Althaus Christian L., PD PhD

Head of Research Group

Research - INPUT – Interfaculty Platform for Data and Computational Science

+41 31 684 56 71
Postal Address
Mittelstrasse 43, 3012 Bern

I use mathematical modeling and data science to tackle the public health challenges of the 21st century.PD Dr. Christian L. Althaus is a computational epidemiologist and head of the Interfaculty Platform for Data and Computational Science (INPUT) at the Institute of Social and Preventive Medicine (ISPM) at the University of Bern at the University of Bern, Switzerland. He is also a member of the directorate of ISPM.

After studying biology at ETH Zurich (Switzerland), Dr. Althaus received his doctorate in theoretical biology at Utrecht University (The Netherlands). In 2017, he qualified as a university lecturer at the University of Bern medical faculty in the field of infectious disease epidemiology. He uses mathematical and computational modeling in combination with data analyses to investigate how the health of populations and the population biology of infectious diseases are affected by environmental changes and public health interventions. Dr. Althaus is an expert for emerging infectious diseases and has made major contributions to the better understanding of the transmission dynamics of Ebola, MERS, and COVID-19. He is a member of the Multidisciplinary Center for Infectious Diseases (MCID) at the University of Bern and served as a member of the Swiss National COVID-19 Science Task Force in 2020.

Visit for more information on my research.

Education and Academic Degrees

  • University of Bern, Bern, Switzerland
    • Habilitation, Epidemiology of infectious diseases, 2017
  • Utrecht University, Utrecht, The Netherlands
    • Ph.D., Theoretical Biology, 2005 - 2009
  • ETH Zürich, Zürich, Switzerland
    • Dipl. Natw. ETH, Biology, 1998 - 2004
  • Humboldt-Universität zu Berlin, Berlin, Germany
    • Erasmus exchange programme, 2002

Academic Appointments

  • Institute of Social and Preventive Medicine, University of Bern, Switzerland
    • Member of Directorate, 2020 -
    • Member of Management Board, 2017 - 2020
    • Head of Research Group, 2014 -
    • SNSF Ambizione Research Fellow, 2011 - 2014
    • Postdoctoral Research Fellow, 2009 - 2011
  • Theoretical Biology & Bioinformatics, Utrecht University, Utrecht, The Netherlands
    • Research Assistant, 2005 - 2009
  • Institute for Ecology & Evolution, ETH Zurich, Zurich, Switzerland
    • Research Assistant, 2004 - 2005

See PubMed or Google Scholar for a complete list of publications and preprints.

Publication list (updated: 30 Jun 2022)

