Critical analysis of cystic echinococcosis control programs and praziquantel use in South America, 1974-2010 / Análisis crítico de los programas de control de la equinococosis quística y uso del prazicuantel en América del Sur, 1974-2010

Cystic echinococcosis (CE) is one of the most prevalent zoonoses in Argentina, Brazil, Chile, Peru, and Uruguay. Control programs in South America were originally modeled after programs developed in insular territories, such as Tasmania and New Zealand. The advent and proven effectiveness of praziquantel, plus the experience of insular models, produced high expectations for rapid advances; however, after 30 years of praziquantel use, no endemic area in South America has obtained eradication. In fact, only modest gains in CE control have been made and impact on prevalence among humans has been slight. A major impediment has been the infrastructure needed to administer praziquantel to dogs in rural areas 8 times per year over numerous years, a requirement for rapid attack stage 1. Such an infrastructure has not been financially or politically sustainable in endemic areas, which tend to be the poorest. On the other hand, certain areas in Argentina have had success with simple and economically viable alternatives. Based primarily on continuous field work supported by the local community, these strategies have significantly decreased transmission to humans, the health sector's main objective. In addition, new possibilities and tools, such as the EG95 vaccine, are being evaluated; as are early detection and treatment of asymptomatic carriers.

La equinococosis quística (EQ) es una de las zoonosis más prevalentes en Argentina, Brasil, Chile, Perú y Uruguay. Los programas de control en América del Sur fueron originalmente hechos a imitación de los programas desarrollados en territorios insulares, como Tasmania y Nueva Zelandia. El advenimiento y la eficacia comprobada del prazicuantel, sumados a la experiencia de los modelos insulares, dieron lugar a altas expectativas de adelantos rápidos; sin embargo, después de 30 años de uso del prazicuantel, ninguna zona endémica en América del Sur ha logrado la erradicación de la enfermedad. De hecho, solo se han obtenido avances moderados en el control de la EQ, y su repercusión sobre la prevalencia en seres humanos ha sido leve. Un impedimento mayor ha sido la infraestructura necesaria para administrar el prazicuantel a los perros en zonas rurales 8 veces por año durante varios años, un requisito para el estadio 1 de ataque rápido. Tal infraestructura no ha sido sostenible desde el punto de vista económico o político en las zonas endémicas, que tienden a ser las más pobres. Por otro lado, ciertas áreas de la Argentina han tenido éxito con opciones sencillas y económicamente viables. Basadas principalmente en el trabajo continuo en el terreno apoyado por la comunidad local, estas estrategias han reducido significativamente la transmisión a los seres humanos, que es el objetivo principal del sector de la salud. Además, se están evaluando nuevas posibilidades y herramientas, como la vacuna EG95, al igual que la detección temprana y el tratamiento de los portadores asintomáticos.

Effect of a single dose of diethylcarbamazine, albendazole or both on the clearance of Wuchereria bancrofti microfilariae and antigenaemia among microfilaria carriers: A randomized trial.

