Decline of brugian filariasis in Cherthala taluk, Alappuzha district, Kerala.

A total of 4492 persons from 5 panchayats and 1 town were investigated from the Brugia malayi most endemic taluk of Cherthala, Alappuzha district of Kerala state. The urban area in Cherthala taluk only revealed mf carriers; mf rate was 0.13%. Rural areas in Cherthala taluk were free from infection. Microfilaria rate had declined by 99.5% and disease rate by 90.7% in Cherthala compared to 1934 prevalence. Shedding of sheath by B. malayi microfilariae was recorded for the first time in India. The youngest person with microfilaria and disease manifestation was 4 1/2 and 9 years respectively. All the 3 major vectors, Mansonia annulifera, Ma.uniformis and Culex quinquefasciatus were prevalent throughout. Complete disappearance of brugian filariasis from this taluk is a distinct possibility. The reasons for the drastic decline are discussed.

A study on trend of relapse in leprosy and factors influencing relapse.

A retrospective analysis of data pertaining to the rural field operation area of the Central Leprosy Teaching and Research Institute, Chengalpattu, Tamil Nadu, was carried out to determine the magnitude of relapse after MDT and its significance with other variables. The study included 3248 leprosy patients who have successfully completed treatment during 1987-2003, of whom 2892 were PB and 356 MB cases. A total of 58 cases of relapse was reported which gives a crude cumulative relapse rate of 1.78% for the 16-year period of follow-up and the rates for PB and MB were 1.9% and 0.84% respectively. With respect to PB cases, 68% of relapses were reported in the first 3 years of RFT. The person-year relapse rate was highly significant with regard to the number of skin lesions (p<0.0002) and nerve involvement (p<0.0002). The person-year relapse rate did not differ significantly between PB and MB leprosy, male and female, and child and adult cases. RFT year cohort relapse rate reveals that the introduction of MB-MDT regimen for PB leprosy had resulted in the reduction of relapses among PB cases after 1998. The relapse rate with reference to the time gap after RFT reveals that relapse declines with passage of time after RFT. The risk of relapse was very low in both PB and MB leprosy which fact emphasizes that proper counselling about signs and symptoms of relapse during RFT is adequate to combat the problem. A majority of relapses occurred in the first three years after RFT. The number of skin lesions and involvement of nerves were the main risk factors for relapse.