  1. Emergence of SARS-CoV-2 Omicron lineages BA.4 and BA.5 in South Africa. Tegally H, Moir M, Everatt J, Giovanetti M, Scheepers C, Wilkinson E, Subramoney K, Makatini Z, Moyo S, Amoako DG, Baxter C, Althaus CL, Anyaneji UJ, Kekana D, Viana R, Giandhari J, Lessells RJ, Maponga T, Maruapula D, Choga W, Matshaba M, Mbulawa MB, Msomi N; NGS-SA consortium, Naidoo Y, Pillay S, Sanko TJ, San JE, Scott L, Singh L, Magini NA, Smith-Lawrence P, Stevens W, Dor G, Tshiabuila D, Wolter N, Preiser W, Treurnicht FK, Venter M, Chiloane G, McIntyre C, O'Toole A, Ruis C, Peacock TP, Roemer C, Pond SLK, Williamson C, Pybus OG, Bhiman JN, Glass A, Martin DP, Jackson B, Rambaut A, Laguda-Akingba O, Gaseitsiwe S, von Gottberg A, de Oliveira T. Nat Med. 2022 Jun 27.
  2. Assessing real-world vaccine effectiveness against severe forms of SARS-CoV-2 infection: an observational study from routine surveillance data in Switzerland. Anderegg N, Althaus CL, Colin S, Hauser A, Laube A, Mäusezahl M, Wagner M, Zaffora B, Riou J. Swiss Med Wkly. 2022 Apr 19;152:w30163.
  3. Replacement of the Gamma by the Delta variant in Brazil: Impact of lineage displacement on the ongoing pandemic.. Giovanetti M, Fonseca V, Wilkinson E, Tegally H, San EJ, Althaus CL, Xavier J, Nanev Slavov S, Viala VL, Ranieri Jerônimo Lima A, Ribeiro G, Souza-Neto JA, Fukumasu H, Lehmann Coutinho L, Venancio da Cunha R, Freitas C, Campelo de A E Melo CF, Navegantes de Araújo W, Do Carmo Said RF, Almiron M, de Oliveira T, Coccuzzo Sampaio S, Elias MC, Covas DT, Holmes EC, Lourenço J, Kashima S, de Alcantara LCJ. Virus Evol. 2022 Mar 18;8(1):veac024.
  4. Rapid epidemic expansion of the SARS-CoV-2 Omicron variant in southern Africa. Viana R, Moyo S, Amoako DG, Tegally H, Scheepers C, Althaus CL, Anyaneji UJ, Bester PA, Boni MF, Chand M, Choga WT, Colquhoun R, Davids M, Deforche K, Doolabh D, du Plessis L, Engelbrecht S, Everatt J, Giandhari J, Giovanetti M, Hardie D, Hill V, Hsiao NY, Iranzadeh A, Ismail A, Joseph C, Joseph R, Koopile L, Kosakovsky Pond SL, Kraemer MUG, Kuate-Lere L, Laguda-Akingba O, Lesetedi-Mafoko O, Lessells RJ, Lockman S, Lucaci AG, Maharaj A, Mahlangu B, Maponga T, Mahlakwane K, Makatini Z, Marais G, Maruapula D, Masupu K, Matshaba M, Mayaphi S, Mbhele N, Mbulawa MB, Mendes A, Mlisana K, Mnguni A, Mohale T, Moir M, Moruisi K, Mosepele M, Motsatsi G, Motswaledi MS, Mphoyakgosi T, Msomi N, Mwangi PN, Naidoo Y, Ntuli N, Nyaga M, Olubayo L, Pillay S, Radibe B, Ramphal Y, Ramphal U, San JE, Scott L, Shapiro R, Singh L, Smith-Lawrence P, Stevens W, Strydom A, Subramoney K, Tebeila N, Tshiabuila D, Tsui J, van Wyk S, Weaver S, Wibmer CK, Wilkinson E, Wolter N, Zarebski AE, Zuze B, Goedhals D, Preiser W, Treurnicht F, Venter M, Williamson C, Pybus OG, Bhiman J, Glass A, Martin DP, Rambaut A, Gaseitsiwe S, von Gottberg A, de Oliveira T. Nature. 2022 Mar;603(7902):679-686.
  5. The epidemic volatility index, a novel early warning tool for identifying new waves in an epidemic. Kostoulas P, Meletis E, Pateras K, Eusebi P, Kostoulas T, Furuya-Kanamori L, Speybroeck N, Denwood M, Doi SAR, Althaus CL, Kirkeby C, Rohani P, Dhand NK, Peñalvo JL, Thabane L, BenMiled S, Sharifi H, Walter SD. Sci Rep. 2021 Dec 10;11(1):23775.
  6. A public health strategy for SARS-CoV-2, grounded in science, should guide Swiss schools through the coming winter. Keiser O, Agoritsas T, Althaus CL, Azman AS, de Quervain D, Flahault A, Goutaki M, Merglen A, Eckerle I. Swiss Med Wkly. 2021 Oct 14;151:w30086.
