RÉSUMÉ
BACKGROUND: Enumerating dog populations is essential to plan and evaluate rabies vaccination campaigns. To estimate vaccination coverage and dog population size in a Haitian commune, 15 sight-resight counts were conducted over two days following a government-sponsored vaccination campaign. METHODS: Dogs received temporary laminated collars and livestock wax marks on the head and sides at the time of rabies vaccination. After the vaccination campaign, pairs of surveyors walked pre-defined routes through targeted neighborhoods, photographing and recording characteristics and location of each dog seen on a standardized data sheet. On the second survey day, surveyors retraced the prior day's track, followed the same procedure, and indicated in addition whether they believed the dogs were resighted from the prior day. After completion of the field survey, two independent evaluators reviewed photographs and characteristics of each dog to assess which had vaccination marks and which were resighted. Surveyor and photo-reviewer sight-resight decisions were compared using Cohen's kappa, and population estimates were compared using Lincoln-Petersen 95% confidence intervals. RESULTS: Field-surveyors identified dogs consistent with the photograph evaluations in 629 out of 800 instances (78.6%, Cohen's kappa of 0.12). Despite this inconsistency, the population estimates resulting from the field and final determinations were not significantly different at 1,789 (95% CI 1,677 to 1,901) and 1,978 (95% CI 1,839 to 2,118). Vaccination coverage was also the same at 55% and 56%; however, an observed vaccination mark loss of 13.8% suggests that the true coverage may have been closer to 64%. CONCLUSION: Using photos improved dog identification during the sight-resight study, leading to a higher population estimate. Despite using a 2-mark system to temporarily identify vaccinated dogs, a significant proportion had lost all identifying marks by the second day of field surveys. Efforts to estimate vaccination coverage using sight-resight surveys should consider improvement of marking techniques or better accounting for potential loss of marks in their free-roaming dog vaccination coverage assessments.
RÉSUMÉ
Haiti has historically vaccinated between 100,000 and 300,000 dogs annually against rabies, however national authorities have not been able to reach and maintain the 70% coverage required to eliminate the canine rabies virus variant. Haiti conducts massive dog vaccination campaigns on an annual basis and utilizes both central point and door-to-door methods. These methods require that dog owners are aware of the dates and locations of the campaign. To improve this awareness among dog owners, 600,000 text messages were sent to phones in two Haitian communes (Gonaives and Saint-Marc) to remind dog owners to attend the campaign. Text messages were delivered on the second day and at the mid-point of the campaign. A post-campaign household survey was conducted to assess dog owner's perception of the text messages and the impact on their participation in the vaccination campaign. Overall, 147 of 160 (91.9%) text-receiving dog owners indicated the text was helpful, and 162 of 187 (86.6%) responding dog owners said they would like to receive text reminders during future rabies vaccination campaigns. In areas hosting one-day central point campaigns, dog owners who received the text were 2.0 (95% CI 1.1, 3.6) times more likely to have participated in the campaign (73.1% attendance among those who received the text vs 36.4% among those who did not). In areas incorporating door-to-door vaccination over multiple days there was no significant difference in participation between dog owners who did and did not receive a text. Text message reminders were well-received and significantly improved campaign attendance, indicating that short message service (SMS) alerts may be a successful strategy in low resource areas with large free roaming dog populations.