How Does the Proportion of Never Treatment Influence the Success of Mass Drug Administration Programs for the Elimination of Lymphatic Filariasis?

BACKGROUND

Mass drug administration (MDA) is the cornerstone for the elimination of lymphatic filariasis (LF). The proportion of the population that is never treated (NT) is a crucial determinant of whether this goal is achieved within reasonable time frames.

METHODS

Using 2 individual-based stochastic LF transmission models, we assess the maximum permissible level of NT for which the 1% microfilaremia (mf) prevalence threshold can be achieved (with 90% probability) within 10 years under different scenarios of annual MDA coverage, drug combination and transmission setting.

RESULTS

For Anopheles-transmission settings, we find that treating 80% of the eligible population annually with ivermectin + albendazole (IA) can achieve the 1% mf prevalence threshold within 10 years of annual treatment when baseline mf prevalence is 10%, as long as NT <10%. Higher proportions of NT are acceptable when more efficacious treatment regimens are used. For Culex-transmission settings with a low (5%) baseline mf prevalence and diethylcarbamazine + albendazole (DA) or ivermectin + diethylcarbamazine + albendazole (IDA) treatment, elimination can be reached if treatment coverage among eligibles is 80% or higher. For 10% baseline mf prevalence, the target can be achieved when the annual coverage is 80% and NT ≤15%. Higher infection prevalence or levels of NT would make achieving the target more difficult.

CONCLUSIONS

The proportion of people never treated in MDA programmes for LF can strongly influence the achievement of elimination and the impact of NT is greater in high transmission areas. This study provides a starting point for further development of criteria for the evaluation of NT.

Diethylcarbamazine elicits Ca2+ signals through TRP-2 channels that are potentiated by emodepside in Brugia malayi muscles

Filarial nematode infections are a major health concern in several countries. Lymphatic filariasis is caused by Wuchereria bancrofti and Brugia spp. affecting over 120 million people. Heavy infections can lead to elephantiasis, which has serious effects on individuals' lives. Although current anthelmintics are effective at killing microfilariae in the bloodstream, they have little to no effect against adult parasites found in the lymphatic system. The anthelmintic diethylcarbamazine is one of the central pillars of lymphatic filariasis control. Recent studies have reported that diethylcarbamazine can open transient receptor potential (TRP) channels in the muscles of adult female Brugia malayi, leading to contraction and paralysis. Diethylcarbamazine has synergistic effects in combination with emodepside on Brugia, inhibiting motility: emodepside is an anthelmintic that has effects on filarial nematodes and is under trial for the treatment of river blindness. Here, we have studied the effects of diethylcarbamazine on single Brugia muscle cells by measuring the change in Ca2+ fluorescence in the muscle using Ca2+-imaging techniques. Diethylcarbamazine interacts with the transient receptor potential channel, C classification (TRPC) ortholog receptor TRP-2 to promote Ca2+ entry into the Brugia muscle cells, which can activate Slopoke (SLO-1) Ca2+-activated K+ channels, the putative target of emodepside. A combination of diethylcarbamazine and emodepside leads to a bigger Ca2+ signal than when either compound is applied alone. Our study shows that diethylcarbamazine targets TRP channels to promote Ca2+ entry that is increased by emodepside activation of SLO-1 K+ channels.

The search for better treatment strategies for mansonellosis: an expert perspective

INTRODUCTION

Four species of the Mansonella genus infect millions of people across sub-Saharan Africa and Central and South America. Most infections are asymptomatic, but mansonellosis can be associated with nonspecific clinical manifestations such as fever, headache, arthralgia, and ocular lesions (M. ozzardi); pruritus, arthralgia, abdominal pain, angioedema, skin rash, and fatigue (M. perstans and perhaps Mansonella sp. 'DEUX'); and pruritic dermatitis and chronic lymphadenitis (M. perstans).

