Long-term outcomes of patients affected by Guillain-Barré syndrome in Colombia after the Zika virus epidemic.

BACKGROUND: Guillain-Barré Syndrome (GBS) can lead to significant functional impairments, yet little is understood about the recovery phase and long-term consequences for patients in low- and medium-income countries. OBJECTIVE: To evaluate the functional status and identify factors influencing outcomes among patients with GBS in Colombia. METHODS: Telephone interviews were conducted with GBS patients enrolled in the Neuroviruses Emerging in the Americas Study between 2016 and 2020. The investigation encompassed access to health services and functional status assessments, utilizing the modified Rankin Scale (mRS), GBS Disability Score (GDS), Barthel Index (BI), and International Classification of Functioning (ICF). Univariate analysis, principal component analysis, linear discriminant analysis, and linear regression were employed to explore factors influencing functional status. RESULTS: Forty-five patients (mean age = 50[±22] years) with a median time from diagnosis of 28 months (IQR = 9-34) were included. Notably, 22% and 16% of patients did not receive rehabilitation services during the acute episode and post-discharge, respectively. Most patients demonstrated independence in basic daily activities (median BI = 100, IQR = 77.5-100), improvement in disability as the median mRS at follow-up was lower than at onset (1 [IQR = 0-3] vs. 4.5 [IQR = 4-5], p < 0.001), and most were able to walk without assistance (median GDS = 2, IQR = 0-2). A shorter period from disease onset to interview was associated with worse mRS (p = 0.015) and ICF (p = 0.019). Negative outcomes on GDS and ICF were linked to low socioeconomic status, ICF to the severity of weakness at onset, and BI to an older age. CONCLUSIONS: This study underscores that the functional recovery of GBS patients in Colombia is influenced not only by the natural course of the disease but also by socioeconomic factors, emphasizing the crucial role of social determinants of health.

Neurodevelopment in preschool children exposed and unexposed to Zika virus in utero in Nicaragua: a prospective cohort study.

BACKGROUND: Data on long-term neurodevelopmental outcomes of normocephalic children (born with normal head circumference) exposed to Zika virus in utero are scarce. We aimed to compare neurodevelopmental outcomes in normocephalic children up to age 48 months with and without Zika virus exposure in utero. METHODS: In this prospective cohort study, we included infants from two cohorts of normocephalic children born in León and Managua, Nicaragua during the 2016 Zika epidemic. In León, all women pregnant during the two enrolment periods were eligible. In Managua, mother-child pairs were included from three districts in the municipality of Managua: all women who became pregnant before June 15, 2016, and had a due date of Sept 15, 2016 or later were eligible. Infants were serologically classified as Zika virus-exposed or Zika virus-unexposed in utero and were followed up prospectively until age 48 months. At 36 months and 48 months of age, the Mullen Scales of Early Learning (MSEL) assessment was administered. Primary outcomes were MSEL early learning composite (ELC) scores at 30-48 months in León and 36-48 months in Managua. We used an inverse probability weighting generalised estimating equations model to assess the effect of Zika virus exposure on individual MSEL cognitive domain scores and ELC scores, adjusted for maternal education and age, poverty status, and infant sex. FINDINGS: The initial enrolment period for the León cohort was between Jan 31 and April 5, 2017 and the second was between Aug 30, 2017, and Feb 22, 2018. The enrolment period for the Managua cohort was between Oct 24, 2019, and May 5, 2020. 478 mothers (482 infants) from the León cohort and 615 mothers (609 infants) from the Managua cohort were enrolled, of whom 622 children (303 from the León cohort; 319 from the Managua cohort) were included in the final analysis; four children had microcephaly at birth and thus were excluded from analyses, two from each cohort. 33 (11%) of 303 children enrolled in León and 219 (69%) of 319 children enrolled in Managua were exposed to Zika virus in utero. In both cohorts, no significant differences were identified in adjusted mean ELC scores between Zika virus-exposed and unexposed infants at 36 months (between-group difference 1·2 points [95% CI -4·2 to 6·5] in the León cohort; 2·8 [-2·4 to 8·1] in the Managua cohort) or at 48 months (-0·9 [-10·8 to 8·8] in the León cohort; 0·1 [-5·1 to 5·2] in the Managua cohort). No differences in ELC scores between Zika virus-exposed and unexposed infants exceeded 6 points at any time between 30 months and 48 months in León or between 36 months and 48 months in Managua, which was considered clinically significant in other settings. INTERPRETATION: We found no significant differences in neurodevelopmental scores between normocephalic children with in-utero Zika virus exposure and Zika virus-unexposed children at age 36 months or 48 months. These findings are promising, supporting typical neurodevelopment in Zika virus-exposed normocephalic children, although additional follow-up and research is warranted. FUNDING: National Institute of Child Health and Development, National Institute of Allergy and Infectious Diseases, and Fogarty International Center. TRANSLATION: For the Spanish translation of the abstract see Supplementary Materials section.

Prior flavivirus immunity skews the yellow fever vaccine response to cross-reactive antibodies with potential to enhance dengue virus infection.

The yellow fever 17D vaccine (YF17D) is highly effective but is frequently administered to individuals with pre-existing cross-reactive immunity, potentially impacting their immune responses. Here, we investigate the impact of pre-existing flavivirus immunity induced by the tick-borne encephalitis virus (TBEV) vaccine on the response to YF17D vaccination in 250 individuals up to 28 days post-vaccination (pv) and 22 individuals sampled one-year pv. Our findings indicate that previous TBEV vaccination does not affect the early IgM-driven neutralizing response to YF17D. However, pre-vaccination sera enhance YF17D virus infection in vitro via antibody-dependent enhancement (ADE). Following YF17D vaccination, TBEV-pre-vaccinated individuals develop high amounts of cross-reactive IgG antibodies with poor neutralizing capacity. In contrast, TBEV-unvaccinated individuals elicit a non-cross-reacting neutralizing response. Using YF17D envelope protein mutants displaying different epitopes, we identify quaternary dimeric epitopes as the primary target of neutralizing antibodies. Additionally, TBEV-pre-vaccination skews the IgG response towards the pan-flavivirus fusion loop epitope (FLE), capable of mediating ADE of dengue and Zika virus infections in vitro. Together, we propose that YF17D vaccination conceals the FLE in individuals without prior flavivirus exposure but favors a cross-reactive IgG response in TBEV-pre-vaccinated recipients directed to the FLE with potential to enhance dengue virus infection.