  7. Quantification of the spread of SARS-CoV-2 variant B.1.1.7 in Switzerland. Chen C, Nadeau SA, Topolsky I, Manceau M, Huisman JS, Jablonski KP, Fuhrmann L, Dreifuss D, Jahn K, Beckmann C, Redondo M, Noppen C, Risch L, Risch M, Wohlwend N, Kas S, Bodmer T, Roloff T, Stange M, Egli A, Eckerle I, Kaiser L, Denes R, Feldkamp M, Nissen I, Santacroce N, Burcklen E, Aquino C, de Gouvea AC, Moccia MD, Grüter S, Sykes T, Opitz L, White G, Neff L, Popovic D, Patrignani A, Tracy J, Schlapbach R, Dermitzakis ET, Harshman K, Xenarios I, Pegeot H, Cerutti L, Penet D, Blin A, Elies M, Althaus CL, Beisel C, Beerenwinkel N, Ackermann M, Stadler T. Epidemics. 2021 Dec;37:100480.
  8. Drivers of HIV-1 drug resistance to non-nucleoside reverse-transcriptase inhibitors (NNRTIs) in nine southern African countries: a modelling study. Riou J, Dupont C, Bertagnolio S, Gupta RK, Kouyos RD, Egger M, L Althaus C. BMC Infect Dis. 2021 Oct 7;21(1):1042.
  9. Socioeconomic position and the COVID-19 care cascade from testing to mortality in Switzerland: a population-based analysis. Riou J, Panczak R, Althaus CL, Junker C, Perisa D, Schneider K, Criscuolo NG, Low N, Egger M. Lancet Public Health. 2021 Jul 9:S2468-2667(21)00160-2.
  10. Quantifying superspreading for COVID-19 using Poisson mixture distributions. Kremer C, Torneri A, Boesmans S, Meuwissen H, Verdonschot S, Vanden Driessche K, Althaus CL, Faes C, Hens N. Sci Rep. 2021 Jul 8;11(1):14107.
  11. Spread of a SARS-CoV-2 variant through Europe in the summer of 2020. Hodcroft EB, Zuber M, Nadeau S, Vaughan TG, Crawford KHD, Althaus CL, Reichmuth ML, Bowen JE, Walls AC, Corti D, Bloom JD, Veesler D, Mateo D, Hernando A, Comas I, González-Candelas F; SeqCOVID-SPAIN consortium, Stadler T, Neher RA. Nature. 2021 Jun 7.
  12. A Data-Driven Simulation of the Exposure Notification Cascade for Digital Contact Tracing of SARS-CoV-2 in Zurich, Switzerland. Menges D, Aschmann HE, Moser A, Althaus CL, von Wyl V. JAMA Netw Open. 2021 Apr 1;4(4):e218184.
  13. Early evidence of effectiveness of digital contact tracing for SARS-CoV-2 in Switzerland. Salathé M, Althaus C, Anderegg N, Antonioli D, Ballouz T, Bugnon E, Čapkun S, Jackson D, Kim SI, Larus J, Low N, Lueks W, Menges D, Moullet C, Payer M, Riou J, Stadler T, Troncoso C, Vayena E, von Wyl V. Swiss Med Wkly. 2020 Dec 16;150:w20457.
  14. The approximately universal shapes of epidemic curves in the Susceptible-Exposed-Infectious-Recovered (SEIR) model. Heng K, Althaus CL. Sci Rep. 2020 Nov 9;10(1):19365.
  15. COVID-19 infectivity profile correction. Ashcroft P, Huisman JS, Lehtinen S, Bouman JA, Althaus CL, Regoes RR, Bonhoeffer S.J. Swiss Med Wkly. 2020 Aug 5;150:w20336.
  16. Estimation of SARS-CoV-2 mortality during the early stages of an epidemic: A modeling study in Hubei, China, and six regions in Europe. Hauser A, Counotte MJ, Margossian CC, Konstantinoudis G, Low N, Althaus CL, Riou J. PLoS Med. 2020 Jul 28;17(7):e1003189.
  17. Dynamic interventions to control COVID-19 pandemic: a multivariate prediction modelling study comparing 16 worldwide countries. Chowdhury R, Heng K, Shawon MSR, Goh G, Okonofua D, Ochoa-Rosales C, Gonzalez-Jaramillo V, Bhuiya A, Reidpath D, Prathapan S, Shahzad S, Althaus CL, Gonzalez-Jaramillo N, Franco OH; Global Dynamic Interventions Strategies for COVID-19 Collaborative Group. Eur J Epidemiol. 2020 May;35(5):389-399.
  18. Understanding the spread of de novo and transmitted macrolide-resistance in Mycoplasma genitalium. Cadosch D, Garcia V, Jensen JS, Low N, Althaus CL. PeerJ. 2020 Apr 7;8:e8913.