AREAS COVERED

We searched the PubMed and SciELO databases for publications on mansonelliasis in English, Spanish, Portuguese, or French that appeared until 1 May 2023. Literature data show that anthelmintics - single-dose ivermectin for M. ozzardi, repeated doses of mebendazole alone or in combination with diethylcarbamazine (DEC) for M. perstans, and DEC alone for M. streptocerca - are effective against microfilariae. Antibiotics that target Wolbachia endosymbionts, such as doxycycline, are likely to kill adult worms of most, if not all, Mansonella species, but the currently recommended 6-week regimen is relatively impractical. New anthelmintics and shorter antibiotic regimens (e.g. with rifampin) have shown promise in experimental filarial infections and may proceed to clinical trials.

EXPERT OPINION

We recommend that human infections with Mansonella species be treated, regardless of any apparent clinical manifestations. We argue that mansonellosis, despite being widely considered a benign infection, may represent a direct or indirect cause of significant morbidity that remains poorly characterized at present.

A Case of Tropical Pulmonary Eosinophilia With Incomplete Response to Diethylcarbamazine Therapy

Tropical pulmonary eosinophilia (TPE) is a specific pulmonary manifestation of lymphatic filariasis. There is overwhelming infiltration of eosinophils in the lung parenchyma in response to microfilaria. The characteristic features include paroxysmal respiratory symptoms, strikingly high blood eosinophil count, elevated level of immunoglobulin (Ig) E along with high titer of anti-filarial antibody. Treatment with diethylcarbamazine (DEC) has an excellent favorable response. However, recovery may often be incomplete. We present a case of a 36-year-old man with TPE who had complete symptomatic improvement after a three-week course of DEC, but only a partial response in radiological and pulmonary function abnormalities.

[A Strategic Partnership for Medicine Creation and Access to Medicine for Neglected Tropical Diseases]

Neglected tropical diseases (NTDs) are communicable diseases that are uncommon in developed countries but epidemic in developing countries of the tropical and subtropical regions around the world. One of the important contributions expected of pharmaceutical companies is the development and provision of drugs effective against NTDs. Firstly, Eisai has distributed at price zero to endemic countries worldwide diethylcarbamazine (DEC) tablets for patients suffering with lymphatic filariasis (LF). Eisai's efforts toward improving global health have resulted in a rich portfolio of assets addressing six infectious diseases: malaria, tuberculosis, Chagas disease, LF, leishmaniasis, and mycetoma. As the most advanced project, Eisai has developed E1224, which is available in both intravenous and oral formulations, and delivers ravuconazole, the active form of fosravuconazole, with a long plasma half-life. The first clinical trials of E1224 for Chagas disease have already been completed, led by the Drugs for Neglected Diseases initiative (DNDi). As a result, parasite clearance was observed with E1224 during the treatment phase, but parasite regrowth was observed after the end of drug administration. On the other hand, a clinical trial for eumycetoma in collaboration with DNDi is ongoing supported by the Global Health Innovative Technology (GHIT) Fund. In this manner, Eisai will continue its Medicine Creation research projects in collaboration with various Product Development Partnerships (PDPs) and academia.

Membranoproliferative glomerulonephritis: A rare presentation of occult filariasis

Parasitic infections do not usually present with rapidly progressive renal failure but can provoke glomerular lesions which are mostly proliferative. In filarial infection, glomerular involvement is usually mild and transient, and presentation with renal failure is rare. We report occult filariasis presenting as rapidly progressive renal failure due to immune-complex mediated membranoproliferative glomerulonephritis. Our patient responded to treatment with diethylcarbamazine and a short course of steroid. This case highlights the importance of thorough workup to identify the cause and consideration of filariasis in an endemic area.

Efficacy and Safety of a Single Dose of Ivermectin, Diethylcarbamazine, and Albendazole for Treatment of Lymphatic Filariasis in Côte d'Ivoire: An Open-label Randomized Controlled Trial

Background

Improved drug regimens are needed to accelerate elimination of lymphatic filariasis in Africa. This study determined whether a single co-administered dose of ivermectin plus diethylcarbamazine plus albendazole [IDA] is noninferior to standard 3 annual doses of ivermectin plus albendazole (IA) used in many LF-endemic areas of Africa.

