Since January 2020, Elsevier has established a COVID-19 resource center on its public news and information website, Elsevier Connect, providing free information in English and Mandarin on the novel coronavirus. The company has granted permission to make all its COVID-19-related research available in PubMed Central and other publicly funded repositories, allowing unrestricted research reuse and analyses with acknowledgment of the original source. This permission is granted for as long as the COVID-19 resource center remains active. The article "Hosts and Sources of Endemic Human Coronaviruses" by Victor M. Corman, Doreen Muth, Daniela Niemeyer, Christian Drosten, and colleagues from Charité–Universitätsmedizin Berlin and the German Center for Infection Research discusses the natural hosts and zoonotic sources of four endemic human coronaviruses (HCoVs): HCoV-229E, HCoV-NL63, HCoV-OC43, and HCoV-HKU1. These viruses contribute significantly to respiratory tract infections in both adults and children. While their clinical manifestations resemble those of the common cold, their evolutionary histories and host associations provide insights into past human pandemics. The authors suggest that HCoV-NL63 and HCoV-229E may originate from bat reservoirs, while HCoV-OC43 and HCoV-HKU1 likely speciated from rodent-associated viruses. HCoV-OC43 is thought to have emerged from ancestors in domestic animals, such as cattle or swine, and HCoV-229E may have been transferred from dromedary camels, similar to the transmission of MERS-CoV. The article also highlights the importance of understanding the natural history of these viruses to recognize early signs of emergence from highly exposed hosts like livestock species.Since January 2020, Elsevier has established a COVID-19 resource center on its public news and information website, Elsevier Connect, providing free information in English and Mandarin on the novel coronavirus. The company has granted permission to make all its COVID-19-related research available in PubMed Central and other publicly funded repositories, allowing unrestricted research reuse and analyses with acknowledgment of the original source. This permission is granted for as long as the COVID-19 resource center remains active. The article "Hosts and Sources of Endemic Human Coronaviruses" by Victor M. Corman, Doreen Muth, Daniela Niemeyer, Christian Drosten, and colleagues from Charité–Universitätsmedizin Berlin and the German Center for Infection Research discusses the natural hosts and zoonotic sources of four endemic human coronaviruses (HCoVs): HCoV-229E, HCoV-NL63, HCoV-OC43, and HCoV-HKU1. These viruses contribute significantly to respiratory tract infections in both adults and children. While their clinical manifestations resemble those of the common cold, their evolutionary histories and host associations provide insights into past human pandemics. The authors suggest that HCoV-NL63 and HCoV-229E may originate from bat reservoirs, while HCoV-OC43 and HCoV-HKU1 likely speciated from rodent-associated viruses. HCoV-OC43 is thought to have emerged from ancestors in domestic animals, such as cattle or swine, and HCoV-229E may have been transferred from dromedary camels, similar to the transmission of MERS-CoV. The article also highlights the importance of understanding the natural history of these viruses to recognize early signs of emergence from highly exposed hosts like livestock species.