Arbovirus Infections

The purpose of this multi-site, factorial randomised, platform trial is to evaluate host-directed therapeutic agents in patients hospitalised with moderate and severe dengue virus infection. Our primary aim is to find safe and affordable therapeutics which prevent disease progression among those at high risk for severe dengue, and improve outcomes for those with established severe disease, thereby also reducing the substantial burden placed on health systems in dengue endemic regions.

Arboviruses (arthropod-borne viruses), are a group of RNA viruses that are transmitted to vertebrate hosts by hematophagous arthropods like mosquitos, ticks, and sandflies. In Italy, arboviruses pose a considerable public health concern because of their potential to infect humans and cause severe emergent or re-emergent diseases. Over the past few decades, arboviruses have already been responsible for epidemic outbreaks in Italy, and travels increase the risk of introducing new species previously confined to tropical and sub-tropical regions. Some arboviral infections, like West Nile Virus (WNV), Toscana Virus (TOSV), Sandfly Fever Sicily Virus (SFSV), Sandfly Fever Naples Virus (SFNV), Usutu Virus (USUV), and tick-borne encephalitis virus (TBEV), are considered endemic in Italy. Others, such as Chikungunya Virus (CHIKV), Dengue Virus (DENV), Zika Virus (ZIKV), Yellow Fever Virus (YFV) and Japanese encephalitis Virus (JEV) are under surveillance since imported infections could lead to local outbreaks and subsequent endemic circulation in Italy. Moreover, the increased global travel and unpredictable climate changes could facilitate the spread of arboviral infections. Adequate diagnostic tests play a crucial role in disease surveillance, identifying potential associations between previous infections and chronic diseases and controlling outbreaks by breaking transmission chains. Furthermore, immunological tests can help predict disease severity in healthy and immunocompromised subjects and identify patients at risk for severe disease during secondary infections. In parallel with direct molecular diagnosis tests, the development of an immunological test capable of determining specific arbovirus T cell response may be useful for diagnostic as well as for epidemiological and investigative purposes. Furthermore, its development provides a set of initial knowledge on which to base the construction of other immunological tests for future emerging viruses, providing tools to counter new epidemic outbreaks. At the same time, the evaluation of immune response is necessary in order to control and contain the spread of these viruses. In conclusion, the present study aims to investigate immunological responses in patients infected with endemic arboviruses circulating in Italy those that could potentially emerging in the future. Molecular tests have a reduced detectability window in biological samples, which is why often they are not useful for making a diagnosis. Serological tests can give cross-reactivity phenomena between some arboviruses, making differential diagnosis difficult and often inconclusive. Objective is to assess sensitivity of immunological assays for arboviruses-specific T Cell Response (ARBOspot) in order to use them in combination with conventional diagnostic methods.