Methods

Treatment-naive adults with Wuchereria bancrofti microfilaremia in Côte d’Ivoire were randomized to receive a single dose of IDA (n = 43) or 3 annual doses of IA (n = 52) in an open-label, single-blinded trial. The primary endpoint was the proportion of participants who were microfilaria (Mf) negative at 36 months. Secondary endpoints were Mf clearance at 6, 12, and 24 months; inactivation of adult worm nests; and safety.

Results

At 36 months posttreatment with IDA, 18/33 (55%; 95% CI, 38–72%) cleared Mf versus 33/42 (79%; 67–91%) with IA (P = .045). At 6 and 12 months IDA was superior to IA in clearing Mf (89% [77–99%] and 71% [56–85%]), respectively, versus 34% (20–48%) and 26% (14–42%) (P < .001). IDA was equivalent to IA at 24 months (61% [45–77%] vs 54% [38–72%]; P = .53). IDA was superior to IA for inactivating adult worms at all time points. Both treatments were well tolerated, and there were no serious adverse events.

Conclusions

A single dose of IDA was superior to 2 doses of IA in reducing the overall Mf burden by 24 months. Reinfection may have contributed to the lack of sustained clearance of Mf with IDA.

Clinical Trials Registration

NCT02974049.

Safety and Tolerability of Mass Diethylcarbamazine and Albendazole Administration for the Elimination of Lymphatic Filariasis in Kenya: An Active Surveillance Study

Preventive chemotherapy with diethylcarbamazine citrate (DEC) and albendazole (ALB) is the core intervention strategy to eliminate lymphatic filariasis (LF). We conducted a large-scale prospective active safety surveillance study to identify the incidence, type, severity, and risk factors for adverse events (AEs) following mass drug administration (MDA) of single-dose DEC and ALB in 10,010 participants from Kilifi County, Kenya. AEs were actively monitored and graded at 24 h, 48 h, and on day 7 Post-MDA. Out of 10,010 enrolled study participants, 1621 participants reported a total of 3102 AEs during a seven-day follow-up. The cumulative incidence of AEs was 16.2% (95% CI, 15.5–16.9%). The proportion of participants who experienced one, two, or ≥three types of AEs was 9.2%, 4.6%, 2.4%, respectively. AEs were mild (87.3%), moderate (12.4%), and severe (0.3%) and resolved within 72 h. The five most common AEs were dizziness (5.9%), headache (5.6%), loss of appetite (3.3%), fever (2.9%), and drowsiness (2.6%). Older age, taking concurrent medications, ≥three tablets of DEC, and type of meal taken before MDA were significant predictors of AEs. One in six participants experienced systemic mild-to-moderate severity grading and transient AEs. DEC and ALB co-administration for the elimination of LF is generally safe and well-tolerated.

A randomized, placebo-controlled, double-blind pilot study of single-dose humanized anti-IL5 antibody (reslizumab) for the reduction of eosinophilia following diethylcarbamazine treatment of Loa loa infection

BACKGROUND

Diethylcarbamazine citrate (DEC) treatment of loiasis is complicated by adverse reactions that are correlated with the number of circulating microfilariae (mf). The cause of these reactions is unknown, but they are accompanied by a dramatic interleukin-5 (IL-5)-dependent increase in eosinophilia and evidence of eosinophil activation.

METHODS

To explore the role of IL-5 driven eosinophilia in post-DEC reactions, 8 adults with confirmed loiasis and &5000 mf/mL blood were enrolled in a randomized, double-blind, placebo-controlled trial of the humanized anti-IL-5 antibody, reslizumab, (1.0 mg/kg IV) administered 3 to 7 days prior to initiation of DEC treatment (9 mg/kg/day for 21 days). The primary endpoint was the reduction in absolute eosinophil count (AEC) during the first week of DEC treatment.