Background. Lymphatic filariasis is a major vector-borne parasitic disease. The global programme to eliminate lymphatic filariasis was launched in 1997 and currently over 570 million people are covered under it in 48 countries. Mass annual single-dose drug administration of diethylcarbamazine (DEC), co-administrated with albendazole for 5–6 years and mass distribution of diethylcarbamazine-fortified salt are the two strategies for elimination of filariasis. Methods. Asymptomatic volunteers residing in Puducherry, India were screened for microfilaria (mf) by examining nocturnal thick blood smears. Those testing positive were randomly assigned to receive a single dose of DEC (6 mg/kg body weight) or albendazole 400 mg or both. Participants were hospitalized for 5 days. Membrane filtration count was used to assess microfilaraemia and ELISA (Og4C3) assay to measure circulating filarial antigens (CFA). Measurements were done before treatment and at 1, 2 and 3 years post-treatment. Viability of the adult worms was assessed by looking for the filarial dance sign (FDS) using ultrasound examination of the scrotum in men with hydrocele. Results. Fifty-four microfilaraemic individuals were studied. The mf prevalence started decreasing only by day 180 posttreatment in the DEC group but much earlier in the other two groups (day 30 in the albendazole and day 90 in the DEC with albendazole group). The decrease in mf was marginal (17.6%, 26.3% and 27.8%, respectively) by the end of year 1 posttreatment, but significant (96.7%, 78.6% and 93.3%, respectively) by the end of year 2 post-treatment (p<0.05). By the end of year 3, the level decreased to 80% in the DEC, 90% in the albendazole and to 100% in the DEC and albendazole groups. However, the mf intensity decreased © The National Medical Journal of India 2010 Vector Control Research Centre, Department of Health Research (ICMR), Indira Nagar, Puducherry 605006, India S. L. HOTI, S. P. PANI, P. VANAMAIL, K. ATHISAYA MARY, L. K. DAS, P. K. DAS Correspondence to S. L. HOTI; slhoti@yahoo.com significantly (by 39%; p<0.05) by day 7 post-treatment in both the DEC and DEC with albendazole groups, but only by day 30 in the albendazole group. In all the drug groups, the prevalence as well as intensity of CFA returned to pretreatment levels by the end of year 3 post-treatment. Conclusion. Annual single-dose administration of all the 3 drug regimens significantly reduced antigenaemia levels. There were no significant differences in the efficacy and overall pattern of CFA clearance between the 3 drug regimens.

Kinetics of microfilaraemia & antigenaemia status by Og(4)C(3) ELISA in bancroftian filariasis.

BACKGROUND & OBJECTIVE: Bancroftian filariasis caused by Wuchereria bancrofti is endemic in many parts of India. In recent years diagnosis of W. bancrofti infection has been revolutionized with the availability of filarial antigen tests, which is important in monitoring success of chemotherapy. We carried out this study to measure microfilariaemia and antigenemia levels in bancroftian microfilariae (mf) carriers at 1 yr follow up after chemotherapy, in lymphoedema patients and in endemic controls from a filariasis endemic area in Tamil Nadu State using Og(4)C(3) ELISA to identify the best marker to assess success of chemotherapy. METHODS: Serum samples were collected from 30 bancroftian microfilaremic (Mf) carriers pre-treatment and at sequential intervals (7,30,60,90,180 and 365 days) following treatment with diethylcarbamazine (DEC:6mg/kg body weight, single dose), 30 lymphoedema patients (without treatment) at periodic intervals, and 68 control subjects (24 endemic normal subjects in filariasis endemic area in Tamil Nadu State, 24 non-endemic normal subjects residing in Chandigarh, India; 5 brugian filariasis, 5 endemic control subject in brugian filariasis endemic area and 10 other disease controls). The circulating antigen of W. bancrofti was measured quantitatively using Og(4)C(3) ELISA kit. RESULTS: In Mf carriers, there was no significant difference in microfilariae count in pre- and post-treatment (PT) samples till day 30 while significant differences were observed in pre- and sequentially collected post-treatment (PT) samples day 60 to 180 (P<0.001), day 365 (P<0.005). However, there was no significant difference in antigenaemia levels between pre-treatment (day 0) and PT samples collected on day 7 onwards till day 365. Though of the 19 patients who could be followed up till 365 days PT, 4 (21%) were amicrofilaraemic, none became antigen negative. No significant difference was found in antigenaemia levels in sequentially collected samples from lymphoedema patients. Significant differences were observed in antigenaemia levels in samples collected at the start of study in mf carriers as compared to lymphoedema patients and endemic normal subjects (P<0.001). Subjects (non-endemic control) residing in filariasis free area (24), brugian endemic area (5), B.malayi infected patients (5) and patients with other parasitic diseases (10) were found antigen negative. INTERPRETATION & CONCLUSION: Annual single dose of DEC therapy alone may not result in complete clearance of infection and detection of antigenaemia rather than microfilaraemia may be taken into consideration as an indicator of successful chemotherapy. The study supports the earlier view that filarial antigenaemia is relatively common in amicrofilaraemic and asymptomatic subjects in endemic areas and further studies are needed to determine the clinical significance, prognosis and effective management of such infections in endemic areas.