  19. Accelerated partner therapy (APT) partner notification for people with Chlamydia trachomatis: protocol for the Limiting Undetected Sexually Transmitted infections to RedUce Morbidity (LUSTRUM) APT cross-over cluster randomised controlled trial. Estcourt CS, Howarth AR, Copas A, Low N, Mapp F, Woode Owusu M, Flowers P, Roberts T, Mercer CH, Wayal S, Symonds M, Nandwani R, Saunders J, Johnson AM, Pothoulaki M, Althaus C, Pickering K, McKinnon T, Brice S, Comer A, Tostevin A, Ogwulu CD, Vojt G, Cassell JA. BMJ Open. 2020 Mar 29;10(3):e034806.
  20. COVID-19 epidemic in Switzerland: on the importance of testing, contact tracing and isolation. Salathé M, Althaus CL, Neher R, Stringhini S, Hodcroft E, Fellay J, Zwahlen M, Senti G, Battegay M, Wilder-Smith A, Eckerle I, Egger M, Low N. Swiss Med Wkly. 2020 Mar 19;150:w20225.
  21. Gini coefficients for measuring the distribution of sexually transmitted infections among individuals with different levels of sexual activity. Gsteiger S, Low N, Sonnenberg P, Mercer CH, Althaus CL. PeerJ. 2020 Jan 20;8:e8434.
  22. Pattern of early human-to-human transmission of Wuhan 2019 novel coronavirus (2019-nCoV), December 2019 to January 2020. Riou J, Althaus CL. Euro Surveill. 2020 Jan;25(4):2000058.
  23. Transmission of and susceptibility to seasonal influenza in Switzerland from 2003 to 2015. Brugger J, Althaus CL. Epidemics. 2020 Mar;30:100373.
  24. Rise and fall of the new variant of Chlamydia trachomatis in Sweden: mathematical modelling study. Smid JH, Althaus CL, Low N, Unemo M, Herrmann B. Sex Transm Infect. 2020 Aug;96(5):375-379.
  25. Impact of age-specific immunity on the timing and burden of the next Zika virus outbreak. Counotte MJ, Althaus CL, Low N, Riou J. PLoS Negl Trop Dis. 2019 Dec 26;13(12):e0007978.
  26. Discrepancies between observed data and predictions from mathematical modelling of the impact of screening interventions on Chlamydia trachomatis prevalence. Smid J, Althaus CL, Low N. Sci Rep. 2019 May 17;9(1):7547.
  27. The use of mathematical modelling studies for evidence synthesis and guideline development: a glossary. Porgo TV, Norris SL, Salanti G, Johnson LF, Simpson JA, Low N, Egger M, Althaus CL. Res Synth Methods. 2019 Mar;10(1):125-133.
  28. Does infection with Chlamydia trachomatis induce long-lasting partial immunity? Insights from mathematical modelling. Omori R, Chemaitelly H, Althaus CL, Abu-Raddad LJ. Sex Transm Infect. 2018 Sep 4. pii: sextrans-2018-053543.
  29. Exploring variation in human papillomavirus vaccination uptake in Switzerland: a multilevel spatial analysis of a national vaccination coverage survey. Riesen M, Konstantinoudis G, Lang P, Low N, Hatz C, Maeusezahl M, Spaar A, Bühlmann M, Spycher BD, Althaus CL. BMJ Open. 2018 May 17;8(5):e021006.
  30. Age difference between heterosexual partners in Britain: implications for the spread of Chlamydia trachomatis. Smid J, Garcia V, Low N, Mercer CH, Althaus CL. Epidemics. 2018 Mar 31. pii: S1755-4365(17)30149-4.
  31. Modeling the consequences of regional heterogeneity in human papillomavirus (HPV) vaccination uptake on transmission in Switzerland. Riesen M, Garcia V, Low N, Althaus CL. Vaccine. 2017 Dec 19;35(52):7312-7321.
  32. Fitness cost and benefit of antimicrobial resistance in Neisseria gonorrhoeae: Multidisciplinary approaches are needed. Unemo M, Althaus CL. PLoS Med. 2017 Oct 31;14(10):e1002423.
  33. Developing WHO guidelines: Time to formally include evidence from mathematical modelling studies. Egger M, Johnson L, Althaus C, Schöni A, Salanti G, Low N, Norris SL. F1000Res. 2017 Aug 29;6:1584.
  34. Detection of antibiotic resistance is essential for gonorrhoea point-of-care testing: a mathematical modelling study. Fingerhuth SM, Low N, Bonhoeffer S, Althaus CL. BMC Med. 2017 Jul 26;15(1):142.
