Zika virus infection in pregnancy and infant growth, body composition in the first three months of life: a cohort study

Feeding practices and weight status of children with congenital Zika syndrome: A longitudinal study in Brazil

OBJECTIVE

The objective of this study was to describe feeding practices and weight status in a cohort of children with congenital Zika syndrome (CZS) in northeastern Brazil.

METHODS

This longitudinal study of children with CZS (N = 156) included data collection on child feeding practices and weight status at five timepoints between 2018 and 2022. The average age of the children was 32.1 months at enrollment and 76.6 months at the fifth assessment. Multilevel models, with repeated observations nested within children, were used to estimate time-related differences in each outcome.

RESULTS

Use of enteral feeding, such as gastrostomy, increased from 19.2% to 33.3% over 4 years (p < .001). Among children who did not exclusively use an enteral feeding method, the percentage experiencing at least one dysphagia-associated behavior, such as coughing or gagging, increased from 73.9% to 85.3% (p = .030) while consuming liquids and from 36.2% to 73.5% (p = .001) while consuming solids. Based on weight-for-age z-scores, the percentage of children who were moderately or severely underweight increased from 42.5% to 46.1% over the 4 years but was not statistically significant. Children exclusively using an enteral feeding method had significantly decreased odds of being underweight at assessments 3, 4, and 5.

CONCLUSIONS

These data highlight the ongoing and increasing challenges of feeding young children with CZS. Our findings elucidate the physiological reasons children with CZS may be underweight and point to intervention targets, such as enteral feeding, to improve their feeding practices.

Feeding characteristics and growth among children with prenatal exposure to Zika virus with and without microcephaly in the microcephaly epidemic research group pediatric cohort

OBJECTIVE

To describe the feeding characteristics and growth of children with prenatal exposure to Zika virus (ZIKV) from birth to 48 months.

DESIGN

Using data from the prospective Microcephaly Epidemic Research Group Pediatric Cohort (MERG-PC), children without microcephaly born to mothers with evidence of ZIKV infection during pregnancy (ZIKV-exposed children without microcephaly) and children with Zika-related microcephaly were compared using repeated cross-sectional analyses within the following age strata: birth; 1 to 12; 13 to 24; 25 to 36; and 37 to 48 months. The groups were compared in relation to prematurity, birth weight, breastfeeding, alternative feeding routes, dysphagia and anthropometric profiles based on the World Health Organization Anthro z-scores (weight-length/height, weight-age, length/height-age and BMI-age).

RESULTS

The first assessment included 248 children, 77 (31.05%) with microcephaly and 171 (68.95%) without microcephaly. The final assessment was performed on 86 children. Prematurity was 2.35 times higher and low birth weight was 3.49 times higher in children with microcephaly. The frequency of breastfeeding was high (> 80%) in both groups. On discharge from the maternity hospital, the frequency of children requiring alternative feeding route in both groups was less than 5%. After 12 months of age, children with microcephaly required alternative feeding route more often than children without microcephaly. In children with microcephaly, the z-score of all growth indicators was lower than in children without microcephaly.

CONCLUSIONS

Children with Zika-related microcephaly were more frequently premature and low birth weight and remained with nutritional parameters, i.e., weight-for-age, weight-for-length/height and length/height-for-age below those of the children without microcephaly.

Zika virus infection leads to hormone deficiencies of the hypothalamic-pituitary-gonadal axis and diminished fertility in mice

IMPORTANCE

Zika virus (ZIKV) infection in pregnant women during the third trimester can cause neurodevelopmental delays and cryptorchidism in children without microcephaly. However, the consequences of congenital ZIKV infection on fertility in these children remain unclear. Here, using an immunocompetent mouse model, we reveal that congenital ZIKV infection can cause hormonal disorders of the hypothalamic-pituitary-gonadal axis, leading to reduced fertility and decreased sexual preference. Our study has for the first time linked the hypothalamus to the reproductive system and social behaviors after ZIKV infection. Although the extent to which these observations in mice translate to humans remains unclear, these findings did suggest that the reproductive health and hormone levels of ZIKV-exposed children should receive more attention to improve their living quality.

