viruses Article Serological Evidence of Filovirus Infection in Nonhuman Primates in Zambia Katendi Changula 1 , Edgar Simulundu 2,3 , Boniface Pongombo Lombe 4,5,6, Eri Nakayama 7 , Hiroko Miyamoto 4, Yuji Takahashi 4, Hirofumi Sawa 2,8,9, Chuma Simukonda 10, Bernard M. Hang’ombe 1 and Ayato Takada 2,4,9,* 1 Department of Paraclinical Studies, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia; [email protected] (K.C.); [email protected] (B.M.H.) 2 Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia; [email protected] (E.S.); [email protected] (H.S.) 3 Macha Research Trust, P.O. Box 630166, Choma 20100, Zambia 4 Division of Global Epidemiology, International Institute for Zoonosis Control, Hokkaido University, Sapporo 001-0020, Japan; [email protected] (B.P.L.); [email protected] (H.M.); [email protected] (Y.T.) 5 Central Veterinary Laboratory of Kinshasa, Kinshasa BP 8842, Democratic Republic of the Congo 6 Faculty of Veterinary Medicine, National Pedagogic University, Kinshasa BP 8815, Democratic Republic of the Congo 7 Department of Virology I, National Institute of Infectious Diseases, Tokyo 162-0052, Japan; [email protected] 8 Division of Molecular Pathobiology, International Institute for Zoonosis Control, Hokkaido University, Sapporo 001-0020, Japan 9 International Collaboration Unit, International Institute for Zoonosis Control, Hokkaido University, Citation: Changula, K.; Simulundu, Sapporo 001-0020, Japan E.; Lombe, B.P.; Nakayama, E.; 10 Department of National Parks and Wildlife, Chilanga 10101, Zambia; [email protected] Miyamoto, H.; Takahashi, Y.; Sawa, * Correspondence: [email protected]; Tel.: +81-11-706-9502 H.; Simukonda, C.; Hang’ombe, B.M.; Takada, A. Serological Evidence of Abstract: Ebolaviruses and marburgviruses are filoviruses that are known to cause severe hemor- Filovirus Infection in Nonhuman rhagic fever in humans and nonhuman primates (NHPs). While some bat species are suspected Primates in Zambia. Viruses 2021, 13, 1283. https://doi.org/10.3390/ to be natural reservoirs of these filoviruses, wild NHPs often act as intermediate hosts for viral v13071283 transmission to humans. Using an enzyme-linked immunosorbent assay, we screened two NHP species, wild baboons and vervet monkeys captured in Zambia, for their serum IgG antibodies Academic Editors: James Strong and specific to the envelope glycoproteins of filoviruses. From 243 samples tested, 39 NHPs (16%) were David Safronetz found to be seropositive either for ebolaviruses or marburgviruses with endpoint antibody titers ranging from 100 to 25,600. Interestingly, antibodies reactive to Reston virus, which is found only in Received: 19 May 2021 Asia, were detected in both NHP species. There was a significant difference in the seropositivity for Accepted: 25 June 2021 the marburgvirus antigen between the two NHP species, with baboons having a higher positive rate. Published: 30 June 2021 These results suggest that wild NHPs in Zambia might be nonlethally exposed to these filoviruses, and this emphasizes the need for continuous monitoring of filovirus infection in wild animals to Publisher’s Note: MDPI stays neutral better understand the ecology of filoviruses and to assess potential risks of outbreaks in humans in with regard to jurisdictional claims in previously nonendemic countries. published maps and institutional affil- iations. Keywords: Ebola virus; ebolavirus; Marburg virus; marburgvirus; filovirus; nonhuman primate; antibody; seroprevalence; Zambia Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. 1. Introduction This article is an open access article distributed under the terms and Filoviruses, including ebolaviruses and marburgviruses, have a non-segmented negative- conditions of the Creative Commons stranded RNA genome and are phylogenetically divided into six genera: Ebolavirus, Mar- Attribution (CC BY) license (https:// burgvirus, Cuevavirus, Dianlovirus, Striavirus, and Thamnovirus. The genus Marburgvirus creativecommons.org/licenses/by/ has a single species with two known viruses (Marburg virus (MARV) and Ravn virus), 4.0/). Viruses 2021, 13, 1283. https://doi.org/10.3390/v13071283 https://www.mdpi.com/journal/viruses Viruses 2021, 13, x FOR PEER REVIEW 2 of 10 Viruses 2021, 13, 1283 Sudan ebolavirus, Tai Forest ebolavirus, Bundibugyo ebolavirus, Reston ebolavirus, 2and of 10 Bombali ebolavirus, represented by Ebola virus (EBOV), Sudan virus (SUDV), Taï Forest virus (TAFV), Bundibugyo virus (BDBV), Reston virus (RESTV), and Bombali virus, respec- buttively six [1]. distinct Of these species filoviruses, are currently MARV, known EB inOV, the SUDV, genus Ebolavirus TAFV, and: Zaire BDBV ebolavirus are known, Su- to be danhuman-pathogenic