Effectiveness of Eupatorium perfoliatum 30C in prevention of Dengue Fever and Acute Febrile Illness during 2017 dengue outbreak in urban slums of Delhi - A prospective, open-label, community-based, parallel cohort study

Objective This study was undertaken to assess the effectiveness of Eupatorium perfoliatum (EP) 30C on the incidence of dengue fever and acute febrile illness (AFI) during the 2017 dengue outbreak. Methods We conducted a prospective, open-label, community-based parallel cohort study involving apparently healthy individuals residing in 06 urban slums (JJ colony) of Delhi. The participants were enrolled in two cohorts - the medicine cohort (MC) and the control cohort (CC). Participants in MC were given weekly one dose of EP 30C for 10 weeks along with Information, Education & Communication (IEC) material regarding dengue. Participants in the CC were provided with the IEC material only. The primary outcome measure was the incidence of dengue fever as per case definitions notified in the national guidelines for clinical management of dengue fever by the Government of India during the 10 weeks follow-up period. The secondary outcome measures were the incidence of AFI and the hospitalization of confirmed dengue cases. Results The analysis included 40,769 participants residing in 06 slum clusters of Delhi, out of which 28,321 participants were in MC and 12,448 participants were in CC. The incidence of laboratory-confirmed dengue in the MC was 2.57 per 10,000-person week (95% confidence interval [CI], 2.02 to 3.22) in comparison with 7.55 per 10,000-person week (95% CI, 6.12 to 9.21) in the CC. The incidence of AFI in the MC was 19.66 per 10,000-person week (95% CI, 18.07 to 21.36) in comparison with 40.96 per 10,000-person week (95% CI, 37.48 to 44.67) in the CC. The overall protective effect (PE) of EP against laboratory-confirmed dengue was 65.77% (95% CI, 53.37 to 74.87; p = 0.001), and against AFI was 52.58% (95% CI, 46.37 to 58.07; p = 0.0001). Hospitalization reported in the MC was nil as against 4.35% in the CC. No dengue-related case fatalities were reported from either cohort. None of the participants from the MC reported any adverse events owing to the prophylactic intervention. Conclusion The study concludes that Eupatorium perfoliatum 30C was able to prevent dengue significantly. Randomized controlled trials are needed to confirm or refute our findings.