Table 2.
Characteristics of the included studies.
| Authors | Year | Country | Type of Study | Cohort/Outbreak Time | Cohort/Outbreak Location | Study Population | Clade | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Total | Confirmed | Probable | Suspected | Primary Cases | Secondary Cases | Unknown | |||||||
| Johnston et al. [45] | 2014 | USA | Short communication | 2005–2007 | DRC | 19 | 19 | 0 | 0 | 0 | 0 | 19 | NA |
| McCollum et al. [46] | 2015 | USA | Case series | November 2011 | Kivu, DRC | 6 | 3 | 0 | 3 | 0 | 0 | 6 | NA |
| Nolen et al. [15] | 2016 | DRC | Cross-sectional | December 2013 | Bokungu, DRC | 63 | 20 | 19 | 24 | 0 | 0 | 63 | NA |
| Reynolds et al. [47] | 2016 | USA | Brief report | 2013 | DRC | 7 | 2 | 0 | 5 | 0 | 0 | 7 | NA |
| Hoff et al. [16] | 2017 | USA | Cross-sectional | 2006 | DRC | 1158 | 785 (633 MPX only + 152 MPX/VZV) |
0 | 373 | 0 | 0 | 1158 | NA |
| Mbala et al. [48] | 2017 | USA | Brief report | March 2007 | DRC | 4 | 4 | 0 | 0 | 0 | 0 | 4 | NA |
| Osadebe et al. [17] | 2017 | USA | Cross-sectional | 2009–2014 | DRC | 752 | 333 | 0 | 419 | 0 | 0 | 333 | NA |
| Nakoune et al. [49] | 2017 | The Central African Republic | Brief report | December 2015–January 2016 | Mbomou province, The Central African Republic | 10 | 3 | 7 | 0 | 1 | 2 | 7 | Zaire genotype strain |
| Kalthan et al. [50] | 2018 | The Central African Republic | Cross-sectional | August 2016–October 2016 | Africa | 26 | 3 | 0 | 23 | 0 | 23 | 3 | NA |
| Yinka-Ogunleye et al. [51] | 2018 | Nigeria | Letter | November 2017 | Nigeria | 42 | 42 | 0 | 0 | 0 | 0 | 42 | West African |
| Vaughan et al. [52] | 2018 | UK | Rapid communication | September 2018 | UK | 2 | 2 | 0 | 0 | 2 | 0 | 0 | West African (Nigerian) |
| Doshi et al. [18] | 2019 | USA | Cross-sectional | November 2005–November 2007 | Sankuru Province, DRC | 223 | 223 | 0 | 0 | 223 | 0 | 0 | NA |
| Raynolds et al. [53] | 2019 | USA | Letter | March 2014, March 2017 | Kpetema town and Pujehun district, Sierra Leone | 2 | 2 | 0 | 0 | 1 | 0 | 1 | West African |
| Doshi et al. [19] | 2019 | USA | Cross-sectional | January 2017–April 2017 | 3 Enyelle, 15 Dongou, 4 Impfondo | 22 | 7 | 15 | 0 | 2 | 11 | 9 | NA |
| Ye et al. [54] | 2019 | China | Letter | March 2017 | Kpaku village, Pujehun district, Sierra Leone | 1 | 1 | 0 | 0 | 1 | 0 | 0 | West African |
| Yinka-Ogunleye et al. [20] | 2019 | Nigeria | Cross-sectional | 2017–2018 | Nigeria | 122 | 118 | 4 | 0 | 86 | 36 | 0 | West African |
| Besombes et al. [55] | 2019 | France | Letter | September 2018, October 2018 | Lobaya, Central African Republic | 6 | 6 | 0 | 0 | 1 | 5 | 0 | NA |
| Ogoina et al. [21] | 2019 | Nigeria | Cross-sectional | September 2022 | Bayelsa state, Nigeria | 21 | 18 | 3 | 0 | 0 | 0 | 21 | West African |
| Hughes et al. [22] | 2020 | USA | Cross-sectional | September 2009 | DRC | 1271 | 534 (400 MPX only + 134 MPX/VZV) |
0 | 737 | 0 | 0 | 1271 | NA |
| Ogoina et al. [56] | 2020 | Nigeria | Brief report | September 2017–December 2018 | Nigeria | 40 | 40 | 0 | 0 | 0 | 0 | 40 | NA |
| Whitehouse et al. [23] | 2021 | USA | Cross-sectional | 2011–2015 | DRC | 1057 | 1057 | 0 | 0 | 309 | 279 | 469 | NA |
