Higher airborne pollen concentrations correlated with increased SARS-CoV-2 infection rates, as evidenced from 31 countries across the globe
Authors: Damialis Athanasios , Gilles Stefanie , Sofiev Mikhail , Sofieva Viktoria , Kolek Franziska , Bayr Daniela , Plaza Maria P. , Leier-Wirtz Vivien , Kaschuba Sigrid , Ziska Lewis H. , Bielory Leonard , Makra László , del Mar Trigo Maria ,   COVID-19/POLLEN study group, Traidl-Hoffmann Claudia , Oliver Gilles , Pham-Thi Nhan , Thibaudon M. , Arino Arturo H. , Belmonte J. , Morales Patricia Cervigon , de Linares Concepcion , Fernández Delia , Fernandez-Rodriguez Santiago , Arguisuelas Antonia Gabaldon , Galan Carmen , González-Alonso Monica , Lara Beatriz , Grau José María Moreno , Oteros José , Pérez-Badia Rosa , Pérez-de-Zabalza Anabel , Picornell Antonio , Recio Marta , Robles Estrella , Rodríguez-Fernández Alberto , Rodríguez-Rajo Javier F. , Rojo Jesús , Valenzuela Luis Ruiz , Bergmann Karl-Christian , Werchan Barbora , Werchan Matthias , Buters Jeroen T.M. , Bastl Maximilian , Dunker Susanne , Hornick Thomas , Roldán Nestor González , Gilge Stefan , Clot B. , Finemann Stanley , Ford Linda B. , Gomez Robert Anthony , Kamboj Sanjay , Wilhelm Wayne , Beggs Paul J. , Burton Pamela , Davies Janet M , Haberle Simon , Katelaris Constance Helen , Keaney Ben , Milic Andelija , Miller Victoria , van Haeften Shanice , Bonini Maira , Bordin Anna , Ceriotti Valentina , Cristofolini Fabiana , Cristofori Antonella , Gottardini Elena , Marcer Guido , Marraccini Paolo , Mascagni Paolo , Meriggi Antonio , Pace Loretta , Pini Alberto , Tacca Maria Cristina , Bruffaerts Nicolas , Hoebeke Lucie , Adams-Groom Beverley , Pashley Catherine Helen , Satchwell Jack , Skjøth C. A. , Symon Fiona A. , Miguel Antunes Celia Maria , Caeiro Elsa , Camacho Irene Gomes Câmara , Rodrigues Costa Ana Cristina , Deus Ricardo João Ratola Capela , Ferreira Manuel Branco , Lopes Fonseca Joao Almeida , Galveias Jorge Ana Catarina , Ribeiro Helena , Tavares Beatriz , Grewling Łukasz , Grinn-Gofroń Agnieszka , Jurkiewicz Dariusz , Kalinowska Ewa , Lipiec Agnieszka A , Myszkowska Dorota , Piotrowska-Weryszko Krystyna , Puc Malgorzata , Rapiejko Anna Agnieszka , Rapiejko Piotr , Weryszko-Chmielewska Elżbieta , Ziemianin Monika , Berman Dilys , Hoek Werner , Manjra Ahmed Ismail , Peter Jonathan , Dahl Å. , Ekebom Agneta , Stjepanovic Barbara , Večenaj Ana , Celenk S. , Goksel Ozlem , Goksel Tuncay , Guvensen Aykut , Pinar Nur Munevver , Sackesen Cansin , Sahin Aydar Acar , Uguz Ulas , Yazici Duygu , Kajitor-Apatini Dóra , Magyar Donát , Szigeti Tamás , Sikoparija Branko , Seliger Andreja Kofol , Simčič Anja , Oh Jae-Won , Charalampopoulos Athanasios , Vokou D. , Rasmussen K. , Barrionuevo Laura Beatriz , Ramon German Dario , de Weger Letty A. , Koenders Mieke M.J.F. , van Vliet Arnold J.H. , Dušička Jozef , Lafférsová Janka , Ščevková Jana , Rybníček O. , Coates Frances , Jurgens Dawn , Šaulienė Ingrida , Severova Elena , Rodinkova V. , Bortnyk Mykyta , Palamarchuk Olena , Yasniuk Maryna , Louna-Korteniemi Maria , Pätsi Sanna , Saarto Annika , Toiviainen Linnea , Sozinova Olga , Jia Peng 
Published: March 2021

Significance
Coexposure to airborne pollen enhances susceptibility to respiratory viral infections, regardless of the allergy status. We hypothesized this could be also true for SARS-CoV-2 infections. To investigate this, we tested for relationships between SARS-CoV-2 infection rates and pollen concentrations, along with humidity, temperature, population density, and lockdown effects. Our unique dataset derives from 130 sites in 31 countries and across five continents. We found that pollen, sometimes in synergy with humidity and temperature, explained, on average, 44% of the infection rate variability. Lockdown halved infection rates under similar pollen concentrations. As we cannot completely avoid pollen exposure, we suggest wide dissemination of pollen−virus coexposure information to encourage high-risk individuals to wear particle filter masks during high springtime pollen concentrations.