Zika Virus Infection in Tourists Travelling to Thailand: Case Series Report

Thailand is a popular tourist destination where Zika virus (ZIKV) transmission is currently active. To our knowledge, there are no reports of ZIKV infection imported from Thailand and affecting children. Here, we describe the clinical and microbiological findings in three cases of vector-borne ZIKV infection: An 11-year-old boy, a 2-year-old girl, and her pregnant mother, this last case leading to the prenatal exposure of her second baby to ZIKV in the second trimester of pregnancy. All patients were diagnosed after traveling to Thailand between September 2019 and January 2020. No complications were detected in any patient at follow-up, and the prenatally exposed fetus showed no abnormalities during intensive antenatal health care monitoring. On postnatal study, there were no clinical signs or microbiological findings of mother-to-child ZIKV transmission. ZIKV IgG was initially positive, but seroreversion occurred at 4 months of life. This report describes the clinical and serological evolution of vector-borne ZIKV infection occurring in dengue-naïve tourists returning from Thailand. The World Health Organization currently recommends that pre-travel advice to prevent arbovirus infection should be maintained in travelers to Southeast Asia.

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Preventing Zika virus infection during pregnancy by timing conception seasonally

10.7287/peerj.preprints.1818 ◽

2016 ◽

Author(s):

Micaela E Martinez-Bakker

Keyword(s):

Zika Virus ◽

Fetal Death ◽

Viral Infections ◽

World Health ◽

Zikv Infection ◽

Transmission Season ◽

In Trans ◽

Congenital Microcephaly ◽

Health Organization ◽

Cns Malformations

It has come to light that Zika virus (ZIKV) infection during pregnancy can result in trans-placental transmission to the fetus along with fetal death, congenital microcephaly and/or Central Nervous System (CNS) malformations. There are projected to be > 9, 200, 000 births annually in countries with ongoing ZIKV transmission. In response to the ZIKV threat, the World Health Organization (WHO) is strategically targeting prevention of infection in pregnant women and funding contraception in epidemic regions. I propose that the damaging effects of ZIKV can be reduced by timing pregnancy seasonally to minimize maternal exposure. Like other acute viral infections—including the related flavivirus, dengue virus (DENV)—the transmission of ZIKV is anticipated to be seasonal. By seasonally planning pregnancy, this aspect of pathogen ecology can be leveraged to align sensitive periods of gestation with the low-transmission season.

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Zika Virus and the Water Supply Chain

International Supply Chain Technology Journal ◽

10.20545/isctj.v3i04.96 ◽

2018 ◽

Vol 3 (04) ◽

Author(s):

Chakaela N Turner

Keyword(s):

Zika Virus ◽

Neurological Complications ◽

Subcortical White Matter ◽

World Health ◽

Autoimmune Response ◽

Response Measure ◽

Zikv Infection ◽

The World ◽

Polymerase Chain ◽

Health Organization

Recently, an epidemic broke out in South America, more specifically Brazil, which is harmful to women baring a child. This epidemic originally began in West Africa. This concern is associated with the increased incident of microcephaly in newborns to mothers infected by the virus. An ultrasound performed at 29 weeks of development uncovered microcephaly with calcifications in the fetal mind and placenta (Miaker, 2016). After the mother asked for a termination of the pregnancy, a fetal post-mortem examination was performed. Microcephaly was seen with verging multifocal dystrophic calcifications in the cortex and subcortical white matter, with related cortical dislodging and gentle central irritation. Zika Virus, or ZIKV, was found in the fetal cerebrum tissue on converse transcriptase–polymerase-chain-response measure, with predictable discoveries on electron microscopy. The complete genome of the virus was recuperated from the fetal mind (Miaker, 2016). The outbreak of “Guillian-Barre Syndrome, [a condition in which the immune system attacks the nerves], and Microcephaly, [meaning little cerebrum], have led the World Health Organization to declare a global health emergency. Gangliosides are crucial in brain development, and their expression correlates with neurogenesis, synaptogenesis, synaptic transmission, and cell proliferation. Targeting the autoimmune response to gangliosides may represent an underexploited opportunity to examine the increased incidence of neurological complications related to ZIKV infection” (Anaya et al., 2016). The purpose of this literature review is to determine the effects of the ZIKV on the nervous system in humans and across other species; we will also determine how Gullain-Barre Syndrome, or GBS, and Microcephaly are developed, and a probable cure to ZIKV.

