Does enterovirus 71 urge for effective vaccine control strategies? Challenges and current opinion

Hand, foot, and mouth disease (HFMD) commonly produces herpangina, but fatal neurological complications have been observed in children. Enterovirus 71 (EV-A71) and Coxsackievirus 16 (CV-A16) are the predominant viruses causing HFMD worldwide. With rising concern about HFMD outbreaks, there is a need for an effective vaccine against EV-A71 and CV-A16. Although an inactivated vaccine has been developed against EV-A71 in China, the inability of the inactivated vaccine to confer protection against CV-A16 infection and other HFMD etiological agents, such as CV-A6 and CV-A10, necessitates the exploration of other vaccine platforms. Thus, the antigenic peptide-based vaccines are promising platforms to develop safe and efficacious multivalent vaccines, while the monoclonal antibodies are viable therapeutic and prophylactic agents against HFMD etiological agents. This article reviews the available information related to the antigenic peptides of the etiological agents of HFMD and their neutralizing antibodies that can provide a basis for the design of future therapies against HFMD etiological agents.

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Epitope Peptide Amphiphile-Based Nanofiber as an Effective Vaccine for Viral Infectious Diseases

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.17655 ◽

2020 ◽

Vol 20 (9) ◽

pp. 5329-5332 ◽

Cited By ~ 1

Author(s):

Yu-Gyeong Kim ◽

Yunsu Lee ◽

Jong-Wha Jung ◽

Hyo-Eon Jin

Keyword(s):

Immune Responses ◽

Enterovirus 71 ◽

Foot And Mouth Disease ◽

Effective Vaccine ◽

Epitope Peptide ◽

Serum Samples ◽

Peptide Amphiphile ◽

Force Microscopy ◽

Self Assembling ◽

Atomic Force

Peptide-based vaccines are relatively safe but have weak immune responses even with an adjuvant. In order to overcome the limitations of peptide-based vaccines, we developed peptide amphiphile (PA)-based nanofibers to enhance the immune responses for preventing enterovirus 71 (EV71) infectious disease (i.e., Hand, Foot, and Mouth Disease). PAs are peptides conjugated with fatty acid alkyl chain and able to self-assemble into various structures including high-aspectratio nanofibers. We designed PAs by coupling EV71 virus particle 1 (VP1) epitope peptides and spacer-crosslinker to the N-terminal of long-chain fatty acids (VP1-PA). PAs then self-assembled into nanofibers at physiological pH (pH 7.4). PA nanofibers were characterized by atomic force microscopy (AFM). For the immunization studies, C57BL/6 mice were injected intraperitoneally (i.p.) with recombinant VP1 with adjuvant (alum), VP1 epitope peptide with or without adjuvant, VP1-PA nanofibers with or without adjuvant, and PBS. To assess the immunogenecity of the VP1-PA nanofibers on serum samples from the immunized mice was analyzed by Western blot for the evaluation of VP1-specific IgG. The PA group showed a higher immune response than the peptide group. We expect that self-assembling VP1-PA based nanofibers as an immune stimulator could enhance immune responses effectively against EV71 infection and overcome the limitations of peptide-based vaccine.

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Spatio-Temporal Patterns of Dengue Fever in Cali, Colombia

International Journal of Applied Geospatial Research ◽

10.4018/jagr.2013100104 ◽

2013 ◽

Vol 4 (4) ◽

pp. 58-75 ◽

Cited By ~ 15

Author(s):

Eric Delmelle ◽

Irene Casas ◽

Jorge H. Rojas ◽

Alejandro Varela

Keyword(s):

Dengue Fever ◽

Control Strategies ◽

Effective Means ◽

Virus Transmission ◽

Deep Understanding ◽

Space Time ◽

Effective Vaccine ◽

Analysis Tool ◽

K Function ◽

Spatio Temporal

Dengue fever is an arboviral disease typical of the tropics that can be life-threatening and if not controlled properly may result in an epidemic. The absence of an effective vaccine makes strategies to prevent the virus transmission the most effective means of control. The planning of such strategies, however, is difficult due to the constant movement of individuals and mosquito host (Aedes aegypti). In this paper, the spatial and temporal relations that might exist between infected individuals during a dengue-epidemic year are explored. This research is motivated in that a deep understanding of potential transmission patterns between individuals might lead to a better design and planning of control strategies. A GIS-based Health Exploratory AnaLysis Tool (HELP) is used to compute space-time relationships by means of spatial K-function, kernel density, space-time K-function and linking pairs of cases within significant time and space intervals. Significant clustering was observed at a scale of 50 meters and 750 meters, respectively while temporal significance was determined at two days and five to eight days. While an increase of cases occurs in the months following severe droughts due to an El Niño phenomenon, the location of clusters remains relatively stable. These are observed near areas where potential habitats for the mosquito exist such as storm drains, hard surfaces where water accumulates (e.g., vases, containers), but also in poorer neighborhoods. The results from the spatial analysis provide valuable information for health care managers to take preventive actions at the municipality level.

