Economic Burden of West Nile Virus Disease

Quebec, Canada, 2012-2013

Najwa Ouhoummane; Eric Tchouaket; Anne-Marie Lowe; Ann Fortin; Dahlia Kairy; Anne Vibien; Jessica Kovitz-Lensch; Terry-Nan Tannenbaum; François Milord


Emerging Infectious Diseases. 2019;25(10):1943-1950. 

In This Article

Abstract and Introduction


The economic burden of West Nile virus (WNV) infection is not known for Canada. We sought to describe the direct and indirect costs of WNV infection in the province of Quebec, Canada, up to 2 years after onset of signs and symptoms. We conducted a retrospective cohort study that included WNV cases reported during 2012 and 2013. For 90 persons infected with WNV, persons with encephalitis accounted for the largest proportion of total cost: a median cost of $21,332 per patient compared with $8,124 for West Nile meningitis (p = 0.0004) and $192 for West Nile fever (p<0.0001). When results were extrapolated to all reported WNV patients, the estimated total cost for 124 symptomatic cases was ≈$1.7 million for 2012 and that for 31 symptomatic cases was ≈$430,000 for 2013. Our study provides information for the government to make informed decisions regarding public health policies and infectious diseases prevention and control programs.


West Nile virus (WNV) infection is endemic to North America. More than 41,000 cases of WNV-related illnesses and 2,000 deaths were reported in the United States between the introduction of the virus in 1999 and 2015.[1] During the same period, 5,310 cases were reported in Canada.[2] In Quebec, the first cases were documented in 2002. After a quiet period (2004–2010), this province experienced an outbreak in 2012 (124 symptomatic cases); since 2013, the number of cases has remained stable (average of 30 cases/year).[3]

WNV causes an asymptomatic infection in 80% of cases, but in <1% of cases, a severe illness occurs with neurologic involvement, such as aseptic meningitis, encephalitis, or acute flaccid paralysis.[4,5] WNV infection and particularly neurologic disease have been associated with mild to severe clinical manifestations, might require hospitalization, and lead to long-term sequelae and death.[6]

To date, 3 studies in the United States have estimated the economic burden of WNV disease.[7–9] These estimates can be used in assessing the cost-effectiveness of various interventions designed to decrease WNV disease risk.[8] In the province of Quebec, Canada, a cost-effectiveness analysis was conducted during 2006.[10] However, this study was based on a hypothetical simulation of 2 scenarios (high activity of the virus versus low-activity season); therefore, the cost estimations could be speculative. Thus, in Canada, no data are available on the actual costs of WNV disease, and results from the United States cannot be extrapolated because of differences in the organization of the heathcare systems and costs, WNV disease prevention programs, mean income, and standards of living. Furthermore, exchange rate differences do not accurately reflect real differences in purchasing power.[11] The objective of this study was to estimate direct and indirect costs of WNV disease cases in the province of Quebec, Canada, up to 2 years after symptom onset.