Local Disease Outbreaks Research Articles

Social scientific knowledge in times of crisis: What climate change can learn from coronavirus (and vice versa).

"Crisis, by its very nature, requires decisive intervention. However, important questions can be obscured by the very immediacy of the crisis condition. What is the nature of the crisis? How it is defined (and by whom)? And, subsequently, what forms of knowledge are deemed legitimate and authoritative for informing interventions?""

Localized outbreaks of coral disease on Arabian reefs are linked to extreme temperatures and environmental stressors

The Arabian Peninsula borders the hottest reefs in the world, and corals living in these extreme environments can provide insight into the effects of warming on coral health and disease. Here, we examined coral reef health at 17 sites across three regions along the northeastern Arabian Peninsula (Persian Gulf, Strait of Hormuz and Oman Sea) representing a gradient of environmental conditions. The Persian Gulf has extreme seasonal fluctuations in temperature and chronic hypersalinity, whereas the other two regions experience more moderate conditions. Field surveys identified 13 coral diseases including tissue loss diseases of unknown etiology (white syndromes) in Porites, Platygyra, Dipsastraea, Cyphastrea, Acropora and Goniopora; growth anomalies in Porites, Platygyra and Dipsastraea; black band disease in Platygyra, Dipsastraea, Acropora, Echinopora and Pavona; bleached patches in Porites and Goniopora and a disease unique to this region, yellow-banded tissue loss in Porites. The most widespread diseases were Platygyra growth anomalies (52.9% of all surveys), Acropora white syndrome (47.1%) and Porites bleached patches (35.3%). We found a number of diseases not yet reported in this region and found differential disease susceptibility among coral taxa. Disease prevalence was higher on reefs within the Persian Gulf (avg. 2.05%) as compared to reefs within the Strait of Hormuz (0.46%) or Oman Sea (0.25%). A high number of localized disease outbreaks (8 of 17 sites) were found, especially within the Persian Gulf (5 of 8 sites). Across all regions, the majority of variation in disease prevalence (82.2%) was associated with the extreme temperature range experienced by these corals combined with measures of organic pollution and proximity to shore. Thermal stress is known to drive a number of coral diseases, and thus, this region provides a platform to study disease at the edge of corals’ thermal range.

Impact of temporal scales and recurrent mobility patterns on the unfolding of epidemics

Human mobility plays a key role on the transformation of local disease outbreaks into global pandemics. Indeed, the inclusion of population movement into epidemic models has become mandatory for understanding current epidemic episodes as well as designing efficient prevention policies. Following this challenge, here we develop a Markovian framework that enables us to address the impact of recurrent mobility patterns on epidemic onset at different temporal scales. The formalism is validated by comparing its predictions with results from mechanistic simulations. The fair agreement between theory and numerical simulations, enables us to derive an analytical expression for the epidemic threshold, capturing the critical conditions triggering epidemic outbreaks. Finally, by performing an exhaustive analysis of this epidemic threshold, we reveal that the impact of tuning human mobility on the emergence of diseases is strongly affected by the temporal scales associated to both epidemiological and mobility processes.

A genomic approach to inferring kinship reveals limited intergenerational dispersal in the yellow fever mosquito.

Understanding past dispersal and breeding events can provide insight into ecology and evolution and can help inform strategies for conservation and the control of pest species. However, parent–offspring dispersal can be difficult to investigate in rare species and in small pest species such as mosquitoes. Here, we develop a methodology for estimating parent–offspring dispersal from the spatial distribution of close kin, using pairwise kinship estimates derived from genome‐wide single nucleotide polymorphisms (SNPs). SNPs were scored in 162 Aedes aegypti (yellow fever mosquito) collected from eight close‐set, high‐rise apartment buildings in an area of Malaysia with high dengue incidence. We used the SNPs to reconstruct kinship groups across three orders of kinship. We transformed the geographical distances between all kin pairs within each kinship category into axial standard deviations of these distances, then decomposed these into components representing past dispersal events. From these components, we isolated the axial standard deviation of parent–offspring dispersal and estimated neighbourhood area (129 m), median parent–offspring dispersal distance (75 m) and oviposition dispersal radius within a gonotrophic cycle (36 m). We also analysed genetic structure using distance‐based redundancy analysis and linear regression, finding isolation by distance both within and between buildings and estimating neighbourhood size at 268 individuals. These findings indicate the scale required to suppress local outbreaks of arboviral disease and to target releases of modified mosquitoes for mosquito and disease control. Our methodology is readily implementable for studies of other species, including pests and species of conservation significance.

