T-Cell Immune Responses in Newborns and Long-Term Sequelae in Congenital Cytomegalovirus Infection (CYTRIC Study).

OBJECTIVE: To assess the role of T-lymphocyte immune responses in newborns with congenital cytomegalovirus (CMV) infection (cCMV) and their potential association with the development of long-term sequelae. STUDY DESIGN: A multicenter, prospective study from 2017 to 2022 was conducted across eight hospitals in Spain. Blood samples were collected within the first month of life from neonates diagnosed with cCMV. Intracellular cytokine staining was employed to evaluate the presence of CMV-specific interferon-gamma (IFN-γ)-producing CD8+ and CD4+ T lymphocytes (CMV-IFN-γ-CD8+ / CD4+) using flow cytometry. The development of sequelae, including hearing loss and neurologic impairment, was assessed during follow-up. RESULTS: In total, 64 newborns were included; 42 infants (65.6%) had symptomatic cCMV. The median age at last follow-up visit was 25.3 months (IQR 20.1-34.4). Eighteen infants had long-term sequelae (28.1%), predominantly hearing loss (20.3%) and neurologic disorders (15.6%). No relationship was observed between total count or percentage of CMV-specific IFN-γ-CD8+ or CD4+ lymphocytes and long-term sequelae. Multivariable analysis demonstrated an association between lower total lymphocyte count and long-term sequelae (aOR 0.549, 95% CI: 0.323-0.833), which requires further study. CONCLUSIONS: CMV-specific IFN-γ-CD4+ and CD8+ T-lymphocyte responses in neonates with cCMV were not predictive of long-term sequelae.

Renal Function Impairment in Children With Congenital Cytomegalovirus Infection: A Cross-sectional Study.

BACKGROUND: We aimed to determine the prevalence and severity of glomerular and tubular renal dysfunction by means of urinalysis in infants and toddlers with congenital cytomegalovirus infection (cCMV) and their association with cCMV disease, viruria and antiviral treatment. METHODS: This cross-sectional study was done using the Spanish Registry of Congenital Cytomegalovirus Infection. First-morning urine samples were collected from January 2016 to December 2018 from patients <5 years old enrolled in Spanish Registry of Congenital Cytomegalovirus Infection. Samples were excluded in case of fever or other signs or symptoms consistent with acute infection, bacteriuria or bacterial growth in urine culture. Urinary protein/creatinine and albumin/creatinine ratios, urinary beta-2-microglobulin levels, hematuria and CMV viruria were determined. A 0.4 cutoff in the urinary albumin/protein ratio was used to define tubular (<0.4) or glomerular (>0.4) proteinuria. Signs and symptoms of cCMV at birth, the use of antivirals and cCMV-associated sequelae at last available follow-up were obtained from Spanish Registry of Congenital Cytomegalovirus Infection. RESULTS: Seventy-seven patients (37 females, 48.1%; median [interquartile range] age: 14.0 [4.4-36.2] months) were included. Symptom-free elevated urinary protein/creatinine and albumin/creatinine ratios were observed in 37.5% and 41.9% of patients, respectively, with tubular proteinuria prevailing (88.3%) over glomerular proteinuria (11.6%). Proteinuria in the nephrotic range was not observed in any patients. In multivariate analysis, female gender was the only risk factor for tubular proteinuria (adjusted odds ratio = 3.339, 95% confidence interval: 1.086-10.268; P = 0.035). cCMV disease at birth, long-term sequelae, viruria or the use of antivirals were not associated with urinalysis findings. CONCLUSIONS: Mild nonsymptomatic tubular proteinuria affects approximately 40% of infants and toddlers with mostly symptomatic cCMV in the first 5 years of life.

Transmitted Drug Resistance and HIV Diversity Among Adolescents Newly Diagnosed With HIV in Spain.

