[Follow-up survey on the long-term effects of DEC medicated salt in the control of filariasis bancrofti (author's transl)]. Mass treatment of filariasis using DEC-medicated salt. Efficacy of mass single-dose diethylcarbamazine and DEC-fortified salt against bancroftian filariasis in Papua New Guinea six months after treatment. The effect of salt medicated with diethylcarbamazine in bancroftian filariasis. A community-based trial for the control of lymphatic filariasis and iodine deficiency using salt fortified with diethylcarbamazine and iodine. Efficacy of diethylcarbamazine-medicated salt for microfilaraemia of Brugia malayi. Efficacy of diethylcarbamazine medicated salt in interrupting Brugia malayi transmission in hill tribe settlements in Kerala State. Control of Bancroftian filariasis by cooking salt medicated with diethylcarbamazine. Efficacy of 28-day and 40-day regimens of sodium stibogluconate (Pentostam) in the treatment of mucosal leishmaniasis.
nan Diethylcarbamazine (DEC)-medicated salt was used to control bancroftian filariasis in 20 endemic counties and cities of Fujian Province in China. The population was 5,189,126 and the microfilaria (mf) rates were between 1.56 and 11.81%. The total dose of DEC was 6-10.5 g per person over a period of 2-4 months. Six to 9 months after treatment the mf rate was reduced to 0-0.57% with a mean of 0.07% (621/823,796). In 184 villages sampled one year post treatment the mf rate was 0.22% (371/171,067) and in 29 villages 2-4 years after treatment the mf rate was 0.05% (31/56,459). In a region of endemic Malayan filariasis, with a population of 67,778 and mf rate of 3.82-4.36%, treatment with DEC-medicated salt to a dosage of 3.2 g DEC per person was administered for 2 months. Six months after treatment the mean mf rate was reduced from 4.08 to 0.26% (10/3841). Filariasis in all the villages controlled with DEC-medicated salt reached the basic criteria of elimination (mf rate below 1%). The efficacy of two diethylcarbamazine (DEC) treatment strategies to control bancroftian filariasis, diethylcarbamazine-fortified salt (DEC-FS) and a single DEC dose on mass administration, was evaluated in two communities in Papua New Guinea with pretreatment antigen prevalence of 55% and 71%. In the first community 0.2% w/w diethylcarbamazine-fortified salt was distributed monthly to accepting households at no cost for 12 months. In the second community a single DEC dose based on body size but designed to give about 6 mg/kg was administered to eligible acceptors. Despite wide variation in antigen prevalence among study villages there were marked reductions in prevalences under both treatment strategies. Among individuals antigenaemic on day 0, DEC-FS and a single DEC dose gave filaria antigen clearance rates of 43% and 13%, respectively. In the salt-treated community the incidence of antigenaemia after 6 months in acceptors from households that received 5 kg or more of DEC-FS was 14% whereas in those receiving less than 5 kg salt was 4%. The incidence rates in the second community in those that received < 2.5 and > or = 2.5 tablets were 16% and 8%, respectively. The two treatment strategies were simple to manage and appropriate for developing countries and were widely accepted. DEC-FS was more efficacious than single-dose DEC tablets but a single administration of DEC tablets is easier to administer. The paper describes a trial conducted in Tanzania of the effect on bancroftian microfilaraemia of common salt medicated with diethylcarbamazine at a 0.1% (w/w) concentration, when given to a closed population of 600-700 with a known salt intake.After good observer agreement in microfilarial counting had been demonstrated, quantitative blood surveys were performed monthly on known carriers. Paired pretreatment microfilarial counts from the same patients at an interval of 4 months suggested a natural fluctuation in microfilarial densities and emphasized the need for parallel concurrent controls during treatment.During the trial the mean microfilarial densities fell steadily, being reduced by 73% at 3 months and 90% after 6 months. Tolerance to the drug-salt mixture was extremely good.Problems of planning, salt preparation and assessment of results are discussed and the importance of correct experimental design in future trials is stressed. The authors suggest that a trial of salt containing 0.2% (w/w) diethylcarbamazine may achieve optimum results. They point out that, while the use of diethylcarbamazine-medicated salt may prove useful in reducing transmission in closed communities or in endemic areas with no alternative source of salt, its extension to national populations as a sole means of bancroftian filariasis control would be of problematical value. To evaluate the effectiveness of salt fortified with diethylcarbamazine (DEC) and iodine for elimination of Bancroftian filariasis and iodine deficiency, all consenting residents of Miton, Haiti (n = 1,932) were given salt fortified with 0.25% diethylcarbamazine and 25 ppm of iodine for one year. Wuchereria bancrofti microfilaria prevalence and intensity, antigenemia, and urinary iodine were measured before and one year after salt distribution began. To measure the effect of DEC-fortified salt on adult worm motility, 15 microfilaria-positive men were examined by ultrasound of the scrotal area. Entomologic surveys were conducted to determine the proportion of W. bancrofti-infected Culex quinquefasciatus. After one year of treatment, the prevalence and intensity of microfilaremia were both reduced by more than 95%, while antigenemia levels were reduced by 60%. The motility of adult worms, as detected by ultrasound, was decreased, but not significantly, by DEC-fortified salt. The proportion of vector mosquitoes carrying infective stage larvae decreased significantly from 2.3% in the nine months before the intervention to 0.2% in the last three-month follow-up period. Iodine deficiency, which had been moderate to severe, was eliminated after one year of iodized salt consumption. The DEC-fortified salt was well accepted by the community and reduced microfilaremia and transmission to low levels in the absence of reported side effects. Based on these results, salt cofortified with DEC and iodine should be considered as a concurrent intervention for lymphatic filariasis and iodine deficiency elimination programs. Pilot studies in India and abroad have demonstrated the benefit of cooking salt fortified with diethylcarbamazine citrate (DEC) for the control of lymphatic filariasis. In India, DEC-medicated salt has been introduced on a commercial basis in the Cherthala region of Kerala, which is endemic for Brugia malayi (B. malayi). We studied the efficacy of DEC-medicated salt in the clearance of microfilaraemia of B. malayi.