Securing Indo-Pacific health security: Australia’s approach to regional health security

ABSTRACTIn the wake of several prominent disease outbreaks like Ebola and Zika, global health security is once again high on the international agenda. For its part, the Australian government has committed itself to strengthening regional health security. This policy direction – focusing on the Indo-Pacific region – is both consistent with Australia’s traditional foreign policy approach of concentric circles informing strategic priorities, and is therefore understandable, even predictable. But given that local disease outbreaks in remote locations around the world now have the opportunity to travel rapidly internationally, is the adoption of an exclusively regional focus the most sensible one? This article considers the implications of Australia’s new regional health security initiative, its focus and direction. The paper weighs the benefits and drawbacks of Australia’s new programme and considers whether a wider focus is more appropriate for responding to the health threats of the twenty-first century.

Global Health Security Agenda Implementation: A Case for Community Engagement

In today's interconnected world, infectious diseases can spread rapidly within and between countries. The 2014-2016 Ebola epidemic in Guinea, Liberia, and Sierra Leone underscored the inability of countries with limited capacities and weak public health systems to respond effectively to outbreaks. To mitigate future health threats, nations and international organizations launched the Global Health Security Agenda (GHSA) to accelerate compliance with the WHO's International Health Regulations, so as to enhance global protection from infectious disease threats. To advance GHSA's mandate to build capacity to prevent, detect, and respond to infectious diseases, and thereby contain threats at their source, community engagement is needed. This article advocates for community engagement in GHSA implementation, using examples from 3 GHSA action packages. A country's ability to prevent a local disease outbreak from becoming an epidemic often rests with the level of knowledge about the situation and the actions taken at the community level.

Fine grained compositional analysis of Port Everglades Inlet microbiome using high throughput DNA sequencing.

BackgroundSimilar to natural rivers, manmade inlets connect inland runoff to the ocean. Port Everglades Inlet (PEI) is a busy cargo and cruise ship port in South Florida, which can act as a source of pollution to surrounding beaches and offshore coral reefs. Understanding the composition and fluctuations of bacterioplankton communities (“microbiomes”) in major port inlets is important due to potential impacts on surrounding environments. We hypothesize seasonal microbial fluctuations, which were profiled by high throughput 16S rRNA amplicon sequencing and analysis.Methods & ResultsSurface water samples were collected every week for one year. A total of four samples per month, two from each sampling location, were used for statistical analysis creating a high sampling frequency and finer sampling scale than previous inlet microbiome studies. We observed significant differences in community alpha diversity between months and seasons. Analysis of composition of microbiomes (ANCOM) tests were run in QIIME 2 at genus level taxonomic classification to determine which genera were differentially abundant between seasons and months. Beta diversity results yielded significant differences in PEI community composition in regard to month, season, water temperature, and salinity. Analysis of potentially pathogenic genera showed presence of Staphylococcus and Streptococcus. However, statistical analysis indicated that these organisms were not present in significantly high abundances throughout the year or between seasons.DiscussionSignificant differences in alpha diversity were observed when comparing microbial communities with respect to time. This observation stems from the high community evenness and low community richness in August. This indicates that only a few organisms dominated the community during this month. August had lower than average rainfall levels for a wet season, which may have contributed to less runoff, and fewer bacterial groups introduced into the port surface waters. Bacterioplankton beta diversity differed significantly by month, season, water temperature, and salinity. The 2013–2014 dry season (October–April), was warmer and wetter than historical averages. This may have driven significant differences in beta diversity. Increased nitrogen and phosphorous concentrations were observed in these dry season months, possibly creating favorable bacterial growth conditions. Potentially pathogenic genera were present in the PEI. However their relatively low, non-significant abundance levels highlight their relatively low risk for public health concerns. This study represents the first to sample a large port at this sampling scale and sequencing depth. These data can help establish the inlet microbial community baseline and supplement the vital monitoring of local marine and recreational environments, all the more poignant in context of local reef disease outbreaks and worldwide coral reef collapse in wake of a harsh 2014–16 El Niño event.