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Exploring miRNAs as the key to understand symptoms induced by ZIKA virus infection through a collaborative database.

10.1101/042382 ◽

2016 ◽

Cited By ~ 1

Author(s):

Victor Pylro ◽

Francislon Oliveira ◽

Daniel Morais ◽

Sara Orellana ◽

Fabiano Pais ◽

...

Keyword(s):

Gene Expression ◽

Zika Virus ◽

Human Gene ◽

Noncoding Rnas ◽

World Health ◽

Translational Repression ◽

Zikv Infection ◽

Small Noncoding Rnas ◽

Congenital Zika Syndrome ◽

Health Organization

In early 2015, a ZIKA Virus (ZIKV) infection outbreak was recognized in northeast Brazil, where concerns over its possible links with infant microcephaly have been discussed. Providing a definitive link between ZIKV infection and birth defects is still a big challenge. MicroRNAs (miRNAs), are small noncoding RNAs that regulating post-transcriptional gene expression by translational repression, and play important roles in viral pathogenesis and brain development. The potential for flavivirus-mediated miRNA signaling dysfunction in brain-tissue develop provides a compelling mechanism underlying perceived linked between ZIKV and microcephaly. Here, we provide novel evidences toward to understand the mechanism in which miRNAs can be linked to the congenital ZIKA syndrome symptoms. Moreover, following World Health Organization (WHO) recommendations, we have assembled a database to help target mechanistic investigations of this possible relationship between ZIKV symptoms and miRNA mediated human gene expression, helping to foster potential targets for therapy.

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Preventing Zika virus infection during pregnancy by timing conception seasonally

10.7287/peerj.preprints.1818v3 ◽

2016 ◽

Author(s):

Micaela E Martinez-Bakker

Keyword(s):

Zika Virus ◽

Fetal Death ◽

Viral Infections ◽

World Health ◽

Zikv Infection ◽

Transmission Season ◽

In Trans ◽

Congenital Microcephaly ◽

Health Organization ◽

Cns Malformations

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Zika Virus-Specific IgY Results Are Therapeutic Following a Lethal Zika Virus Challenge without Inducing Antibody-Dependent Enhancement

Viruses ◽

10.3390/v11030301 ◽

2019 ◽

Vol 11 (3) ◽

pp. 301 ◽

Cited By ~ 2

Author(s):

Kyle O’Donnell ◽

Bernadette Meberg ◽

James Schiltz ◽

Matthew Nilles ◽

David Bradley

Keyword(s):

Zika Virus ◽

Denv Infection ◽

Western Hemisphere ◽

World Health ◽

Zikv Infection ◽

Antibody Dependent Enhancement ◽

Virus Challenge ◽

Health Organization

The Zika virus (ZIKV) is a newly emerged pathogen in the Western hemisphere. It was declared a global health emergency by the World Health Organization in 2016. There have been 223,477 confirmed cases, including 3720 congenital syndrome cases since 2015. ZIKV infection symptoms range from asymptomatic to Gullain–Barré syndrome and extensive neuropathology in infected fetuses. Passive and active vaccines have been unsuccessful in the protection from or the treatment of flaviviral infections due to antibody-dependent enhancement (ADE). ADE causes an increased viral load due to an increased monocyte opsonization by non-neutralizing, low-avidity antibodies from a previous dengue virus (DENV) infection or from a previous exposure to ZIKV. We have previously demonstrated that polyclonal avian IgY generated against whole-killed DENV-2 ameliorates DENV infection in mice while not inducing ADE. This is likely due to the inability of the Fc portion of IgY to bind to mammalian Fc receptors. We have shown here that ZIKV oligoclonal IgY is able to neutralize the virus in vitro and in IFNAR−/− mice. The concentration of ZIKV-specific IgY yielding 50% neutralization (NT50) was 25 µg/mL. The exposure of the ZIKV, prior to culture with ZIKV-specific IgY or 4G2 flavivirus-enveloped IgG, demonstrated that the ZIKV-specific IgY does not induce ADE. ZIKV IgY was protective in vivo when administered following a lethal ZIKV challenge in 3-week-old IFNAR−/− mice. We propose polyclonal ZIKV-specific IgY may provide a viable passive immunotherapy for a ZIKV infection without inducing ADE.