Tolerability and efficacy of a three-age class dosage schedule of Diethylcarbamazine citrate (DEC) in the treatment of microfilaria carriers of Wuchereria bancrofti and its implications in mass drug administration (MDA) strategy for elimination of lymphatic filariasis (LF).

A six-age class dosage schedule of Diethylcarbamazine (DEC) of 50mg (1-2 years), 100mg (3-4 years), 150mg (5-8 years), 200mg (9-11 years), 250mg (12-14 years) and 300mg for above 14 years is being adopted for annual single dose MDA for LF elimination treat Wuchereria bancrofti microfilaria carriers. In order to increase the community compliance as well as to make the distribution easier during MDA, a revised 3 age class dosage schedule of 100mg (2-4 years), 200mg (5-14 years) and 300mg for above 14 years was evaluated for its tolerability and efficacy. By this change, it was observed that the 4-8 years age class is receiving 50 mg higher and 11-14 years age class is receiving 50mg lesser dose compared to the earlier class schedule. Therefore, the safety aspect in the age class of 4-8 years and efficacy component in the age class of 11-14 years were assessed. Apparently "healthy" asymptomatic microfilaraemic volunteers between the age class of 4-8 and 11-14 years were recruited for the study. The incidence of side reaction in the 4-8 years age class was 50.0% with 150mg dose and 66.7% with 200mg (P>0.05). No life threatening adverse reactions was observed in any dosage schedule. Fever, headache and myalgia, the predominant adverse reactions were mild and similar in both schedules. The mean intensity of the three major specific adverse reactions (fever, headache and myalgia) also did not differ significantly (P>0.05). For the purpose of LF elimination, efficacy in terms of reduction in mean microfilaria load is important. In the 11-14 year age class considerable reduction in the geometric mean density (GMD) was observed by day 90 and 180 post-therapy in both groups (250mg group and 200mg group) compared to pre-therapy level. By day 360 post-therapy, the difference was statistically not significant (P>0.05) (reduction of 72.2% in 250mg and 69.6% reduction in 200mg). The reductions in GMD were statistically significant when compared to pre-therapy levels in both the old (250mg) and new (200mg) doses. Thus, three- age class dosage schedule is as safe and efficacious as the six- age class schedule.

Antiviral Therapy in Hepatitis B Carriers Undergoing Immunosuppressive Treatment or Cytotoxic Chemotherapy / 대한간학회지

No abstract available.

Treatment of microfilaraemics with DEC and its effect on vector infection and infectivity in tribal and non-tribal areas of Bankura district, West Bengal, India.

Single course DEC treatment (6 mg/kg body weight/day for 12 days) was administered to 66 tribal and 442 non-tribal microfilaria (mf) carriers detected through a Filariasis survey in Bankura district, West Bengal, India. All the mf carriers remained amicrofilaraemic on 22nd, 180th and 365th post-treatment day. As a result of DEC treatment to the mf carriers, vector (Culex quinquefasciatus) infection rate in tribal study areas reduced from 2.06% to 1.07%. Infectivity rate was "nil" both before and after treatment. In non-tribal study areas, vector infection rate reduced from 4.33% to 2.22% and infectivity rate from 0.51% to 0.29%.

Community perception of Malayan filariasis in the rural areas of Cherthala Taluk of Kerala State, south India.