Infection, nutritional status, and body composition: Associations at birth and 6 months postnatally in Soweto, South Africa

INTRODUCTION

The impact of infection on infant nutritional status, body size, and growth is well documented. However, research into the impact of infection on infant body composition is limited. Greater understanding is, therefore, needed on the effects of infection in early life.

METHODS

Associations between a composite morbidity index consisting of the sum of the cumulative tallies for a range of symptoms representing infection and morbidity in the infants and nutritional status (height-for-age (HAZ), and weight-for-height (WHZ)), and body composition (fat-free mass (FFM), fat mass (FM), fat-free mass index (FFMI), and fat mass index (FMI)) at 6 months of age were investigated using hierarchical regression analysis.

RESULTS

The sample comprised data between birth and 6 months postnatally, of 156 infants who were a priori born healthy in Soweto, South Africa. Morbidity, over the cumulative period of birth to 6 months, was associated with lower FMI (β = -1.77) and lower FM (β = -0.61), and conversely with higher FFM (β = 0.94), in infants at 6 months. No associations were found between the morbidity index and FFMI, HAZ, and WHZ. Increased birthweight was associated with a higher FFM (β = 0.66), HAZ (β = 1.14), and WHZ (β = 0.87). Finally, safely managed sanitation facilities, representative of reduced environmental exposure to fecal-oral transmission pathways were associated with a higher HAZ (β = 1.21).

DISCUSSION

Reduction in FMI and FM and exposure to inflammatory cytokines associated with mounting an immune response could alter phenotypic trajectories during to this period of plasticity. From a public health perspective, these results imply that it is important to intensify efforts to prevent infection in infants in the first 6 months postnatally, and that these efforts should concentrate on access to safely managed sanitation facilities.

Congenital Zika Syndrome and Disabilities of Feeding and Breastfeeding in Early Childhood: A Systematic Review

Background: The Zika virus outbreak has affected pregnant women and their infants. Affected infants develop microcephaly and other congenital malformations referred to as congenital Zika syndrome. The neurological manifestations of congenital Zika syndrome may result in some feeding disorders, including dysphagia, swallowing dysfunction and choking while feeding. The aim of this study was to assess the prevalence of feeding and breastfeeding difficulties in children with congenital Zika syndrome and to estimate the risk of developing feeding disabilities. Methods: We searched PubMed, Google Scholar and Scopus for studies published from 2017 to 2021. From the total of 360 papers, reviews, systematic reviews, meta-analyses and publications in languages other than English were excluded. Therefore, the final sample of our study consisted of 11 articles about the feeding/breastfeeding difficulties of infants and children with congenital Zika syndrome. Results: Infants and children with congenital Zika syndrome were likely to suffer from feeding difficulties at various levels, including breastfeeding. Dysphagia problems ranged from 17.9% to 70%, and nutritional and non-nutritive suckling of infants was also affected. Conclusions: In addition to continuing to investigate the neurodevelopment of affected children, future research should also focus on the severity of factors influencing the degree of dysphagia, as well as the impact of breastfeeding on the child’s overall development.

Effect of neurodevelopmental treatment in children with congenital Zika syndrome: A pilot study

AIM

To evaluate the effects of neurodevelopmental treatment (NDT) in children with congenital Zika syndrome (CZS).

METHODS

This prospective, interventional cohort study involved children with CZS undergoing follow-up at a specialist centre in northeastern Brazil. The duration of the proposed NDT protocol was 1 year, with 45-min sessions delivered one to five times weekly. Motor function, weight, height, head circumference and the incidence of comorbidities were evaluated in children before protocol initiation and then at 3, 6 and 12 months of treatment.