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Zika virus infection as a cause of congenital brain abnormalities and Guillain-Barré syndrome: A living systematic review

F1000Research ◽

10.12688/f1000research.19918.1 ◽

2019 ◽

Vol 8 ◽

pp. 1433 ◽

Cited By ~ 4

Author(s):

Michel Jacques Counotte ◽

Kaspar Walter Meili ◽

Katayoun Taghavi ◽

Guilherme Calvet ◽

James Sejvar ◽

...

Keyword(s):

Systematic Review ◽

Zika Virus ◽

Causal Relation ◽

Case Control ◽

Adverse Outcomes ◽

World Health ◽

Case Control Studies ◽

Zikv Infection ◽

Health Organization ◽

Strength Of Association

Background: The Zika virus (ZIKV) caused a large outbreak in the Americas leading to the declaration of a Public Health Emergency of International Concern in February 2016. A causal relation between infection and adverse congenital outcomes such as microcephaly was declared by the World Health Organization (WHO) informed by a systematic review structured according to a framework of ten dimensions of causality, based on the work of Bradford Hill. Subsequently, the evidence has continued to accumulate, which we incorporate in regular updates of the original work, rendering it a living systematic review. Methods: We present an update of our living systematic review on the causal relation between ZIKV infection and adverse congenital outcomes and between ZIKV and GBS for four dimensions of causality: strength of association, dose-response, specificity, and consistency. We assess the evidence published between January 18, 2017 and July 1, 2019. Results: We found that the strength of association between ZIKV infection and adverse outcomes from case-control studies differs according to whether exposure to ZIKV is assessed in the mother (OR 3.8, 95% CI: 1.7-8.7, I2=19.8%) or the foetus/infant (OR 37.4, 95% CI: 11.0-127.1, I2=0%). In cohort studies, the risk of congenital abnormalities was 3.5 times higher after ZIKV infection (95% CI: 0.9-13.5, I2=0%). The strength of association between ZIKV infection and GBS was higher in studies that enrolled controls from hospital (OR: 55.8, 95% CI: 17.2-181.7, I2=0%) than in studies that enrolled controls at random from the same community or household (OR: 2.0, 95% CI: 0.8-5.4, I2=74.6%). In case-control studies, selection of controls from hospitals could have biased results. Conclusions: The conclusions that ZIKV infection causes adverse congenital outcomes and GBS are reinforced with the evidence published between January 18, 2017 and July 1, 2019.

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From the Field to the Laboratory: Quantifying Outdoor Mosquito Landing Rate to Better Evaluate Topical Repellents

Journal of Medical Entomology ◽

10.1093/jme/tjaa298 ◽

2021 ◽

Author(s):

Mara Moreno-Gómez ◽

Rubén Bueno-Marí ◽

Andrea Drago ◽

Miguel A Miranda

Keyword(s):

