FILARIASIS
(Diagnosis, Diagnostics, Immunodiagnosis,
Immunodiagnostics, Pathogenesis, Vaccines & Drugs)
ABSTRACTS
1242.
No Abstract
1243. No Abstract
1244. Thanomsub
BW. Chansiri K. Sarataphan N. Phantana S.Differential diagnosis of human lymphatic filariasis
using PCR-RFLP. Molecular & Cellular Probes. 14(1):41-6, 2000 Feb.
Abstract
Filariasis is still a public health problem in tropical countries.
The most common causative agents of human filariasis are Wuchereria bancrofti
and Brugia malayi. Traditional methods used to detect filarial parasites in
human, animal and vector populations are tedious, time consuming, and confer
little guarantee of sensitivity and species specificity. We have developed a
rapid and specific method to detect filarial parasite DNAs in blood and
mosquito samples using the polymerase chain reaction (PCR) technique. The
primers used are MF/F and MF/R which amplify a 1.5 kb glutathione peroxidase
gene of filarial worms. Using the restriction fragment length polymorphism
(RFLP) technique, these PCR products will be further digested with restriction
enzymes either Hpa I, Pst I, Alu I or
Hinf I to differentiate the genus of filaria. This PCR-RFLP technique
can be apply to use in diagnosis and to differentiate between species of
filaria in humans the reservoir host and the mosquito vector in endemic areas
Copyright 2000 Academic Press.
1668.
Esterre P. Plichart C. Huin-Blondey MO. Nguyen L. Role of streptococcal infection in the acute pathology
of lymphatic filariasis. Parasite.
7(2):91-4, 2000 Jun.
Abstract
Growing evidence suggest that secondary bacterial, mainly
streptococcal, infections contribute significantly to recurrent episodes of
acute adenolymphangitis (ADL) of
filarial origin. We examined the role of group A streptococci in the
progression of lymphedema in Polynesian patients with filariasis-related ADL
(22 cases) or chronic pathology (10 cases), or with erysipela (10 patients)
and, as controls, in 20 healthy adults.
Antistreptolysin O (ASLO) and anti-streptodornase B (ASDB) titers
were systematically determined in
parallel to parasitological and biochemical
tests. ASLO and ASDB assays were positive in 100% of erysipela, 75%
of filarial ADL as compared to 50% of
chronic pathology and 39% of healthy
controls. Interestingly, by opposition to ASLO titers which were not
significantly different between the four groups, ASDB titers were higher in ADL
(p = 0.019) and erysipela (p = 0.002) than in controls. These results support
the hypothesis that recurrent streptococcal infections may have an important
role in the pathogenesis of ADL in lymphatic filariasis.
1669. Fontes
G. Rocha EM. Brito AC. Fireman
FA. Antunes CM. The microfilarial
periodicity of Wuchereria bancrofti in north-eastern Brazil.Annals of Tropical Medicine & Parasitology. 94(4):373-9, 2000 Jun.
Abstract
The periodicity of Wuchereria bancrofti microfilariae (mff) in
peripheral blood was analysed in 42 microfilaraemics living in Maceio, in
Alagoas state, north-eastern Brazil. Nine blood samples were collected from
each subject, over a 24-h period, and two quantitative (60-microliter) thick
smears were prepared from each sample. Although all the subjects had detectable
microfilaraemias from 23.00 hours to 06.00 hours, no mff could be detected in
most (71.4%) of the smears prepared from samples collected at 15.00 hours.
Samples collected during the day, at 15.00 hours, contained 170 times fewer
mff/microliter than those collected at 01.00 hours, when microfilaraemias were
generally most intense. For diagnosis of bancroftian filariasis in Maceio,
blood samples should be collected
between 22.00 and 03.00 hours, when microfilarial counts will be at
least 90% of the peak counts. The
circadian variation observed was independent of the subject's gender and
microfilarial density. Mathematical analysis, using a simple harmonic-wave
model, indicated a periodicity index of 127.6 and that maximum microfilarial
densities occurred at 00.51 hours, confirming the nocturnal pattern of
microfilaraemia in the study area.
1670. Hoffmann
W. Petit G. Schulz-Key H. Taylor
D. Bain O. Le Goff L. Litomosoides
sigmodontis in mice: reappraisal of an old model for filarial research. [Review] [35 refs] Parasitology
Today. 16(9):387-9, 2000 Sep.
Abstract
Onchocerciasis and lymphatic filariasis (LF) are major causes of
severe morbidity and considerable
socio-economic problems throughout the tropics. Vector control and mass chemotherapy have helped to control
these infections in some regions, but
the temporary success of such measures argues strongly for the development of
vaccines. Success in such a venture will require detailed knowledge of protective
immune responses in conjunction with the identification of target antigens. By
comparison with other important parasitic infections, such as schistosomiasis
and leishmaniasis, work on the development of vaccines for onchocerciasis and
LF has been constrained because of the difficulties of producing cyclical and
patent filarial infection in laboratory mice. Wolfgang Hoffmann and colleagues
here outline the opportunities presented by the rodent filaria Litomosoides
sigmodontis for filarial research. [References: 35]
1671.Norman
RA. Chan MS. Srividya A. Pani SP. Ramaiah KD.