ebolavirus, Tai Forest filoviruses ebolavirus that, Bundibugyo cause he ebolavirusmorrhagic, Reston fever, ebolavirus namely ,Marburg and Bombali virus dis- ebolavirusease (MVD), represented and Ebola by Ebolavirus virus disease (EBOV), (EVD) Sudan in humans virus (SUDV), and nonhuman Taï Forest virus primates (TAFV), (NHPs) Bundibugyo[2]. RESTV causes virus (BDBV), disease Reston in NHPs virus and (RESTV), has also and been Bombali found virus, in pigs respectively [3,4]. Although [1]. it is Ofnot these known filoviruses, to cause MARV, disease EBOV, in humans, SUDV, there TAFV, ha andve been BDBV reports are known of seroconversion to be human- in hu- pathogenicmans after filoviruses contact with that RESTV-infected cause hemorrhagic NHPs fever, or namely pigs Marburg[3,4]. virus disease (MVD) and Ebola virus disease (EVD) in humans and nonhuman primates (NHPs) [2]. RESTV NHPs are known to be highly susceptible to filovirus infection. In some of the previ- causes disease in NHPs and has also been found in pigs [3,4]. Although it is not known ous outbreaks of EVD, large die-offs of NHPs have been recorded prior to or during the to cause disease in humans, there have been reports of seroconversion in humans after contactoutbreaks with [5–8]. RESTV-infected In addition, NHPs NHPs or pigs have [3 ,been4]. implicated as a source of human infection in someNHPs outbreaks, are known with to bethe highlyindex cases susceptible having to handled filovirus infected infection. NH InP carcasses some of the [7,9]. The previoussource of outbreaks infection of in EVD, the largefirst die-offsever recorded of NHPs outbreak have been of recorded a filovirus prior disease, to or during MVD, was theAfrican outbreaks green [5 –monkeys8]. In addition, [10]. NHPsAntibodies have been to vari implicatedous filoviruses as a source have of human been detected infection in sev- ineral some NHP outbreaks, species, with both the in indexareas casesof previously having handled reported infected outbreaks NHP carcassesand those [7 that,9]. The had never sourcereported of infectionan outbreak in the [11–16]. first ever recorded outbreak of a filovirus disease, MVD, was AfricanThe green aim monkeys of this study [10]. Antibodies was to investigate to various the filoviruses possible have exposure been detected of NHPs in several to filoviruses NHPin Zambia, species, where both in neither areas of an previously EVD nor reported an MVD outbreaks outbreak and has those ever that been had recorded. never We reported an outbreak [11–16]. screened 243 serum samples collected from NHPs in Zambia for the detection of filovirus- The aim of this study was to investigate the possible exposure of NHPs to filoviruses in specific IgG. There was evidence of previous exposure to filoviruses in these NHP popu- Zambia, where neither an EVD nor an MVD outbreak has ever been recorded. We screened 243lations. serum samples collected from NHPs in Zambia for the detection of filovirus-specific IgG. There was evidence of previous exposure to filoviruses in these NHP populations. 2. Materials and Methods 2.2.1. Materials Animals and and Methods Serum Samples 2.1. Animals and Serum Samples Serum samples were previously obtained from 125 (41 female and 84 male) yellow Serum samples were previously obtained from 125 (41 female and 84 male) yellow baboons (Papio cynocephalus) and 118 (33 female and 85 male) vervet monkeys (Chlorocebus baboons (Papio cynocephalus) and 118 (33 female and 85 male) vervet monkeys (Chlorocebus pygerythruspygerythrus) in) in game game management management areas areas in the in Mfuwethe Mfuwe region region (Eastern (Eastern Province, Province, Zambia) Zambia) andand Livingstone Livingstone (Southern (Southern Province, Province, Zambia) Zambia) (Figure (Figure1) between 1) between 2008 and 2008 2010 and with 2010 the with the permissionpermission (certificate (certificate no. no. 2604) 2604) of of the the Zambia Zambia Wildlife Wildlife Authority, Authority, which which is mandated is mandated by bythe the Zambian Zambian government government to to control control the the larg largee numbers ofof wildwild NHPs NHPs [ 17[17–19].–19]. Serum Serum sam- samplesples were were stored stored at − at80− °80C ◦untilC until they they were were used. used. The The residual residual serum serum samples samples were were used in usedthe present in the present study. study. Tanzania Democratic Republic of the Congo Mfuwe Malawi Angola Zambia Lusaka Mozambique Livingstone Zimbabwe Namibia Botswana FigureFigure 1. 1.Map Map of of Zambia Zambia showing showing the the location location of the of sampling the sampling sites (Mfuwe sites (Mfuwe and Livingstone). and Livingstone). Viruses 2021, 13, 1283