| Hobson et al. [57] | 2021 | UK | Rapid communication | May 2021 | UK | 3 | 3 | 0 | 0 | 0 | 2 | 1 | West African |
| Ng et al. [58] | 2022 | Singapore | Correspondence | April 2019 | Singapore | 1 | 1 | 0 | 0 | 1 | 0 | 0 | NA |
| Besombes et al. [24] | 2022 | France | Cross-sectional | 2001–2021 | Central African Republic | 327 | 99 | 0 | 61 suspected, 167 contacts | 0 | 44 | 55 | NA |
| Pittman et al. [59] | 2022 | USA | Cross-sectional | March 2007–August 2011 | Democratic Republic of the Congo | 216 | 216 | 0 | 0 | 0 | 82 | 134 | NA |
| Adler et al. [26] | 2022 | UK | Cross-sectional | August 2018–September 2021 | UK | 7 | 7 | 0 | 0 | 0 | 3 | 4 | NA |
| Tarín-Vicente et al. [27] | 2022 | Spain | Cross-sectional | 2022 | Spain | 181 | 181 | 0 | 0 | 0 | 181 | 0 | West African |
| Vallejo-Plaza et al. [60] | 2022 | Spain | Rapid communication | 26 April 2022–21 November 2022 | Spain | 7393 | 7393 | 0 | 0 | 0 | 4986 | 2407 | NA |
| Thornhill et al. [61] | 2022 | UK | Case series | 27 April 2022–24 June 2022 | United States, Canada, Mexico, Argentina, Netherlands, Belgium, United Kingdom, Portugal, Spain, France, Switzerland, Italy, Germany, Denmark, Australia, Israel | 528 | 528 | 0 | 0 | 0 | 511 | 17 | NA |
| Perez-Duque et al. [62] | 2022 | Portugal | Rapid communication | 29 April–23 May 2022 | Portugal | 27 | 27 | 0 | 0 | 0 | 0 | 27 | West African |
| Angelo et al. [28] | 2022 | USA | Cross-sectional | May 2022–July 2022 | 19 countries (Spain (35% of 226 patients), Canada (29% of 226 patients), Germany, France, Belgium, Netherlands, Portugal, Sweden, Romania, USA, Israel, South Africa, UK, Denmark, Argentina) | 226 | 226 | 0 | 0 | 0 | 78 | 117 | NA |
| Betancort-Plata et al. [29] | 2022 | Spain | Cross-sectional | May 2022–July 2022 | Spain | 42 | 42 | 0 | 0 | 0 | 1 | 41 | NA |
| Rodríguez-Cuadrado et al. [63] | 2022 | Spain | Case series | May 2022–July 2022 | Spain | 20 | 20 | 0 | 0 | 0 | 0 | 20 | NA |
| Caria et al. [30] | 2022 | Portugal | Cross-sectional | May–July 2022 | Portugal | 41 | 41 | 0 | 0 | 0 | 37 | 4 | NA |
| Vanhamel et al. [31] | 2022 | Belgium | Cross-sectional | May 2022–Jun 2022 | Belgium | 139 | 139 | 0 | 0 | 66 | 28 | 45 | NA |
| Fink et al. [32] |
2022 | UK | Cross-sectional | 6 May–August 2022 | UK | 156 | 156 | 0 | 0 | 0 | 0 | 156 | NA |
| Thornhill et al. [64] | 2022 | UK | Case series | 11 May 2022–4 October 2022 | 15 countries and three WHO regions; 65 regions of America, 68 European regions, 3 African regions | 136 | 126 | 10 | 0 | 0 | 118 | 18 | NA |
| Patel et al. [25] | 2022 | UK | Case series | 13 May 2022–1 July 2022 | UK | 197 | 197 | 0 | 0 | 0 | 41 | 156 | NA |
| Girometti et al. [33] | 2022 | UK | Cross-sectional | 14–25 May 2022 |
UK | 54 | 54 | 0 | 0 | 0 | 2 | 52 | NA |
| Vivancos-Gallego et al. [65] | 2022 | Spain | Brief report | 16 May 2022–Jun 2022 | Spain | 25 | 25 | 0 | 0 | 0 | 0 | 25 | West African |
| Sheffer et al. [66] | 2022 | Israel | Short communication | 16 May 2022–13 September 2022 | Israel | 203 | 203 | 0 | 0 | 0 | 198 | 5 | NA |
| Antinori et al. [67] | 2022 | Italy | Case series | 17–22 May 2022 | Italy | 4 | 4 | 0 | 0 | 0 | 0 | 4 | NA |
| Orviz et al. [34] | 2022 | Spain | Cross-sectional | 18 May 2022–first weeks of June 2022 | Spain | 48 | 48 | 0 | 0 | 0 | 7 | 41 | West African |