BACKGROUND: Virologic characterization of newly HIV-diagnosed adolescents could help to improve their specific needs. The objective was to describe the transmitted drug resistance mutations (TDR) and its transmission by clusters in this population in Spain. METHODS: TDR to retrotranscriptase and protease inhibitors included in the WHO TDR list 2009 implemented in the Calibrated Population Resistance tool v8.0 (Stanford) were studied in HIV pol sequences from all HIV-diagnosed adolescents (12-19-year-old) enrolled during 2004-2019 period in the Spanish pediatric and adult (CoRISpe-CoRIS) cohorts. The found TDR were compared with the provided by the Stanford algorithm v9.0 2021. HIV-1 variants and transmission clusters were also studied. RESULTS: Among 410 HIV-1 adolescents diagnosed, 141 (34.4%) had available ART-naive sequences. They were mostly male (81.6%), Spanish (55.3%) and with behavioral risk (92.2%), mainly male-to-male sexual contact (63.1%). TDR prevalence was significantly higher by Stanford versus WHO list (18.4% vs. 7.1%; P = 0.004). The most prevalent TDR by the WHO list was K103N (3.6%) and by Stanford E138A (6.6%), both at retrotranscriptase. E138A, related to rilpivirine/etravirine resistance, was absent in the WHO list. One in 4 adolescents carried HIV-1 non-B variants. We described 5 transmission clusters, and 2 carried TDR mutations. CONCLUSIONS: Our data suggest a high TDR prevalence in adolescents with a new HIV diagnosis in Spain, similar to adults, 2 active TDR transmission clusters, and the need for the WHO TDR list update. These findings could have implications for the options of the recently available rilpivirine-related long-acting treatment and in first-line regimen election.

Universal screening programme for cytomegalovirus infection in the first trimester of pregnancy: study protocol for an observational multicentre study in the area of Barcelona (CITEMB study).

INTRODUCTION: Congenital cytomegalovirus (cCMV) is the leading cause of non-genetic sensorineural hearing loss and one of the main causes of neurological disability. Despite this, no universal screening programme for cCMV has been implemented in Spain. A recent study has shown that early treatment with valaciclovir, initiated in the first trimester and before the onset of signs in the fetus, reduces the risk of fetal infection. This finding favours the implementation of a universal screening programme for cCMV.The aim of this study is to evaluate the performance of a universal screening programme for cCMV during the first trimester of pregnancy in a primary care setting. METHODS AND ANALYSIS: This is an observational multicentre cohort study. The study will be conducted in four primary care settings from the Northern Metropolitan Barcelona area and three related hospitals and will last 3 years and will consist of a recruitment period of 18 months.In their first pregnancy visit, pregnant women will be offered to add a CMV serology test to the first trimester screening tests. Pregnant women with primary infection will be referred to the reference hospital, where they will continue treatment and follow-up according to the clinical protocol of the referral hospital, which includes treatment with valacyclovir. A CMV-PCR will be performed at birth on newborns of mothers with primary infection, and those who are infected will undergo neonatal follow-up for at least 12 months of life.For the analysis, the acceptance rate, the prevalence of primary CMV infections and the CMV seroprevalence in the first trimester of pregnancy will be studied. ETHICS AND DISSEMINATION: Ethical approval was obtained from the University Institute Foundation for Primary Health Care Research Jordi Gol i Gurina Ethics Committee 22/097-P dated 27 April 2022.

Neurological Short-Term Outcomes of a Cohort of Children Born to Zika Virus-Infected Mothers in Barcelona.

Zika virus (ZIKV) is a vector-borne flavivirus with a known teratogenic effect, yet the full spectrum has not been delineated. Studies on endemic areas tried to characterize the clinical outcomes of ZIKV intrauterine exposure. We aimed to describe early neurodevelopmental outcomes on prenatally ZIKV-exposed children in a non-endemic ZIKV area. This is a prospective observational cohort study conducted from May 2016 to December 2021 at Hospital Universitari Vall d'Hebron in Barcelona, Catalonia, Spain. We monitored for up to 24 months 152 children extracted from a pregnant women cohort with suspected ZIKV infection; eleven women (11/150; 7.3%) fulfilled the criteria for a confirmed ZIKV infection. Among the 152 children included, we describe two cases of congenital ZIKV syndrome (CZS) born from women with a confirmed ZIKV infection. Additionally, we describe five cases of other potentially ZIKV-related outcomes (OPZROs), all with normal birth cranial circumference and born to women with probable ZIKV infection. The low exposed prevalence of adverse outcomes in asymptomatic children at birth in a non-endemic area suggests that close follow-up should be addressed by primary care pediatricians instead of pediatric specialists. Further studies are needed to assess the effects of ZIKV intrauterine exposure beyond two years of life.