Natural immunity against capsular group X N. meningitidis following an outbreak in Togo, 2007

BackgroundCapsular group X N. meningitidis (MenX) has emerged as a cause of localized disease outbreaks in sub-Saharan Africa, but the human immune response following exposure to MenX antigens is poorly described. We therefore assessed the natural immunity against MenX in individuals who were living in an area affected by a MenX outbreak during 2007 in Togo, West Africa. During 2009, 300 healthy individuals (100 aged 3–5 years, 100 aged 13–19 years and 100 aged 20–25 years) were included in the study, and serum responses were compared with sera from age-matched controls from the U.K. and Burkina Faso. MethodsMenX serum bactericidal antibody (SBA) was measured using rabbit complement, and antibodies against MenX polysaccharide (XPS) and outer membrane vesicles (XOMVs) were quantified by ELISA. ResultsThe proportion of Togolese individuals with an SBA titer of ≥8 against the MenX strain was 29% (95% confidence interval (CI) 18–41) among those aged 3–5 years, 34% (95% CI 9–60) among those aged 13–19 years and 32% (95% CI 24–40) among those aged 20–25 years. These were significantly higher than observed in the control populations from the U.K (range 13–16%) and Burkina Faso (range 2–6%). ConclusionIn Togolese individuals, the concentration of serum IgG against XPS was higher among the two older age groups as compared to the youngest age group. Antibody concentrations against MenX PS correlated significantly with SBA titers. This supports further development of a MenX PS based conjugate vaccine. Further studies are needed to verify the ability of MenX PS to induce SBA in humans.

Defining the Risk of Zika and Chikungunya Virus Transmission in Human Population Centers of the Eastern United States.

The recent spread of mosquito-transmitted viruses and associated disease to the Americas motivates a new, data-driven evaluation of risk in temperate population centers. Temperate regions are generally expected to pose low risk for significant mosquito-borne disease; however, the spread of the Asian tiger mosquito (Aedes albopictus) across densely populated urban areas has established a new landscape of risk. We use a model informed by field data to assess the conditions likely to facilitate local transmission of chikungunya and Zika viruses from an infected traveler to Ae. albopictus and then to other humans in USA cities with variable human densities and seasonality. Mosquito-borne disease occurs when specific combinations of conditions maximize virus-to-mosquito and mosquito-to-human contact rates. We develop a mathematical model that captures the epidemiology and is informed by current data on vector ecology from urban sites. The model demonstrates that under specific but realistic conditions, fifty-percent of introductions by infectious travelers to a high human, high mosquito density city could initiate local transmission and 10% of the introductions could result in 100 or more people infected. Despite the propensity for Ae. albopictus to bite non-human vertebrates, we also demonstrate that local virus transmission and human outbreaks may occur when vectors feed from humans even just 40% of the time. Inclusion of human behavioral changes and mitigations were not incorporated into the models and would likely reduce predicted infections. This work demonstrates how a conditional series of non-average events can result in local arbovirus transmission and outbreaks of human disease, even in temperate cities.

Molecular identification and phylogenetic analysis of non-cytopathic bovine viral diarrhea virus isolate obtained from a local respiratory outbreak in Northern Turkey

In February 2016, a local respiratory disease outbreak with two fatalities was reported in Samsun, Turkey. A non-cytopathic bovine viral diarrhea virus (ncp-BVDV) was identified from the organ and leucocyte samples of dead juvenile heifers using RT-PCR with specific primers for the NS2/3 gene coding region. The NS2/3 gene of BVDV was sequenced and compared with other published sequences of BVDV. The sequences of our isolate which was named as Samsun TR, had 81–83% nucleotite (nt) identity for BVDV-1. Phylogenetic analysis revealed that Samsun-TR was closely related to LC089875 (Japan), AF526381 (China) and also shared 83% nucleotide(nt) identity with them. The NS2/3 gene sequence of Samsun-TR was deposited in the GenBank database with the accession number of KX428495.

How Did the Zika Virus Outbreak Impact Residency and Fellowship Recruitment in Miami, FL?

