{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,27]],"date-time":"2026-09-27T14:58:44Z","timestamp":1790521124196,"version":"4.1.0"},"reference-count":47,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2017,9,29]],"date-time":"2017-09-29T00:00:00Z","timestamp":1506643200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Since the eradication of smallpox and the subsequent discontinuation of the worldwide smallpox vaccination program, other Orthopoxviruses beside Variola virus have been increasingly representing a risk to human health. To investigate the extent of natural contact with Orthopoxviruses and possible demographic risk factors for such an exposure, we performed a cross-sectional serosurvey of anti-Orthopoxvirus IgG antibodies in West and Central Africa. To this end, people living in forest regions in C\u00f4te d\u2019Ivoire (CIV, n = 737) and the Democratic Republic of the Congo (COD, n = 267) were assigned into groups according to their likely smallpox vaccination status. The overall prevalence of anti-Orthopoxvirus antibodies was 51% in CIV and 60% in COD. High rates of seropositivity among the vaccinated part of the population (80% in CIV; 96% COD) indicated a long-lasting post vaccination immune response. In non-vaccinated participants, seroprevalences of 19% (CIV) and 26% (COD) indicated regular contact with Orthopoxviruses. Multivariate logistic regression revealed that the antibody level in the vaccinated part of the population was higher in COD than in CIV, increased with age and was slightly higher in females than males. In the unvaccinated part of the population none of these factors influenced antibody level significantly. In conclusion, our results confirm expectedly high anti-Orthopoxvirus seroprevalences in previously smallpox-vaccinated people living in CIV and the COD but more unexpectedly imply regular contact with Orthopoxviruses both in Western and Central Africa, even in the absence of recognized outbreaks.<\/jats:p>","DOI":"10.3390\/v9100278","type":"journal-article","created":{"date-parts":[[2017,9,29]],"date-time":"2017-09-29T12:24:04Z","timestamp":1506687844000},"page":"278","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":29,"title":["A Cross-Sectional Serosurvey of Anti-Orthopoxvirus Antibodies in Central and Western Africa"],"prefix":"10.3390","volume":"9","author":[{"given":"Siv","family":"Leendertz","sequence":"first","affiliation":[{"name":"Epidemiology of Highly Pathogenic Microorganisms, Robert Koch Institute, 13353 Berlin, Germany"},{"name":"Department of Infectious Disease Epidemiology, Robert Koch Institute, 13353 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9057-4283","authenticated-orcid":false,"given":"Daniel","family":"Stern","sequence":"additional","affiliation":[{"name":"Centre for Biological Threats and Special Pathogens ZBS 1, Highly Pathogenic Viruses Centre for Biological Threats and Special Pathogens, Robert Koch Institute, 13353 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dennis","family":"Theophil","sequence":"additional","affiliation":[{"name":"Centre for Biological Threats and Special Pathogens ZBS 1, Highly Pathogenic Viruses Centre for Biological Threats and Special Pathogens, Robert Koch Institute, 13353 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Etile","family":"Anoh","sequence":"additional","affiliation":[{"name":"Universit\u00e9 Felix Houphou\u00ebt Boigny, Abidjan BP 1174, Cote D\u2019Ivoire"},{"name":"Centre de Recherche pour le D\u00e9veloppement, Universit\u00e9 Alassane Ouattara, Bouak\u00e9 BP 1174, Cote D\u2019Ivoire"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ars\u00e8ne","family":"Mossoun","sequence":"additional","affiliation":[{"name":"Universit\u00e9 Felix Houphou\u00ebt Boigny, Abidjan BP 1174, Cote D\u2019Ivoire"},{"name":"Laboratoire National D\u2019appui au D\u00e9veloppement Agricole\/Laboratoire Central de Pathologie Animale, Bingerville BP 206, Cote D\u2019Ivoire"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Grit","family":"Schubert","sequence":"additional","affiliation":[{"name":"Epidemiology of Highly Pathogenic Microorganisms, Robert Koch Institute, 13353 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lidewij","family":"Wiersma","sequence":"additional","affiliation":[{"name":"Epidemiology of Highly Pathogenic Microorganisms, Robert Koch Institute, 13353 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chantal","family":"Akoua-Koffi","sequence":"additional","affiliation":[{"name":"Centre de Recherche pour le D\u00e9veloppement, Universit\u00e9 Alassane Ouattara, Bouak\u00e9 BP 1174, Cote D\u2019Ivoire"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emmanuel","family":"Couacy-Hymann","sequence":"additional","affiliation":[{"name":"Laboratoire National D\u2019appui au D\u00e9veloppement Agricole\/Laboratoire Central de Pathologie Animale, Bingerville BP 206, Cote D\u2019Ivoire"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jean-Jacques","family":"Muyembe-Tamfum","sequence":"additional","affiliation":[{"name":"Institut National de Recherche Biom\u00e9dicale, Kinshasa BP 1197, Democratic Republic of the Congo"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stomy","family":"Karhemere","sequence":"additional","affiliation":[{"name":"Institut National de Recherche Biom\u00e9dicale, Kinshasa BP 1197, Democratic Republic of the Congo"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maude","family":"Pauly","sequence":"additional","affiliation":[{"name":"Epidemiology of Highly Pathogenic Microorganisms, Robert Koch Institute, 13353 Berlin, Germany"},{"name":"Department of Infection and Immunity, Luxembourg Institute of Health, 4354 Esch-sur-Alzette, Luxembourg"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Livia","family":"Schrick","sequence":"additional","affiliation":[{"name":"Centre for Biological Threats and Special Pathogens ZBS 1, Highly Pathogenic Viruses Centre for Biological Threats and Special Pathogens, Robert Koch Institute, 13353 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fabian","family":"Leendertz","sequence":"additional","affiliation":[{"name":"Epidemiology of Highly Pathogenic Microorganisms, Robert Koch Institute, 13353 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andreas","family":"Nitsche","sequence":"additional","affiliation":[{"name":"Centre for Biological Threats and Special Pathogens ZBS 1, Highly Pathogenic Viruses Centre for Biological Threats and Special Pathogens, Robert Koch Institute, 13353 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2017,9,29]]},"reference":[{"key":"ref_1","unstructured":"Damon, I.K. 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