Factors associated with late presentation for HIV care in adolescents in Spain.

OBJECTIVE: Late presenters (LP) for HIV care are associated with higher morbidity and mortality rates. Our aim was to describe the characteristics associated with LP among adolescents in Spain. Identification of particular features may help in the design of strategies for improvement. METHODS: Late-presenting adolescents diagnosed at 12-19 years of age and enrolled in the Spanish paediatric and adult HIV/AIDS cohorts (CoRIS-CoRISpe) from 2004 to 2019 were selected. LP were defined as those presenting with CD4 count <350 cells/mm3 or an AIDS-defining event in the 6 months following HIV diagnosis. Confirmed low CD4 count in the next 3 months and before antiretroviral treatment initiation defined confirmed LP (cLP). RESULTS: Of 410 adolescents newly diagnosed with HIV, 303 (73.9%) had available data for assessing late presentation. Of these, 34.7% were LP and 23.7% were cLP. The median CD4 count for cLP was 235 cells/mm3 (interquartile range 122-285). In a multivariable analysis, adolescents at the highest risk of late presentation were early adolescents (age 12-14 years; odds ratio [OR] 6.50; 95% confidence interval [CI] 2.61-18.2), middle adolescents (age 15-17 years; OR 1.85; 95% CI 0.92-3.59), and adolescents born abroad (OR 1.71; 95% CI 0.97-3.00), particularly those of African origin (OR 3.08; 95% CI 1.38-6.79). CONCLUSIONS: One-quarter of adolescents presented late for HIV care in Spain. Early adolescents, middle adolescents, and those born abroad presented a sevenfold, twofold, and twofold higher risk of being cLP, respectively. Enhancing the awareness of HIV risk and the access to care, especially for younger and foreign adolescents, could help reduce late presentation and tackle the adolescent HIV epidemic.

Impact of the COVID-19 Pandemic on the Diagnosis of Congenital Cytomegalovirus Infection in Spain.

We conducted an observational study performed within the Spanish Registry of Children with congenital cytomegalovirus (cCMV) to evaluate the impact of the COVID-19 pandemic on the diagnosis of new cases of cCMV. Our study suggest a significant decrease in the monthly rate of new cCMV diagnoses during the COVID-19 pandemic.

Persistent dyselectrolytemia in a neonate induced by liposomal amphotericin B. A case report.

Background: Nephrotoxicity is the most frequent serious adverse effect associated with amphotericin B deoxycholate treatment, for this reason, in recent years it has been relegated from routine clinical practice and replaced by the new liposomal formulations that have less nephrotoxicity. Nevertheless, dyselectrolytemia are a frequent adverse effect of the use of liposomal amphotericin B that usually are resolved with the withdrawal of the drug. Case presentation: We present a preterm neonate of 25 weeks gestation, with preserved renal function and most electrolytes within normal limits for gestational age except for mild hyponatremia in the first month of life. Due to an infection of the central nervous system and growth of Candida albicans, he required treatment with endovenous liposomal amphotericin B as well as intrathecal amphotericin B deoxycholate showing severe hydroelectrolyte disturbances and clinical worsening compatible with possible tubulopathy showing hypokalemia and severe hyponatremia a few days after starting treatment that persisted over time even after withdrawal of both drugs. Subsequently to the main alterations described, hypomagnesemia, hypophosphatemia, glycosuria and tubular proteinuria were also observed. Calcium levels remained stable after amphotericin B administration and did not require supplementation. In preterm or low birth weight newborns who present unjustified, severe and difficult to correct hydroelectrolyte disturbances despite the usual treatment, a possible tubulopathy should be considered, whether hereditary, primary or secondary to toxins or drugs. What Is New and Conclusion: We present the first case reported in a neonate in whom dyselectrolithemia has been maintained over time after withdrawal of liposomal amphotericin B.

Congenital infection of SARS-CoV-2 in live-born neonates: a population-based descriptive study.