RESULTS

Baseline characteristics were comparable between the two groups. Single dose reslizumab lowered the AEC by 77% prior to initiation of DEC therapy (vs. 12% in the placebo group, p&0.05). More importantly, AEC remained below baseline in the first week of DEC treatment in all subjects who received reslizumab and in none of the placebo subjects. Mf clearance occurred within 2 days of initiation of DEC in all 7 mf-positive subjects. Mild to moderate adverse events were seen in all 8 subjects and were not significantly different between the groups.

CONCLUSIONS

In summary, although reslizumab was able to blunt peripheral eosinophilia post-DEC treatment in subjects with loiasis and had no effect on microfilarial clearance, the reduction in AEC appeared to have been insufficient to prevent post-treatment AEs.

Efficacy of High-Dose Albendazole with Ivermectin for Treating Imported Loiasis, Italy

We describe the outcomes of 16 cases of imported loiasis in Italy. Patients had microfilaremia <20,000/mL and were treated with high-dose albendazole for 28 days and a single dose of ivermectin. This combination might be an effective treatment option in nonendemic areas, when diethylcarbamazine, the drug of choice, is not available.

Effects of diethylcarbamazine and ivermectin treatment on Brugia malayi gene expression in infected gerbils (Meriones unguiculatus)

Lymphatic filariasis (LF) threatens nearly 20% of the world’s population and has handicapped one-third of the 120 million people currently infected. Current control and elimination programs for LF rely on mass drug administration of albendazole plus diethylcarbamazine (DEC) or ivermectin. Only the mechanism of action of albendazole is well understood. To gain a better insight into antifilarial drug action in vivo, we treated gerbils harbouring patent Brugia malayi infections with 6 mg kg⁻¹ DEC, 0.15 mg kg⁻¹ ivermectin or 1 mg kg⁻¹ albendazole. Treatments had no effect on the numbers of worms present in the peritoneal cavity of treated animals, so effects on gene expression were a direct result of the drug and not complicated by dying parasites. Adults and microfilariae were collected 1 and 7 days post-treatment and RNA isolated for transcriptomic analysis. The experiment was repeated three times. Ivermectin treatment produced the most differentially expressed genes (DEGs), 113. DEC treatment yielded 61 DEGs. Albendazole treatment resulted in little change in gene expression, with only 6 genes affected. In total, nearly 200 DEGs were identified with little overlap between treatment groups, suggesting that these drugs may interfere in different ways with processes important for parasite survival, development, and reproduction.

Lymphatic Filariasis Presenting as a Swelling over the Upper Arm: A Case Report

Filariasis continues to be one of the endemic problems worldwide with 40% of the cases in India. We report a case of lymphatic filariasis in a 32-year old female who presented with a non-tender swelling over left upper arm. Blood sample showed no eosinophilia while the FNAC was diagnostic of W. bancrofti. Patient responded well with oral diethylcarbamazine. High index of suspicion of filariasis is indicated when dealing with a swelling of unknown cause especially in filariasis endemic areas.

Posttreatment Reactions After Single-Dose Diethylcarbamazine or Ivermectin in Subjects With Loa loa Infection

Background

Severe adverse reactions have been observed in individuals with Loa loa infection treated with either diethylcarbamazine (DEC), the drug of choice for loiasis, or ivermectin (IVM), which is used in mass drug administration programs for control of onchocerciasis and lymphatic filariasis in Africa. In this study, posttreatment clinical and immunologic reactions were compared following single-dose therapy with DEC or IVM to assess whether these reactions have the same underlying pathophysiology.

Methods

Twelve patients with loiasis and microfilarial counts <2000 mf/mL were randomized to receive single-dose DEC (8 mg/kg) or IVM (200 µg/kg). Clinical and laboratory assessments were performed at 4, 8, 24, 48, and 72 hours and 5, 7, 9, and 14 days posttreatment.

Results

Posttreatment adverse events were similar following DEC or IVM, but peaked earlier in subjects who received DEC, consistent with a trend toward more rapid and complete microfilarial clearance in the DEC group. After a transient rise (post-IVM) or fall (post-DEC) in the first 24 hours posttreatment, the eosinophil count rose significantly in both groups, peaking at day 5 in the DEC group and day 9 in the IVM group. Serum interleukin 5 levels and eosinophil activation, as assessed by surface expression of CD69 and serum levels of eosinophil granule proteins, were increased posttreatment in both groups.

