Zika virus (ZIKV) was discovered in 1947 and was thought to lead to relatively mild disease. The recent explosive outbreak of ZIKV in South America has led to widespread concern, with reports of neurological sequelae ranging from Guillain Barre syndrome to microcephaly. ZIKV infection has occurred in areas previously exposed to dengue virus (DENV), a flavivirus closely related to ZIKV. Here we investigated the serological cross-reaction between the two viruses. Plasma immune to DENV showed substantial cross-reaction to ZIKV and was able to drive antibody-dependent enhancement (ADE) of ZIKV infection. Using a panel of human monoclonal antibodies (mAbs) to DENV, we showed that most antibodies that reacted to DENV envelope protein also reacted to ZIKV. Antibodies to linear epitopes, including the immunodominant fusion-loop epitope, were able to bind ZIKV but were unable to neutralize the virus and instead promoted ADE. Our data indicate that immunity to DENV might drive greater ZIKV replication and have clear implications for disease pathogenesis and future vaccine programs for ZIKV and DENV.

/pdf/dengue-virus-sero-cross-reactivity-drives-antibody-dependent-3quf3atqz4.pdf

Dengue virus sero-cross-reactivity drives antibody-dependent enhancement of infection with zika virus

Wolbachia Blocks Currently Circulating Zika Virus Isolates in Brazilian Aedes aegypti Mosquitoes

Zika virus (ZIKV) had remained a relatively obscure flavivirus until a recent series of outbreaks accompanied by unexpectedly severe clinical complications brought this virus into the spotlight as causing an infection of global public health concern. In this review, we discuss the history and epidemiology of ZIKV infection, recent outbreaks in Oceania and the emergence of ZIKV in the Western Hemisphere, newly ascribed complications of ZIKV infection, including Guillain-Barre syndrome and microcephaly, potential interactions between ZIKV and dengue virus, and the prospects for the development of antiviral agents and vaccines.

/pdf/zika-virus-new-clinical-syndromes-and-its-emergence-in-the-2xm33jc27w.pdf

Zika Virus: New Clinical Syndromes and its Emergence in the Western Hemisphere

Arthropod-borne viruses (arboviruses) pose a significant threat to global health, causing human disease with increasing geographic range and severity. The recent availability of the genome sequences of medically important mosquito species has kick-started investigations into the molecular basis of how mosquito vectors control arbovirus infection. Here, we discuss recent findings concerning the role of the mosquito immune system in antiviral defense, interactions between arboviruses and fundamental cellular processes such as apoptosis and autophagy, and arboviral suppression of mosquito defense mechanisms. This knowledge provides insights into co-evolutionary processes between vector and virus and also lays the groundwork for the development of novel arbovirus control strategies that target the mosquito vector.

/pdf/mosquito-immunity-against-arboviruses-1t3mjbla7g.pdf

Mosquito Immunity against Arboviruses

Chikungunya virus (CHIKV) is a rapidly emerging mosquito-borne alphavirus causing millions of infections in the tropical and subtropical regions of the world. CHIKV infection often leads to an acute self-limited febrile illness with debilitating myalgia and arthralgia. A potential long-term complication of CHIKV infection is severe joint pain, which can last for months to years. There are no vaccines or specific therapeutics available to prevent or treat infection. This review describes the critical steps in CHIKV cell entry. We summarize the latest studies on the virus-cell tropism, virus-receptor binding, internalization, membrane fusion and review the molecules and compounds that have been described to interfere with virus cell entry. The aim of the review is to give the reader a state-of-the-art overview on CHIKV cell entry and to provide an outlook on potential new avenues in CHIKV research.

/pdf/early-events-in-chikungunya-virus-infection-from-virus-cell-1mum3i7neq.pdf

Early Events in Chikungunya Virus Infection-From Virus Cell Binding to Membrane Fusion

Arboviral diseases transmitted by mosquitoes such as Dengue, Chikungunya and West Nile are global health issues of growing magnitude. Their dissemination in new areas is triggered by increased mobility of persons, animal reservoirs and vectors. This article describes virological, epidemiological and clinical aspects of Chikungunya, which causes sporadic cases or epidemics, sometimes massive, such as the one spreading in the Americas since December 2013. Chikungunya should be suspected in all travellers presenting with fever, arthralgia and sometimes a rash returning from an endemic area. In the absence of vaccine, individual protection relies on the prevention of mosquito bites.

Weibel Galluzzo C

Papers

Reemergence of Chikungunya virus