World Health ◽

Asian Tiger Mosquito ◽

Personal Protection ◽

Evaluation Standards ◽

Testing Conditions ◽

Vector Borne Diseases ◽

Asian Tiger ◽

The World ◽

Vector Borne ◽

Health Organization

Abstract Vector-borne diseases are a worldwide threat to human health. Often, no vaccines or treatments exist. Thus, personal protection products play an essential role in limiting transmission. The World Health Organization (WHO) arm-in-cage (AIC) test is the most common method for evaluating the efficacy of topical repellents, but it remains unclear whether AIC testing conditions recreate the mosquito landing rates in the field. This study aimed to estimate the landing rate outdoors, in an area of Europe highly infested with the Asian tiger mosquito (Aedes albopictus (Skuse, 1894, Diptera: Culididae)), and to determine how to replicate this rate in the laboratory. To assess the landing rate in the field, 16 individuals were exposed to mosquitoes in a highly infested region of Italy. These field results were then compared to results obtained in the laboratory: 1) in a 30 m3 room where nine volunteers were exposed to different mosquito abundances (ranges: 15–20, 25–30, and 45–50) and 2) in a 0.064 m3 AIC test cage where 10 individuals exposed their arms to 200 mosquitoes (as per WHO requirements). The highest mosquito landing rate in the field was 26.8 landings/min. In the room test, a similar landing rate was achieved using 15–20 mosquitoes (density: 0.50–0.66 mosquitoes/m3) and an exposure time of 3 min. In the AIC test using 200 mosquitoes (density: 3,125 mosquitoes/m3), the landing rate was 229 ± 48 landings/min. This study provides useful reference values that can be employed to design new evaluation standards for topical repellents that better simulate field conditions.

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Azithromycin Reduction to Reach Elimination of Trachoma (ARRET): study protocol for a cluster randomized trial of stopping mass azithromycin distribution for trachoma

BMC Ophthalmology ◽

10.1186/s12886-020-01776-4 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Abdou Amza ◽

Boubacar Kadri ◽

Beido Nassirou ◽

Ahmed M. Arzika ◽

Ariana Austin ◽

...

Keyword(s):

Primary Outcome ◽

Controlled Trial ◽

Clinical Signs ◽

Cluster Randomized Trial ◽

World Health ◽

Baseline Assessment ◽

Randomized Controlled ◽

Registration Number ◽

Cluster Randomized ◽

Health Organization

Abstract Background The World Health Organization (WHO) recommends annual mass azithromycin distribution until districts drop below 5% prevalence of trachomatous inflammation—follicular (TF). Districts with very low TF prevalence may have little or no transmission of the ocular strains of Chlamydia trachomatis that cause trachoma, and additional rounds of mass azithromycin distribution may not be useful. Here, we describe the protocol for a randomized controlled trial designed to evaluate whether mass azithromycin distribution can be stopped prior to the current WHO guidelines. Methods The Azithromycin Reduction to Reach Elimination of Trachoma (ARRET) study is a 1:1 community randomized non-inferiority trial designed to evaluate whether mass azithromycin distribution can be stopped in districts with baseline prevalence of TF under 20%. Communities in Maradi, Niger are randomized after baseline assessment either to continued annual mass azithromycin distribution or stopping annual azithromycin distribution over a 3-year period. We will compare the prevalence of ocular C. trachomatis (primary outcome), TF and other clinical signs of trachoma, and serologic markers of trachoma after 3 years. We hypothesize that stopping annual azithromycin distribution will be non-inferior to continued annual azithromycin distributions for all markers of trachoma prevalence and transmission. Discussion The results of this trial are anticipated to provide potentially guideline-changing evidence for when mass azithromycin distributions can be stopped in low TF prevalence areas. Trial registration number This study is registered at clinicaltrials.gov (NCT04185402). Registered December 4, 2019; prospectively registered pre-results.

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Two Live Attenuated Vaccines against Recent Low–and Highly Pathogenic H7N9 Influenza Viruses Are Safe and Immunogenic in Ferrets

Vaccines ◽

10.3390/vaccines6040074 ◽

2018 ◽

Vol 6 (4) ◽

pp. 74 ◽

Cited By ~ 2

Author(s):

Larisa Rudenko ◽

Irina Kiseleva ◽

Elena Krutikova ◽

Ekaterina Stepanova ◽

Irina Isakova-Sivak ◽

...