Vanamail P. Michael E. Das PK.
Bundy DA. EPIFIL: the development of an age-structured model for
describing the transmission dynamics and control of lymphatic filariasis.
Epidemiology & Infection.
124(3):529-41, 2000 Jun.
Abstract
Mathematical models of transmission dynamics of infectious
diseases provide a useful tool for investigating the impact of community based
control measures. Previously, we used a dynamic (constant force-of-infection)
model for lymphatic filariasis to describe observed patterns of infection and
disease in endemic communities. In this paper, we expand the model to examine
the effects of control options against filariasis by incorporating the impact
of age structure of the human community and by addressing explicitly the
dynamics of parasite transmission from
and to the vector population. This model is tested using data for Wuchereria bancrofti transmitted by
Culex quinquefasciatus in Pondicherry,
South India. The results show that chemotherapy has a larger short-term impact than vector control but
that the effects of vector control can
last beyond the treatment period. In addition we compare rates of recrudescence for drugs with different
macrofilaricidal effects.
1672.
Plaisier AP. Stolk WA.
van Oortmarssen GJ. Habbema JD.
Effectiveness of annual ivermectin treatment for Wuchereria bancrofti infection.
[Review] [19 refs] Parasitology Today.
16(7):298-302, 2000 Jul.
Abstract
Using estimates for the anthelmintic efficacy of a single dose of
ivermectin in the treatment of lymphatic filariasis patients, Anton Plaisier,
Wilma Stolk, Gerrit van Oortmarssen and Dik Habbema here present and discuss
model predictions of the impact of a five-year programme of annual community
treatment on the intensity of infection. They show that the effectiveness of such programmes in
terms of reductions in the microfilarial density depends critically on the
treatment coverage and the pattern of attendance at repeated mass administrations.
Improving these factors will possibly be more important than improving the
efficacy of ivermectin by increasing its dosage or by adding other drugs.
[References: 19]
1673. Ramzy RM.
Helmy H. el-Lethy AS. Kandil AM.
Ahmed ES. Weil GJ. Faris
R. Field evaluation of a
rapid-format kit for the diagnosis of bancroftian filariasis in Egypt. Eastern Mediterranean Health Journal. 5(5):880-7, 2000 Sep.
Abstract
The AMRAD-ICT Filariasis Test (ICT-Fil) is a new, rapid-format
card test for the detection of bancroftian antigenaemia in human blood. We
evaluated the performance of the test under field conditions in Egypt by
comparing 1813 endemic and 102 nonendemic participants. Endemic participants
were tested for microfilaraemia (thick smear and membrane filtration) and serum
antigenaemia (ELISA). The infection rates detected were 2.8% by thick smear,
3.5% by membrane filtration, 8.8% by ELISA and 9.0% by ICT-Fil. The card test
detected antigenaemia in 98.0% and 95.3% of microfilaraemia carriers testing
positive by thick smear and blood filtration respectively. Nonendemic
participants were ICT-Fil negative. Identical results were obtained for 173 out
of 184 (94%) endemic participants tested by the serum and whole blood ICT-Fil
versions.
2174. Esterre P. Plichart C. Sechan Y. Nguyen NL. The impact of 34 years of massive DEC chemotherapy on Wuchereria bancrofti infection and transmission: the Maupiti cohort. Tropical Medicine & International Health. 6(3):190-5, 2001 Mar.
Abstract
Semi-annual mass DEC chemotherapy combined with vector control at the beginning of the programme, has been administered on the remote island of Maupiti (French Polynesia) since 1955 (except two periods in 1960-67 and 1970-74). The results of two surveys in 1985 and 1989, reporting 0% microfilaraemia, led to the hope that the eradication of lymphatic filariasis had been achieved. We combined parasitological criteria (microfilaraemia by membrane filtration), immunological (antigenaemia and serum levels of specific IgG antibodies) and molecular (PCR-based evaluation of infection in mosquitoes) techniques and found only good control of the parasite: We found residual microfilaraemia in 0.4% of the sample (mean level in carriers: 101.2 mf/ml), antigenaemia in 4.6% (mean level in positive persons: 714.4 units/ml) and specific IgG in 21.6% (including in one very young child). In addition, an infection rate of 1.4% was calculated in the Aedes polynesiensis vector population. These data, obtained in 1997 just before a hurricane, were partially confirmed in 1999 (0.1% of infection rate in the vector). Together with the possibility of some resistance to DEC, various epidemiological factors critical for the eradication of lymphatic filariasis are discussed.
2175. Freedman DO. Plier DA. De Almeida AB. De Oliveira AL. Miranda J. Braga C. Effect of aggressive prolonged diethylcarbamazine therapy on circulating antigen levels in bancroftian filariasis. Tropical Medicine & International Health. 6(1):37-41, 2001 Jan.
