Epidemiology of human geohelminth infections (ascariasis, trichuriasis and necatoriasis) in Lushui and Puer Counties, Yunnan Province, China.

Between April and June of 1998, the prevalence and intensity of geohelminth infections caused by hookworm, Ascaris and Trichuris were investigated in two rural Yunnan villages. In Liuku, a village of Lisu indigenous people in Lushui County, there was an overall geohelminth prevalence of 72% (48%, 43% and 16% for hookworm infection, ascariasis, and trichuriasis, respectively). The prevalence of ascariasis was greatest among preschool and school aged children, whereas the prevalence of trichuriasis was greatest among teenagers and the prevalence of hookworm increased until the age of 10-15 and then remained high throughout adulthood. In Linger, a village of Han Chinese, located in Puer County, there was an overall geohelminth prevalence of 77% (30%, 60% and 36% for hookworm infection, ascariasis, and trichuriasis, respectively). The differences in prevalence for hookworm and ascariasis were statistically significant. The prevalence of hookworm in Linger increased steadily with age and did not plateau, but there were no discernible patterns of prevalence versus age for either ascariasis or trichuriasis. Heavy trichuriasis infections were noted to occur in Linger. In both villages, more than 98% of the hookworm infections were of light and moderate intensity. Both by morphologic identification of third-stage infective larvae (L3) from eggs as well as identification of adult hookworms recovered from adult residents after treatment with quantrel, Necator americanus was identified as the exclusive hookworm in each village. Geohelminth infections caused by Ascaris, Trichuris and hookworm remain highly endemic to the rural areas of Yunnan Province in southwestern China.

Minimum effective doses of mebendazole in treatment of soil-transmitted helminths.

Three hundred and fifteen primary school children infected with soil-transmitted helminths were divided into 5 groups. Three groups were treated with 25, 50 and 75 mg mebendazole (MBZ) single dose. One group was given MBZ conventional dose of 100 mg twice daily for 3 days and another group was given albendazole (ABZ) standard dose of 400 mg single dose. Every trial lower MBZ dose 75 mg, 50 mg and 25 mg regimen were highly effective against Ascaris lumbricoides but only moderately effective against Trichuris trichiura and Necator americanus.

Reevaluation de l'efficacite et de la tolerance du Pamoate de Pyrantel dans le traitement de la necatorose au Senegal

L'etude de la tolerance et de l'efficacite du Pamoate de Pyrantel (Vermintel) s'est deroulee au Senegal dans la region de Ziguinchor et a interesse 40 patients parasites par N. americanus. Le Pamoate de Pyrantel a ete administre a la dose de 20 a 25 mg/kg de pc par jour durant 2 jours consecutifs; soit sous forme de comprimes; soit sous forme de suspension buvable. La tolerance du produit a ete excellente dans 65 pour cent des cas et bonne chez les autres (35 pour cent); puisque les effets secondaires ont ete benins et de breve duree. En ce qui concerne l'efficacite du traitement; elle a ete excellente puisque les signes imputables a la necatorose avaient disparu dans 90;4 pour cent des cas a l'examen de controle a J14. Sur le plan parasitologique; en depit d'un taux de guerison de 20;4 pour cent a J14; l'efficacite peut etre consideree comme bonne. En effet; un taux de reduction du nombre d'oeufs excretes de 90;6 pour cent a ete obtenu chez les sujets non gueris; ce qui correspond a une baisse importante de la charge parasitaire. Les resultats ainsi obtenus dans le traitement de la necatorose au Senegal peuvent etre consideres comme satisfaisants. Ils pourraient cependant etre ameliores en administrant des doses plus importantes

Effect of single-dose albendazole and single-dose mebendazole on Necator americanus.

One hundred two children (43 males and 59 females) aged 6 to 14 years with positive stool examination by Kato-Katz and/or Harada-Mori culture techniques for N. americanus, were randomly divided into two groups. Group I with 48 children were treated with a single dose albendazole, 400 mg. Group II, 54 children, received a single dose mebendazole, 600 mg. After treatment, repeated stool examination was performed on Day 14, Day 21 and Day 28. The children were considered cured when stool examination was negative on all three occasions by both methods. The cure rate was 64% in Group I and 11% in Group II. The difference was statistically significant (p less than 0.05). The eggs reduction rate was 98% in Group I and 95% in Group II. Mild and transient side effects such as nausea, dizziness and headache were observed in both groups. Albendazole, 400 mg, as a single dose treatment was shown to be superior to mebendazole, 600 mg, single dose for the mass treatment of hookworm infection, especially that of Necator americanus, in an endemic area.