Keyword(s):

Clinical Trial ◽

Phase I ◽

Reverse Genetics ◽

Vaccine Candidate ◽

Clinical Signs ◽

Influenza Viruses ◽

Phase I Clinical Trial ◽

World Health ◽

Histological Data ◽

Health Organization

Influenza H7N9 virus is a potentially pandemic subtype to which most people are immunologically naïve. To be better prepared for the potential occurrence of an H7N9 pandemic, in 2017 the World Health Organization recommended developing candidate vaccine viruses from two new H7N9 viruses, A/Guangdong/17SF003/2016 (A/GD) and A/Hong Kong/125/2017 (A/HK). This report describes the development of live attenuated influenza vaccine (LAIV) candidates against A/GD and A/HK viruses and study of their safety and immunogenicity in the ferret model in order to choose the most promising one for a phase I clinical trial. The A/HK-based vaccine candidate (A/17/HK) was developed by classical reassortment in eggs. The A/GD-based vaccine candidate (A/17/GD) was generated by reverse genetics. Ferrets were vaccinated with two doses of LAIV or phosphate-buffered saline. Both H7N9 LAIVs tested were safe for ferrets, as shown by absence of clinical signs, and by virological and histological data; they were immunogenic after a single vaccination. These results provide a compelling argument for further testing of these vaccines in volunteers. Since the A/HK virus represents the cluster that has caused the majority of human cases, and because the A/HK-based LAIV candidate was developed by classical reassortment, this is the preferred candidate for a phase I clinical trial.

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Clinical signs of trachoma are prevalent among Solomon Islanders who have no persistent markers of prior infection with Chlamydia trachomatis

Wellcome Open Research ◽

10.12688/wellcomeopenres.13423.1 ◽

2018 ◽

Vol 3 ◽

pp. 14

Author(s):

Robert Butcher ◽

Oliver Sokana ◽

Kelvin Jack ◽

Leslie Sui ◽

Charles Russell ◽

...

Keyword(s):

Chlamydia Trachomatis ◽

Sexual Debut ◽

Solomon Islands ◽

Clinical Signs ◽

World Health ◽

Direct Result ◽

Policy Makers ◽

The Public ◽

High Prevalence ◽

Health Organization

Background: The low population-prevalence of trachomatous trichiasis and high prevalence of trachomatous inflammation–follicular (TF) provide contradictory estimates of the magnitude of the public health threat from trachoma in the Solomon Islands. Improved characterisation of the biology of trachoma in the region may support policy makers as they decide what interventions are required. Here, age-specific profiles of anti-Pgp3 antibodies and conjunctival scarring were examined to determine whether there is evidence of ongoing transmission and pathology from ocular Chlamydia trachomatis (Ct) infection. Methods: A total of 1511 individuals aged ≥1 year were enrolled from randomly selected households in 13 villages in which >10% of children aged 1–9 years had TF prior to a single round of azithromycin mass drug administration undertaken six months previously. Blood was collected to be screened for antibodies to the Ct antigen Pgp3. Tarsal conjunctival photographs were collected for analysis of scarring severity. Results: Anti-Pgp3 seropositivity was 18% in 1–9 year olds, sharply increasing around the age of sexual debut to reach 69% in those over 25 years. Anti-Pgp3 seropositivity did not increase significantly between the ages of 1–9 years and was not associated with TF (p=0.581) or scarring in children (p=0.472). Conjunctival scars were visible in 13.1% of photographs. Mild (p<0.0001) but not severe (p=0.149) scars increased in prevalence with age. Conclusions: Neither conjunctival scars nor lymphoid follicles were associated with antibodies to Ct, suggesting that they are unlikely to be a direct result of ocular Ct infection. Clinical signs of trachoma were prevalent in this population but were not indicative of the underlying rates of Ct infection. The current World Health Organization guidelines for trachoma elimination indicated that this population should receive intervention with mass distribution of antibiotics, but the data presented here suggest that this may not have been appropriate.

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