Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Jun 29;22(1):530.
doi: 10.1186/s12884-022-04860-3.

Population-based surveillance for congenital zika virus syndrome: a latent class analysis of recorded cases from 2015-2018

Enny S Paixao  1   2 , Laura C Rodrigues  3   4 , Maria da Conceição N Costa  4   5 , Rita de Cassia Oliveira de Carvalho-Sauer  6 , Wanderson K Oliveira  7 , Luciana L Cardim  4 , Lavinia Schuler-Faccini  8   9 , Roberto F S Andrade  4 , Moreno S Rodrigues  4 , Elizabeth B Brickley  3 , Rafael V Veiga  4 , Larissa C Costa  4 , Eduardo H Carmo  4 , Liam Smeeth  3 , Mauricio L Barreto  4   5 , Maria Gloria Teixeira  4   5
Affiliations

Population-based surveillance for congenital zika virus syndrome: a latent class analysis of recorded cases from 2015-2018

Enny S Paixao et al. BMC Pregnancy Childbirth. .

Abstract

Objective: This study aims to describe clinical findings and determine the medium-term survival of congenital zika syndrome (CZS) suspected cases.

Methods: A retrospective cohort study using routine register-based linked data. It included all suspected cases of CZS born in Brazil from January 1, 2015, to December 31, 2018, and followed up from birth until death, 36 months, or December 31, 2018, whichever came first. Latent class analysis was used to cluster unconfirmed cases into classes with similar combinations of anthropometry at birth, imaging findings, maternally reported rash, region, and year of birth. Kaplan-Meier curves were plotted, and Cox proportional hazards models were fitted to determine mortality up to 36 months.

Results: We followed 11,850 suspected cases of CZS, of which 28.3% were confirmed, 9.3% inconclusive and 62.4% unconfirmed. Confirmed cases had almost two times higher mortality when compared with unconfirmed cases. Among unconfirmed cases, we identified three distinct clusters with different mortality trajectories. The highest mortality risk was observed in those with abnormal imaging findings compatible with congenital infections (HR = 12.6; IC95%8.8-18.0) and other abnormalities (HR = 11.6; IC95%8.6-15.6) compared with those with normal imaging findings. The risk was high in those with severe microcephaly (HR = 8.2; IC95%6.4-10.6) and macrocephaly (HR = 6.6; IC95%4.5-9.7) compared with normal head size.

Conclusion: Abnormal imaging and head circumference appear to be the main drivers of the increased mortality among suspected cases of CZS. We suggest identifying children who are more likely to die and have a greater need to optimise interventions and resource allocation regardless of the final diagnoses.

Keywords: Congenital zika syndrome; Imaging findings; Microcephaly; Mortality.

PubMed Disclaimer

Conflict of interest statement

The authors declare that they have no competing interests.

Figures

Fig. 1
Fig. 1
Flowchart study population Brazil, 2015–2018
Fig. 2
Fig. 2
Number of suspected cases of CZS by month and region of birth comparing confirmed, probable, unconfirmed, and inconclusive cases Brazil, 2015–2018. *The Y axis differ because of the small number in some regions
Fig. 3
Fig. 3
Kaplan–Meier curves showing survival comparing confirmed/probable, Class 1, Class 2 and Class 3 of unconfirmed cases and live births born in the same period without a linked record of CZS (control group), Brazil, 2015–2018. Class 1 characterises the group with concomitant high proportion of microcephaly, SGA and abnormal imaging findings; Class 2 high proportion of normal head size and birth weight and the second highest proportion of abnormal findings in imaging tests; Class 3 high proportion of normal head size and birth weight and low proportion of cases with abnormal findings in imaging tests
See this image and copyright information in PMC

References

    1. Kleber de Oliveira W, et al. Increase in Reported Prevalence of Microcephaly in Infants Born to Women Living in Areas with Confirmed Zika Virus Transmission During the First Trimester of Pregnancy — Brazil, 2015. MMWR Morb Mortal Wkly Rep. 2016;65(9):242–7. doi: 10.15585/mmwr.mm6509e2. - DOI - PubMed
    1. Teixeira MG, Da Conceição N Costa M, De Oliveira WK, Nunes ML, Rodrigues LC. The epidemic of Zika virus-related microcephaly in Brazil: Detection, control, etiology, and future scenarios. Am J Public Health. 2016;106(4):601–5. doi: 10.2105/AJPH.2016.303113. - DOI - PMC - PubMed
    1. Rasmussen SA, Jamieson DJ, Honein MA, Petersen LR. Zika Virus and Birth Defects — Reviewing the Evidence for Causality. 2016. N Engl J Med. 10.1056/nejmsr1604338. - PubMed
    1. Ministério da Saúde do Brasil . RESP-Registro de Eventos Em Saúde Pública. 2017.
    1. Brasil F. Protocolo de Vigilância e resposta à ocorrência de Microcefalia e/ou Alteraçõe do sistema nervoso central central (SNC) - emergência de saúde pública de importância internacional - ESPII. 2nd ed. 2016. p. 55.