a. Public education and outreach - Based on experience elsewhere, we assigned a high priority to early, ongoing and aggressive education/outreach. This was directed at the public, medical community, local officials and legislators and focused on the nature of the threat, the compelling need for individual vigilance and prevention, and, finally, the steps the state would take to protect public health. The letter was reduced to a written protocol, which was broadly circulated.

b. Larvaciding/Source-reduction - It was very early in the process agreed that reducing mosquito populations at the larval stage should be a keystone of our response. Two high-risk breeding habitats were identified, catch basin sumps and stagnant surface impoundments, such as retention basins and roadside ditches. The state purchased quantities of the pesticide Altosid in pellet form to treat catch basins ($108,000) and Bti in briquette form to treat surface impoundments ($42,000). Cities and towns, state and federal agencies agreed to and subsequently did treat target habitats up to four times over the course of the summer (550,000 doses of Altosid, 53,000 Bti briquettes). Empirical observation was that this effort was locally effective in reducing mosquito populations.

c. Surveillance/testing: Because it was known from the New York experience that native birds, particularly crows, were highly susceptible to WNV, a considerable effort was made to identify and test suspect birds for presence of the disease. Three hundred twenty-eight (328) birds were tested over the course of the summer out of 936 retrieved and 88 of these (27%) were confirmed positive for WNV, 4 for EEE. Disease in birds was first confirmed in early August, spiked through September and October, and was seen at reduced levels as late as mid-November. Mosquito results as already noted, were uniformly negative even though testing extended from May to October 10 and involved an average of 26 CO2 baited light traps set weekly in various locations statewide.

d. Adulticiding: Based on CDC recommendations, Rhode Island's protocol called for ground spraying of the products sumethrin or resmethrin within a three mile radius of confirmed WNV bird deaths. Again, the product was purchased by the state ($79,200, although only $27,000 worth of product was applied, the rest remaining in inventory). And again, application was by cities and towns with spray equipment purchased by the state ($33,800). Fifteen municipalities were ultimately involved in 18 separate spraying efforts. A number of additional late season spraying efforts had to be cancelled due to unacceptable weather or temperature conditions and the last spraying, therefore occurred on September 20.

a. Public education and outreach: - Principally focused on personal protection and good housekeeping regarding mosquito reduction.

b. Larvaciding/source-reduction: - We will be providing municipalities appropriate pesticide formulations to treat catch basins and stagnant surface water impoundments throughout the mosquito-breeding season. The objective will be to reduce adult mosquito population levels by interdicting the breeding cycle at its most vulnerable (larval) stage.

c. Surveillance/testing: We again plan to collect and test both birds and mosquitoes for evidence of WNV. In a shift from last year, however, we anticipate transferring our trapping and testing focus from birds to mosquitoes once we see initial confirmation of the disease in birds. The reason for this shift is that there does not appear to be a particularly close correlation between evidence of disease in birds and increased human health risk. We, therefore, believe that it is a better use of our surveillance and testing capacity to focus maximum effort on mosquitoes since a good correlation does exist there.

d. Adulticiding: In a departure from last year's approach, we anticipate being much more conservative in authorizing ground spraying of pesticides designed to kill adult (flying) mosquitoes. Because of the previously referenced poor correlation between WNV in birds and risk to humans observed over last summer, we intend to authorize spraying only upon observing evidence of disease in mosquito species that are known human biters. Even there, we are weighing the wisdom of responding to single disease isolations in mosquitoes and may require further confirmatory testing before authorizing spraying.