Microcephaly in Colombia before the Zika outbreak: A systematic literature review

Fetal, neonatal, and infant outcomes associated with maternal Zika virus infection during pregnancy: A systematic review and meta-analysis

The occurrence of fetal and neonatal disorders in pregnant women with Zika virus infection in the literature is not consistent. This study aims to estimate the prevalence rate of these disorders in fetuses/neonates of pregnant women with confirmed or probable infection by Zika virus. A systematic review with meta-analysis was conducted in November 2020. Cohort studies that contained primary data on the prevalence of unfavorable outcomes in fetuses or neonates of women with confirmed or probable Zika virus infection during pregnancy were included. A total of 21 cohort studies were included, with a total of 35,568 pregnant women. The meta-analysis showed that central nervous system abnormalities had the highest prevalence ratio of 0.06 (95% CI 0.03-0.09). Intracranial calcifications had a prevalence ratio of 0.01 (95% CI 0.01-0.02), and ventriculomegaly 0.01 (95% CI 0.01-0.02). The prevalence ratio of microcephaly was 0.03 (95% CI 0.02-0.05), fetal loss (miscarriage and stillbirth) was 0.04 (95% CI 0.02-0.06), Small for Gestational Age was 0.04 (95% CI 0.00-0,09), Low Birth Weight was 0.05 (95% CI 0.03-0.08) and Prematurity was 0.07 (95% CI 0.04-0.10). The positivity in RT-PCR for ZIKV performed in neonates born to infected mothers during pregnancy was 0.25 (95% CI 0.06-0.44). We also performed the meta-analysis of meta-analysis for microcephaly with the prevalence ratios from other two previously systematic reviews: 0.03 (95% CI 0.00-0.25). Our results contribute to measuring the impact of Zika virus infection during pregnancy on children's health. The continuous knowledge of this magnitude is essential for the implementation development of health initiatives and programs, in addition to promoting disease prevention, especially in the development of a vaccine for Zika virus. PROSPERO protocol registration: http://www.crd.york.ac.uk/PROSPERO/display_record.php?ID=CRD42019125543.

Birth Defects and Long-Term Neurodevelopmental Abnormalities in Infants Born During the Zika Virus Epidemic in the Dominican Republic

Background:

When acquired during pregnancy, Zika virus (ZIKV) infection can cause substantial fetal morbidity, however, little is known about the long-term neurodevelopmental abnormalities of infants with congenital ZIKV exposure without microcephaly at birth.

Methods:

We conducted a cross sectional study to characterize infants born with microcephaly, and a retrospective cohort study of infants who appeared well at birth, but had possible congenital ZIKV exposure. We analyzed data from the Dominican Ministry of Health’s (MoH) National System of Epidemiological Surveillance. Neurodevelopmental abnormalities were assessed by pediatric neurologists over an 18-month period using Denver Developmental Screening Test II.

Results:

Of 800 known live births from 1,364 women with suspected or confirmed ZIKV infection during pregnancy, 87 (11%) infants had confirmed microcephaly. Mean head circumference (HC) at birth was 28.1 cm (SD ± 2.1 cm) and 41% had a HC on the zero percentile for gestational age. Of 42 infants with possible congenital ZIKV exposure followed longitudinally, 52% had neurodevelopmental abnormalities, including two cases of postnatal onset microcephaly, during follow-up. Most abnormalities resolved, though two infants (4%) had neurodevelopmental abnormalities that were likely associated with ZIKV infection and persisted through 15–18 months.

Conclusions:

In the DR epidemic, 11% of infants born to women reported to the MoH with suspected or confirmed ZIKV during pregnancy had microcephaly. Some 4% of ZKV-exposed infants developed postnatal neurocognitive abnormalities. Monitoring of the cohort through late childhood and adolescence is needed.

Measurement of Head Circumference: Implications for Microcephaly Surveillance in Zika-Affected Areas

Worldwide recognition of the Zika virus outbreak in the Americas was triggered by an unexplained increase in the frequency of microcephaly. While severe microcephaly is readily identifiable at birth, diagnosing less severe cases requires comparison of head circumference (HC) measurement to a growth chart. We examine measured values of HC and digit preference in those values, and, by extension, the prevalence of microcephaly at birth in two data sources: a research study in Honduras and routine surveillance data in Uruguay. The Zika in Pregnancy in Honduras study enrolled pregnant women prenatally and followed them until delivery. Head circumference was measured with insertion tapes (SECA 212), and instructions including consistent placement of the tape and a request to record HC to the millimeter were posted where newborns were examined. Three indicators of microcephaly were calculated: (1) HC more than 2 standard deviations (SD) below the mean, (2) HC more than 3 SD below the mean (referred to as “severe microcephaly”) and (3) HC less than the 3rd percentile for sex and gestational age, using the INTERGROWTH-21st growth standards. We compared these results from those from a previous analysis of surveillance HC data from the Uruguay Perinatal Information System (Sistema Informático Perinatal (SIP). Valid data on HC were available on 579 infants, 578 with gestational age data. Nine babies (1.56%, 95% CI 0.71–2.93) had HC < 2SD, including two (0.35%, 95% CI 0.04–1.24) with HC < 3SD, and 11 (1.9%, 95% CI, 0.79–3.02) were below the 3rd percentile. The distribution of HC showed strong digit preference: 72% of measures were to the whole centimeter (cm) and 19% to the half-cm. Training and use of insertion tapes had little effect on digit preference, nor were overall HC curves sufficient to detect an increase in microcephaly during the Zika epidemic in Honduras. When microcephaly prevalence needs to be carefully analyzed, such as during the Zika epidemic, researchers may need to interpret HC data with caution.