  35. A new rapid resazurin-based microdilution assay for antimicrobial susceptibility testing of Neisseria gonorrhoeae. Foerster S, Desilvestro V, Hathaway LJ, Althaus CL, Unemo M. J Antimicrob Chemother. 2017 Jul 1;72(7):1961-1968.
  36. How relevant is sexual transmission of Zika virus? Althaus CL, Low N. PLOS Med. 2016 Oct;13(10): e1002157.
  37. Modeling the Ebola epidemic: challenges and lessons for the future. Althaus CL. In Evans NG, Smith TC, Majumder MS (Eds.), Ebola’s Message: Public Health and Medicine in the Twenty-First Century. MIT Press, 2016. Post-print on BORIS
  38. Time-kill curve analysis and pharmacodynamic modelling for in vitro evaluation of antimicrobials against Neisseria gonorrhoeae. Foerster S, Unemo M, Hathaway LJ, Low N, Althaus CL. BMC Microbiol. 2016 Sep 17;16(1):216.
  39. Heterogeneity in district-level transmission of Ebola virus disease during the 2013-2015 epidemic in West Africa. Krauer F, Gsteiger S, Low N, Hansen CH, Althaus CL. PLOS Negl Trop Dis. 2016 Jul;10(7): e0004867.
  40. Antibiotic-resistant Neisseria gonorrhoeae spread faster with more treatment, not more sexual partners. Fingerhuth SM, Bonhoeffer S, Low N, Althaus CL. PLOS Pathog. 2016 May;12(5): e1005611.
  41. Potential impact of sexual transmission on Ebola virus epidemiology: Sierra Leone as a case study. Abbate JL, Murall CL, Richner H, Althaus CL. PLOS Negl Trop Dis. 2016 May;10(5): e0004676.
  42. Genetic resistance determinants, in vitro time-kill curve analysis and pharmacodynamic functions for the novel topoisomerase II inhibitor ETX0914 (AZD0914) in Neisseria gonorrhoeae. Foerster S, Golparian D, Jacobsson S, Hathaway LJ, Low N, Shafer WM, Althaus CL, Unemo M. Front Microbiol. 2015;6:1377.
  43. Rapid drop in the reproduction number during the Ebola outbreak in the Democratic Republic of Congo. Althaus CL. PeerJ. 2015 Nov 19;3:e1418.
  44. Measles vaccination coverage and cases among vaccinated persons. Althaus CL, Salathé M. Emerg Infect Dis. 2015 Aug;21(8):1480-1481.
  45. The role of superspreading in Middle East respiratory syndrome coronavirus (MERS-CoV) transmission. Kucharski AJ, Althaus CL. Euro Surveill. 2015;20(25):pii=21167(25).
  46. Ebola virus disease outbreak in Nigeria: Transmission dynamics and rapid control. Althaus CL, Low N, Musa EO, Shuaib F, Gsteiger S. Epidemics. 2015 Jun;11:80-4.
  47. Ebola superspreading. Althaus CL. Lancet Infect Dis. 2015 May;15(5):507-8.
  48. Of mice, macaques and men: scaling of virus dynamics and immune responses. Althaus CL. Front Microbiol. 2015 Apr 23;6:355.
  49. Quantifying the turnover of transcriptional subclasses of HIV-1-infected cells. Althaus CL, Joos B, Perelson AS, Günthard HF. PLOS Comput Biol. 2014 Oct;10(10): e1003871.
  50. Estimating the reproduction number of Ebola virus (EVOB) during the 2014 outbreak in West Africa. Althaus CL. PLOS Curr. 2014 Sep 2;6.
  51. Reinfection by untreated partners of people treated for Chlamydia trachomatis and Neisseria gonorrhoeae: mathematical modelling study. Low N, Heijne JC, Herzog SA, Althaus CL. Sex Transm Infect. 2014 May;90(3):254-6.
  52. Effectiveness and cost-effectiveness of traditional and new partner notification technologies for curable sexually transmitted infections: observational study, systematic reviews and mathematical modelling. Althaus CL, Turner KM, Mercer CH, Auguste P, Roberts TE, Bell G, Herzog SA, Cassell JA, Edmunds WJ, White PJ, Ward H, Low N. Health Technol Assess. 2014 Jan;18(2):1-100.
  53. Direct and indirect effects of screening for Chlamydia trachomatis on the prevention of pelvic inflammatory disease: mathematical modeling study. Herzog SA, Heijne JC, Scott P, Althaus CL, Low N. Epidemiology. 2013 Nov;24(6):854-62.