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Schistosome vaccines: problems, pitfalls and prospects

Emerging Topics in Life Sciences ◽

10.1042/etls20170094 ◽

2017 ◽

Vol 1 (6) ◽

pp. 641-650 ◽

Cited By ~ 1

Author(s):

R. Alan Wilson ◽

Xiao Hong Li ◽

William Castro-Borges

Keyword(s):

Public Health ◽

Vaccine Development ◽

Control Strategies ◽

Laboratory Mouse ◽

Public Health Problem ◽

Effective Vaccine ◽

Important Public Health Problem ◽

Vaccine Candidates ◽

Important Public Health ◽

Vaccine Testing

Human schistosomiasis caused by parasitic flatworms of the genus Schistosoma remains an important public health problem in spite of concerted efforts at control. An effective vaccine would be a useful addition to control strategies that currently rely on chemotherapy, but such a product is not imminent. In this review, likely causes for the lack of progress are first considered. These include the strategies used by worms to evade the immune response, concepts that have misdirected the field, an emphasis on internal antigens, and the use of the laboratory mouse for vaccine testing. On a positive note, recent investigations on self-cure by the rhesus macaque offer the most promising context for vaccine development. The identification of proteins at the parasite–host interface, especially those of the esophageal glands involved in blood processing, has provided an entirely new category of vaccine candidates that merit evaluation.

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SARS-CoV-2 population-based seroprevalence studies in Europe: a scoping review

BMJ Open ◽

10.1136/bmjopen-2020-045425 ◽

2021 ◽

Vol 11 (4) ◽

pp. e045425

Author(s):

Rebecca Grant ◽

Timothée Dub ◽

Xanthi Andrianou ◽

Hanna Nohynek ◽

Annelies Wilder-Smith ◽

...

Keyword(s):

Scoping Review ◽

Control Strategies ◽

Population Based ◽

Clinical Samples ◽

Effective Vaccine ◽

Lombardy Region ◽

High Transmission ◽

Transmission Area ◽

Western Germany ◽

Primary Measure

ObjectivesWe aimed to review SARS-CoV-2 seroprevalence studies conducted in Europe to understand how they may be used to inform ongoing control strategies for COVID-19.DesignScoping review of peer-reviewed publications and manuscripts on preprint servers from January 2020 to 15 September 2020.Primary measureSeroprevalence estimate (and lower and upper CIs). For studies conducted across a country or territory, we used the seroprevalence estimate and the upper and lower CIs and compared them to the total number of reported infections to calculate the ratio of reported to expected infections.ResultsWe identified 23 population-based seroprevalence studies conducted in Europe. Among 12 general population studies, seroprevalence ranged from 0.42% among residual clinical samples in Greece to 13.6% in an area of high transmission in Gangelt, Germany. Of the eight studies in blood donors, seroprevalence ranged from 0.91% in North-Western Germany to 23.3% in a high-transmission area in Lombardy region, Italy. In three studies which recruited individuals through employment, seroprevalence ranged from 0.5% among factory workers in Frankfurt, Germany, to 10.2% among university employees in Milan, Italy. In comparison to nationally reported cases, the extent of infection, as derived from these seroprevalence estimates, is manyfold higher and largely heterogeneous.ConclusionExposure to the virus in Europe has not reached a level of infection that would prevent further circulation of the virus. Effective vaccine candidates are urgently required to deliver the level of immunity in the population.

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Development of a mechanistic dengue simulation model for Guangzhou

Epidemiology and Infection ◽

10.1017/s095026881900030x ◽

2019 ◽

Vol 147 ◽

Author(s):

G. Mincham ◽

K. L. Baldock ◽

H. Rozilawati ◽

C. R. Williams

Keyword(s):

Simulation Model ◽

Control Strategies ◽

Dengue Infection ◽

Management Strategies ◽

Surveillance Data ◽

Effective Vaccine ◽

Dengue Transmission ◽

Dengue Outbreaks ◽

Computer Based ◽

The City

AbstractDengue infection in China has increased dramatically in recent years. Guangdong province (main city Guangzhou) accounted for more than 94% of all dengue cases in the 2014 outbreak. Currently, there is no existing effective vaccine and most efforts of control are focused on the vector itself. This study aimed to evaluate different dengue management strategies in a region where this disease is emerging. This work was done by establishing a dengue simulation model for Guangzhou to enable the testing of control strategies aimed at vector control and vaccination. For that purpose, the computer-based dengue simulation model (DENSiM) together with the Container-Inhabiting Mosquito Simulation Model (CIMSiM) has been used to create a working dengue simulation model for the city of Guangzhou. In order to achieve the best model fit against historical surveillance data, virus introduction scenarios were run and then matched against the actual dengue surveillance data. The simulation model was able to predict retrospective outbreaks with a sensitivity of 0.18 and a specificity of 0.98. This new parameterisation can now be used to evaluate the potential impact of different control strategies on dengue transmission in Guangzhou. The knowledge generated from this research would provide useful information for authorities regarding the historic patterns of dengue outbreaks, as well as the effectiveness of different disease management strategies.

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