Safety and immunogenicity of a purified inactivated Zika virus vaccine candidate in adults primed with a Japanese encephalitis virus or yellow fever virus vaccine in the USA: a phase 1, randomised, double-blind, placebo-controlled clinical trial.

BACKGROUND: Zika virus infection is a threat to at-risk populations, causing major birth defects and serious neurological complications. Development of a safe and efficacious Zika virus vaccine is, therefore, a global health priority. Assessment of heterologous flavivirus vaccination is important given co-circulation of Japanese encephalitis virus and yellow fever virus with Zika virus. We investigated the effect of priming flavivirus naive participants with a licensed flavivirus vaccine on the safety and immunogenicity of a purified inactivated Zika vaccine (ZPIV). METHODS: This phase 1, placebo-controlled, double-blind trial was done at the Walter Reed Army Institute of Research Clinical Trials Center in Silver Spring, MD, USA. Eligible participants were healthy adults aged 18-49 years, with no detectable evidence of previous flavivirus exposure (by infection or vaccination), as measured by a microneutralisation assay. Individuals with serological evidence of HIV, hepatitis B, or hepatitis C infection were excluded, as were pregnant or breastfeeding women. Participants were recruited sequentially into one of three groups (1:1:1) to receive no primer, two doses of intramuscular Japanese encephalitis virus vaccine (IXIARO), or a single dose of subcutaneous yellow fever virus vaccine (YF-VAX). Within each group, participants were randomly assigned (4:1) to receive intramuscular ZPIV or placebo. Priming vaccinations were given 72-96 days before ZPIV. ZPIV was administered either two or three times, at days 0, 28, and 196-234. The primary outcome was occurrence of solicited systemic and local adverse events along with serious adverse events and adverse events of special interest. These data were analysed in all participants receiving at least one dose of ZPIV or placebo. Secondary outcomes included measurement of neutralizing antibody responses following ZPIV vaccination in all volunteers with available post-vaccination data. This trial is registered at ClinicalTrials.gov, NCT02963909. FINDINGS: Between Nov 7, 2016, and Oct 30, 2018, 134 participants were assessed for eligibility. 21 did not meet inclusion criteria, 29 met exclusion criteria, and ten declined to participate. 75 participants were recruited and randomly assigned. 35 (47%) of 75 participants were male and 40 (53%) were female. 25 (33%) of 75 participants identified as Black or African American and 42 (56%) identified as White. These proportions and other baseline characteristics were similar between groups. There were no statistically significant differences in age, gender, race, or BMI between those who did and did not opt into the third dose. All participants received the planned priming IXIARO and YF-VAX vaccinations, but one participant who received YF-VAX dropped out before receipt of the first dose of ZPIV. 50 participants received a third dose of ZPIV or placebo, including 14 flavivirus-naive people, 17 people primed with Japanese encephalitis virus vaccine, and 19 participants primed with yellow fever vaccine. Vaccinations were well tolerated across groups. Pain at the injection site was the only adverse event reported more frequently in participants who received ZPIV than in those who received placebo (39 [65%] of 60 participants, 95% CI 51·6-76·9 who received ZPIV vs three [21·4%] of 14 who received placebo; 4·7-50·8; p=0·006). No patients had an adverse event of special interest or serious adverse event related to study treatment. At day 57, the flavivirus-naive volunteers had an 88% (63·6-98·5, 15 of 17) seroconversion rate (neutralising antibody titre ≥1:10) and geometric mean neutralising antibody titre (GMT) against Zika virus of 100·8 (39·7-255·7). In the Japanese encephalitis vaccine-primed group, the day 57 seroconversion rate was 31·6% (95% CI 12·6-56·6, six of 19) and GMT was 11·8 (6·1-22·8). Participants primed with YF-VAX had a seroconversion rate of 25% (95% CI 8·7-49·1, five of 20) and GMT of 6·6 (5·2-8·4). Humoral immune responses rose substantially following a third dose of ZPIV, with seroconversion rates of 100% (69·2-100; ten of ten), 92·9% (66·1-99·8; 13 of 14), and 60% (32·2-83·7, nine of 15) and GMTs of 511·5 (177·6-1473·6), 174·2 (51·6-587·6), and 79 (19·0-326·8) in the flavivirus naive, Japanese encephalitis vaccine-primed, and yellow fever vaccine-primed groups, respectively. INTERPRETATION: We found ZPIV to be well tolerated in flavivirus naive and primed adults but that immunogenicity varied significantly according to antecedent flavivirus vaccination status. Immune bias towards the flavivirus antigen of initial exposure and the timing of vaccination may have impacted responses. A third ZPIV dose overcame much, but not all, of the discrepancy in immunogenicity. The results of this phase 1 clinical trial have implications for further evaluation of ZPIV's immunisation schedule and use of concomitant vaccinations. FUNDING: Department of Defense, Defense Health Agency; National Institute of Allergy and Infectious Diseases; and Division of Microbiology and Infectious Disease.

Informing COVID-19 Response and Health Equity Agenda: Collection of Public Health Reports Articles on Emerging Viral Epidemics in the United States, 1878-2021.

OBJECTIVE: Public Health Reports (PHR) is the oldest public health journal in the United States and has reported on viral epidemics since the 19th century. We describe the creation and analysis of a collection of historic PHR articles on emerging viral epidemics in the United States to inform public health response to COVID-19 and future epidemics. METHODS: We searched databases from 1878 through 2021 using custom search strings and conducted a manual search for articles published under previously used names for PHR. We evaluated all articles based on inclusion/exclusion criteria and coded the final list for virus/disease, article type, public health emergency preparedness and response capabilities from the Centers for Disease Control and Prevention (CDC), and PubMed citation count. RESULTS: We identified 349 relevant articles including 130 commentaries/reviews/editorials, 79 epidemiologic reports, 75 research articles, and 65 case study/practice articles. The collection focused on influenza (n = 244), COVID-19 (n = 75), dengue (n = 14), and other emerging viruses, such as Zika and Ebola (n = 25). The collection included 48 articles on health disparities/health of various disadvantaged populations, highlighting such disparities as race and ethnicity (n = 22), socioeconomic status (n = 17), and age (n = 15). When we categorized articles by CDC public health emergency preparedness and response capabilities, we found that 207 addressed surveillance and epidemiologic investigation, 36 addressed community preparedness, and 28 addressed medical countermeasure dispensing and administration. The articles addressing surveillance and epidemiologic investigation, nonpharmaceutical interventions, and community preparedness had the most PubMed citations (799, 334, and 308, respectively). CONCLUSIONS: PHR's historic articles on US emerging viral epidemics covered a range of virus/disease types, emergency preparedness and response capabilities, and contribution types and were widely cited in the scholarly literature. This publicly available and continuously updated collection is a valuable resource for pandemic planning and response.