Conclusions

Despite differences in eosinophil and lymphocyte counts during the first 24 hours posttreatment, the overall pattern of hematologic and immunologic changes suggest that posttreatment reactions following DEC and IVM share a common pathophysiology.

Clinical Trials Registration

NCT01593722.

Loiasis in US Traveler Returning from Bioko Island, Equatorial Guinea, 2016

The filarial parasite Loa loa overlaps geographically with Onchocera volvulus and Wuchereria bancrofti filariae in central Africa. Accurate information regarding this overlap is critical to elimination programs targeting O. volvulus and W. bancrofti. We describe a case of loiasis in a traveler returning from Bioko Island, Equatorial Guinea, a location heretofore unknown for L. loa transmission.

Efficacy, Safety, and Pharmacokinetics of Coadministered Diethylcarbamazine, Albendazole, and Ivermectin for Treatment of Bancroftian Filariasis

BACKGROUND

Available treatments for lymphatic filariasis (LF) are limited in their longterm clearance of microfilaria from the blood. The safety and efficacy of a single-dose triple-drug therapy of the antifilarial drugs diethylcarbamazine (DEC), ivermectin (IVM), and albendazole (ALB) for LF are unknown.

METHODS

We performed a pilot study to test the efficacy, safety, and pharmacokinetics of single-dose DEC, IVM, and ALB in Wuchereria bancrofti-infected Papua New Guineans. Adults were randomized into 2 treatment arms, DEC 6 mg/kg + ALB 400 mg (N = 12) or DEC 6 mg/kg + ALB 400 mg + IVM 200 μg/kg (N = 12), and monitored for microfilaria, parasite antigenemia, adverse events (AEs), and serum drug levels.

RESULTS

Triple-drug therapy induced >2-log reductions in microfilaria levels at 36 and 168 hours after treatment compared with approximately 1-log reduction with 2 drugs. All 12 individuals who received 3 drugs were microfilaria negative 1 year after treatment, whereas 11 of 12 individuals in the 2-drug regimen were microfilaria positive. In 6 participants followed 2 years after treatment, those who received 3 drugs remained microfilaria negative. AEs, particularly fever, myalgias, pruritus, and proteinuria/hematuria, occurred in 83% vs 50% of those receiving triple-drug compared to 2-drug treatment respectively (P = .021); all resolved within 7 days after treatment. No serious AEs were observed in either group. There was no significant effect of IVM on DEC or ALB drug levels.

CONCLUSIONS

Triple-drug therapy is safe and more effective than DEC + ALB for Bancroftian filariasis and has the potential to accelerate elimination of lymphatic filariasis.

CLINICAL TRIALS REGISTRATION

NCT01975441.

Drug-induced uveitis

INTRODUCTION

Drug-induced uveitis is a well described but often overlooked and/or misdiagnosed adverse reaction to medication. There are an increasing number of medications that have been related to the onset of intraocular inflammation. Identification of these inciting agents may decisively help the diagnostic algorithm involving new cases of uveitis.

AREAS COVERED

This review intends to be an updated comprehensive, practical guide for practitioners regarding the main drugs that have been associated with uveitis. A classification proposed by Naranjo et al. in 1981 for establishing potential causality is applied examining possible mechanisms of action. A guide for clinicians about the rationale of these observations when dealing with patients with uveitis is provided.

EXPERT OPINION

Several agents with different routes of administration (systemic, topical and/or intraocular) may cause intraocular inflammation. The mechanism behind ocular inflammation is frequently unknown. Clinicians should be aware of the potential drug effect to optimize diagnosis and management of such patients.

Mass drug administration coverage evaluation survey for lymphatic filariasis in bagalkot and gulbarga districts

Background:

Lymphatic filariasis (LF) is endemic in 83 countries and territories, with more than a billion people at risk of infection. In view with the global elimination, mass drug administration (MDA) with single dose of diethylcarbamazine and albendazole tablets was carried out for the eligible population in Bagalkot and Gulbarga districts.