                Eighteen cases of microfilaraemia (11 men; 7 women) were selected; 14 in the experimental group (i.e. treated with 0.2% w/w DEC-medicated salt) and the rest as the control group who were given a placebo. The consumption of salt and the status of parasitaemia were monitored till all the microfilaria carriers became negative.
                There was a significant reduction in the density of microfilariae (intensity) among the treated individuals over a period of time. The duration required for the clearance of microfilariae ranged from 9 to 30 [mean (SD) 19.4 (1.7)] weeks. All microfilaraemics except one reported side-effects which were mild-to-moderate and persisted for a maximum period of one month.
                DEC-medicated salt effectively clears microfilariae within 30 weeks in parasitaemic individuals. No 'endemic normals' reported any side-effects, though these were common among the microfilaria carriers. A filariasis survey carried out about eight years after achieving zero microfilaria (mf) rates following administration of diethylcarbamazine (DEC) medicated salt in the Kani hill tribe settlements in Quilon and Thiruvananthapuram districts of Kerala State revealed that there was no reappearance of Brugia malayi infection in the experimental areas. Mf rates were maintained at zero level in the experimental villages, while in the control villages, 2.9 per cent mf positives were observed. Mansonia (Mansonioides) uniformis dissected did not reveal filarial infection. It is concluded that DEC medicated salt regime in the experimental areas of Kani hill tribe settlements has been successful in effectively interrupting B. malayi transmission. Pilot studies in other B. malayi endemic areas of India using DEC medicated salt regime with the objective of eliminating B. malayi transmission are advocated, since the parasite has a restricted distribution in India and is already showing a declining trend. In small-scale pilot trials, filarial infection can usually be reduced to low levels by oral administration of diethylcarbamazine to all the persons concerned; but in mass campaigns it is often difficult to persuade large numbers of people to swallow the tablets. In order to overcome this difficulty the authors propose that the compound be incorporated into cooking salt, as has been done with chloroquine to control malaria. There are many reasons why this method of medication should be more effective against filariasis than it has often been against malaria.Laboratory trials showed that cooking the compound in food did not make it toxic for rats or diminish its antifilarial activity. A pilot trial was carried out at Recife, Brazil, in which 1000 adults received salt containing 0.4% diethylcarbamazine (corresponding to a daily intake of 100 mg/day) for 40 days, and then salt containing 0.1% compound for a year. This medication was simple to administer; it was quite acceptable to the subjects; it caused no untoward effects; and it removed almost all the microfilariae from the blood. Administration of medicated salt (0.3%) for 18 days to another group of 1300 adults was well tolerated and produced a considerable reduction of the microfilarial load; but this short period was insufficient to remove all the microfilariae.The authors recommend that this method of administering diethylcarbamazine to large numbers of people should be investigated further to see if it could be used for mass campaigns to control filariasis. The efficacy and toxicity of two regimens of antimony, 28 and 40 days of 20 mg of antimony/kg/day, were compared in the treatment of culture-positive mucosal leishmaniasis involving more than one anatomic site. Forty consecutive eligible Peruvians with infiltrative or ulcerative mucosal disease of the lips, nose, palate-uvula-pharynx, or larynx-epiglottis were randomized to receive either 28 days (P28) or 40 days (P40) of sodium stibogluconate (Pentostam). Treatment was prematurely terminated due to thrombocytopenia in three patients and two patients did not complete six months of follow-up. At one month post-treatment, 13% (2 of 16) of the P28 patients and 16% (3 of 19) of the P40 patients no longer had infiltrates or ulcers and were initially considered cured. During a further 11 months of follow-up, infiltrated lesions healed in eight more P28 patients and in 10 more P40 patients. The cure rate after 12 months of follow-up was therefore 63% for both groups (10 of 16 in the P28 group and 12 of 19 in the P40 group). The total of 13 patients who had infiltrates or ulcers at the 9-12-month follow-up were considered failures. All seven patients (three in the P28 group and four in the P40 group) whose lesions were culture-positive for Leishmania at some point in the 12 months after treatment, and who were thereby parasitologic failures, were also clinical failures.(ABSTRACT TRUNCATED AT 250 WORDS)
DEC-medicated salt is an effective intervention when maintained with levels of coverage of at least 90% for at least six months. Further studies are required to assess the effects of continuous low-dose, DEC-medicated salt on adult worms, disease prevalence, and development of drug resistance.