OBJECTIVE: To evaluate the evidence of mother-to-child transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). METHODS: This is a descriptive, multicentre, observational study in nine tertiary care hospitals throughout Spain. The study population was women with coronavirus disease 2019 during pregnancy. Mother-to-child transmission was defined as positive real-time RT-PCR of SARS-CoV-2 in amniotic fluid, cord blood, placenta or neonatal nasopharyngeal swabs taken immediately after birth. RESULTS: We included 43 women with singleton pregnancies and one with a twin pregnancy, as a result we obtained 45 samples of placenta, amniotic fluid and umbilical cord blood. The median gestational age at diagnosis was 34.7 weeks (range 14-41.3 weeks). The median interval between positive RT-PCR and delivery was 21.5 days (range 0-141 days). Fourteen women (31.8%, 95% CI 18.6%-47.6%) were positive at the time of delivery. There was one singleton pregnancy with SARS-CoV-2 RT-PCR positive in the placenta, amniotic fluid and umbilical cord blood (2.2%, 95% CI 0.1%-11.8%). Nasopharyngeal aspiration was performed on 38 neonates at birth, all of which were negative (0%, 95% CI 0%-9.3%). In 11 neonates the nasopharyngeal aspiration was repeated at 24-48 hours, and one returned positive (9.1%, 95% CI 0.2%-41.3%). CONCLUSIONS: The presence of SARS-CoV-2 in placenta, amniotic fluid and cord blood shows that mother-to-child transmission is possible but uncommon.

Safety of tocilizumab in COVID-19 pregnant women and their newborn: A retrospective study.

WHAT IS KNOWN AND OBJECTIVE: Tocilizumab is an IL-6 receptor inhibitor agent which has been proposed as a candidate to stop the inflammatory phase of infection by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). However, safety data of tocilizumab in pregnant women and their newborn are scarce. We aimed to describe maternal and neonatal safety outcomes associated with tocilizumab treatment in pregnant women with severe COVID-19. METHODS: This is a retrospective study of severe COVID-19 pregnant women, treated with tocilizumab in two Spanish hospitals between 1 March and 31 April 2020. Demographics, medical history, clinical and radiologic findings, treatment information and laboratory data of mothers and their newborns were collected from electronic medical records. RESULTS AND DISCUSSION: A total of 12 pregnant women were identified to have received tocilizumab during pregnancy in the two hospitals. Median gestational age at admission was 27.7 weeks (interquartile range, 18.0-36.4). Most of them received lopinavir/ritonavir, azithromycin and hydroxychloroquine, two patients received corticosteroids and one received interferon beta 1B. All 12 pregnancies resulted in live births. Somatometric values were normal for all newborns, and evolution at 14 and 28 days was favourable for all of them. Hepatotoxicity was observed in 2 patients, which improved or resolved at discharge. Cytomegalovirus reactivation was detected in another patient who had also received corticosteroids for 15 days, causing a congenital infection in her newborn. Both hepatotoxicity and viral reactivation adverse events were classified as possibly related to tocilizumab administration according to Naranjo's causality algorithm. WHAT IS NEW AND CONCLUSIONS: It does not appear that tocilizumab has detrimental effects for the mother and newborn. Close monitoring of infections should be considered, especially if other immunosuppressive agents are used.

Gestation and COVID-19: clinical and microbiological observational study (Gesta-COVID19).