Comparative study of different doses of mebendazole in hookworm infection.

Sixty six children (40 males, 26 females) aged from 4 to 14 years with hookworm infection were treated with mebendazole. Thirty one and 35 children were treated with mebendazole 300 mg single dose and 600 mg conventional regimen respectively. Stool examination by Kato-Katz technique were done for 3 consecutive days before treatment and on day 14-16, 21-23 after treatment. The cure rate with 300 mg mebendazole was 16.1% with 90.9% egg reduction while 600 mg mebendazole gave 91.4% cure rate with 99.5% egg reduction. No side effects were observed in all children. Four hundred and six adult worms were identified, 99% were Necator Americanus, 0.5% Ancylostoma duodenale and 0.5% Ancylostoma ceylanicum.

Dosis única antihelmíntica: estudio comparativo con dosis única, entre oxantel/pirantel y albendazol en ascariasis, tricocefalosis y uncinarias / Single antihelminthic dosage: comparative study with single doses between oxantel/pirantel and albendazole in ascariasis, trichocephaliasis and uncinarias

Se presentan los resultados de un estudio comparativo entre el oxantel-pirantel y el albendazol, en un grupo de 60 años parasitados por alguno de los siguientes helmintos transmitidos por el suelo: áscaris, tricocéfalos y uncinarias. Los medicamentos fueron administrados en dosis única: el oxantel-pirantel a razón de 20 miligramos-/kilogramo de peso, y el albendazol en dosis total de 400 milígramos. Se observaron excelentes resultados con ambos medicamentos en el tratamiento de la ascariasis. En la curación parasitológica de la uncinariasis el oxantel-pirantel exhibió superioridad (85.7%) de los casos tratados) sobre el albendazol (66.7% de los casos tratados); y, en lo que respecta a la reducción en el número de huevecillos, ambas drogas demostraron ser de utilidad. En las tricocefalosis de grados, I, II y III la curación obtenida con oxantel-pirantel fué superior. En relación a la disminución de huevecillos en las heces, existió una ligera superioridad por parte del oxantel-pirantel. En el grado IV de tricocefalosis, el efecto terapéutico de ambos medicamentos mostró muy poca utilidad cuando son suministrados en dosis única. Se propone una escala de los grados de parasitosis para ser utilizada en la evaluación de drogas antihelmínticas

Eficacia a los seis meses de diferentes esquemas terapeuticos de mebendazol en las infecciones por A. lumbricoides, ancylostomidae SP y T. trichiura en niños de edad escolar / Efficacy after 6 months of different therapeutic schedules of mebendazole in infections by A. lumbricoides, Ancylostomidae sp and T. trichiura in school children

En una investigación prospectiva con grupo control llevada a cabo en 386 escolares de un barrio periférico de la ciudad de Santa Cruz, se evidenció la eficacia del mebendazol sobre la reducción a los seis meses de las cargas parasitarias para Ancylostomidae sp. y T. trichiura, mientras que no se observó tal efecto para A. lumbricoides. El resultado fue similar entre el esquema clásico (3 x 2 tab. de 100 mg) y el de la dosis única de 300 mg. (3 tab.)

Oxantel-pyrantel pamoate for the treatment of soil-transmitted helminths.

A mixture of oxantel-pyrantel pamoate was given to 147 primary school children. A single daily dose of 15 mg per kg body weight was administered to cases with Ascaris lumbricoides and Trichuris trichiura infections. The same single daily dose was given for three consecutive days to 10 cases with hookworm infections. The cure rate was 93.7% for ascariasis and the egg reduction rate was 98.2%. A cure rate and an egg reduction rate for trichuriasis was 70.2% and 86.5% respectively. All cases with hookworm infection were cured. Side effects were light and did not cause any anxiety.