RESULTS

Thirty children were evaluated (age mean 30.1 ± 3 months). Motor function improved from baseline to 6 months (P = 0.001). No difference in weight and head circumference z-score (P = 0.51 and P = 0.29, respectively), but an increase in height z-score (P < 0.001) was observed over the evaluation period. There was a reduction in the incidence of upper respiratory tract infections, pneumonia and urinary tract infections over the follow-up period.

CONCLUSIONS

NDT proved to be a viable treatment approach that can improve motor function and reduce the incidence of comorbidities in children with CZS, while having no harmful effects on their growth.

Characteristics of children of the Microcephaly Epidemic Research Group Pediatric Cohort who developed postnatal microcephaly

The number of studies published on postnatal microcephaly in children with Congenital Zika Syndrome is small, clinical presentations vary and aspects of the evolution of these children remain unclarified. The present case series examined clinical characteristics and assessed the growth velocity of the head circumference, weight and height Z-scores in 23 children who developed postnatal microcephaly during follow-up in the Microcephaly Epidemic Research Group Pediatric Cohort. To estimate the change in the head circumference, weight and height Z-scores over time and compare the mean difference between sexes, we used multilevel mixed-effects linear regressions with child-specific random effects. Among these children, 60.9% (n = 14/23) presented with craniofacial disproportion, 60.9% (n = 14/23) with strabismus, 47.8% (n = 11/23) with early onset seizures, 47.8% (n = 11/23) with dysphagia and 43.5% (n = 10/23) with arthrogryposis. Of the 82.7% (n = 19/23) children who underwent neuroimaging, 78.9% (n = 15/19) presented with alterations in the central nervous system. Monthly growth velocity, expressed in Z-scores, of the head circumference was − 0.098 (95% CI % − 0.117 to − 0.080), of weight was: − 0.010 (95%-CI − 0.033 to 0.014) and of height was: − 0.023 (95%-CI − 0.046 to 0.0001). Postnatal microcephaly occurred mainly in children who had already presented with signs of severe brain damage at birth; there was variability in weight and height development, with no set pattern.

Pregnancy outcomes after SARS-CoV-2 infection by trimester: A large, population-based cohort study

Objectives

Data regarding women infected with SARS-CoV-2 during early trimesters are scarce. We aimed to assess preterm birth (PTB) and small-for-gestational-age (SGA) rates in a large and unselected cohort by trimester at infection and overall.

Design

A retrospective cohort study including all women with a positive SARS-CoV-2 RT-PCR test during a non-ectopic singleton pregnancy between February 21^st 2020 and July 2^nd 2021 (N = 2753). Each infected woman was matched to a non-infected pregnant woman by age, last menstruation date, sector, and socioeconomic status.

Methods

Logistic regression was conducted to assess the risks of PTB and SGA including an interaction between group and trimester of infection. Multivariable models included underlying diseases, previous abortions and null parity. Subgroup analyses were conducted on symptomatic infected women and matched non-infected women.

Results

A total of 2753 /2789 (98.7%) eligible women that were infected during pregnancy could be matched, among them, 17.4% and 48.4% were infected during the first and third trimesters, respectively. While first and second trimester infections were not associated with PTB (p>0.8), third trimester infections and in particular after 34 weeks of gestation had a greater risk of PTB with adjusted ORs of 2.76 (95% CI 1.63–4.67) and 7.10 (95% CI 2.44–20.61), respectively. PTB risk was further heightened in symptomatic third trimester infections (OR = 4.28, 95% CI 1.94–9.25). SGA risk was comparable between study groups across all trimesters of infection. Pregnancy loss incidence was similar in both groups (adjusted OR = 1.16; 95% CI 0.90–1.50).

Conclusion

SARS-CoV-2 infection was associated with increased risk of PTB only among women infected during late pregnancy, particularly among symptomatic women.