Objective:

Assess coverage of MDA against LF in Bagalkot and Gulbarga districts.

Materials and Methods:

In this cross-sectional coverage evaluation survey, one urban and three rural clusters were selected randomly in each district. The data were collected in a pretested performa, computed and analyzed using SPSS-10 to calculate frequencies and proportions.

Results:

A total of eight clusters in two districts resulted in a total study population of 1,228 individuals. The overall compliance rate in Bagalkot district was 78.6% and in Gulbarga district it was only 38.8%. The prime reason for noncompliance was fear of side effects and not received tablets.

Conclusion:

There is an urgent need for more effective drug delivery strategies to improve the compliance in both the districts.

The Global Programme to Eliminate Lymphatic Filariasis: History and achievements with special reference to annual single-dose treatment with diethylcarbamazine in Samoa and Fiji

Diethylcarbamazine (DEC), first introduced in 1947, was shown to have strong efficacy and safety for treatment of human lymphatic filariasis, which is caused mostly by a species Wuchereria bancrofti. Many studies to optimize the dosage and treatment schedule of DEC followed, and, based on the results, control programs with various regimens were implemented in different endemic areas/countries. By the mid 1970s, with endorsement by the WHO Expert Committee on Filariasis (3rd report, 1974), the standard DEC regimen for W. bancrofti infection in mass treatment had been established in principle: a total dose of 72 mg/kg of body weight given in 12 divided doses, once weekly or monthly, at 6 mg/kg each. Not long after the committee report, the efficacy of annual single-dose treatment at 6 mg/kg, which is only one twelfth of the WHO-recommended dose in a year, was reported effective in French Polynesia (study period: 1973-78), and later in Samoa (study period: 1979-81). These results were published between 1978 and 1985 in the Bulletin of WHO but received little attention. In the mid 1980s, the efficacy of ivermectin, the first-choice drug for onchocerciasis, against lymphatic filariae came to light. Since the effect at a single dose was remarkable, and often better than DEC, it was predicted that the newly introduced drug would replace DEC. Treatment experiments with ivermectin increased quickly in number. Meanwhile, annual single-dose mass drug administration (MDA) with DEC at 6 mg/kg was under scrutiny in Samoa and Fiji. In the early 1990s, the Samoan study, which covered the entire population of 160,000 with 3 annual MDAs, reported a significant reduction in microfilaria (mf) prevalence and mean mf density, while in Fiji, the efficacy of 5 rounds of annual MDA (total dose, 30 mg/kg) was shown to be as effective as 28 multi-dose MDA spread over 2 years (6 weekly plus 22 monthly treatments at 5 mg/kg; total dose, 140 mg/kg). Several additional studies carried out in Samoa in relation to the annual single-dose MDAs revealed that low density mf carriers, who have a very low mf count of 1-20/ml of venous blood, could not play a significant role in filariasis transmission.From around 1990, studies on spaced low-dose DEC treatments and various types of combination chemotherapy with DEC and ivermectin increased. Albendazole, a well-known anti-intestinal helminths agent, was later added to the combination. The main findings of these studies with W. bancrofti are: (i) a single dose of DEC at 6 mg/kg reduced mean mf density by ca. 90% 1 year after treatment; (ii) the same dose could damage/kill adult worms; (iii) a single dose of ivermectin at ca. 400 µg/kg was more effective than DEC in reducing mf density during the first year and was similarly or less effective in the second year; (iv) ivermectin probably could not kill adult worms; (v) a single combined dose of albendazole (400 mg) and DEC (6 mg/kg) was effective to reduce mf density by 85 to nearly 100% 12-24 months after treatment; and (vi) ivermectin or albendazole included in the combination chemotherapy produced "beyond-filariasis" benefits: clearance/reduction of intestinal helminths, and, additionally, in the case of ivermectin, skin-dwelling ectoparasites.The Global Programme to Eliminate Lymphatic Filariasis (GPELF) started its worldwide activities in 2000, with the target of elimination by 2020. The basic strategy is to conduct annual single-dose MDAs for 4-6 years. In 2000-2007, a minimum of 570 million individuals were treated in 48 of 83 endemic countries. The drugs used are DEC 6 mg/kg plus albendazole 400 mg in most countries, or ivermectin 200-400 µg/kg plus albendazole 400 mg particularly in onchocerciasis endemic countries in Africa. (MDAs with DEC alone had been used in India.)The GPELF achieved impressive results in terms of parasitological cure/improvement, clinical benefits, social and economic impacts, etc. However, the most impressive result of all was the programme's success in mobilizing hundreds of millions of local people, who not only took drugs but many of them actively supported MDAs as drug distributors and volunteers. Beyond filariasis, the role people can play in supplementing rural health services is now a topic of discussion and a source of hope for a new sustainable system.