BACKGROUND: The Coronavirus Disease 2019 (COVID-19) is a novel disease which has been having a worldwide affect since December 2019. Evidence regarding the effects of SARS-CoV-2 during pregnancy is conflicting. The presence of SARS-CoV-2 has been demonstrated in biological samples during pregnancy (placenta, umbilical cord or amniotic fluid); however, maternal and fetal effects of the virus are not well known. METHODS: Descriptive, multicentre, longitudinal, observational study in eight tertiary care hospitals throughout Spain, that are referral centres for pregnant women with COVID-19. All pregnant women with positive SARS-CoV-2 real-time reverse transcriptase polymerase chain reaction during their pregnancy or 14 days preconception and newborns born to mothers infected with SARS-CoV-2 will be included. They will continue to be followed up until 4 weeks after delivery. The aim of the study is to investigate both the effect of COVID-19 on the pregnancy, and the effect of the pregnancy status with the evolution of the SARS-CoV-2 disease. Other samples (faeces, urine, serum, amniotic fluid, cord and peripheral blood, placenta and breastmilk) will be collected in order to analyse whether or not there is a risk of vertical transmission and to describe the behaviour of the virus in other fluids. Neonates will be followed until 6 months after delivery to establish the rate of neonatal transmission. We aim to include 150 pregnant women and their babies. Ethics approval will be obtained from all the participating centres. DISCUSSION: There is little information known about COVID-19 and its unknown effects on pregnancy. This study will collect a large number of samples in pregnant women which will allow us to demonstrate the behaviour of the virus in pregnancy and postpartum in a representative cohort of the Spanish population.

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.

Clinical Outcomes of a Zika Virus Mother-Child Pair Cohort in Spain.

BACKGROUND: Zika virus (ZIKV) infection has been associated with congenital microcephaly and other neurodevelopmental abnormalities. There is little published research on the effect of maternal ZIKV infection in a non-endemic European region. We aimed to describe the outcomes of pregnant travelers diagnosed as ZIKV-infected in Spain, and their exposed children. METHODS: This prospective observational cohort study of nine referral hospitals enrolled pregnant women (PW) who travelled to endemic areas during their pregnancy or the two previous months, or those whose sexual partners visited endemic areas in the previous 6 months. Infants of ZIKV-infected mothers were followed for about two years. RESULTS: ZIKV infection was diagnosed in 163 PW; 112 (70%) were asymptomatic and 24 (14.7%) were confirmed cases. Among 143 infants, 14 (9.8%) had adverse outcomes during follow-up; three had a congenital Zika syndrome (CZS), and 11 other potential Zika-related outcomes. The overall incidence of CZS was 2.1% (95%CI: 0.4-6.0%), but among infants born to ZIKV-confirmed mothers, this increased to 15.8% (95%CI: 3.4-39.6%). CONCLUSIONS: A nearly 10% overall risk of neurologic and hearing adverse outcomes was found in ZIKV-exposed children born to a ZIKV-infected traveler PW. Longer-term follow-up of these children is needed to assess whether there are any later-onset manifestations.

Response to direct-acting antivirals for hepatitis C treatment in vertically HIV/HCV co-infected patients.

Direct-acting antivirals (DAAs) for HCV treatment have improved tolerance and efficacy among adults, but experience in vertical transmission is scarce. In our vertically HIV/HCV co-infected youth cohort of 58 patients, DAA achieved excellent rates of cure among naïve and pretreated individuals. Treating vertically infected seems important as 29.6% displayed advanced fibrosis at treatment initiation.

Pneumocystis jirovecii pneumonia in children. A retrospective study in a single center over three decades.

INTRODUCTION: Pneumocystis jirovecii pneumonia (PJP) is a life-threatening condition in immunocompromised children. Our aim is to analyze the epidemiologic and clinical characteristics of PJP cases in our setting, describing the prognosis and related risk factors. METHODS: Retrospective study including all pediatric patients (≤18 years) with PJP admitted to our hospital (January 1989-December 2016). Case definition: patient with acute pneumonitis and P.jirovecii detection in bronchoalveolar lavage or tracheal aspirate using methenamine silver or direct antibody fluorescence staining, or Real-Time Polymerase Chain Reaction. RESULTS: Twenty-five cases (0.9 cases/year) were identified. Median age was 2.2 years (interquartile range: 0.5-12.3), 64% were male, and 12% were receiving appropriate antimicrobial prophylaxis. Cytomegalovirus coinfection was detected in 26% cases. The most common underlying diseases were primary immunodeficiencies (36%) and 16% were human immunodeficiency virus (HIV)-infected children. Eighteen were admitted to the pediatric intensive care unit (PICU) and overall 30-day mortality was 20% (31.25% in HIV non-infected vs 0% in HIV-infected patients; OR: 0.33, 95% CI: 0.02-7.24, p=0.55). Clinical outcome was worse in girls and those patients requiring adjuvant steroid therapy. HIV non-infected patients, higher initial LDH, younger age and shorter time elapsed between diagnosis of PJP and the underlying disease were identified as risk factors to be admitted to the PICU (p=0.05, p=0.026, p=0.04 and p=0.001 respectively). CONCLUSION: Accompanying the widespread use of combined antiretroviral therapy, PJP has been diagnosed almost exclusively in HIV non-infected children at our institution. Moreover, significant higher morbidity rates associated with PJP are seen in this group of patients.