Placental Macrophage (Hofbauer Cell) Responses to Infection During Pregnancy: A Systematic Scoping Review

BACKGROUND

Congenital infection of the fetus via trans-placental passage of pathogens can result in severe morbidity and mortality. Even without transmission to the fetus, infection of the placenta itself is associated with pregnancy complications including pregnancy loss and preterm birth. Placental macrophages, also termed Hofbauer cells (HBCs), are fetal-origin macrophages residing in the placenta that are likely involved in responding to placental infection and protection of the developing fetus. As HBCs are the only immune cell present in the villous placenta, they represent one of the final opportunities for control of infection and prevention of passage to the developing fetus.

OBJECTIVE AND RATIONALE

The objective of this review was to provide a systematic overview of the literature regarding HBC responses during infection in pregnancy, including responses to viral, bacterial, and parasitic pathogens.

METHODS

PubMed and Scopus were searched on May 20th, 2021, with no limit on publication date, to identify all papers that have studied placental macrophages/Hofbauer cells in the context of infection. The following search strategy was utilized: (hofbauer* OR "hofbauer cells" OR "hofbauer cell" OR "placental macrophage" OR "placental macrophages") AND [infect* OR virus OR viral OR bacteri* OR parasite* OR pathogen* OR LPS OR "poly(i:c)" OR toxoplasm* OR microb* OR HIV)].

OUTCOMES

86 studies were identified for review. This included those that investigated HBCs in placentas from pregnancies complicated by maternal infection and in vitro studies investigating HBC responses to pathogens or Pathogen-Associated Molecular Patterns (PAMPs). HBCs can be infected by a variety of pathogens, and HBC hyperplasia was a common observation. HBCs respond to pathogen infection and PAMPs by altering their transcriptional, translational and secretion profiles. Co-culture investigations demonstrate that they can replicate and transmit pathogens to other cells. In other cases, they may eliminate the pathogen through a variety of mechanisms including phagocytosis, cytokine-mediated pathogen elimination, release of macrophage extracellular traps and HBC-antibody-mediated neutralization. HBC responses differ across gestation and may be influenced by pre-existing immunity. Clinical information, including gestational age at infection, gestational age of the samples, mode of sample collection and pregnancy outcome were missing for the majority of studies.

The legacy of ZikaPLAN: a transnational research consortium addressing Zika

Global health research partnerships with institutions from high-income countries and low- and middle-income countries are one of the European Commission's flagship programmes. Here, we report on the ZikaPLAN research consortium funded by the European Commission with the primary goal of addressing the urgent knowledge gaps related to the Zika epidemic and the secondary goal of building up research capacity and establishing a Latin American-European research network for emerging vector-borne diseases. Five years of collaborative research effort have led to a better understanding of the full clinical spectrum of congenital Zika syndrome in children and the neurological complications of Zika virus infections in adults and helped explore the origins and trajectory of Zika virus transmission. Individual-level data from ZikaPLAN`s cohort studies were shared for joint analyses as part of the Zika Brazilian Cohorts Consortium, the European Commission-funded Zika Cohorts Vertical Transmission Study Group, and the World Health Organization-led Zika Virus Individual Participant Data Consortium. Furthermore, the legacy of ZikaPLAN includes new tools for birth defect surveillance and a Latin American birth defect surveillance network, an enhanced Guillain-Barre Syndrome research collaboration, a de-centralized evaluation platform for diagnostic assays, a global vector control hub, and the REDe network with freely available training resources to enhance global research capacity in vector-borne diseases.

Physical Growth and Neurodevelopment of a Cohort of Children after 3.5 Years of Follow-up from Mothers with Zika Infection during Pregnancy-Third Report of the ZIKERNCOL Study

INTRODUCTION

In utero Zika virus (ZIKV) exposure has been related to a group of congenital structural abnormalities called the congenital Zika syndrome, which also has been related to neurodevelopment alterations even in normocephalic children. Physical growth has been less explored, and delayed growth and malnutrition have been reported.

OBJECTIVE

The objective of this study is to describe the growth and neurodevelopment features of normocephalic infants born from a cohort of mothers with RT-PCR confirmed ZIKV during pregnancy in Risaralda, Colombia.

