Hantavirus infection as a risk factor for chronic kidney disease of unknown aetiology (CKDu) and its prevalence in endemic areas of Sri Lanka since 2010 according to a retrospective serological analysis
Chandika D. Gamage1, Shanika Nanayakkara2,3, Yomani D. Sarathkumara1,4, Devinda S. Muthusinghe5,6, Kenta Shimizu7, Jiro Arikawa7, Sithumini M. W. Lokupathirage5,6, Nishantha Nanayakkara8, Lishanthe Gunarathne9, Rohana Chandrajith10, Kouji H. Harada3, Akio Koizumi3,11, Kumiko Yoshimatsu5,6
Abstract
Background : Chronic kidney disease of unknown aetiology (CKDu) is a major public health problem in Sri Lanka, especially among agrarian communities. Although the cause of CKDu is still unknown, hantavirus infection has been proposed as a risk factor.
Methods : This study was performed using serological samples collected from two CKDu-endemic areas, Anuradhapura (2010) and Badulla districts (2010 and 2016), and a non-endemic area, Matale (2016) district. The presence of anti-Thailand orthohan- tavirus IgG antibodies was investigated in serum samples. Hantavirus seroprevalence and demographic data were epidemio- logically analysed.
Results : Seroprevalence was higher in CKDu patients (40.6–60.0%) and healthy individuals in CKDu-endemic areas (17.6– 25.5%) than in healthy individuals in non-endemic areas (3.0%). Statistically significant odds ratios (ORs) for hantavirus infec- tion in CKDu patients were detected in CKDu-endemic areas [ORs: 3.2 and 3.1; 95%confidence interval (CI): 1.8–5.5 and 1.8–5.2 in Anuradhapura and Badulla districts in 2010; and OR: 4.4, 95%CI: 2.3–8.5 in 2016 in Badulla district). Furthermore, the OR for hantavirus infection in Badulla district has increased in the last decade from 3.1 (95% CI: 1.8–5.3) to 4.4 (95% CI: 2.3–8.5).
Conclusion : Hantavirus infection has been prevalent in two distant CKDu-endemic areas since 2010. The observed significant association of hantavirus seropositivity with CKDu indicates a possible role of hantavirus infection in CKDu pathogenesis.
Keyword(s) : chronic kidney disease of unknown aetiology (CKDu) , hantavirus , retrospective serological analysis and Sri Lanka