key: cord-0907289-kg84j802 authors: Dao, Thi Loi; Hoang, Van Thuan; Anh Ly, Tran Duc; Goumballa, Ndiaw; Courjon, Johan; Memish, Ziad; Sokhna, Cheikh; Raoult, Didier; Parola, Philippe; Gautret, Philippe title: Epidemiology of human common coronavirus acquisition in pilgrims date: 2020-08-14 journal: Travel Medicine and Infectious Disease DOI: 10.1016/j.tmaid.2020.101845 sha: 6afa7b370abd540ee37adf40fbc9eb8e0076733c doc_id: 907289 cord_uid: kg84j802 nan Human coronaviruses (HCoVs) belong to a group of viruses that primarily cause respiratory illnesses ranging from the common cold to more severe diseases such as bronchitis, pneumonia, and respiratory distress [1] . Currently, seven different HCoV species are known to infect humans. These include HCoV-229E, HCoV-OC43, Severe Acute Respiratory Syndrome CoV (SARS-CoV), HCoV-NL63, HCoV-HKU1, Middle East Respiratory Syndrome (MERS-CoV) [1] and SARS-CoV-2, which was recently identified in humans and is responsible for an ongoing widespread epidemic affecting many countries [2] . HCoV-229E, HCoV-OC43, HCoV-NL63 and HCoV-HKU1 are the most common four HCoVs, with a global geographical distribution and a seasonal endemic transmission pattern [1] . We revisited our data by investigating the prevalence of common HCoVs in the Hajj and Grand Magal pilgrims and studying the potential risk factors for HCoV acquisition in a large number of individuals. At total of 1723 pilgrims were include. The M/F gender ratio was 1.1 and the median age was 50.6 years (ranging from 0 to 96 years). A female predominance was observed in French Hajj pilgrims, while international Hajj pilgrims were more likely to be males (Supplementary Table 1 ). Senegalese Grand Magal pilgrims were characterised by their younger age, while Hajj pilgrims were mostly middle aged or elderly individuals (Supplementary Table 1 ). In total, 70.9% of the pilgrims presented at least one respiratory symptom during travel. A cough (62.0%) and a rhinitis (48.7%) were the most frequent symptoms, followed by fever (22.4%) and dyspnoea (10.8%) ( Table 1) . Symptoms were more frequent in Hajj pilgrims as compared to Grand Magal pilgrims (Supplementary Table 1) . Overall, a total of 3388 specimens, including 1699 nasopharyngeal pre-travel specimens and 1689 post-travel specimens were investigated. In total, 244/3388 (7.2%) samples tested positive for coronaviruses including 164 (4.8%) for HCoV-229E, 34 (1.0%) for HCoV-NL63, 38 (1.1%) for HCoV-OC43 and 18 (0.5%) for HCoV-HKU1. The prevalence of HCoVs in international Hajj pilgrims sampled upon arrival in KSA, and thus reflecting the prevalence in origin countries, was 1.7% (12/692). That of French pilgrims sampled before travelling to KSA was 0.6% (4/703) and that of Senegalese pilgrims sampled before travelling to Touba was 1.0% (Hajj pilgrims) [3] . We also found a 7.7% prevalence of HCoVs acquired in asymptomatic individuals, in line with a 2.4% prevalence reported in a US study conducted in asymptomatic adults [4] . Hajj pilgrims were more likely to acquire HCoV 229E, while Grand Magal pilgrims were more likely to acquire HCoVs NL63 and OC43 (Supplementary figure 1) . In univariate analysis, acquisition of HCoVs was higher in Hajj pilgrims than in Grand Magal pilgrims. Our study also revealed annual differences in the prevalence of HCoVs that peaked in 2013 and 2016. These associations remained significant in multivariate analysis. Factors associated with annual variation in HCoV prevalence are currently unclear. Such annual variations were also observed in a study conducted in the US [5] . In addition, HCoVs acquisition was more frequent in pilgrims reporting respiratory symptoms, although this was not significant in univariate analysis. Clinical data were available for 1031/1723 (59.8%) of participants included in this work which unfortunately precluded multivariate analysis. Future studies are needed to understand the clinical significance of common HCoVs acquisition in these populations. This report reveals the role of participation in a large gathering in common HCoVs acquisition and related infections. Significant acquisition of HCoVs following participation in the Hajj pilgrimage has been reported by several authors due to overcrowded conditions encouraging the person-to-person spread of respiratory viruses including HCoVs [3] . This is of particular concern in the current context of the SARS-CoV-2 pandemic where international travel including mass gatherings played a key role in the global spread of the disease [6] . J o u r n a l P r e -p r o o f Genetic Recombination, and Pathogenesis of Coronaviruses Hajj-associated viral respiratory infections: A systematic review Asymptomatic Shedding of Respiratory Virus among an Ambulatory Population across Seasons. mSphere Human coronavirus circulation in the United States COVID-19 -the role of mass gatherings