Microcephaly in north-east Brazil: a retrospective study on neonates born between 2012 and 2015

Abstract

ObjectiveTo assess the number of children born with microcephaly in the State of Paraíba, north-east Brazil.MethodsWe contacted 21 maternity centres belonging to a paediatric cardiology network, with access to information regarding more than 100 000 neonates born between 1 January 2012 and 31 December 2015. For 10% of these neonates, nurses were requested to retrieve head circumference measurements data from delivery-room books. We used three separate criteria to classify whether a neonate had microcephaly: (i) the Brazilian Ministry of Health proposed criterion: term neonates (gestational age ≥ 37 weeks) with a head circumference of less than 32 cm; (ii) Fenton curves: neonates with a head circumference of less than −3 standard deviation for age and gender; or (iii) the proportionality criterion: neonates with a head circumference of less than ((height/2))+10) ± 2.FindingsBetween 1 and 31 December 2015, nurses obtained data for 16 208 neonates. Depending on which criterion we used, the number of neonates with microcephaly varied from 678 to 1272 (4.2–8.2%). Two per cent (316) of the neonates fulfilled all three criteria. We observed temporal fluctuations of microcephaly prevalence from late 2012.ConclusionThe numbers of microcephaly reported here are much higher than the 6.4 per 10 000 live births reported by the Brazilian live birth information system. The results raise questions about the notification system, the appropriateness of the diagnostic criteria and future implications for the affected children and their families. More studies are needed to understand the epidemiology and the implications for the Brazilian health system.

Reproductive planning in times of Zika: getting pregnant or delaying plans? The opinion of the Brazilian Society of Assisted Reproduction Committee - a basis for a bioethical discussion

“…In the Paraíba study, the data from 16,208 children born in public hospitals between January 2012 and December 2015 revealed a prevalence of congenital microcephaly between 4% and 8%, depending on the criteria used. If these numbers were compared to the total number of live births in Paraíba in 2014 (n = 58,147), 4,652 cases of microcephaly would have occurred in the State according to the criteria adopted by the Brazilian Ministry of Health; Fenton growth charts would yield a total of 2,442 cases; 2,907 cases would have occurred according to proportionality criteria; or yet 1,105 cases would have been found if all diagnostic criteria were considered together (Soares de Araújo et al ., 2016). And if they were applied to the country as a whole, those percentages would yield an incidence of 1,900/100,000 live births per year.…”

Association between Zika virus and microcephaly in French Polynesia, 2013–15: a retrospective study

“…As of 19 February 2016, 28 countries of the region have reported cases 2 . Although ZIKV infection often leads to mild disease, the emergence of ZIKV in the Americas has coincided with a steep increase in Guillain-Barré syndrome, an autoimmune disease causing acute or subacute flaccid paralysis, and the birth of infants with neurological complications such as congenital microcephaly 3–5 .…”

Epidemiological and ecological determinants of Zika virus transmission in an urban setting

“…The rise in ZIKV incidence in FSA coincided temporally with an increase in cases of Guillain-Barré syndrome (GBS) and microcephaly (Faria et al, 2016a), with an unprecedented total of 21 confirmed cases of microcephaly in FSA between January 2015 and May 2017. There is wide statistical support for a causal link between ZIKV and severe manifestations such as microcephaly (Rubin et al, 2016; de Araújo et al, 2016; Soares de Araújo et al, 2016; Honein et al, 2017; Brasil et al, 2016; de Oliveira et al, 2017), and the proposed link in 2015 led to the declaration of the South American epidemic as an international public health emergency by the World Health Organization (WHO) in 2016; the response to which has been limited to vector control initiatives and advice to delay pregnancy in the affected countries (WHO, 2016b; WHO, 2016a). With few cohort studies published (Honein et al, 2017; Brasil et al, 2016) and the lack of an established experimental model for ZIKV infection (Aman and Kashanchi, 2016; Dowall et al, 2016), modelling efforts have taken a central role for advancing our understanding of the virus’s epidemiology (Chowell et al, 2016; Ferguson et al, 2016; Bogoch et al, 2016; Nishiura et al, 2016; Zhang et al, 2016; Perkins et al, 2016; Messina et al, 2016).…”