METHODS

We conducted a retrospective cohort, including normocephalic children born from mothers with RT-PCR confirmed ZIKV infection during pregnancy in Risaralda, Colombia. Physical growth was measured using WHO standards, and neurodevelopment was measured with the abbreviated neurodevelopment scale 2 validated for Colombia.

RESULTS

After verifying inclusion and exclusion criteria, 16 children were followed during a median time of 28 months (IQR 23-31 months); for a total of 116 visits, 87.5% (n = 14) of the patients developed a growth alteration. Five presented post-natal microcephaly, and among them, four presented malnutrition or low height. Six patients developed macrocephaly. Patients with a normal head circumference had normal neurodevelopment. Only one patient with microcephaly persisted with impairment of the neurodevelopment at the end of follow-up. All the patients with macrocephaly had normal neurodevelopment.

DISCUSSION

Our study suggests that growth could be altered in infants with in utero Zika exposure. We found a high proportion of patients with overgrowth and macrocephaly. Future studies should consider endocrine follow-up of children born with in utero Zika exposure to explore these findings' possible aetiologies.

CONCLUSION

We found a high proportion of growth alterations, particularly with overgrowth features and macrocephaly. Our study suggests that in addition to neurodevelopment impairment, growth could be altered in infants and children with in utero Zika exposure, even in those patients born without CZS.

Time to Evaluate the Clinical Repercussions of Zika Virus Vertical Transmission? A Systematic Review

Background: Vertical transmission of Zika Virus (ZIKV) can be associated with several clinical features in newborn infants. The goal of the present review was to analyze the current state of knowledge regarding clinical repercussions following perinatal exposure to ZIKV in children up to 3 years of age. Methods: A systematic review of published studies was carried out, without the restriction of language or date of publication, identified in the databases PubMed, Virtual Health Library (BVS), Scopus, and Web of Science and the catalog for CAPES theses and dissertations. According to the proposed flowchart, the bibliographic search resulted in 1,563 papers. Of these, according to the eligibility criteria, 70 were selected for systematic review; all were published between 2016 and 2021. Results: Regarding clinical findings, 19 papers evaluated clinical imaging alterations, 21 ophthalmic manifestations, and 39 evaluated the central nervous system; of these, 15 analyzed neuro-psychomotor development. The remainder evaluated audiological (n = 14), nutritional (n = 14), orthopedic (n = 7), cardiorespiratory (n = 5), genitourinary (n = 3) or endocrinological (n = 1) manifestations. Conclusion: It is critical for studies to continue monitoring children with antenatal ZIKV exposure as they grow, given the unknown long-term repercussions of ZIKV and the recognized postnatal complications of this infection during pregnancy. Broader descriptions of observed clinical findings are also important in order to characterize the entire spectrum of disease in children. Systematic Review Registration: PROSPERO REGISTER: CRD42020205947.

Examining the Association of Socioeconomic Position with Microcephaly and Delayed Childhood Neurodevelopment among Children with Prenatal Zika Virus Exposure

Increased rates of Zika virus have been identified in economically deprived areas in Brazil at the population level; yet, the implications of the interaction between socioeconomic position and prenatal Zika virus exposure on adverse neurodevelopmental outcomes remains insufficiently evaluated at the individual level. Using data collected between September 2015 and September 2019 from 163 children with qRT-PCR and/or IgM-confirmed prenatal exposure to Zika virus participating in a prospective cohort study in Rio de Janeiro, Brazil (NCT03255369), this study evaluated the relationships of socioeconomic indicators with microcephaly at birth and Bayley-III neurodevelopmental scores during the early life course. Adjusted logistic regression models indicated increased odds of microcephaly in children born to families with lower household income (OR, 95% CI: 3.85, 1.43 to 10.37) and higher household crowding (OR, 95% CI: 1.83, 1.16 to 2.91), while maternal secondary and higher education appeared to have a protective effect for microcephaly compared to primary education (OR, 95% CI: 0.33, 0.11 to 0.98 and 0.10, 0.03 to 0.36, respectively). Consistent with these findings, adjusted linear regression models indicated lower composite language (−10.78, 95% CI: −19.87 to −1.69), motor (−10.45, 95% CI: −19.22 to −1.69), and cognitive (−17.20, 95% CI: −26.13 to −8.28) scores in children whose families participated in the Bolsa Família social protection programme. As such, the results from this investigation further emphasise the detrimental effects of childhood disadvantage on human health and development by providing novel evidence on the link between individual level socioeconomic indicators and microcephaly and delayed early life neurodevelopment following prenatal Zika virus exposure.