The safety and immunogenicity of two Zika virus mRNA vaccine candidates in healthy flavivirus baseline seropositive and seronegative adults: the results of two randomised, placebo-controlled, dose-ranging, phase 1 clinical trials.

BACKGROUND: Developing a safe and immunogenic vaccine against Zika virus remains an unmet medical need. We did two phase 1 studies that evaluated the safety and immunogenicity of two mRNA-based Zika virus vaccines (mRNA-1325 and mRNA-1893) in adults. METHODS: Two randomised, placebo-controlled, dose-ranging, multicentre, phase 1 trials, one of mRNA-1325 (mRNA-1325 trial) and one of mRNA-1893 (mRNA-1893 trial), were done. For both studies, eligible participants were healthy adults (aged 18-49 years) who were flavivirus seronegative or flavivirus seropositive at baseline. Participants in the mRNA-1325 trial, which was done at three centres in the USA, were randomly assigned centrally (1:4), using a randomisation table, to the placebo group or one of three mRNA-1325 dose groups (10, 25, or 100 µg). All participants received two doses. The mRNA-1325 vaccine encoded the premembrane and envelope E structural proteins (prME) from a Micronesia 2007 Zika virus isolate. Participants in the mRNA-1893 trial, which was done at three centres in the USA and one centre in Puerto Rico, were randomly assigned (1:4) to the placebo group or one of four mRNA-1893 dose groups (10, 30, 100, or 250 µg) using centralised interactive response technology. All participants in the mRNA-1893 trial received dose one on day 1 and then dose two on day 29. The mRNA-1893 vaccine encoded the prME from the RIO-U1 Zika virus isolate. Safety was the primary outcome of each study, which was evaluated in the respective safety populations (mRNA-1325 trial: participants who received at least one dose and provided safety data; mRNA-1893 trial: participants who received at least one dose) and the solicited safety population (mRNA-1893 trial only: received at least 1 dose and contributed solicited adverse reaction data). Endpoints in both trials included solicited adverse reactions within 7 days after vaccination and unsolicited adverse events within 28 days after vaccination. The secondary outcome of both trials was immunogenicity assessed by Zika virus-specific neutralising antibodies (nAbs) in the per-protocol populations in either trial (participants with no major protocol deviations received full dose[s] of assigned dose level within the acceptable time window, had samples drawn within acceptable time window, and had prevaccination and corresponding post-vaccination serum samples for testing). These were descriptive studies, with no formal hypothesis testing in either trial. Both trials are registered with ClinicalTrials.gov, NCT03014089 (mRNA-1325 trial) and NCT04064905 (mRNA-1893 trial). FINDINGS: The mRNA-1325 trial was done from Dec 14, 2016, to Aug 16, 2018. 90 participants were enrolled: 53 (59%) participants were women and 37 (41%) were men; 84 (93%) were White; and 74 (82%) were not Hispanic or Latino. All three dose levels of mRNA-1325 (10, 25, and 100 µg) were generally well tolerated, but the vaccine elicited poor Zika virus-specific nAb responses. At 28 days after dose two, geometric mean titres (GMTs) were highest for mRNA-1325 10 µg (10·3 [95% CI 5·9-18·2]). The mRNA-1893 trial was done from July 23, 2019, to March 22, 2021. 120 participants (70 [58%] women and 50 [42%] men) were enrolled, most participants were White (89 [74%]), and not Hispanic or Latino (91 [76%]). In the mRNA-1893 trial, solicited adverse reactions in participants who received a vaccine were mostly grade 1 or 2 and occurred more frequently at higher dose levels and after dose two. No participants withdrew due to an unsolicited treatment-emergent adverse event and most of these events were not treatment related. On day 57, all evaluated mRNA-1893 dose levels induced robust Zika virus-specific nAb responses, independent of flavivirus serostatus, that persisted until month 13. At day 57 in participants who were flavivirus seronegative, plaque reduction neutralisation titre test nAb GMTs were highest for mRNA-1893 100 µg (454·2 [330·0-619·6]); in participants who were flavivirus seropositive, GMTs were highest for mRNA-1893 10 µg (224·1 [43·5-1153·5]) and mRNA-1893 100 µg (190·5 [19·2-1887·2]). INTERPRETATION: These findings support the continued development of mRNA-1893 against Zika virus, which was well tolerated at all evaluated dose levels and induced strong Zika virus-specific serum nAb responses after two doses, regardless of baseline flavivirus serostatus. FUNDING: Biomedical Advanced Research and Development Authority and Moderna.

Prevalence of microcephaly and Zika virus infection in a pregnancy cohort in Kenya, 2017-2019.