BackgroundIn July 2016 South Florida experienced a Zika Virus (ZIKV) outbreak as part of the introduction of the flavivirus in the Americas. At the same time, the National Residency recruiting season was held. The affected area was a mile away from the residency/fellowship training programs of Jackson Memorial Hospital (JMH) and University of Miami Miller School of Medicine (UM). The population at risk for severe ZIKV complications include pregnant women. Many of the applicants were women at reproductive age. The factors influencing residency applicants’ choice of training program have been reported. However, no study has analyzed how a local outbreak with proximity to the area of training affects applicants’ choice of programs.MethodsFollowing the Match 2017, an electronic survey was sent to 2,256 applicants to 19 JMH/UM graduate medical education (GME) programs (15 residency, 4 fellowship programs). We used quantitative and qualitative analyses to explore factors influencing candidates’ decisions, including the ZIKV outbreak.ResultsSurvey response rate was 15% (331/2256). The quantitative analysis identified factors that were Òvery important to applicantsÓ rated 4–5/5 (current resident satisfaction; relationship between faculty and residents; collegiality of current residents; location; quantity and quality of faculty content/mentoring; faculty teaching expertise; diversity of patients; diversity of types of procedures), consistent with prior research In contrast, the presence of ZIKV in MDC was Ònot importantÓ; average score of 1.46/5. 10 respondents said that the presence of ZIKV was ÒVery ImportantÓ; 4 were female, 6 were male; 3/10 said ZIKV made the applicant less likely to accept the interview offer; all ultimately accepted the interview. 100% of respondents were aware that ZIKV was in Miami-Dade county. However, only 6 % (19) of respondents were provided information about ZIKV by their interviewed Program.ConclusionZIKV outbreak was not a significant independent variable affecting likelihood to match at JMH/UM in Miami-Dade County. These results have important implications for the role of local disease outbreaks in affecting recruitment of medical trainees for residency and fellowship programs.Disclosures All authors: No reported disclosures.

Using Spatial Analysis to Inform Community Immunization Strategies.

Introduction:Recent pertussis outbreaks in the United States suggest our response to local disease outbreaks (eg, vaccine-preventable Bordetella pertussis) may benefit from understanding and applying spatial analytical methods that use data from immunization information systems at a subcounty level.Methods:A 2012 study on Denver, CO, residents less than 19 years of age confirmed pertussis cases and immunization information system records were geocoded and aggregated to the census tract (CT) level. An algorithm assessed whether individuals were up-to-date (UTD) for pertussis vaccines. Pearson, Spearman, and Kendall correlations assessed relations between disease incidence and pertussis vaccine coverage. Using spatial analysis software, disease incidence and UTD rates were spatially weighted, and smoothed. Global and local autocorrelations based on univariate Moran’s I spatial autocorrelation statistics evaluated whether a CT’s rate belong to a cluster based on incidence or UTD measures.Results:Overall disease incidence rate was 116.8/100 000. Assessment of pertussis vaccination coverage was available for 90% of the population. Among 134 672 Denver residents less than 19 years old, 103 496 (77%) were UTD for pertussis vaccines. Raw correlation coefficients showed weak relationships between incidence and immunization rates due to the presence of outliers. With geospatial and clustering analysis, estimates and correlation coefficients were improved with statistically significant Moran’s I values for global and local autocorrelations rejecting the null hypothesis that incidence or UTD rates were randomly distributed. With evidence indicating the presence of clusters, smoothed and weighted disease incidence and UTD rates in 144 CTs identified 21 CTs (15%) for potential public health intervention.Conclusions:Correlation of raw disease incidence and vaccine UTD rates in subcounty regions showed limited association, providing limited information for decision making. By assessing for clusters using spatial analysis methods, we identified CTs with higher incidence and lower immunization coverage for targeted public health interventions.

