226 MOSQUITO ERADICATION 



communities the direct offensive anti-mosquito campaigns that 

 are being waged in cities, towns and villages today. 



Several community protective projects have been successfully 

 carried out, however. These include both screening and quinine- 

 treatment campaigns. Some of these have extended over com- 

 paratively wide areas, and have succeeded in greatly reducing the 

 incidence of malaria. 



RURAL COMMUNITY PROTECTIVE DEMONSTRATIONS 



An interesting demonstration of the efficacy of screening as a 

 community protective measure, carried out on a group of planta- 

 tions near Lake Village, Ark., is described in the chapter on 

 screening. In this demonstration, no other measure than 

 screening was employed; yet a reduction of 70.6 per cent in the 

 incidence of malaria was obtained at an annual per capita cost of 

 only $1.76. 



In connection with this same demonstration, an investigation 

 as to the efficacy of quinine treatment was carried out on another 

 group of plantations. Of a total of 306 persons who received 

 treatment, 69 were given sterilizing doses and the remainder, 237, 

 were given immunizing doses. A parasite index taken in May, 

 1916, at the beginning of the work, and again in December of the 

 same year, showed a reduction of 64.45 per cent. The per 

 capita cost of the work, omitting overhead expenses, was 57 

 cents. The cost of malaria per capita for a control untreated 

 group was $2.52. 



In 1918, a demonstration of malaria reduction by quinine 

 treatment of plasmodia carriers was carried out in Sunflower 

 County, Mississippi. The county had a population of about 

 9,000, about 1,000 living in the town of Ruleville and the rest 

 on cotton plantations. A survey showed that, of the rural 

 population, 40 per cent had had clinical malaria within 12 

 months and that, of the remaining 60 per cent, 22 per cent had the 

 parasites in their blood. On one plantation, having a tenant 

 population of 600, the average annual physicians' bill for the 

 preceding 10 years had been approximately $4,000, of which 

 $3,000 was attributed to malaria. As a result of the work, there 

 was no transmission of malaria in Ruleville during the year, and 

 the town was free from mosquitoes. In the rural area, the reduc- 

 tion in the incidence of malaria during the year was estimated at 