BACKGROUND: Zika virus (ZIKV), first discovered in Uganda in 1947, re-emerged globally in 2013 and was later associated with microcephaly and other birth defects. We determined the incidence of ZIKV infection and its association with adverse pregnancy and fetal outcomes in a pregnancy cohort in Kenya. METHODS: From October 2017 to July 2019, we recruited and followed up women aged ≥ 15 years and ≤ 28 weeks pregnant in three hospitals in coastal Mombasa. Monthly follow-up included risk factor questions and a blood sample collected for ZIKV serology. We collected anthropometric measures (including head circumference), cord blood, venous blood from newborns, and any evidence of birth defects. Microcephaly was defined as a head circumference (HC) < 2 standard deviations (SD) for sex and gestational age. Severe microcephaly was defined as HC < 3 SD for sex and age. We tested sera for anti-ZIKV IgM antibodies using capture enzyme-linked immunosorbent assay (ELISA) and confirmed positives using the plaque reduction neutralization test (PRNT90) for ZIKV and for dengue (DENV) on the samples that were ZIKV neutralizing antibody positive. We collected blood and urine from participants reporting fever or rash for ZIKV testing. RESULTS: Of 2889 pregnant women screened for eligibility, 2312 (80%) were enrolled. Of 1916 recorded deliveries, 1816 (94.6%) were live births and 100 (5.2%) were either stillbirths or spontaneous abortions (< 22 weeks of gestation). Among 1236 newborns with complete anthropometric measures, 11 (0.9%) had microcephaly and 3 (0.2%) had severe microcephaly. A total of 166 (7.2%) participants were positive for anti-ZIKV IgM, 136 of whom became seropositive during follow-up. Among the 166 anti-ZIKV IgM positive, 3 and 18 participants were further seropositive for ZIKV and DENV neutralizing antibodies, respectively. Of these 3 and 18 pregnant women, one and 13 (72.2%) seroconverted with antibodies to ZIKV and DENV, respectively. All 308 samples (serum and urine samples collected during sick visits and samples that were anti-ZIKV IgM positive) tested by RT-PCR were negative for ZIKV. No adverse pregnancy or neonatal outcomes were reported among the three participants with confirmed ZIKV exposure. Among newborns from pregnant women with DENV exposure, four (22.2%) were small for gestational age and one (5.6%) had microcephaly. CONCLUSIONS: The prevalence of severe microcephaly among newborns in coastal Kenya was high relative to published estimates from facility-based studies in Europe and Latin America, but little evidence of ZIKV transmission. There is a need for improved surveillance for microcephaly and other congenital malformations in Kenya.

A systematic review and meta-analysis on the prevalence of stigma in infectious diseases, including COVID-19: a call to action.

Infectious diseases, including COVID-19, are crucial public health issues and may lead to considerable fear among the general public and stigmatization of, and discrimination against, specific populations. This meta-analysis aimed to estimate the pooled prevalence of stigma in infectious disease epidemics. We systematically searched PubMed, PsycINFO, Embase, MEDLINE, Web of Science, and Cochrane databases since inception to June 08, 2021, and reported the prevalence of stigma towards people with infectious diseases including SARS, H1N1, MERS, Zika, Ebola, and COVID-19. A total of 50 eligible articles were included that contributed 51 estimates of prevalence in 92722 participants. The overall pooled prevalence of stigma across all populations was 34% [95% CI: 28-40%], including enacted stigma (36% [95% CI: 28-44%]) and perceived stigma (31% [95% CI: 22-40%]). The prevalence of stigma in patients, community population, and health care workers, was 38% [95% CI: 12- 65%], 36% [95% CI: 28-45%], and 30% [95% CI: 20-40%], respectively. The prevalence of stigma in participants from low- and middle-income countries was 37% [95% CI: 29-45%], which is higher than that from high-income countries (27% [95% CI: 18-36%]) though this difference was not statistically significant. A similar trend of prevalence of stigma was also observed in individuals with lower education (47% [95% CI: 23-71%]) compared to higher education level (33% [95% CI: 23-4%]). These findings indicate that stigma is a significant public health concern, and effective and comprehensive interventions are needed to counteract the damaging effects of the infodemics during infectious disease epidemics, including COVID-19, and reduce infectious disease-related stigma.

Development and Comparison of Dengue Vulnerability Indices Using GIS-Based Multi-Criteria Decision Analysis in Lao PDR and Thailand.

Dengue is a continuous health burden in Laos and Thailand. We assessed and mapped dengue vulnerability in selected provinces of Laos and Thailand using multi-criteria decision approaches. An ecohealth framework was used to develop dengue vulnerability indices (DVIs) that explain links between population, social and physical environments, and health to identify exposure, susceptibility, and adaptive capacity indicators. Three DVIs were constructed using two objective approaches, Shannon's Entropy (SE) and the Water-Associated Disease Index (WADI), and one subjective approach, the Best-Worst Method (BWM). Each DVI was validated by correlating the index score with dengue incidence for each spatial unit (district and subdistrict) over time. A Pearson's correlation coefficient (r) larger than 0.5 and a p-value less than 0.05 implied a good spatial and temporal performance. Spatially, DVIWADI was significantly correlated on average in 19% (4-40%) of districts in Laos (mean r = 0.5) and 27% (15-53%) of subdistricts in Thailand (mean r = 0.85). The DVISE was validated in 22% (12-40%) of districts in Laos and in 13% (3-38%) of subdistricts in Thailand. The DVIBWM was only developed for Laos because of lack of data in Thailand and was significantly associated with dengue incidence on average in 14% (0-28%) of Lao districts. The DVIWADI indicated high vulnerability in urban centers and in areas with plantations and forests. In 2019, high DVIWADI values were observed in sparsely populated areas due to elevated exposure, possibly from changes in climate and land cover, including urbanization, plantations, and dam construction. Of the three indices, DVIWADI was the most suitable vulnerability index for the study area. The DVIWADI can also be applied to other water-associated diseases, such as Zika and chikungunya, to highlight priority areas for further investigation and as a tool for prevention and interventions.

Zika virus outbreak in Brazil under current and future climate.

