New Respiratory Viruses and the Elderly

Jartti, Laura; Langen, Henriikka; Söderlund-Venermo, Maria; Vuorinen, Tytti; Ruuskanen, Olli; Jartti, Tuomas

In addition to coronaviruses 229E and OC43, the new coronaviruses NL63 and HKU1 were identified in samples of patients with respiratory symptoms in 2005-2006 [18, 21, 22, 44, 51, 52] . Like other coronaviruses, NL63 and HKU1 can be detected in a small percentage of individuals of all ages [53] . These viruses have primarily been associated with mild upper respiratory tract infections, but severe lower respiratory tract infections have also been reported [51, 52] . Diarrhea and abdominal pain may also occur, but symptoms and signs relate primarily to the respiratory tract [53] [54] [55] [56] . Chronic underlying conditions and advanced age increase the susceptibility and disease severity of CoV infections, and mortality occurs [44, 53] . In a study of community-acquired pneumonia, most of the HKU1-positive patients were old (median age 72 years) and had significant underlying diseases, especially of the respiratory and cardiovascular systems [18] . One study reported an outbreak of acute respiratory infection in a personal-care home, where CoV NL63 was identified in 7 of 8 patients aged >50 years [57] . One elderly patient died 5 days after the onset of HCoV-NL63 infection. CoV-NL63 and CoV-HKU1 are distributed throughout the globe and throughout the year, although they usually peak in the winter time [54] and cause irregular epidemics every 2-3 years [58] . Since these viruses are difficult to culture, diagnostic tests other than PCR are not available. There is neither specific antiviral therapy nor vaccine available for HCoV infections [59] .