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Sexual Transmission of American Trypanosomes from Males and Females to Naive Mates
Published on: January 27, 2019
Evaluating vertical transmission of sexually transmitted infections to newborns
Dinamene Oliveira1, João Piedade2, Rita Castro2
1Huíla Health Centre, Girassol Clinic, Lubango, Huíla, Angola. odinamene@gmail.com.
Introduction:
Sexually transmitted infections are among the most frequent infections affecting pregnant women. We assessed the transmission of hepatitis B virus, human immunodeficiency virus type 1 and Treponema pallidum to newborns from infected parturients.
Methodology:
An observational, cross-sectional, analytical facility-based survey was conducted among 57 newborns in Irene Neto Maternity, Lubango city, Huíla province, Angola. Hepatitis B virus DNA molecular identification was done through nested PCR. Human immunodeficiency virus type 1 proviral DNA detection was carried out by two successive nested PCRs. Real-time PCR was performed to examine the presence of T. pallidum DNA. Amplicons from PCR positive samples were sequenced for identity search and genotype assignment.
Results:
Hepatitis B virus DNA genotype E was detected in 3/41 (7.3%) newborns from HBsAg (hepatitis B surface antigen) positive mothers. To analyse the association between mothers HBeAg (hepatitis B e antigen) positivity and hepatitis B virus vertical transmission to newborns, a Fisher's exact test was performed, showing a highly significant association (p = 0.006). Human immunodeficiency virus type 1 provirus or T. pallidum DNA was not detected in any newborn.
Conclusions:
To prevent hepatitis B virus vertical transmission in Angola it is important to promote universal antenatal screening, expanding hepatitis B virus markers (viral load and/or HBeAg), risk-based infected mothers' antiviral therapy and newborn passive immunoprophylaxis.
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