INTRODUCTION: Zika virus (ZIKV) is primarily transmitted byAedes aegypti and Aedes albopictus mosquitoes between humans and non-human primates. Climate change may enhance virus reproduction in Aedes spp. mosquito populations, resulting in intensified ZIKV outbreaks. The study objective was to explore how an outbreak similar to the 2016 ZIKV outbreak in Brazil might unfold with projected climate change. METHODS: A compartmental infectious disease model that included compartments for humans and mosquitoes was developed to fit the 2016 ZIKV outbreak data from Brazil using least squares optimization. To explore the impact of climate change, published polynomial relationships between temperature and temperature-sensitive mosquito population and virus transmission parameters (mosquito mortality, development rate, and ZIKV extrinsic incubation period) were used. Projections for future outbreaks were obtained by simulating transmission with effects of projected average monthly temperatures on temperature-sensitive model parameters at each of three future time periods: 2011-2040, 2041-2070, and 2071-2100. The projected future climate was obtained from an ensemble of regional climate models (RCMs) obtained from the Co-Ordinated Regional Downscaling Experiment (CORDEX) that used Representative Concentration Pathways (RCP) with two radiative forcing values, RCP4.5 and RCP8.5. A sensitivity analysis was performed to explore the impact of temperature-dependent parameters on the model outcomes. RESULTS: Climate change scenarios impacted the model outcomes, including the peak clinical case incidence, cumulative clinical case incidence, time to peak incidence, and the duration of the ZIKV outbreak. Comparing 2070-2100 to 2016, using RCP4.5, the peak incidence was 22,030 compared to 10,473; the time to epidemic peak was 12 compared to 9 weeks, and the outbreak duration was 52 compared to 41 weeks. Comparing 2070-2100 to 2016, using RCP8.5, the peak incidence was 21,786 compared to 10,473; the time to epidemic peak was 11 compared to 9 weeks, and the outbreak duration was 50 compared to 41weeks. The increases are due to optimal climate conditions for mosquitoes, with the mean temperature reaching 28 °C in the warmest months. Under a high emission scenario (RCP8.5), mean temperatures extend above optimal for mosquito survival in the warmest months. CONCLUSION: Outbreaks of ZIKV in locations similar to Brazil are expected to be more intense with a warming climate. As climate change impacts are becoming increasingly apparent on human health, it is important to quantify the effect and use this knowledge to inform decisions on prevention and control strategies.

Complications and Sequelae in Patients With Congenital Microcephaly Associated With Zika Virus Infection: Two-Year Follow-Up.

BACKGROUND: We aim to describe the long term follow-up of a cohort of children exposed in utero to the Zika virus. METHODS: Descriptive study of a cohort of microcephalic children due to Zika virus. Logistic regression was used to evaluate variables associated with worse prognosis epilepsy. RESULTS: We followed 28 children (15 females), with a median follow-up of 24 months (IQR = 12-28). During the follow-up, 1 infant died. The median head circumference at birth was 29 cm (IQR = 27-31). All presented a global developmental delay. The most frequent central nervous system abnormalities were on cortical development in 22 participants; dysgenesis of corpus callosum in 13; ventriculomegaly in 25; and calcifications in 24. A total of 9 presented ocular abnormalities, 4 auditory impairment. During follow-up, 12 presented with sleep disorders, 10 with irritability, and 23 with epilepsy (2 with generalized tonic-clonic, 3 with generalized tonic-clonic and spasms, 12 with spasms, 3 tonic and spasms, and 3 motor focal and spasms). The median age at the begin of the epilepsy was 4 months (IQR = 2-10), the median number of drugs used to control the epilepsy was 2 (IQR = 2-3). Maternal illicit drug use during pregnancy was associated with worse prognosis epilepsy (Lennox-Gastaut syndrome, West syndrome, or status epilepticus). A total of 19 presented with dysphagia, 10 children required gastrostomy. CONCLUSION: Children with microcephaly due to Zika virus presented with several complications during follow-up, as epilepsy, spastic diplegia, and global developmental delay.

Cohort profile: Study on Zika virus infection in Brazil (ZIKABRA study).

Zika virus (ZIKV) has been detected in blood, urine, semen, cerebral spinal fluid, saliva, amniotic fluid, and breast milk. In most ZIKV infected individuals, the virus is detected in the blood to one week after the onset of symptoms and has been found to persist longer in urine and semen. To better understand virus dynamics, a prospective cohort study was conducted in Brazil to assess the presence and duration of ZIKV and related markers (viral RNA, antibodies, T cell response, and innate immunity) in blood, semen, saliva, urine, vaginal secretions/menstrual blood, rectal swab and sweat. The objective of the current manuscript is to describe the cohort, including an overview of the collected data and a description of the baseline characteristics of the participants. Men and women ≥ 18 years with acute illness and their symptomatic and asymptomatic household contacts with positive reverse transcriptase-polymerase chain reaction test for ZIKV in blood and/or urine were included. All participants were followed up for 12 months. From July 2017 to June 2019, a total of 786 participants (284 men, 502 women) were screened. Of these, 260 (33.1%) were enrolled in the study; index cases: 64 men (24.6%), 162 (62.3%) women; household contacts: 12 men (4.6%), 22 (8.5%) women. There was a statistically significant difference in age and sex between enrolled and not enrolled participants (p<0.005). Baseline sociodemographic and medical data were collected at enrollment from all participants. The median and interquartile range (IQR) age was 35 (IQR; 25.3, 43) for men and 36.5 years (IQR; 28, 47) for women. Following rash, which was one of the inclusion criteria for index cases, the most reported symptoms in the enrollment visit since the onset of the disease were fever, itching, arthralgia with or without edema, non-purulent conjunctivitis, headache, and myalgia. Ten hospitalizations were reported by eight patients (two patients were hospitalized twice) during follow up, after a median of 108 days following symptom onset (range 7 to 266 days) and with a median of 1.5 days (range 1 to 20 days) of hospital stay. A total of 4,137 visits were performed, 223 (85.8%) participants have attended all visits and 37 (14.2%) patients were discontinued.

Broad-Spectrum Antiviral Activity of 3'-Deoxy-3'-Fluoroadenosine against Emerging Flaviviruses.

Emerging flaviviruses are causative agents of severe and life-threatening diseases, against which no approved therapies are available. Among the nucleoside analogues, which represent a promising group of potentially therapeutic compounds, fluorine-substituted nucleosides are characterized by unique structural and functional properties. Despite having first been synthesized almost 5 decades ago, they still offer new therapeutic opportunities as inhibitors of essential viral or cellular enzymes active in nucleic acid replication/transcription or nucleoside/nucleotide metabolism. Here, we report evaluation of the antiflaviviral activity of 28 nucleoside analogues, each modified with a fluoro substituent at different positions of the ribose ring and/or heterocyclic nucleobase. Our antiviral screening revealed that 3'-deoxy-3'-fluoroadenosine exerted a low-micromolar antiviral effect against tick-borne encephalitis virus (TBEV), Zika virus, and West Nile virus (WNV) (EC50 values from 1.1 ± 0.1 µM to 4.7 ± 1.5 µM), which was manifested in host cell lines of neural and extraneural origin. The compound did not display any measurable cytotoxicity up to concentrations of 25 µM but had an observable cytostatic effect, resulting in suppression of cell proliferation at concentrations of >12.5 µM. Novel approaches based on quantitative phase imaging using holographic microscopy were developed for advanced characterization of antiviral and cytotoxic profiles of 3'-deoxy-3'-fluoroadenosine in vitro In addition to its antiviral activity in cell cultures, 3'-deoxy-3'-fluoroadenosine was active in vivo in mouse models of TBEV and WNV infection. Our results demonstrate that fluoro-modified nucleosides represent a group of bioactive molecules with excellent potential to serve as prospective broad-spectrum antivirals in antiviral research and drug development.