Abstract
BACKGROUND: Single dose diethylcarbamazine (DEC) as used in control programmes is effectively microfilaricidal for periods of up to a year or more but has incomplete ability to kill Wuchereria bancrofti adult parasites. These regimens can be effective in breaking transmission by suppression of circulating microfilariae available to mosquito vectors. Whether prolonged or aggressive therapy with DEC has a significant effect on adult worms, which may live up to 12 years or more, and is important in the context of the treatment of individual patients, is still incompletely understood. METHODS: In order to investigate the adulticidal effect of aggressive therapy, DEC was given at 6 mg/kg/day for 12-day courses at 0, 6, 12, and 18 months and Og4C3 antigenaemia followed over two years in 38 CAg + Brazilians in a W. bancrofti endemic area. RESULTS: At two year follow-up, the median level of antigenaemia was 21% of the pre-treatment value. 92% of individuals had antigen levels < 50% of pretreatment values, but only 26% had completely cleared antigenaemia. The clearance rate at 24 months was only 12% (3/26) in the asymptomatic CAg + patients but 58% (7/12) in those with clinical manifestations of filariasis. The latter individuals cleared significantly more antigen (median of 0% pretreatment antigenaemia vs. 26%; P=0.02) than asymptomatic but infected individuals. CONCLUSION: Aggressive repeated therapy with DEC alone is ineffective in consistently eradicating adult W. bancrofti, especially in infected but asymptomatic individuals. Prolonged courses of combination therapy with other antifilarial drugs should be investigated for treatment of individual patients with the means to pursue aggressive personal medical care.
2176. Gyapong M. Gyapong JO. Owusu-Banahene G. Community-directed treatment: the way forward to eliminating lymphatic filariasis as a public-health problem in Ghana. Annals of Tropical Medicine & Parasitology. 95(1):77-86, 2001 Jan.
Abstract
The elimination of lymphatic filariasis as a public-health problem is currently dependent on the delivery of annual drug treatments to at least 80% of the eligible members of endemic populations for at least 5 years. However, for various reasons, this goal may not be achievable by the health systems of most endemic countries in sub-Saharan Africa, particularly if treatment is not community-directed. In Ghana, community-directed ivermectin treatment involving the regular public-health services at the implementation level (ComDT/HS) has recently been compared with mass-treatment in which only the health services participated (HST). Health staff and the target communities appreciated the ComDT/HS approach more than the HST approach and were more willing to participate in the community-directed scheme. The treatment coverage achieved by ComDT/HS (74.5%) was not only much higher than that of HST (43.5%) but also probably adequate for filariasis elimination. HST coverage was particularly poor in villages located > 5 km from a health facility, but distance from such a facility had no significant effect on treatment coverage in the ComDT/HS arm. As virtually all the subjects who received drugs swallowed them, compliance with treatment was not a problem. The ComDT/HS approach is therefore recommended, especially for areas where access to health facilities is poor and the health workers are over-stretched. The implications of these findings for the global programme for filariasis elimination are discussed.
2177. Jain S. Sodhani P. Gupta S. Sakhuja P. Kumar N. Cytomorphology of filariasis revisited. Expansion of the morphologic spectrum and coexistence with other lesions. Acta Cytologica. 45(2):186-91, 2001 Mar-Apr.
Abstract
OBJECTIVE: To review the cytomorphologic spectrum of the filarial worm and associated tissue response in 33 cases. STUDY DESIGN: Retrospective analysis was carried out in clinically unsuspected cases of filariasis diagnosed on cytology over a period of 10 years. Twenty-nine aspirate smears from 28 patients were air dried and stained with May-Grunwald-Giemsa stain. Four routine cervical smears and one centrifuged smear of urine were stained with Papanicolaou stain. RESULTS: Microfilariae alone and along with adult gravid females were present in 25 and 4 cases, respectively. In one case both adult male and female worms with microfilariae and eggs were seen. The diagnosis was based on the presence of eggs alone in one case and fragments of female worms in two. Four of these cases were neoplastic lesions, and microfilariae were found incidentally. In one case of splenomegaly microfilariae were seen along with Leishman-Donovan bodies. CONCLUSION: Filariasis can be diagnosed on cytology by demonstrating microfilariae, a male or female worm, or eggs alone. It can be seen in association with neoplastic lesions and rarely with other parasitic infections.
2735. Jain S.
Sodhani P. Gupta S. Sakhuja P.
Kumar N. Cytomorphology of filariasis revisited. Expansion of the
morphologic spectrum and coexistence with other lesions. Acta Cytologica. 45(2):186-91, 2001 Mar-Apr.
2736. Mohanty MC.
Satapathy AK. Sahoo PK. Ravindran B. Human bancroftian filariasis - a role for antibodies to parasite
carbohydrates. Clinical & Experimental Immunology. 124(1):54-61, 2001 Apr.
2737. Rathaur S.
Sharma S. Singh RN. Henkle K.
Selkirk ME. Antibody responses of Wuchereria bancrofti patients to
recombinant Brugia pahangi superoxide dismutase. Indian Journal of Experimental
Biology. 39(1):35-40, 2001 Jan.