The VIROPREG study is a French prospective multicenter cohort study that aims to assess the impact of viral infections and antiviral treatments received during pregnancy on maternal and child health. The study focuses on both chronic viral infections: human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV)\] and on arbovirus infections. This study aims at investigating the following research questions: * What is the rate of mother-to-child transmission for each virus? * What are the effects of maternal infection on (i) pregnancy outcomes, (ii) the mother's physical and psychological health, and (iii) the fetus' health and development, with a focus on long-term psychomotor development in children born to women living with HIV? * What is the impact of antiretroviral and/or antiviral prophylactic and/or therapeutic treatments administered during pregnancy on maternal and fetal health? Mother-child pairs will be followed from pregnancy through delivery and from birth until the child reaches 7 years of age. Each mother-child pair will be enrolled into one of four cohort groups based on the maternal infection. HIV Cohort: Pregnant women living with HIV who participate in the research will: * Be followed according to the routine care schedule from enrollment to post-natal visit usually scheduled in maternity after delivery (6-8 weeks post-partum) * Participate in additional follow-up by phone call or videoconference at 4- and 7-years post-partum for research purposes * Complete questionnaires at inclusion, delivery, 4- and 7- years postpartum * In case of breastfeeding, receive follow-up care aligned with routine schedules for up to 2 years postpartum, including 2 additional visits specifically for research at 2- and 3- months postpartum. * In selected cases: provide blood, umbilical cord blood, colostrum and breast milk samples during follow-up visits for research purposes (pharmacological and virological analyses). Children born to mothers living with HIV and who participate in the research will: * Be followed according to the routine care schedule from birth until 2 years of age * Participate in additional follow-up by phone call or videoconference, addressed to mothers, at 4- and 7- years of age for research purposes. HBV Cohort: Pregnant HBV-infected women who participate in the research will: * Be followed according to the routine care schedule from enrollment to post-natal visit usually scheduled in maternity after delivery (6- 8 weeks post-partum) * Complete questionnaires at inclusion and delivery * Provide blood samples during follow-up visits for research purposes. Children born to HBV-infected mothers and who participate in the research will: * Be followed according to the routine care schedule from birth to 2 years of age * Participate in additional follow-up for research purposes at 3 months and 18-24 months of age. HCV Cohort: Pregnant HCV-infected women who participate in the research will: * Be followed according to the routine care schedule from enrollment to post-natal visit usually scheduled in maternity after delivery (6 - 8 weeks post-partum) * Complete questionnaires at inclusion and delivery * Provide blood samples during follow-up visits for research purposes. Children born to HCV-infected mothers and who participate in the research will: * Be followed according to the routine care schedule from birth until 2 years of age * Attend additional follow-up visits scheduled at 3 and 9 months of age for research purposes. Arbovirus Cohort: Pregnant women infected with arbovirus who participate in the research will: * Be followed according to the routine care schedule from enrollment to delivery * Participate in additional follow-up for research purposes at 4 years after delivery. * In case of breastfeeding, women will be monitored for research purposes at Day 7 and Day 30 postpartum * Complete questionnaires at inclusion, Day 7-10 from the inclusion, delivery and 4 years after delivery * Provide blood, amniotic fluid, placenta, umbilical cord blood, colostrum and breast milk samples during follow-up visits for research purposes. Children born to mothers infected with arbovirus and who participate in the research will: * Be followed according to the routine care schedule from birth until 2 years of age. * Participate in additional follow-up for research purposes at inclusion, Day 7 and Day 30 after inclusion * Participate in additional follow-up by phone call or videoconference, addressed to mothers, at 4- and 7- years of age for research purposes.

Background: Fiji, an archipelago in the South Pacific comprising 332 islands distributed among 4 health administrative divisions (Central, Western, Eastern, Northern), is particularly vulnerable to the (re-)emergence of arboviruses and respiratory viruses due to its sub-tropical climate, the presence of several mosquito vector species, and connections with many countries in the Pacific, Asia and North America. Over the past decades, the epidemiological landscape of arboviruses has shifted from the sequential circulation of each of the four dengue virus (DENV) serotypes to the emergence of Zika virus (ZIKV) and chikungunya virus (CHIKV), concomitantly to the concurrent circulation of multiple DENV serotypes. The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 2020 significantly challenged Fiji's healthcare system, with the Delta variant alone accounting for approximately 700 deaths, while other respiratory viruses, such as influenza A and B, cause seasonal outbreaks. Despite these threats, comprehensive and up-to-date seroprevalence data remain scarce, limiting the capacity to inform and adapt public health policies. Methods: The cohort study of Arbovirus and other Emerging Virus Infections in Fiji (AEVI-Fiji cohort study) aims to estimate the prevalence of several arboviruses and respiratory viruses, track the evolution of individual immunity, and analyse transmission dynamics of these viruses within the Fijian population. This longitudinal study will span 38 months and will include about 900 willing participants aged six years and older, recruited from at least 210 households randomly selected across the Central Division. Four visits will be conducted 12 months apart in each household. During each visit, participants will complete a questionnaire capturing their demographic characteristics and history of infections with major arboviruses and respiratory viruses and will provide a blood sample for serological analysis. During the whole study period, participants with a suspected acute infection by an arbovirus or respiratory virus will be screened. Discussion: For the first time in Fiji, the AEVI-Fiji cohort study will generate longitudinal data to explore the determinants of both arbovirus and respiratory virus infections. The findings are expected to guide targeted public health strategies and enhance preparedness for future infectious disease threats in Fiji and the broader Oceania region.