  54. Case and partnership reproduction numbers for a curable sexually transmitted infection. Heijne JC, Herzog SA, Althaus CL, Low N, Kretzschmar M. J Theor Biol. 2013 Apr 19;331C:38-47.
  55. Insights into the timing of repeated testing after treatment for Chlamydia trachomatis: data and modelling study. Heijne JC, Herzog SA, Althaus CL, Tao G, Kent C, Low N. Sex Transm Infect. 2013 Feb;89(1):57-62.
  56. Individual and population level effects of partner notification for Chlamydia trachomatis. Althaus CL, Heijne JC, Herzog SA, Roellin A, Low N. PLoS One. 2012;7(12):e51438.
  57. Timing of progression from Chlamydia trachomatis infection to pelvic inflammatory disease: a mathematical modelling study. Herzog SA, Althaus CL, Heijne JC, Oakeshott P, Kerry S, Hay P, Low N. BMC Infect Dis. 2012 Aug 11;12(1):187.
  58. Describing the Progression From Chlamydia trachomatis and Neisseria gonorrhoeae to Pelvic Inflammatory Disease: Systematic Review of Mathematical Modeling Studies. Herzog SA, Heijne JC, Althaus CL, Low N. Sex Transm Dis. 2012 Aug;39(8):628-37.
  59. Towards more robust estimates of the transmissibility of Chlamydia trachomatis. Althaus CL, Heijne JC, Low N. Sex Transm Dis. 2012 May;39(5):402-4.
  60. Impaired immune evasion in HIV through intracellular delays and multiple infection of cells. Althaus CL, De Boer RJ. Proc Biol Sci. 2012 Aug 7;279(1740):3003-10.
  61. Transmission of Chlamydia trachomatis through sexual partnerships: a comparison between three individual-based models and empirical data. Althaus CL, Turner KM, Schmid BV, Heijne JC, Kretzschmar M, Low N. J R Soc Interface. 2012 Jan 7;9(66):136-46.
  62. Implications of CTL-mediated killing of HIV-infected cells during the non-productive stage of infection. Althaus CL, De Boer RJ. PLoS One. 2011 Feb 7;6(2):e16468.
  63. The role of re-infection and partner notification in the efficacy of chlamydia screening programmes. Heijne JCM, Althaus CL, Herzog SA, Kretzschmar M, Low N. J Infect Dis. 2011 Feb 1;203(3):372-7.
  64. Transmission dynamics of Chlamydia trachomatis affect the impact of screening programmes. Althaus CL, Heijne JCM, Roellin A, Low N. Epidemics. 2010 Sep;2(3):123-31.
  65. Intracellular transactivation of HIV can account for the decelerating decay of virus load during drug therapy. Althaus CL, De Boer RJ. Mol Syst Biol. 2010; 6:348.
  66. Reassessing the human immunodeficiency virus type 1 life cycle through age-structured modeling: life span of infected cells, viral generation time, and basic reproductive number, R0. Althaus CL, De Vos AS, De Boer RJ. J Virol. 2009 Aug;83(15):7659-67.
  67. Dynamics of immune escape during HIV/SIV infection. Althaus CL, De Boer RJ. PLoS Comput Biol. 2008 Jul 18;4(7):e1000103.
  68. Dynamics of CD8+ T cell responses during acute and chronic lymphocytic choriomeningitis virus infection. Althaus CL, Ganusov VV, De Boer RJ. J Immunol. 2007 Sep 1;179(5):2944-51.
  69. Stochastic or deterministic: what is the effective population size of HIV? Kouyos RD, Althaus CL, Bonhoeffer S. Trends Microbiol. 2006 Dec;14(12):507-11.
  70. Stochastic interplay between mutation and recombination during the acquisition of drug resistance mutations in human immunodeficiency virus type 1. Althaus CL, Bonhoeffer S. J Virol. 2005 Nov;79(21):13572-8.
  71. Recombination in HIV and the evolution of drug resistance: for better or for worse? Bretscher MT, Althaus CL, Müller V, Bonhoeffer S. Bioessays. 2004 Feb; 26(2): 180-8.



  • Der Corona-Talk: Zehn Gespräche mit Christian Althaus über die neuste Entwicklung der Pandemie (NZZ am Sonntag, 2020)