Screening of genital fluid for Ebola virus – Authors' reply
Authors: Moses J Soka, Mary J Choi, Lawrence J Purpura, Ute Ströher, Barbara Knust, Pierre Rollin
Journal: The Lancet Global Health (2016)

We welcome the opportunity to respond to the letter by William Fischer and colleagues about our Article.1Soka MJ Choi MJ Baller A et al.Prevention of sexual transmission of Ebola in Liberia through a national semen testing and counselling programme for survivors: an analysis of Ebola virus RNA results and behavioural data.Lancet Glob Health. 2016; 4: 736-743Summary Full Text Full Text PDF PubMed Scopus (74) Google Scholar The main concern expressed in their letter relates to the qRT-PCR assay of the US Centers for Disease Control and Prevention (CDC) used by the Men's Health Screening Program (MHSP) to test semen samples and appears to be based on their “work validating a different diagnostic platform”. However, Fischer and colleagues do not specify which diagnostic platform and, at the time this response was drafted, they had not published the results of this work. Readers should be aware that as of Nov 25, 2016, no assay or diagnostic platform has been validated by the US Food and Drug Administration or other governing bodies for use with seminal fluid specimens. We certainly agree that evaluation and validation of diagnostic assays and platforms are necessary for every biospecimen type. Evaluation of the US CDC qRT-PCR assay on semen has been done, and the results will be submitted for publication shortly (Ströher and colleagues, unpublished data). Furthermore, this assay has been used previously to test semen samples collected from Ebola virus disease survivors in Sierra Leone2Deen GF Knust B Broutet N et al.Ebola RNA persistence in semen of Ebola virus disease survivors—preliminary report.N Engl J Med. 2015; (published online Oct 14.)https://doi.org/10.1056/NEJMoa1511410Crossref Scopus (249) Google Scholar and in the USA.3Uyeki TM Erickson BR Brown S et al.Ebola virus persistence in semen of male survivors.Clin Infect Dis. 2016; 62: 1552-1555Crossref PubMed Scopus (81) Google Scholar To date, more than 800 individuals and more than 1600 semen specimens have been tested using this assay, without evidence of sexual transmission. Fischer and colleagues also raise concerns about the fact that MHSP “only offers testing to men”. As previously stated, MHSP is a public health programme based on the principles outlined in WHO's interim guidelines.4WHOInterim advice on the sexual transmission of the Ebola virus disease.http://www.who.int/reproductivehealth/topics/rtis/ebola-virus-semen/en/Date: 2016Google Scholar The focus of that guidance is preventing sexual transmission of Ebola virus by men and is based on scientific evidence that has shown Ebola virus persistence in semen and sexual transmission of Ebola virus by men to their sexual partners.5Rodriguez LL De Roo A Guimard Y et al.Persistence and genetic stability of Ebola virus during the outbreak in Kikwit, Democratic Republic of the Congo, 1995.J Infect Dis. 1999; 179: S170-S176Crossref PubMed Scopus (253) Google Scholar, 6Mate SE Kugelman JR Nyenswah TG et al.Molecular evidence of sexual transmission of Ebola virus.N Engl J Med. 2015; 373: 2448-2454Crossref PubMed Scopus (308) Google Scholar As of Nov 25, 2016, there have been no reported instances of sexual transmission of Ebola virus by a woman. Nor have there been reports of long-term viral persistence of Ebola virus RNA in vaginal fluids or the detection of infectious virus. Furthermore, no guidance has been released by WHO recommending testing the vaginal fluids of female Ebola virus disease survivors. We agree that further research is warranted in this field. However, in the absence of evidence of a public health risk of female Ebola virus disease survivors transmitting the virus through sex, testing of vaginal fluids in the setting of a public health programme would be premature and could worsen the stigma already faced by Ebola virus disease survivors. We declare no competing interests. Screening of genital fluid for Ebola virusMoses Soka and colleagues (October, 2016)1 describe their semen testing programme for survivors of Ebola virus disease. This programme provides an important service to male survivors of this disease in Liberia; however, we are concerned that the real-time RT-PCR assay used might not be validated for the detection of Ebola virus in semen. Although the assay was granted emergency use authorisation by the US Food and Drug Administration for the detection of Ebola virus RNA in blood, plasma, serum, and urine, Soka and colleagues do not include supporting data for the use of this assay with semen. Full-Text PDF Open AccessPrevention of sexual transmission of Ebola in Liberia through a national semen testing and counselling programme for survivors: an analysis of Ebola virus RNA results and behavioural dataDuration of detection of Ebola virus RNA by real-time RT-PCR varies by individual and might be associated with age. By combining behavioural counselling and laboratory testing, the Men's Health Screening Program helps male Ebola virus disease survivors understand their individual risk and take appropriate measures to protect their sexual partners. Full-Text PDF Open Access