Context: COVID 19 vertical transmission is a great concern in different aspects of mother, child, healthcare staff and community safety and protection . There is lack of definitive evidence confirming or declining mother to child COVID 19 transmission . This article is an update on this challenging issue . Evidence Acquisition: This article is a comprehensive search in scientific major database from 1 January 2020 up to 25 April 2020 with the key words of “ COVID 19 ” and “ vertical transmission ” or “ neonatal ” . Two researchers reviewed all selected articles to extract data about neonatal COVID 19 and vertical transmission . Those reports that provided the results of PCR on fetus or neonate blood, amniotic fluid or pharyngeal secretion samples or elevated COVID 19 specific IgM were included . Those reports based on clinical COVID 19 characteristics or radiological findings were not included in data extraction . Thirty six articles have been reviewed and evidence supporting or against COVID 19 Vertical transmission have been extracted and discussed .
Results: Most previous studies on vertical COVID 19 transmission have been tested placenta, amniotic fluid, cord blood and newborn blood or pharyngeal swab sample using quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) that may show false negative results due to suboptimal sampling or inefficient viral load . Increased COVID 19 specific IgG/IgM antibodies have been reported in newborns from COVID 19 mothers; however, data is limited and longitudinal follow up is needed . Evidence supporting COVID 19 vertical transmission: Recent reports indicated that pharyngeal PCR test turned positive in first few hours of life in several neonates . Also increased level of COVID 19 specific IgM and IgG antibodies in newborns to COVID 19 positive mothers were observed . Rate of perinatal complications were higher among newborns of COVID 19 mothers . Evidence against COVID 19 vertical transmis-sion: All tissue or blood specimens and pharyngeal swab qRT-PCR tests among neonates born from COVID 19 mothers were negative . Rate of cross reactivity and false positive results are high in serologic studies .
Conclusions: COVID 19 vertical transmission is a growing health care concern that needs further investigation; however, it is sug-gested to be equipped with PPE on contacts with both COVID 19 pregnant woman and her newborn baby and apply early separation, isolation, testing and close follow up for both mother and child.