Lymphatic filariasis, one of the major public health problems can be controlled with the active participation of the community. The human factors involved in the disease transmission are important. The knowledge on the community perception and practice is essential to develop community oriented control programmes. A descriptive study was conducted in the filariasis endemic area of Cherthala, Kerala State, India, to identify the level of people's perception on Malayan filariasis. Two methods namely, interviews and uncontrolled observation were used in the study. A total of 450 respondents (150 microfilaria carriers, 150 chronic patients and 150 normals) were interviewed. The study results showed that majority of the respondents (86.7%) were aware that the disease was caused by a parasite and 93.6% had awareness on transmission of the disease through mosquito bite. The knowledge on the preventive measures against filariasis was also high (78.2%) among the sampled respondents. The strategy for community mobilization in filariasis control programme is discussed in view of high awareness.

Efficacy of a single dose treatment of Wuchereria bancrofti microfilaria carriers with diethylcarbamazine in Matara, Sri Lanka.

OBJECTIVE: To test the efficacy of diethylcarbamazine DEC single dose regimen of 6 mg/kg body weight (bw) on a sample of Wuchereria bancrofti microfilaria (mf) carriers in Matara. DESIGN: 6 mg/kg bw DEC dose in 50 mg tablets given under direct observation to the subjects at 23.00 hours after pre-treatment blood collection for mf counts. Post-treatment mf counts were at 1, 2 weeks and 1, 3, 6, 12 months. SUBJECTS: 31 asymptomatic mf carriers, 14 males, age range 6 to 62 years. RESULTS: Treatment resulted in 89 to 97% success rate, 19 to 28% cure rates and 74 to 80% reduction in mf density. There was no difference statistically in the success rate and cure rate at 6 and 12 months. The effect of DEC treatment at 6 and 12 months compared by sex, age group and pre-treatment mf level showed no difference. 64.5% of the carriers treated had at least one mild adverse reaction. Rates of the common reactions were 41.9% fever, 22.6% headache and 16.1% joint pains. CONCLUSION: A new mass treatment program has been initiated by the national Antifilariasis Campaign using the single dose DEC 6 mg/kg bw regimen. The satisfactory reduction in mf density at 6 and 12 months following DEC single dose treatment we observed provides support for this program.

Role of bacterial flora in the pathogenesis & management of atopic dermatitis.

The carriage state of Staphylococcus aureus and its role in the pathogenesis and management of atopic dermatitis were evaluated in 50 patients, aged 3 months to 12 yr. An equal number of age and sex matched controls were also studied. The positivity of Staph.aureus in patients with atopic dermatitis was 50 per cent from eczematous skin, 34 per cent from anterior nares and 26 per cent from normal skin. In controls, the comparative figures were 14 per cent from anterior nares and 10 per cent from normal skin. After institution of oral erythromycin or cloxacillin therapy (according to sensitivity), the colony counts dropped to 18 per cent from eczematous skin, 14 per cent from anterior nares and 8 per cent from normal skin after one week and to zero after 3 wk. This was associated with significant clinical improvement. The results of this study suggest that Staph. aureus aggravates the eczematous process in patients with atopic dermatitis and antibiotics decrease the severity and are useful in long term prognosis of the disease.

Salmonella carriage rate amongst school children--a three year study.

As a part of three-years epidemiological survey of salmonellosis in South Kanara District, a southwest coastal region of India, an attempt was made to determine the human Salmonella carriage rate during the period between 1981 to 1983. One thousand and two asymptomatic school children 5 to 15 years of age, 42 restaurant employees and 17 dairy workers formed the subjects of this bacteriological study. The Salmonella carriage rate among healthy school children from a single fecal sampling was 1% and no Salmonellae were recovered from the feces of restaurant and dairy workers. Ten school children excreted Salmonellae which belonged to 6 different serotypes-Salmonella oslo, S. ohio, S. typhimurium, S. urbana, S. cerro and S. derby; S. oslo and S. ohio were the most frequent serotypes. No-S. typhi, S. paratyphi A or S. paratyphi B were recovered. All Salmonella strains recovered during this study were dual or multiple drug resistant, sulfadiazine and tetracycline resistance being commonly observed. The significance of excretion of potentially pathogenic, drug resistant Salmonellae by symptomless school children is discussed from public health point of view.