Dose-response relationship between intergenerational contact frequency and depressive symptoms amongst elderly Chinese parents: a cross-sectional study

Background

Given the high prevalence of depressive symptoms amongst the elderly Chinese population and the significance of intergenerational contact in this demographic group, the purpose of this study was to examine the association and dose–response relationship between the frequency of intergenerational contact and depressive symptoms.

Methods

Data were obtained from the third wave of the China Health and Retirement Longitudinal Study. A total of 5791 participants at age 60 or older were included in this study. Depressive symptoms were defined by the 10-item version of the Centre for Epidemiologic Studies Depression Scale. Intergenerational contact included in-person meeting and remote connecting, and they were analysed separately. Intergenerational contact frequency was classified into ten categories and then treated as a continuous variable for analysis. We performed univariate and multivariate logistic regressions to identify risk covariables. Restrictive cubic spline analysis was used to examine the dose–response relationship between intergenerational contact frequency and the outcome of depressive symptoms.

Results

Both the frequency of meeting and the frequency of connecting with children were independently associated with depressive symptoms in the elderly, and the odds ratios for depressive symptoms increased with decreasing frequencies (P < 0.01). There was a negative dose–response relationship between intergenerational contact frequency and depressive symptoms. The odds of depressive symptoms steadily decreased with increasing frequency of meeting with their children. Following an initial increase, the odds rapidly decreased as the frequency of connecting with children increased with an inflection point at once a monthly. Both associations were nonlinear (P < 0.001).

Conclusions

Our findings revealed a negative dose–response relationship between intergenerational contact frequency and depressive symptoms in the elderly Chinese population. Thus, future health interventions should consider cultural norms in shaping the mental well-being of Chinese elderly persons.

Zika and women's sexual and reproductive health: Critical first steps to understand the role of gender in the Colombian epidemic

Objectives

To describe the mechanisms of implementation of Zika virus diagnosis, prevention, and management guidelines in Colombia, and to characterize their influence on efforts to defend sexual and reproductive rights.

Methods

A qualitative study performed between February and April 2018 in three municipalities in Colombia. We conducted 30 semistructured interviews and five focus groups with key informants who played a role during the epidemic. These included decision‐makers, program coordinators, healthcare providers, pregnant women diagnosed with Zika virus, and members of affected communities.

Results

We identified barriers to and facilitators for the implementation of the national Zika virus response plan. Barriers included a lack of coordination between vector control efforts and in the realms of sexual and reproductive rights. Facilitators included healthcare providers’ response to the epidemic, the development of technical skills, and the establishment of coordination and referral networks across different institutions.

Conclusion

A multidimensional approach that considers healthcare services, gender issues, and the environment is crucial. We highlight the epidemic's effects on women's sexual and reproductive rights, mainly related to inequalities in sexual and reproductive health such as the increased risk of sexually transmitted infections experienced by the poorest and most vulnerable women.

The Zika virus epidemic has different effects on women's and men's reproductive health. This calls for a multidimensional approach to the epidemic.

Measurement error, microcephaly prevalence and implications for Zika: an analysis of Uruguay perinatal data

BACKGROUND AND OBJECTIVE

The Zika virus outbreak has drawn attention to microcephaly, whose definition is based on head circumference measuring below a percentile or number of SDs below the mean. The objective of this analysis was to assess how differences in measurement precision might affect prevalence and trends of microcephaly.

METHODS

Data from all births in Uruguay during 2010-2015 were obtained from the Perinatal Information System. The prevalence of births with microcephaly was calculated based on head circumference measurement at birth applying the INTERGROWTH-21^st standards for sex and gestational age, and compared by method of ascertaining gestational age.

RESULTS

Rounding and digit preference was observed: 74% of head circumference measurements were reported as a whole centimetre value. The prevalence of births varied substantially by the criterion used to define microcephaly (<3 SD, <2 SD, <3rd percentile for gestational age) and could be halved or doubled based on adding or subtracting a half-centimetre from all reported head circumference measurements. If 4 days were added to gestational age calculations, rather than using completed gestational weeks (without days) for gestational age reporting, the prevalence was 1.7-2 times higher.

DISCUSSION

Rounding in measurement of head circumference and reporting preferences of gestational age may have contributed to a lower prevalence of microcephaly than expected in this population. Differences in head circumference measurement protocols and gestational age dating have the potential to affect the prevalence of babies reported with microcephaly, and this limitation should be acknowledged when interpreting head circumference data collected for surveillance.