Viral Zoonoses That Fly with Bats: A Review

Emerging infectious diseases are a growing threat to human health and a great challenge for global medical attention systems. Governmental agencies in tropical regions with abundant zoonotic pathogens should implement an active vigilance/monitoring model in bat reservoir populations because of their species richness, abundance and dispersal capabilities. Chiropterans represent approximately 20% of all mammal species, the second largest order in terms of number of species after rodents. Importantly, bats constitute natural reservoirs for potential infection of humans of several infectious disease agents such as Coronavirus, Filovirus, Lyssavirus, Paramyxovirus, and Flavivirus. Local disease outbreaks caused by new pathogens can expand globally as a result of human intrusion on wildlife ecosystems and subsequent dispersion of pathogens facilitated by international travel—for example, what happened in 2003 during the severe acute respiratory syndrome pandemic (SARS). At this time, it is not possible to predict which pathogen will cross the species barrier in the future. Nonetheless, a better understanding of a holistic transmission process could help the design of strategies to prevent and control of future pandemics. In this work, we present a summary of the potential societal (economic and epidemiological) effect of disease outbreaks of virus families associated with bats, and the preventive and control measures that could be anticipated.

Meningococcal disease during the Hajj and Umrah mass gatherings.

The Hajj and Umrah religious mass gatherings hosted by the Kingdom of Saudi Arabia can facilitate the transmission of infectious diseases. The pilgrimages have been associated with a number of local and international outbreaks of meningococcal disease. These include serogroup A disease outbreaks in 1987 and throughout the 1990s and two international serogroup W135 outbreaks in 2000 and 2001. The implementation of strict preventative measures including mandatory quadrivalent meningococcal vaccination and antibiotic chemoprophylaxis for pilgrims from the African meningitis belt has prevented pilgrimage-associated meningococcal outbreaks since 2001. However, the fluid epidemiology of the disease and the possibility of outbreaks caused by serogroups not covered by the vaccine or emerging hyper-virulent strains, mean that the disease remains a serious public health threat during these events. Continuous surveillance of carriage state and the epidemiology of the disease in the Kingdom and globally and the introduction of preventative measures that provide broad and long-lasting immunity and impact carriage are warranted.

Relaxation of risk-sensitive behaviour of prey following disease-induced decline of an apex predator, the Tasmanian devil.

Apex predators structure ecosystems through lethal and non-lethal interactions with prey, and their global decline is causing loss of ecological function. Behavioural changes of prey are some of the most rapid responses to predator decline and may act as an early indicator of cascading effects. The Tasmanian devil (Sarcophilus harrisii), an apex predator, is undergoing progressive and extensive population decline, of more than 90% in long-diseased areas, caused by a novel disease. Time since local disease outbreak correlates with devil population declines and thus predation risk. We used hair traps and giving-up densities (GUDs) in food patches to test whether a major prey species of devils, the arboreal common brushtail possum (Trichosurus vulpecula), is responsive to the changing risk of predation when they forage on the ground. Possums spend more time on the ground, discover food patches faster and forage more to a lower GUD with increasing years since disease outbreak and greater devil population decline. Loss of top-down effects of devils with respect to predation risk was evident at 90% devil population decline, with possum behaviour indistinguishable from a devil-free island. Alternative predators may help to maintain risk-sensitive anti-predator behaviours in possums while devil populations remain low.

An Analysis of the Preventive Behavior and Attitudes of International Travelers from South East Asia; the Kuala Lumpur Airport Survey

Introduction: There has been significant growth in international tourism from South-East Asia. Travel medicine services are still quite limited in this region. Few data exists on the knowledge, attitudes and practices of travelers from South-East Asia regarding the prevention of travel-related health risks. The present study aimed to characterize the travel trends and risk reduction strategies of international travelers departing from a major Malaysian airport. Methods: We conducted a cross-sectional survey among international travelers at the Kuala Lumpur International Airport. A questionnaire recorded data on the demographic profile, travel patterns, travel health protective measures, sources of pre-travel health advice, personal perception of travel-related risk, and barriers to seeking health advice, travel vaccinations and malaria chemoprophylaxis. Results: 36.8% of respondents had sought pre-travel health advice, mostly (64.7%) from their doctor. 23.6% of the travelers had received travel vaccinations. 40% of travelers were uninsured and over 50% did not know how to access medical care overseas. The survey revealed deficiencies in the risk perception of travelers regarding endemic infectious diseases such as malaria, dengue, and rabies. A minority of the travelers reported an intention to avoid unsafe food and water, inform themselves of local disease outbreaks, pack a first-aid kit, and protect themselves from animal and mosquito bites. Conclusions: This study highlights areas of concern in relation to the knowledge and behavior of the travelers surveyed and points to the need for raising public awareness in South-East Asia of the risks associated with international travel and the most efficient means of mitigating those risks. Keywords: Travel Health, Vaccinations, Risk Assessment, Tropical Infection, Chemoprophylaxis, Airport Survey

Political will and international collaborative frameworks in infectious diseases.