Serum Proteomics Reveals Alterations in Protease Activity, Axon Guidance, and Visual Phototransduction Pathways in Infants With In Utero Exposure to Zika Virus Without Congenital Zika Syndrome

In 2015, ZIKV infection attracted international attention during an epidemic in the Americas, when neurological disorders were reported in infants who had their mothers exposed to ZIKV during pregnancy. World Health Organization (WHO) epidemiological data show that 5 to 15% of neonates exposed to ZIKV in the uterus have complications included in abnormalities related to Congenital Zika Syndrome (CZS). The risk of complications after birth is not well documented, however, clinical evidence shows that 6% of infants exposed to ZIKV during pregnancy have complications present at birth, and this rate rises to 14% when medical monitoring is performed in all exposed infants, regardless of birth condition. Thus, the evaluation and monitoring of all exposed infants are of foremost importance as the development of late complications has been increasingly supported by clinical evidence. The identification of changes in protein profile of infants exposed to ZIKV without CZS could provide valuable findings to better understand molecular changes in this cohort. Here, we use a shotgun-proteomics approach to investigate alterations in the serum of infants without CZS symptoms but exposed to intrauterine ZIKV (ZIKV) compared to unexposed controls (CTRL). A complex pattern of differentially expressed proteins was identified, highlighting the dysregulation of proteins involved in axon orientation, visual phototransduction, and global protease activity in children exposed to ZIKV without CZS. These data support the importance of monitoring children exposed to ZIKV during gestation and without early CZS symptoms. Our study is the first to assess molecular evidence of possible late disorders in children victims of the ZIKV outbreak in the Americas. We emphasize the importance of medical monitoring of symptomatic and asymptomatic children, as apparently unexplained late neurological and eye disorders may be due to intrauterine ZIKV exposure.

Feeding modifications and additional primary caregiver support for infants exposed to Zika virus or diagnosed with congenital Zika syndrome: a rapid review of the evidence

OBJECTIVE

Infants exposed to Zika virus (ZIKV) or diagnosed with congenital Zika syndrome (CZVS) may present dysphagia, regurgitation and other feeding difficulties. They may require special feeding practices to minimise the risk of mortality, morbidity and developmental problems. Improving knowledge, skills and behaviours of caregivers may preserve health, maximise development and promote quality of life among affected infants. We reviewed intervention studies of modified feeding practices and additional primary caregiver support to improve outcomes among infants 0 to 12 months of age exposed to ZIKV or diagnosed with CZVS.

METHODS

Rapid review and meta-analysis. We searched PubMed/MEDLINE and contacted experts. The search is current to 18 July 2020. We planned a meta-analysis using fixed-effect models; if unfeasible, we intended to summarise studies narratively. We planned to assess risk of bias of included studies and quality of evidence using Cochrane guidance.

RESULTS

We identified 42 records for title and abstract screening; 14 were eligible for full-text assessment. Among these, no intervention studies were found. Eight observational studies reported on the nutritional status, feeding practices and outcomes among infants affected by ZIKV or diagnosed with CZVS. They are presented and discussed to provide a basis for future research.

CONCLUSIONS

While no intervention studies were found, evidence from eight observational studies highlights the need for early nutrition interventions and caregiver support among infants affected by ZIKV or diagnosed with CZSV. More research is needed to assess whether modifications of feeding practices and provision of additional primary caregiver support will impact outcomes of interest.

