The Risk Factors of Seasonal Hyperacute Panuveitis

Abstract

Background: Seasonal Hyperacute Panuveitis (SHAPU) is an eye disease of unclear aetiology occurring cyclically during the autumn in odd years in Nepal causing blindness within a week. This study is the first of its type to investigate the risk factors of SHAPU. Methods: A multicentric national level case-control study was performed during the 2017 SHAPU outbreak. Cases were matched to controls in a 1:3 ratio based on age, sex and geographic area.Questionnaire-based personal interview was used and risk factors were categorized as biological and behavioral. For univariate analysis, frequency, median and interquartile range was calculated. Chi-squared test with/without continuity correction and Fisher's exact test were used. Multivariate conditional logistic regressions were used for all the independent variables for p <0.1 in the univariate analyses. Results: We identified 35 cases and 105 controls; 71.4% were children≤16 years (38-day infant to 50-year-old). All were immunocompetent individuals, males were 57.1% and females 42.9%. Potential risks such as visible moths/butterfly activity, contact with livestock, and attending mass gatherings of people were not reported more frequently in cases vs controls in univariate analyses. Differences in possibly protective factors such as self-reported mosquito net use, light off at night while sleeping, and habit of hands/face washing after physical contact/touch with any insects/ butterflies/birds were not statistically significant between both groups. In multivariate model, SHAPU cases were significantly more likely than controls to report physical contact with butterflies/white moths (Adjusted OR:6.89; CI:2.79-17.01,p < .001). Conclusions: Direct physical contact with butterflies/moths was associated with significantly increased odds of SHAPU cases.

Sporadic summer outbreak of SHAPU in even years: Does the pattern match with the usual autumn outbreak?

“… 6 , 7 However, their pattern and clinical profile has not been described till date. The white moths have been proven as the potential risk factors for SHAPU causation 8 and their population increases during autumn of odd years.…”

Challenges of Pediatric Cataract Surgery in a Case of Seasonal Hyperacute Panuveitis (SHAPU)

“…Most cases have been reported from hilly regions in and around Kaski district of Nepal. Association has been seen with direct physical exposure or vicinity to the white moths [ 1 ]. History of physical contact with moth was seen in 48.6% of SHAPU cases and 11.4% of control in a case control study [ 1 ].…”

“…Association has been seen with direct physical exposure or vicinity to the white moths [ 1 ]. History of physical contact with moth was seen in 48.6% of SHAPU cases and 11.4% of control in a case control study [ 1 ]. It causes uniocular blindness and is the commonest cause of panuveitis among the Nepalese children [ 1 – 3 ].…”

“…History of physical contact with moth was seen in 48.6% of SHAPU cases and 11.4% of control in a case control study [ 1 ]. It causes uniocular blindness and is the commonest cause of panuveitis among the Nepalese children [ 1 – 3 ]. In a previous study, 71.4% cases were children [ 1 ].…”

“…It causes uniocular blindness and is the commonest cause of panuveitis among the Nepalese children [ 1 – 3 ]. In a previous study, 71.4% cases were children [ 1 ]. The role of white moths in SHAPU causation is still unclear, and studies are being conducted to evaluate, whether the SHAPU is due to the auto-immune response to the moth toxins or due to pathogens delivered by the moths over the ocular surface.…”