Enhancement of Zika Infection by Dengue-Specific Antibodies Does Not Alter the Production of Interleukin 6 in FcγRII-Expressing K562 Cells

Letters to the editor on the Zika virus: a bibliometric analysis

Objective:

To conduct a bibliometric analysis of Letters to the Editor published on the Zika virus from 1952–2018.

Methods:

A PubMed search was conducted using the terms (Zika OR ZIKV). Results were limited to 1952–2018 and Publication Type = Letter. Results were exported to EndNote, and the full text of each Letter examined. Each Letter was assigned to one of five categories: Reader Response, Author Reply, Observation, Case Report, or Research. Additional study parameters included number of authors, number of references, use of graphics, and funding. Citation reports were generated for each category and the entire dataset, producing lists sorted by Times Cited.

Results:

Of 499 Letters, only 15 (3.0%) were published before 2016. In 2016, at the height of the Zika virus epidemic in the Americas, 244 (48.9%) Letters were published, dropping to 145 (29.1%) in 2017 and 95 (19.0%) in 2018. Letters included 149 (29.9%) Reader Responses, 56 (11.2%) Author Replies, 112 (22.4%) Observations, 70 (14.0%) Case Reports, and 112 (22.4%) Research. The Letters were written by 1–35 authors; 369 (74.0%) Letters had 1–5 authors, and 130 (26.0%) had 6 or more. The Letters cited 0–63 references, with an average of 7.0 per Letter. Graphics appeared in 192 (38.5%) Letters, and 77 (15.4%) Letters reported funding. An interesting anomaly was the 104 (20.8%) Letters authored or co-authored by 1 individual.

Conclusion:

Letters to the Editor remain an important component of scientific communication and may serve as a valuable source of clinical and research information.

Ophthalmological Considerations for COVID-19 Vaccination in Patients with Inflammatory Eye Diseases and Autoimmune Disorders

The global impact imposed by the coronavirus disease 2019 (COVID-19) pandemic may be soon alleviated by the introduction and worldwide dissemination of safe and effective vaccines. This expedited timetable for development and approval of COVID-19 vaccines is an unprecedented extraordinary, concerted achievement by the scientific community. With the pending global rollout of vaccines, each with different mechanisms of action, physicians of various specialties will need to identify vulnerable patient groups for special considerations or advice. In this commentary, we analyse the important considerations for COVID-19 vaccines in patients with inflammatory eye diseases. Scrutiny of immunogenicity and adverse effects, particularly antibody-dependent enhancement, would better help in counselling these patients undergoing vaccination. More research on pharmacovigilance would allow for tailored guidelines and personalised management strategies.

Challenges and solutions in the development of vaccines against emerging and neglected infectious diseases

Emerging and emergent infectious diseases (EIDs) represent a significant and growing cause of morbidity and mortality with increased potential for pandemics due to globalization and international trade. Challenges remain to the approach toward vaccine development for EIDs. This Special Feature explores areas related to vaccine development and testing, including unique challenges posed in the developing world. Vaccines against multiple pathogens spanning a number of viral families are explored with respect to past activities through to future commercialization. Cost drivers balanced against clinical need are discussed and unique challenges posed by rare diseases are considered.

In-depth characterization of congenital Zika syndrome in immunocompetent mice: Antibody-dependent enhancement and an antiviral peptide therapy

BACKGROUND

Zika virus (ZIKV) infection during pregnancy may cause major congenital defects, including microcephaly, ocular, articular and muscle abnormalities, which are collectively defined as Congenital Zika Syndrome. Here, we performed an in-depth characterization of the effects of congenital ZIKV infection (CZI) in immunocompetent mice.

METHODS

Pregnant dams were inoculated with ZIKV on embryonic day 5.5 in the presence or absence of a sub-neutralizing dose of a pan-flavivirus monoclonal antibody (4G2) to evaluate the potential role of antibody-dependent enhancement phenomenon (ADE) during short and long outcomes of CZI.

FINDINGS

ZIKV infection induced maternal immune activation (MIA), which was associated with occurrence of foetal abnormalities and death. Therapeutic administration of AH-D antiviral peptide during the early stages of pregnancy prevented ZIKV replication and death of offspring. In the post-natal period, CZI was associated with a decrease in whole brain volume, ophthalmologic abnormalities, changes in testicular morphology, and disruption in bone microarchitecture. Some alterations were enhanced in the presence of 4G2 antibody.

INTERPRETATION

Our results reveal that early maternal ZIKV infection causes several birth defects in immunocompetent mice, which can be potentiated by ADE phenomenon and are associated with MIA. Additionally, antiviral treatment with AH-D peptide may be beneficial during early maternal ZIKV infection. FUND: This work was supported by the Brazilian National Science Council (CNPq, Brazil), Minas Gerais Foundation for Science (FAPEMIG), Funding Authority for Studies and Projects (FINEP), Coordination of Superior Level Staff Improvement (CAPES), National Research Foundation of Singapore and Centre for Precision Biology at Nanyang Technological University.

The possible role of cross-reactive dengue virus antibodies in Zika virus pathogenesis

Zika virus (ZIKV) has been known for decades to circulate in Africa and Asia. However, major complications of a ZIKV infection have recently become apparent for reasons that are still not fully elucidated. One of the hypotheses for the seemingly increased pathogenicity of ZIKV is that cross-reactive dengue antibodies can enhance a ZIKV infection through the principle of antibody-dependent enhancement (ADE). Recently, ADE in ZIKV infection has been studied, but conclusive evidence for the clinical importance of this principle in a ZIKV infection is lacking. Conversely, the widespread circulation of ZIKV in dengue virus (DENV)-endemic regions raises new questions about the potential contribution of ZIKV antibodies to DENV ADE. In this review, we summarize the results of the evidence to date and elaborate on other possible detrimental effects of cross-reactive flavivirus antibodies, both for ZIKV infection and the risk of ZIKV-related congenital anomalies, DENV infection, and dengue hemorrhagic fever.

Control of Acute Arboviral Infection by Natural Killer Cells

The recent explosive pandemic of chikungunya virus (CHIKV) followed by Zika (ZIKV) virus infections occurring throughout many countries represents the most unexpected arrival of arthropod-borne viral diseases in the past 20 years. Transmitted through the bite of Aedes mosquitoes, the clinical picture associated with these acute arbovirus infections, including Dengue (DENV), CHIKV and ZIKV, ranges from classical febrile illness to life-threatening disease. Whereas ZIKV and CHIKV-mediated infections have previously been recognized as relatively benign diseases, in contrast to Dengue fever, recent epidemic events have brought waves of increased morbidity and mortality leading to a serious public health problem. Although the host immune response plays a crucial role in controlling infections, it may also promote viral spread and immunopathology. Here, we review recent developments in our understanding of the immune response, with an emphasis on the early antiviral immune response mediated by natural killer cells and emphasize their Janus-faced effects in the control of arbovirus infection and pathogenesis. Improving our understanding knowledge on of the mechanisms that control viral infection is crucial in the current race against the globalization of arbovirus epidemics.