Zika virus transmission by Brazilian Aedes aegypti and Aedes albopictus is virus dose and temperature-dependent.

BACKGROUND: Zika virus (ZIKV) emerged in the Pacific Ocean and subsequently caused a dramatic Pan-American epidemic after its first appearance in the Northeast region of Brazil in 2015. The virus is transmitted by Aedes mosquitoes. We evaluated the role of temperature and infectious doses of ZIKV in vector competence of Brazilian populations of Ae. aegypti and Ae. albopictus. METHODOLOGY/PRINCIPAL FINDINGS: Two Ae. aegypti (Rio de Janeiro and Natal) and two Ae. albopictus (Rio de Janeiro and Manaus) populations were orally challenged with five viral doses (102 to 106 PFU / ml) of a ZIKV strain (Asian genotype) isolated in Northeastern Brazil, and incubated for 14 and 21 days in temperatures mimicking the spring-summer (28°C) and winter-autumn (22°C) mean values in Brazil. Detection of viral particles in the body, head and saliva samples was done by plaque assays in cell culture for determining the infection, dissemination and transmission rates, respectively. Compared with 28°C, at 22°C, transmission rates were significantly lower for both Ae. aegypti populations, and Ae. albopictus were not able to transmit the virus. Ae. albopictus showed low transmission rates even when challenged with the highest viral dose, while both Ae. aegypti populations presented higher of infection, dissemination and transmission rates than Ae. albopictus. Ae. aegypti showed higher transmission efficiency when taking virus doses of 105 and 106 PFU/mL following incubation at 28°C; both Ae. aegypti and Ae. albopictus were unable to transmit ZIKV with virus doses of 102 and 103 PFU/mL, regardless the incubation temperature. CONCLUSIONS/SIGNIFICANCE: The ingested viral dose and incubation temperature were significant predictors of the proportion of mosquito's biting becoming infectious. Ae. aegypti and Ae. albopictus have the ability to transmit ZIKV when incubated at 28°C. However Brazilian populations of Ae. aegypti exhibit a much higher transmission potential for ZIKV than Ae. albopictus regardless the combination of infection dose and incubation temperature.

Association Between Antenatal Exposure to Zika Virus and Anatomical and Neurodevelopmental Abnormalities in Children.

Importance: Zika virus (ZIKV) is a mosquito-borne flavivirus recognized as teratogenic since the 2015 to 2016 epidemic. Antenatal ZIKV exposure causes brain anomalies, yet the full spectrum has not been delineated. Objective: To characterize the clinical features of ZIKV infection at a pediatric referral center in Rio de Janeiro, Brazil, among children with antenatal ZIKV exposure. Design, Setting, and Participants: Retrospective cohort study conducted from May to July 2019 of a prospective cohort of 296 infants with antenatal ZIKV exposure followed up since December 2015 at a tertiary maternity-pediatric hospital. Exposures: Zika virus infection during pregnancy. Main Outcomes and Measures: Characterization of clinical features with anthropometric, neurologic, cardiologic, ophthalmologic, audiometric, and neuroimaging evaluations in infancy and neurodevelopmental assessments (Bayley Scales of Infant and Toddler Development, Third Edition) from 6 to 42 months of age, stratified by head circumference at birth (head circumference within the reference range, or normocephaly [NC] vs microcephaly [MC]). Results: Antenatal exposure to ZIKV was confirmed for 219 of 296 children (74.0%) referred to Instituto Fernandes Figueira with suspected ZIKV infection through positive maternal or neonatal polymerase chain reaction analysis or IgM serology results. Of these children, 110 (50.2%) were boys, ages ranged from 0 to 4 years, and 53 (24.2%) had congenital microcephaly. The anomalies observed in ZIKV-exposed children with MC or NC were failure to thrive (MC: 38 of 53 [71.7%]; NC: 73 of 143 [51.0%]), cardiac malformations (MC: 19 of 46 [41.3%]; NC: 20 of 100 [20.0%]), excess nuchal skin (MC: 16 of 22 [72.7%]; NC: 35 of 93 [37.6%]), auditory abnormalities (MC: 13 of 50 [26.0%]; NC: 14 of 141 [9.9%]), and eye abnormalities (MC: 42 of 53 [79.2%]; NC: 28 of 158 [17.7%]). Although they experienced fewer neurologic abnormalities than children born with MC, those with NC also had frequent neurologic abnormalities (109 of 160 [68.1%]), including hyperreflexia (36 of 136 [26.5%]), abnormal tone (53 of 137 [38.7%]), congenital neuromotor signs (39 of 93 [41.9%]), feeding difficulties (15 of 143 [10.5%]), and abnormal brain imaging results (44 of 150 [29.3%]). Among 112 children with NC with Bayley-III evaluations, 72 (64.3%) had average or above-average scores; 30 (26.8%) scored 1 SD below average in at least 1 domain; and 10 (8.9%) scored 2 SD below average in at least 1 domain. Among 112 children with NC, a smaller head circumference at birth was significantly associated with subsequent below-average cognitive scores (U = 499.5; z = -2.833; P = .004) and language scores (U = 235.5; z = -2.491; P = .01). Conclusions and Relevance: Children without MC who were exposed to ZIKV in utero had a high frequency of anatomical and neurodevelopmental abnormalities. The head circumference at birth for children with NC was associated with neurocognitive development. Recognition of the wide spectrum of clinical phenotypes is critical to ensure early referral to rehabilitative interventions.