Influence of diethylcarbamazine on the patent period of infection in periodic Brugia malayi.

The patent period of infection which reflects the fecundic life span of the adult female worm was estimated for periodic B. malayi in south India by using immigration death model. Longitudinal data on natural loss of infection or that due to different degrees of DEC pressure in a cohort population of microfilaria carriers after a three years period, were used for the estimations. The patent period of infection was estimated to be 3.45 yr under natural conditions (without DEC therapy), which was reduced to 1.67 yr following one full course of selective therapy (6 mg/kg body wt/day for 12 days). When selective therapy was supplemented with four rounds of biannual single-dose mass DEC therapy (6 mg/kg body wt) the patent period was further reduced to 1.34 yr. The proportion loss of infection was relatively higher in microfilaria carriers who discontinued DEC selective therapy, when compared to natural loss. The percentage reduction in the mean microfilaria count was observed to decrease with increasing DEC pressure. Neither sex nor the age of the host was found to influence the fecundic life span or the survival of female adult worm.

Cefalosporinas de 3ª generación en el tratamiento de la meningitis purulenta con portación faríngea del agente causal / Cefalosporine of 3rd. generation in the treatment of the purulent meningitis with faríngeal carrier of causal agent

H. influenzae y N. meningitidis son los agentes causales más frecuentes de meningitis purulenta en niños en nuestro país y ambos presentan alta contagiosidad. Una fuente potencial de infecciones la constituyen los portadores faríngeos. Con el objeto de evaluar la eficacia de dos cefalosporinas: cefotaxima y ceftriaxona, para erradicar estos agentes de la faringe de niños con meningitis, se realizó un estudio prospectivo en dos hospitales de Santiago, Exequiel González Cortés y Luis Calvo Mackenna, entre abril de 1989 y diciembre de 1990. Se estudiaron 40 pacientes con meningitis documentada bacteriológicamente a quienes se le practicó frotis faríngeo al ingreso al hospital y una vez completado el tratamiento antimicrobiano, efectuando cultivos en medios adecuados para crecimiento de Haemophilus y Neisseria meningitidis. En 30 a 40 niños se practicó en forma paralela frotis nasal. En los 25 pacientes con meningitis por Hib se aisló el agente de las secreciones nasofaríngeas y las cepas de Haemophilus aisladas fueron serotipo b, biotipo 1, con 23,5% de resistencia a ampicilina (6 cepas), mediada por la producción de betalactamasa. Se realizó el perfil plasmidial en 7 cepas aisladas de faringe, y su correspondiente en LCR observándose homología. Ambos esquemas terapéuticos, cefotaxima por 14 días en el hospital EGC y ceftriaxona por 7 en el LCM, resultaron igualmente eficaces para erradicar H. influenzae de la nasofaringe, con 100% de efectividad. En ninguno de los 15 niños con meningitis meningocócica, se aisló este agente de la faringe, ni al ingreso ni al finalizar el tratamiento

Plano integrado de saúde no combate a esquistossomose no Estado do Maranhäo / Compulsive health plan in the compaign against schistosomiasis in the State of Maranhäo, Brasil

O objetivo principal deste plano integrado foi o cumprimento da fase de ataque do Programa Especial de Controle da Esquistossomose (coproscopia e tratamento dos portadores) em conjunto com os demais órgäos componentes do Conselho Estadual de Saúde e com o envolvimento da comunidade, visando maior rendimento, segurança e aceitaçäo das açöes. Os índices alcançados de exames e tratamentos demonstram a possibilidade de se obter através dessas açöes integradas, a reduçäo da incidência da endemia a níveis suportáveis, até que sua erradicaçäo seja factível