SummaryThe last few decades have been marked by a rapid expansion in the world?s population, along with an increasingly dynamic mobility of individuals. This accelerated global inter‐connectedness enabled microorganisms to reach virtually any location worldwide more rapidly and efficiently than ever before, reshaping the global dynamics of pathogens. As a result, a local infectious disease outbreak anywhere in the world may almost instantaneously assume global dimensions, and should therefore be considered a global priority. The history of several infectious diseases illustrates that in addition to prophylactic and therapeutic medical interventions, the interplay of social, economic, and political factors makes a fundamental contribution to the outcome of infectious disease outbreaks. Furthermore, this multi‐ and cross‐disciplinary interconnectedness is a key determinant of the outcome of efforts to eradicate vaccine‐preventable infectious diseases. A combined framework that incorporates teachings provided by previous outbreaks, and integrates medical and biomedical interventions with contributions made by social, economic, and political factors, emerges as vital requirement of successful global public health initiatives.

Reducing the barriers against analytical epidemiological studies in investigations of local foodborne disease outbreaks in Germany – a starter kit for local health authorities

Thousands of infectious food-borne disease outbreaks (FBDO) are reported annually to the European Food Safety Authority within the framework of the zoonoses Directive (2003/99/EC). Most recognised FBDO occur locally following point source exposure, but only few are investigated using analytical epidemiological studies. In Germany, and probably also in other countries of the European Union, this seems to be particularly true for those investigated by local health authorities. Analytical studies, usually cohort studies or case–control studies, are a powerful tool to identify suspect food vehicles. Therefore, from a public health and food safety perspective, their more frequent usage is highly desirable. We have developed a small toolbox consisting of a strategic concept and a simple software tool for data entry and analysis, with the objective to increase the use of analytical studies in the investigation of local point source FBDO in Germany.

Municipal Solid Waste Management in Nainital, Uttarakhand: A Case Study

Well-organized provision of community services and infrastructure are critical issues for local self-governing organization like municipalities in most developing cities of India. Solid waste has turn out to be the main concern. Solid Waste Management (SWM) is expensive and complex system for local self-governing organizations as it is directly concerned with the health, environment and quality of life of the local people. Incorrect waste collection practices and improper solid waste disposal can pose a serious hazard of local disease outbreak, water source pollution and greenhouse gases.

Characterization of size, structure and purity of serogroup X Neisseria meningitidis polysaccharide, and development of an assay for quantification of human antibodies

Serogroup X Neisseria meningitidis (MenX) has recently emerged as a cause of localized disease outbreaks in sub-Saharan Africa. In order to prepare for vaccine development, MenX polysaccharide (MenX PS) was purified by standard methods and analyzed for identity and structure by NMR spectroscopy. This study presents the first full assignment of the structure of the MenX PS using 13C, 1H and 31P NMR spectroscopy and total correlation spectroscopy (TOCSY) and 1H–13C heteronuclear single quantum coherence (HSQC). Molecular size distribution analysis using HPLC–SEC with multi-angle laser light scattering (MALLS) found the single peak of MenX PS to have a weight-average molar mass of 247,000g/mol, slightly higher than a reference preparation of purified serogroup C meningococcal polysaccharide. MenX PS tended to be more thermostable than serogroup A PS. A method for the quantification of MenX PS was developed by use of high performance anion exchange chromatography with pulsed amperometric detection (HPAEC–PAD). A novel and specific ELISA assay for quantification of human anti-MenX PS IgG based on covalent linkage of the MenX PS to functionally modified microtitre plates was developed and found valid for the assessment of the specific antibody concentrations produced in response to MenX vaccination or natural infection. The current work thus provides the necessary background for the development of a MenX PS-based vaccine to prevent meningococcal infection caused by bacteria bearing this capsule.