Detection of coinfection with Chikungunya virus and Dengue virus serotype 2 in serum samples of patients in State of Tocantins, Brazil.

BACKGROUND: The co-circulation of Chikungunya (CHIKV), Dengue (DENV) and Zika (ZIKV) viruses increased the risk of outbreaks and coinfections among them. Here, we report cases of coinfection in clinical samples from state of Tocantins, Brazil. METHODS: In 2017, the Central Public Health Laboratory (LACEN) received samples of patients who consulted health units with symptoms compatible with arboviral infections. A total of 102 samples were sent to the Retrovirology Laboratory at the Federal University of São Paulo, where they were tested by RT-qPCR to confirm DENV, ZIKV and CHIKV infections and to detect coinfected patients. RESULTS: We identified with CHIKV monoinfection (52), DENV serotypes 1 (28) and serotypes 2 (22). We did not detect ZIKV. Five patients were characterized with coinfection involving CHIKV and DENV serotype 2. CONCLUSIONS: The presence of co-circulating arboviruses increases the chance of coinfection and demonstrates the importance of differential diagnosis and vector control.

Characteristics of Zika virus infection among international travelers: A prospective study from a Spanish referral unit.

BACKGROUND: From the first Zika virus (ZIKV) description, it has progressively widespread worldwide. We analyzed demographic, clinical, microbiologic and travel-related characteristic from returned patients from a ZIKV endemic country in a referral Tropical Medicine Unit. METHOD: A prospective cohort study performed in a Spanish referral center with the aim of determining the significant factors associated with confirmed Zika virus (ZIKV) infection. RESULTS: 817 patients, (56% women, median age 36 [IQR, Interquartile Range: 32-42]) were enrolled. Most had returned from Latin America (n = 486; 59.4%), travelled for tourism (n = 404; 49.4%) and stayed a median of 18 days (IQR: 10-30). 602 (73.6%) presented symptoms, but only 25 (4%) were finally diagnosed with confirmed ZIKV infection (including two pregnant women, without adverse fetal outcomes), 88% (n:22) presented with fever and 92% (n:23) with rash. 56% (n:14) arthralgia and/or myalgia and 28% (n:7) conjunctivitis. The presence of conjunctivitis, fever and rash were associated with an 8.9 (95% CI: 2.2-34.9), 6.4 (95% CI: 1.2-33.3) and 72.3 (95% CI: 9.2-563.5) times greater probability of confirmed ZIKV infection, respectively. CONCLUSION: Travel characteristics and clinical presentation may help clinicians to optimize requests for microbiological testing. Diagnosis of arboviriasis in travellers arriving form endemic areas remains a challenge for clinicians, but must be detected for the possible transmission outside endemic areas, where the vector is present.

Long-Term Protection of Rhesus Macaques from Zika Virus Reinfection.

By the end of the 2016 Zika virus (ZIKV) outbreak, it is estimated that there were up to 100 million infections in the Americas. In approximately one in seven infants born to mothers infected during pregnancy, ZIKV has been linked to microcephaly, developmental delays, or other congenital disorders collectively known as congenital Zika syndrome, as well as Guillain-Barré syndrome, in ZIKV-infected adults. It is a global health priority to develop a vaccine against ZIKV that elicits long-lasting immunity; however, the durability of immunity to ZIKV is unknown. Previous studies in mice and nonhuman primates have been crucial in vaccine development but have not defined the duration of immunity generated by ZIKV infection. In this study, we rechallenged five rhesus macaques with ZIKV 22 to 28 months after a primary ZIKV infection. We show that primary ZIKV infection generates high titers of neutralizing antibodies that protect from detectable plasma viremia following rechallenge and persist for at least 22 to 28 months. While additional longitudinal studies are necessary with longer time frames, this study establishes a new experimentally defined minimal length of protective ZIKV immunity.IMPORTANCE ZIKV emerged as a vector-borne pathogen capable of causing illness in infected adults and congenital birth defects in infants born to mothers infected during pregnancy. Despite the decrease in ZIKV cases since the 2015-2016 epidemic, questions concerning the prevalence and longevity of protective immunity have left vulnerable communities fearful that they may become the center of next ZIKV outbreak. Although preexisting herd immunity in regions of past outbreaks may dampen the potential for future outbreaks to occur, we currently do not know the longevity of protective immunity to ZIKV after a person becomes infected. Here, we establish a new experimentally defined minimal length of protective ZIKV immunity. We show that five rhesus macaques initially infected with ZIKV 22 to 28 months prior to rechallenge elicit a durable immune response that protected from detectable plasma viremia. This study establishes a new minimal length of protective immunity.

Variations in maternal adenylate cyclase genes are associated with congenital Zika syndrome in a cohort from Northeast, Brazil.

BACKGROUND: Vertical transmission of Zika virus (ZIKV) is associated with congenital malformations but the mechanism of pathogenesis remains unclear. Although host genetics appear to play a role, no genetic association study has yet been performed to evaluate this question. In order to investigate if maternal genetic variation is associated with Congenital Zika Syndrome (CZS), we conducted a case-control study in a cohort of Brazilian women infected with ZIKV during pregnancy. METHODS: A total of 100 women who reported symptoms of zika during pregnancy were enrolled and tested for ZIKV. Among 52 women positive for ZIKV infection, 28 were classified as cases and 24 as controls based on the presence or absence of CZS in their infants. Variations in the coding region of 205 candidate genes involved in cAMP signaling or immune response were assessed by high throughput sequencing and tested for association with development of CZS. RESULTS: From the 817 single nucleotide variations (SNVs) included in association analyses, 22 SNVs in 17 genes were associated with CZS under an additive model (alpha = 0.05). Variations c.319T>C (rs11676272) and c.1297G>A, located at ADCY3 and ADCY7 genes showed the most prominent effect. The association of ADCY3 and ADCY7 genes was confirmed using a Sequence Kernel Association Test to assess the joint effect of common and rare variations, and results were statistically significant after adjustment for multiple comparisons (P < 0.002). CONCLUSION: These results suggest that maternal ADCY genes contribute to ZIKV pathogenicity and influence the outcome of CZS, being promising candidates for further replication studies and functional analysis.