| Hoffmann et al. [35] | 2022 | Germany | Cross-sectional | 19 May 2022–June 2022 | Germany | 301 | 301 | 0 | 0 | 0 | 0 | 301 | NA |
| Cobos et al. [36] | 2022 | Spain | Cross-sectional | 19 May–7 June 2022 | Spain | 30 | 30 | 0 | 0 | 0 | 30 | 0 | NA |
| Hoffmann et al. [37] | 2022 | Germany | Cross-sectional | 19 May 2022–30 June 2022 | Germany | 546 | 546 | 0 | 0 | 0 | 0 | 546 | NA |
| Van Ewijk et al. [38] | 2022 | Netherlands | Cross-sectional | 20 May 2022–8 August 2022 | Netherlands | 1928 | 1000 | 122 | 806 | 0 | 865 | 135 | NA |
| Mailhe et al. [39] | 2022 | France | Cross-sectional | 21 May 2022–5 July 2022 | France | 264 | 264 | 0 | 0 | 0 | 112 | 152 | NA |
| Núñez et al. [40] | 2022 | Mexico | Cross-sectional | 24 May 2022–5 September 2022 | Mexico | 565 | 565 | 0 | 0 | 0 | 104 | 461 | West African |
| Maldonado-Barrueco et al. [68] | 2023 | Spain | Case series | 26 May 2022–31 December 2022 | Spain | 30 | 30 | 0 | 0 | 0 | 0 | 30 | NA |
| Catala et al. [41] | 2022 | Spain | Cross-sectional | 28 May–14 July 2022 | Spain | 185 | 185 | 0 | 0 | 0 | 67 | 118 | NA |
| Relhan et al. [69] | 2022 | India | Short communication | Jun 2022–Aug 2022 | India | 5 | 5 | 0 | 0 | 0 | 1 | 4 | NA |
| Cassir et al. [42] | 2022 | France | Cross-sectional | 4 June 2022–31 August 2022 | France | 136 | 136 | 0 | 0 | 0 | 28 | 108 | NA |
| Pascom et al. [70] | 2022 | Brazil | Cross-sectional | 7 Jun 2022–1 Oct 2022 | Brazil | 8176 | 7992 | 175 | 0 | 0 | 0 | 8176 | NA |
| Martins-Filho et al. [71] | 2022 | Brazil | Letter | 9 June 2022–23 November 2022 | Brazil | 9100 | 9100 | 0 | 0 | 0 | 0 | 1457 | NA |
| Wong et al. [72] | 2022 | USA | Case seies | 13 Jun 2022–11 Jul 2022 | USA | 7 | 7 | 0 | 0 | 0 | 7 | 0 | NA |
| Suner et al. [43] | 2022 | Spain | Cross-sectional | 28 June 2022, and 22 September 2022 | Spain | 77 | 77 | 0 | 0 | 0 | 0 | 77 | NA |
| Cash-Goldwasser et al. [73] | 2022 | USA | Case series | July–September 2022 | USA | 5 | 5 | 0 | 0 | 0 | 0 | 5 | NA |
| Ciccarese et al. [74] | 2022 | Italy | Case series | 1 July–31 August 2022 | Italy | 16 | 16 | 0 | 0 | 0 | 16 | 0 | NA |
| Aguilera-Alonso et al. [75] | 2022 | Spain | Correspondence | Until August 2022 | Spain | 16 | 16 | 0 | 0 | 0 | 15 | 1 | NA |
| Gnanaprakasam et al. [76] | 2022 | USA | Letter | Summer 2022 | USA | 23 | 23 | 0 | 0 | 0 | 0 | 23 | NA |
| Choudhury et al. [77] | 2022 | Germany | Letter | Until September 2022 | Germany | 179 | 179 | 0 | 0 | 0 | 150 | 29 | NA |
| Srichawla et al. [78] | 2022 | USA | Case series | NA | USA | 9 | 9 | 0 | 0 | 0 | 7 | 2 | West African |
| Maldonado et al. [44] | 2023 | Peru | Cross-sectional | 1 July 2022–3 September 2022 | Peru | 205 | 205 | 0 | 0 | 0 | 17 | 188 | NA |
| Rekik et al. [79] | 2023 | France | Case series | 6–11 July 2022 | France | 20 | 20 | 0 | 0 | 0 | 9 | 11 | NA |
| Prasad et al. [80] | 2023 | USA | Case series | 4 August 2022–13 November 2022 | 13 countries in North America, Europe, Asia, Latin America and the Caribbean, and Africa | 101 | 101 | 0 | 0 | 0 | 32 | 69 | NA |
| Assiri et al. [81] | 2023 | Saudi Arabia | Case series | NA | Saudi Arabia | 7 | 7 | 0 | 0 | 0 | 7 | 0 | NA |
NA: not available.