A Cross-Sectional Serosurvey of Anti-Orthopoxvirus Antibodies in Central and Western Africa
Siv Aina J. Leendertz,
Daniel Stern,
Dennis Theophil,
Etile Anoh,
Arsène Mossoun,
Grit Schubert,
Lidewij Wiersma,
Chantal Akoua-Koffi,
Emmanuel Couacy-Hymann,
Jean-Jacques Muyembe-Tamfum,
Stomy Karhemere,
Maude Pauly,
Livia Schrick,
Fabian H. Leendertz,
Andreas Nitsche
Affiliations
Siv Aina J. Leendertz
Epidemiology of Highly Pathogenic Microorganisms, Robert Koch Institute, 13353 Berlin, Germany
Daniel Stern
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
Dennis Theophil
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
Etile Anoh
Université Felix Houphouët Boigny, Abidjan BP 1174, Cote D’Ivoire
Arsène Mossoun
Université Felix Houphouët Boigny, Abidjan BP 1174, Cote D’Ivoire
Grit Schubert
Epidemiology of Highly Pathogenic Microorganisms, Robert Koch Institute, 13353 Berlin, Germany
Lidewij Wiersma
Epidemiology of Highly Pathogenic Microorganisms, Robert Koch Institute, 13353 Berlin, Germany
Chantal Akoua-Koffi
Centre de Recherche pour le Développement, Université Alassane Ouattara, Bouaké BP 1174, Cote D’Ivoire
Emmanuel Couacy-Hymann
Laboratoire National D’appui au Développement Agricole/Laboratoire Central de Pathologie Animale, Bingerville BP 206, Cote D’Ivoire
Jean-Jacques Muyembe-Tamfum
Institut National de Recherche Biomédicale, Kinshasa BP 1197, Democratic Republic of the Congo
Stomy Karhemere
Institut National de Recherche Biomédicale, Kinshasa BP 1197, Democratic Republic of the Congo
Maude Pauly
Epidemiology of Highly Pathogenic Microorganisms, Robert Koch Institute, 13353 Berlin, Germany
Livia Schrick
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
Fabian H. Leendertz
Epidemiology of Highly Pathogenic Microorganisms, Robert Koch Institute, 13353 Berlin, Germany
Andreas Nitsche
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
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 Côte d’Ivoire (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.