1H-NMR Urinary Metabolic Profile, A Promising Tool for the Management of Infants with Human Cytomegalovirus-Infection.

Congenital human cytomegalovirus (HCMV) infection is the most common mother-to-child transmitted infection in the developed world. Certain aspects of its management remain a challenge. Urinary metabolic profiling is a promising tool for use in pediatric conditions. The aim of this study was to investigate the urinary metabolic profile in HCMV-infected infants and controls during acute care hospitalization. Urine samples were collected from 53 patients at five hospitals participating in the Spanish congenital HCMV registry. Thirty-one cases of HCMV infection and 22 uninfected controls were included. Proton nuclear magnetic resonance (1H-NMR) spectra were obtained using NOESYPR1D pulse sequence. The dataset underwent orthogonal projection on latent structures discriminant analysis to identify candidate variables affecting the urinary metabolome: HCMV infection, type of infection, sex, chronological age, gestational age, type of delivery, twins, and diet. Statistically significant discriminative models were obtained only for HCMV infection (p = 0.03) and chronological age (p < 0.01). No significant differences in the metabolomic profile were found between congenital and postnatal HCMV infection. When the HCMV-infected group was analyzed according to chronological age, a statistically significant model was obtained only in the neonatal group (p = 0.01), with the differentiating metabolites being betaine, glycine, alanine, and dimethylamine. Despite the considerable variation in urinary metabolic profiles in a real-life setting, clinical application of metabolomics to the study of HCMV infection seems feasible.

The challenge of the laboratory diagnosis in a confirmed congenital Zika virus syndrome in utero: A case report.

INTRODUCTION: Zika virus (ZIKV) has caused one of the most challenging global infectious epidemics in recent years because of its causal association with severe microcephaly and other congenital malformations. The diagnosis of viral infections usually relies on the detection of virus proteins or genetic material in clinical samples as well as on the infected host immune responses. Serial serologic testing is required for the diagnosis of congenital infection when diagnostic molecular biology is not possible. PATIENT CONCERNS: A 2-year-old girl, born to a mother with confirmed ZIKV infection during pregnancy, with a confirmed ZIKV infection in utero, showed at birth a severe microcephaly and clinical characteristics of fetal brain disruption sequence compatible with a congenital ZIKV syndrome (CZS). DIAGNOSIS: ZIKV-RNA and ZIKV-IgM serological response performed at birth and during the follow-up time tested always negative. Serial serologic ZIKV-IgG tests were performed to assess the laboratory ZIKV diagnosis, ZIKV-IgG seroreversion was observed at 21 months of age. ZIKV diagnosis of this baby had to be relied on her clinical and radiological characteristics that were compatible with a CZS. INTERVENTIONS: The patient was followed-up as per protocol at approximately 1, 4, 9, 12, 18-21, and 24 months of age. Neurological, radiological, audiological, and ophthalmological assessment were performed during this period of time. Prompt rehabilitation was initiated to prevent potential adverse long-term neurological outcomes. OUTCOMES: The growth of this girl showed a great restriction at 24 months of age with a weight of 8.5 kg (-2.5 z-score) and a head circumference of 40.5 cm (-4.8 z-score). She also had a great neurodevelopmental delay at the time of this report. CONCLUSION: We presume that as a consequence of prenatal ZIKV infection, the fetal brain and other organs are damaged before birth through direct injury. Following this, active infection ends during intrauterine life, and as a consequence the immune system of the infant is unable to build up a consistent immune response thereafter. Further understanding of the mechanisms taking part in the pathogenesis of ZIKV congenital infection is needed. This finding might change our paradigm regarding serological response in the ZIKV congenital infection.