Análise da morbimortalidade perinatal na infecção congênita pelo vírus Zika / Analysis of perinatal morbidity and mortality in congenital Zika virus infection

A infecção materna pelo vírus Zika tende a causar mais efeitos prejudiciais ao feto e à criança do que à mãe, devido ao grande potencial de graves consequências para o feto, como abortos, perda fetal, baixo peso ao nascer e vários tipos de malformações congênitas. A epidemia de microcefalia instalada no Brasil em 2015 e 2016 motivou essa dissertação de mestrado cujo objetivo é estudar a frequência de ocorrência dos desfechos na prole resultante da infecção congênita pelo vírus Zika e correlacioná-los com o momento da infecção viral durante a gravidez. Este estudo teve como propósito contribuir não apenas com a ampliação de conhecimentos nessa área, ainda em investigação, mas também com subsídios para o sistema de saúde brasileiro atender a população acometida pela epidemia. O método utilizado foi descritivo, transversal, que partiu de estudo prospectivo de coorte da infecção pelo vírus Zika, já em andamento no Instituto Nacional de Saúde da Mulher e do Adolescente Fernandes Figueira / Fundação Oswaldo Cruz. Da prole das mães infectadas na gestação 66,3%(IC 95% 59,1-73,1) foi assintomática e 33,7% (IC 95% 26,9-40,9) apresentaram alterações no exame e/ou foram a óbito após o nascimento. Cerca de 22,5% (IC 95% 16,7-29,1) tiveram microcefalia/atrofia cerebral, restando 11,2% (IC 95% 7,0-16,6) que apresentaram manifestações menos agressivas da infecção, porém com características sugestivas do espectro da doença congênita pelo VZ. O total de microcefalia foi 18,7% (IC 95% 13,4-25,0), sendo 12.7% (IC 95% 8,4-18,4) severa. A proporção de casos de recém-nascidos pequenos para idade gestacional foi 21,9% (IC 95% 16,2-28,5), sendo que cerca da metade correspondeu a recém-nascidos abaixo do P3, 11,2% (IC 95% 7,0-16,6). O total de pré-termos foi 15,5% (IC 95% 10,6-21,5). Os 2 óbitos fetais e os 4 neomortos encontrados representam 1% (IC 95% 0,1-3,7) e 2%( IC 95% 0,5-5,3%), respectivamente. De maneira geral quanto mais precoce os sintomas na gestação maior o número de recém-nascidos com alterações sugestivas da infecção VZ. Dos recém-nascidos com manifestações da infecção congênita pelo VZ, a sintomatologia materna ocorreu em 20,8%, 6,5% e 2,7% respectivamente no 1º, 2º e 3º trimestres gestacionais. O estudo confirmou relações já apresentadas em outros trabalhos, de que quanto mais precoce a infecção na gestação, maior morbimortalidade dos acometidos. O destaque foi ter encontrado um maior percentual de nascidos pequenos para idade gestacional comparando com a população brasileira e com os demais estudos da população de recém-nascidos expostos ao VZ na gestação. O nascimento de pequenos para idade gestacional por uma restrição do crescimento durante o desenvolvimento intrauterino pode ser consequência desta infecção sobre o feto na gestação. Assim o encontro desse achado no exame de ultrassom fetal também pode servir como mais um recurso para diagnóstico precoce da infecção pelo VZ. As graves consequências a curto e longo prazo do nascer pequeno para a idade gestacional precisam ser consideradas como uma demanda resultante dessa epidemia para adequação do planejamento assistencial à saúde dessa população.

The maternal infection by Zika virus tends to cause more harmful effects to the fetus and the child than to the mother, due to the large potential for serious consequences for the fetus, such as miscarriages, fetal loss, premature birth, low birth weight and various types of congenital malformations. The epidemic of microcephaly installed in Brazil in 2015 and 2016 originated this master's thesis whose objective is to study the frequency of occurrence of the outcomes in the fetus resulting from the congenital infection by the Zika virus and to correlate them with the time point of the viral exposure during pregnancy. Therefore, this study aimed to contribute not only with the expansion of knowledge in this area, still little known, but also with subsidies for the Brazilian health care system to assist the population affected by the epidemic. The method used was a descriptive, cross-sectional study within in a prospective cohort study of Zika virus infection, already in progress at the Instituto Nacional de Saúde da Mulher, da Criança e do Adolescente Fernandes Figueira / Fundação Oswaldo Cruz. The majority of the offspring of the infected mothers in pregnancy were asymptomatic (66.3%, 95% CI 59.1-73.1) and 33.7% (95% CI, 26.9-40.9) presented alterations in the examination and / or died after birth. About 22.5% (95% CI, 16.7-29.1) had microcephaly / cerebral atrophy, remaining 11.2% (IC 95% 7.0-16.6), which presented less aggressive manifestations due to infection, but with characteristics suggestive of the spectrum of congenital disease by ZV. The total microcephaly was 18.7% (95% CI 13.4-25.0), 12.7% (CI 95% 8.4-18.4) classified as severe. The proportion of cases of newborns small for gestational age was 21.9% (95% CI 16.2-28.5), and around half of them were newborns below P3, 11.2% (CI 95% 7.0-16.6). The total of preterm births was 15.5% (95% CI 10.6-21.5). The 2 fetal deaths and the 4 newborns found represent 1% (95% CI 0.1-3.7) and 2% (95% CI 0.5-5.3%), respectively. In general, the earlier the symptoms in gestation, the greater the number of newborns with changes suggestive of ZV infection. Of the newborns with manifestations of congenital infection, maternal symptoms occurred in 20.8%, 6.5% and 2.7% respectively in the 1st, 2nd and 3rd gestational trimesters. The study confirmed the relationships already reported by other studies, that the earlier the infection in pregnancy, the greater the morbidity and mortality of those affected. The highlight was to have found a higher percentage of small births for gestational age than the other studies of the population of newborns exposed to ZV during pregnancy. The growth restriction during the intrauterine development may occur as a consequence of this infection on the fetus. Thus the finding of intrauterine growth restriction in fetal Ultrasound may also serve as another resource for the diagnosis of ZV infection during pregnancy. The serious short and long-term consequences of being born small for gestational age need to be considered in the adequacy of health care planning for this new population resulting from the epidemic of ZV.