Epidemiology of dengue virus infections in Nepal, 2006–2019

Abstract

Background Dengue is one of the newest emerging diseases in Nepal with increasing burden and geographic spread over the years. The main objective of this study was to explore the epidemiological patterns of dengue since its first outbreak (2006) to 2019 in Nepal. Methods This study is a retrospective analysis that covers the last 14 years (2006–2019) of reported dengue cases from Epidemiology Diseases Control Division (EDCD), Ministry of Health and Population, Government of Nepal. Reported cases were plotted over time and maps of reported case incidence were generated (from 2016 through 2019). An ecological analysis of environmental predictors of case incidence was conducted using negative binomial regression. Results While endemic dengue has been reported in Nepal since 2006, the case load has increased over time and in 2019 a total of 17 992 dengue cases were reported from 68 districts (from all seven provinces). Compared to the case incidence in 2016, incidence was approximately five times higher in 2018 [incidence rate ratio (IRR): 4.8; 95% confidence interval (CI) 1.5–15.3] and over 140 times higher in 2019 (IRR: 141.6; 95% CI 45.8–438.4). A one standard deviation increase in elevation was associated with a 90% decrease in reported case incidence (IRR: 0.10; 95% CI 0.01–0.20). However, the association between elevation and reported cases varied across the years. In 2018 there was a cluster of cases reported from high elevation Kaski District of Gandaki Province. Our results suggest that dengue infections are increasing in magnitude and expanding out of the lowland areas to higher elevations over time. Conclusions There is a high risk of dengue outbreak in the lowland Terai region, with increasing spread towards the mid-mountains and beyond as seen over the last 14 years. Urgent measures are required to increase the availability of diagnostics and resources to mitigate future dengue epidemics.

Seropositivity among Blood Samples Drawn from Suspected Dengue Cases at a Tertiary Care Centre of Nepal: A Descriptive Cross-sectional Study

“…). 8 A similar finding was reported in a study carried out in Western Uttar Pradesh, India, which revealed that 23% patients were found seropositive either by NS1 Ag or IgM Ab ELISA. 9 In the present study, among dengue positive patients, 71 (57.3%) were male and 53 (42.7%) were female with mean age of 41 year ranging from five to 83 years.…”

Aedes albopictus abundance and phenology along an altitudinal gradient in Lazio region (central Italy)

“…However, it is presumed that outbreaks at high altitudes will be characterised by reduced incidence and a shorter time span due to a lower mosquito survival rate and longer extrinsic incubation period, which are factors that negatively affect vectorial capacity [ 69 ]. Nevertheless, as indicated by previous studies, the altitudinal range of some Aedes -borne arboviruses has extended with the spread of vectors due to climate change [ 70 ]. This is also a possibility that cannot be ruled out for central Italy, where high summer temperatures have been recorded even at elevated altitudes: for instance, the maximum recorded temperatures (August 2021) in one of our highest sampling localities (Capranica Prenestina ~ 900 m asl) remained above 30 °C for a week (weather data from the archive of https://www.3bmeteo.com/ ).…”

Seroprevalence and Clinical Features of Scrub Typhus among Febrile Patients Attending a Referral Hospital in Kathmandu, Nepal

“…Nepal has a diverse topography that includes Terai, hills, and mountains. Febrile illnesses including malaria, dengue, brucellosis, scrub typhus, and leptospirosis are more common in Terai regions with spreading towards the hilly regions [23,24]. The global decline of malaria revealed an array of acute undifferentiated febrile illnesses (UFI) which has taken a high toll on human health [25].…”