Daily diethylcarbamazine for the treatment of Brugia malayi microfilaria carriers.

BACKGROUND. Diethylcarbamazine is effective for the treatment of brugian filaria carriers. However, the 12-day course with a daily dose of 6 mg per kg body weight is rarely completed. The World Health Organization has indicated the need for better regimes to control filariasis. METHODS. We evaluated the long term effects of three different dosage regimes of diethylcarbamazine--6, 9 and 12 mg per kg body weight--to a total of 72 mg on 93 microfilaria carriers of Brugia malayi. RESULTS. All cases treated with the 6 mg daily dose showed complete clearance of microfilaria immediately after the treatment. However, at the 9 and 12 mg daily doses only 91% and 85% of cases respectively showed complete clearance. There was a close association between the daily dose and the proportion of cases developing side-effects. The mean initial microfilaria counts were significantly higher in those who had side-effects than in those who did not. An 11-month follow up showed that with the 6 mg daily dose the recurrence rate of microfilaraemia was 29% while with the 12 mg daily dose it was 67%. Four per cent of patients on a daily dose of 6 and 9 mg discontinued treatment while 21% of those on the 12 mg daily dose did so. CONCLUSION. The 6 mg daily dose of diethylcarbamazine was the most effective and best accepted regime.

Comparison of effects of mass annual and biannual single dose therapy with diethylcarbamazine for the control of Malayan filariasis.

Annual and biannual mass single dose diethylcarbamazine citrate (DEC) at 6 mg/kg body weight was administered to people in a Brugia malayi endemic area in Shertallai part of Kerala, India, in 1987 and 1988. The coverage of population ranged between 41.33% and 66.01% in different rounds. The highest percentage of treated population developing side reactions was 8.4%. Both annual and biannual regimens were effective in reducing the microfilaria prevalence significantly from 4.90% to 1.23% and from 6.27% to 0.62% respectively and the incidence of infection was minimal in the adult population and zero among children. There was significant reduction in mean microfilaria count in both annual (81.08%) and biannual (98.00%) areas. Marked reduction in the proportion of high density carriers and infectivity index of the population after DEC therapy was also observed. Beneficial effect of mass single dose DEC on clinical cases of filariasis was evident from the reduction in the prevalence of acute manifestations, recent edema cases and the proportion of chronic cases with acute episodes. Results obtained from mass treatment areas were compared with those of the control area.

Clinical manifestations in malayan filariasis infection with special reference to lymphoedema grading.

In a door-to-door survey in Shertallai area of Kerala state in southern India, 7,766 persons were examined for clinical manifestations of filariasis. The prevalence of disease was 9.85 per cent and chronic persistent oedema (grade-II) was the predominant clinical presentation in both sexes. There was no significant difference in the age prevalence of disease between the sexes. Incidence of episodic filarial fever was higher (4.73/1000) compared to other manifestations (2.49/1000) in children aged 5-15 yr and hence this may be an useful indicator of the degree of occurrence of fresh cases of clinical filariasis. Classification of patients with lymphoedema into three grades showed that 1.65 per cent of those examined had developed lymphoedema within 6 months. Persistence of oedema (grade II) for prolonged period (13.64 +/- 1.17 yr) without skin changes indicated that the development of elephantiasis is a slow process. The clinical picture of malayan filariasis is similar to that reported elsewhere in the world except for the rarity of abscess formation is inguinal area.