A Sensitive RP-HPLC Method for Simultaneous Estimation of Diethylcarbamazine and Levocetirizine in Tablet Formulation

A simple, sensitive and reproducible method was developed and validated for the simultaneous estimation of diethylcarbamazine and levocetirizine in its tablet formulation by reverse phase high performance liquid chromatography using Waters1515 HPLC with UV detector at the λ(max) of 224 nm, using Princeton Sphere-100 C(18) (250×4.6 mm. 5 μ) column. The mobile phase used was 20mM potassium dihydrogen orthophosphate buffer (pH: 3.2):acetonitrile (50:50 v/v) with isocratic flow (flow rate 1 ml/min) and the pH was adjusted with orthophosphoric acid. Losartan potassium was used as an internal standard. The compounds diethylcarbamazine, levocetirizine and losartan potassium were eluted at 2.12, 4.27 and 5.96 min, respectively. The peaks were eluted with better resolution. The method was accurate with assay values of 96.32 and 93.04% w/w, precise (%RSD) with intra-day 1.72 and 1.89 and inter-day 1.85 and 1.92, recoveries 102.86 and 101.1% w/w, which are very sensitive with limit of detections (LOD)'s 75, 50 ng/ml and limit of quantification (LOQ)'s 100, 75 ng/ml and linear with R(2) values 0.994 in the range of 5 to 30 μg/ml 0.1 to 1 μg/ml for diethylcarbamazine and levocetirizine, respectively. Hence this method can be applied for quantification of different formulations containing diethylcarbamazine and levocetirizine simultaneously.

Successful control of lymphatic filariasis in the Republic of Korea

A successful experience of lymphatic filariasis control in the Republic of Korea is briefly reviewed. Filariasis in the Republic of Korea was exclusively caused by infection with Brugia malayi. Over the past several decades from the 1950s to 2006, many investigators exerted their efforts to detection, treatment, and follow-up of filariasis patients in endemic areas, and to control filariasis. Mass, combined with selective, treatments with diethylcarbamazine to microfilaria positive persons had been made them free from microfilaremia and contributed to significant decrease of the microfilarial density in previously endemic areas. Significant decrease of microfilaria positive cases in an area influenced eventually to the endemicity of filariasis in the relevant locality. Together with remarkable economic growth followed by improvement of environmental and personal hygiene and living standards, the factors stated above have contributed to blocking the transmission cycle of B. malayi and led to disappearance of this mosquito-borne ancient disease in the Republic of Korea.

Effect of diethylcarbamazine on serum antibodies to feline infectious peritonitis in cats

In preceding studies by the author, use of the immunomodulator drug diethylcarbamazine resulted in the detection of antibodies to feline oncornavirus-associated cell membrane antigen in nine feline leukaemia virus infected cats that had previously given negative results to this antibody. In the present report, seven diethylcarbamazine-treated cats developed higher serum antibody titres to feline infectious peritonitis more frequently than did seven untreated controls. Since feline infectious peritonitis is caused by a coronavirus, these results suggest that diethylcarbamazine treatment could be exploited for vaccination and treatment strategies for non-retroviral in addition to retroviral infections.