evaluate the ancestry of RJ populations.

All RJ Ae. aegypti populations were susceptible to pyriproxyfen and malathion and highly resistant to deltamethrin. The resistance ratios for temephos was below 3,0 in Cgy, Ibr, and Igg populations, representing the lowest rates since IR monitoring started in this Brazilian region. We found the kdr alleles in high frequencies in all populations, partially justifying the observed resistance to pyrethroid. Population genetics analysis showed that Ae. aegypti revealed potential higher migration among some RJ localities and low genetic structure for most of them. Future population genetic studies, together with IR data in Ae aegypti on a broader scale, can help us predict the gene flow within and among the Brazilian States, allowing us to track the dynamics of arrival and changes in the frequency of IR alleles, and providing critical information to improving vector control program.

Monitoring of insecticide resistance (IR) is mandatory for the effectiveness of vector control programs. We investigate six populations of Aedes aegypti regarding their IR status towards insecticides previously or currently in use, their frequency of IR alleles and resistance ratio, their genetic ancestry and structure, and the gene flow. We observed that Ae. aegypti populations from RJ are becoming susceptible to the larvicide organophosphate temephos. The resistance ratios of temephos are lower among populations where gene flow might be occurring. All RJ populations are highly resistant to deltamethrin, partially explained by the high frequency of kdr alleles. Besides, all populations are susceptible to pyriproxyfen’s insect growth regulator and the organophosphate malathion. Population genomic analyses using more than 15,000 SNPs identified three potential genetic clusters within RJ populations, with higher gene flow to and out of the touristic region called Região dos Lagos. IR data, together with knowledge of the genetic structure and gene flow among different mosquito populations, can help with vector control program decisions.

Health preparedness plan for dengue detection during the 2020 summer Olympic and Paralympic games in Tokyo

Background

Participants in mass gathering events are at risk of acquiring imported and locally endemic infectious diseases. The 2014 dengue outbreak in Tokyo gathered attention since it was the first time in 70 years for Japan to experience an autochthonous transmission. Preparation for emerging infectious threats is essential even in places where these outbreaks have been largely unknown. The aim of this study is to identify strategies for early detection and prevention of dengue infection during the 2020 summer Olympics and Paralympics in Tokyo.

Methodology/Principal findings

We modified and adapted the failure mode and effect analysis (FMEA) methodology, generally used in industrial manufacturing, to examine the current controls for dengue detection and assessment. Information on existing controls were obtained from publicly available resources. Our analysis revealed that the national infectious disease control system to detect dengue in Japan is robust. However, in the case of large assemblies of international visitors for special events when the spread of communicable and vector-borne diseases increases, there are three main gaps that could be reinforced. First, cyclical training or a certification program on tropical disease management is warranted for physicians, especially those working in non-infectious disease-designated hospitals or clinics. Second, multi-language communication methods need to be strengthened especially in the health and hospitality sector. Third, owners of accommodations should consider incorporating a formal tropical disease-training program for their staff members and have a contingency plan for infectious disease-suspected travelers.

Conclusions/Significance

Our findings may facilitate physicians and public health officials where new controls would be beneficial for the 2020 summer Olympics and Paralympics. The FMEA framework has the potential to be applied to other infectious diseases, not just dengue.

Dengue is a mosquito-borne disease that is most prevalent among the emerging arboviruses. Most patients recover from dengue without complications, but a small portion of cases may progress to severe dengue which carries a high mortality rate if left untreated. In 2014, a dengue outbreak unexpectedly occurred in Tokyo, which was the first time in 70 years for Japan to experience an autochthonous transmission. Thus, preparation for dengue and other emerging infectious threats is essential even in places where these outbreaks have been largely unknown. Tokyo will be hosting the Olympic and Paralympic games in 2020, and interventions are warranted to mitigate the risks. We modified and adapted the failure mode effect analysis (FMEA) methodology to test the vulnerability and resiliency of the current controls. Although the FMEA methodology is generally used in industrial manufacturing, it has the potential to be utilized for health preparedness for other infectious diseases as well. Our analysis identifies three strategies to reinforce early detection of dengue infection and prevent further transmission during the Olympic and Paralympic Games.

An update on Zika virus infection

The epidemic history of Zika virus began in 2007, with its emergence in Yap Island in the western Pacific, followed in 2013-14 by a larger epidemic in French Polynesia, south Pacific, where the first severe complications and non-vector-borne transmission of the virus were reported. Zika virus emerged in Brazil in 2015 and was declared a national public health emergency after local researchers and physicians reported an increase in microcephaly cases. In 2016, WHO declared the recent cluster of microcephaly cases and other neurological disorders reported in Brazil a global public health emergency. Similar clusters of microcephaly cases were also observed retrospectively in French Polynesia in 2014. In 2015-16, Zika virus continued its spread to cause outbreaks in the Americas and the Pacific, and the first outbreaks were reported in continental USA, Africa, and southeast Asia. Non-vector-borne transmission was confirmed and Zika virus was established as a cause of severe neurological complications in fetuses, neonates, and adults. This Review focuses on important updates and gaps in the knowledge of Zika virus as of early 2017.

Arboviral and other illnesses in travellers returning from Brazil, June 2013 to May 2016: implications for the 2016 Olympic and Paralympic Games

We evaluated EuroTravNet (a GeoSentinel subnetwork) data from June 2013 to May 2016 on 508 ill travellers returning from Brazil, to inform a risk analysis for Europeans visiting the 2016 Olympic and Paralympic Games in Brazil. Few dengue fever cases (n = 3) and no cases of chikungunya were documented during the 2013-15 Brazilian winter months, August and September, the period when the Games will be held. The main diagnoses were dermatological (37%), gastrointestinal (30%), febrile systemic illness (29%) and respiratory (11%).

Navigating the Zika panic

The epidemics of Ebola virus in West Africa and Zika virus in America highlight how viruses can explosively emerge into new territories. These epidemics also exposed how unprepared we are to handle infectious disease emergencies. This is also true when we consider hypothesized new clinical features of infection, such as the associations between Zika virus infection and severe neurological disease, including microcephaly and Guillain-Barré syndrome. On the surface, these pathologies appear to be new features of Zika virus infection, however, causal relationships have not yet been established. Decades of limited Zika virus research are making us scramble to determine the true drivers behind the epidemic, often at the expense of over-speculation without credible evidence. Here we review the literature and find no conclusive evidence at this time for significant biological differences between the American Zika virus strains and those circulating elsewhere. Rather, the epidemic scale in the Americas may be facilitated by an abnormally warm climate, dense human and mosquito populations, and previous exposure to other viruses. Severe disease associated with Zika virus may therefore not be a new trait for the virus, rather it may have been overlooked due to previously small outbreaks. Much of the recent panic regarding Zika virus has been about the Olympics in Brazil. We do not find any substantial evidence that the Olympics will result in a significant number of new Zika virus infections (~10 predicted) or that the Olympics will promote further epidemic spread over what is already expected. The Zika virus epidemic in the Americas is a serious situation and decisions based on solid scientific evidence - not hyped media speculations - are required for effective outbreak response.