Cross-sectional study of the anthropometric characteristics of children with congenital Zika syndrome up to 12 months of life

Background

Little is known about physical development of children with Congenital Zika Syndrome (CZS). This study aims to evaluate the anthropometric characteristics of children with CZS up to 12 months.

Methods

This is a cross-sectional study developed with 46 children with CZS living in Bahia. We used the Public Health Events Register, Live Births Information System and Childcare Records of Primary Health Care Services. Descriptive analysis was performed by distributing absolute and relative frequencies and median and interquartile range. The Weight/Age (W/A), Length/Age (L/A), Weight/Length (W/L) and Head Circumference/Age (HC/A) indexes were calculated for each month and expressed in z-score values, and the results were evaluated individually and by group average. Values between ≥ − 2 and ≤ 2 standard deviations were used as reference. T-Student and Spearman’s Correlation Tests were applied to verify the existence of any relationship between maternal and children’s variables with the anthropometric indexes weight/age and height/age at birth and at 3, 6 and 12 months of age.

Results

The studied children had high proportions of low birth weight (23.9%), dysphagia (56.8%) and seizures (53.5%). The mean z-score for the HC/A index at birth was − 3.20 and remained below − 3 z-scores throughout the assessed period. The analysis of the indices equivalent to every single child’s anthropometric measurement showed a deficit in 20.4% of the W/A, 39.1% of the L/A, 9.2% of the W/L and 85.7% of the HC/A measurements. Distribution of the mean values of these anthropometric indices revealed a risk of delayed stature growth (L/A < -1 z-score). There was a statistically significant association between L/A at 12 months and dysphagia (p = 0.0148) and a positive correlation between breastfeeding time and W/A. No statistically significant correlation was found between any other tested variables.

Conclusions

We observed a deficit in the HC/A index, which is a common feature in CZS, but also a high proportion of W/A and L/A deficit. The average group z-score highlighted the risk of delay in stature growth for age, which calls attention to the need for health interventions, as this condition exposes them to a higher risk of morbidity and mortality.

Zika virus seroprevalence in women who gave birth during Zika virus outbreak in Brazil - a prospective observational study

Background

The recent Zika virus (ZIKV) outbreak in Brazil started in August 2015 and ended in May 2017 without effective public health measures for its control have been taken. The immunological status of a community may not only predict future outbreaks as well to answer questions regarding ZIKV not known yet.

Objective

To verify the seroprevalence of ZIKV in a group of women who were pregnant during the Zika virus outbreak in Recife, three to nine months after the delivery, and to evaluate the neurodevelopment of their children.

Methods

A cross-sectional study enrolled participants of a cohort study held at Instituto de Medicina Integral Professor Fernando Figueira (IMIP) during the ZIKV outbreak in Recife. Mothers who gave birth between the last trimester of 2015 and the first semester of 2016, period of the peak of microcephaly outbreak in Recife, were invited. All participants had the serum tested by the anti-ZIKV IgG/IgM enzyme-liked immunosorbent assays, ELISA kit (Euroimmun, Lübeck, Germany). All children whose mothers presented positive serology for ZIKV performed the IgG/IgM ELISA test for ZIKV. These children were also evaluated by a neuropediatrician and the Denver II development screening test was applied.

Results

Among the 132 studied pregnant women who gave birth at the peak of ZIKV outbreak in Recife, all were ZIKV IgM negative and 81 (61,3%) had ZIKV IgG positive. Mothers ZIKV IgG positive had more fever and rash during the pregnancy as compared with mothers negative for ZIKV; respectively 27/81 (33,3%) vs 6/51 (11,7%), p = 0.005 and 22/81 (27,2%) vs 4 (7,8%), p = 0.016. Only one child had IgG positive serology for ZIKV. No children had neurodevelopment defect for the age group and the Denver II normal scores.

Conclusions

A high ZIKV IgG seroprevalence in pregnant women at the end of the ZIKV outbreak in Recife was found. This finding suggests that community protective immunity may have contributed to the end of ZIKV outbreak in Recife, Brazil.