Presence Of Microfilariae Research Articles

Adult filarial worm in the aspirate from a breast lump mimicking fibroadenosis

Filariasis is major public health hazard particularly in tropical countries like India. The presence of microfilaria using fine needle aspiration cytology has been reported from various sites. However, the presence of the adult gravid filarial worm with a surrounding host response has rarely been reported on breast aspirates. Here, we report a unique case in which aspiration cytology from a breast lump clinically suspicious of fibroadenosis of the breast, showed adult filarial worms with numerous microfilariae and a granulomatous inflammatory host response. The filarial worm appears to be ubiquitous in endemic areas, and the presence of an unexplained granulomatous lesion in breast should prompt a careful consideration of the filarial etiology in our country. Therapy with diethylcarbamazine, albendazole, and antibiotics are sufficient for treatment of this type of lesion.

Effect of Therapy by Using Advocate Spot-On Combination (Imidacloprid 10% and Moxidectin 2.5%) on Subcutaneous Dirofilariosis in Dogs

Dirofilaria (Nochtiella) repens is a filarioid parasite that causes subcutaneous dirofilariosis in dogs. Adults, while localized in subcutaneous tissues, lay embryos (microfilariae (mf)) into the blood stream of dogs, which constitute a reservoir for infection of other definitive or accidental hosts as humans. This study was carried out to assess the efficacy of spot-on combination of imidacloprid and moxidectin on microfilariaemia in naturally infected dogs. A group of 11 dogs was monthly examined for the presence of microfilariae in peripheral blood by modified Knott's test method. Treatment was administered monthly for 4 months. All dogs (i.e., 100%) became negative for microfilariaemia throughout the study. These results confirm the effect of the combination of imidacloprid and moxidectin on D. (Nochtiella) repens.

Effects of doxycycline on the endosymbiont Wolbachia in Dirofilaria immitis (Leidy, 1856)—Naturally infected dogs

Dirofilaria immitis carries intracellular endosymbiotic bacteria of the genus Wolbachia, known to be vital for the worms and sensitive to tetracycline antibiotics. With the purpose of studying the interaction between D. immitis and the endosymbiont Wolbachia sp., heartworm naturally infected microfilaremic or antigenemic dogs were treated with doxycycline (10 mg/kg/day of the drug in three cycles of 21 days each, with 6-month intervals). Blood samples were collected on days 0, 7 and 21 of each treatment as well as on day 111 after the beginning of each cycle. A final sample was collected on day 723 from the beginning of the first treatment. The samples were examined for the presence and number of microfilariae and the presence of antigen as well as the presences of D. immitis and Wolbachia sp. DNA using PCR (polymerase chain reaction). With this approach, an evaluation of the effect of doxycycline on antigenemia and on the presence of Wolbachia sp. DNA in dogs with heartworm infection was possible. Doxycycline treatment did not alter the detection of adult parasite antigens with the exception of two animals, though the number of animals carrying Wolbachia sp. DNA decreased, despite the presence of the microfilariae. The effect of the antibiotic therapy on the worms may have interfered with the transmission of heartworm disease because the population of microfilariae and the number of microfilaremic dogs were reduced and the microfilariae positive samples that were found did not test positive for Wolbachia sp. in many cases. These findings suggest that in areas were doxycycline is extensively used D. immitis transmission may be impaired by the reduction on the number of microfilariae and on the endosymbiotic bacteria in the larvae turning them incapable of completing development once they infected a new host.

Microfilaria concomitant with metastatic deposits of adenocarcinoma in lymph node fine needle aspiration cytology: A chance finding

Sir, Filariasis is a major health problem of the tropics and subtropics, commonly seen in countries like India, China, Indonesia, Africa, and the Far East. The disease is endemic all over India.[1] In India, Wuchereria bancrofti accounts for 90% of the total filarial infections.[2] Despite its high incidence, it is infrequent to find microfilariae in fine needle aspiration cytology (FNAC) smears and body fluids. Microfilariae have been observed as coincidental findings with other inflammatory conditions and neoplastic lesions.[3–6] Microfilariae at the site of the primary malignant tumor have been reported, but their coexistence with metastatic deposits have not been reported so far. We present here a rare case in which microfilariae were encountered in the fine needle aspiration of the supraclavicular lymph node along with secondary deposits from mucinous papillary adenocarcinoma. A 45-year-old male presented in the outpatient department with supraclavicular and cervical lymphadenopathy since 3 months. The left supraclavicular lymph node was of size 3cm×3cm and the left cervical lymph node was of size 2cm×2cm. The patient was referred to the pathology department for FNAC of the left supraclavicular lymph node. Microscopic examination showed highly cellular smears. Epithelial cells were seen arranged in groups, acinar pattern, and scattered singly. Cells were fairly uniform in size with round, hyperchromatic nuclei [Figure 1 lower inset]. Mucoid material was seen in the background. Along with these tumor cells, were noted sheathed microfilariae of W. bancrofti having multiple, coarse, discrete nuclei extending from the head to the tail, except in the small terminal portion of the caudal end [Figure 1 upper inset]. Based on the above findings, a diagnosis of metastatic deposits from adenocarcinoma with microfilariae of W. bancrofti was offered. The peripheral blood smear did not reveal any microfilariae. The patient was advised chest radiographs, which revealed a mass lesion in the upper lobe of the left lung. Figure 1 Fine-needle aspiration cytology of the lymph node showing tumor cells along with microfilaria (PAP ×40). Inset (upper) showing sheathed microfilaria with inflammatory cells. Inset (lower) showing tumor cells over a mucinous background (PAP, ×400) ... It is estimated that about 600 million people are living in areas endemic for lymphatic filariasis in the Southeast Asian region. There are about 60 million people infected in the region and about 31 million people have clinical manifestation of the disease.[1] Filariasis is a major public health problem in India. Heavily infected areas are found in Uttar Pradesh, Bihar, Jharkhand, Andhra Pradesh, Orissa, Tamilnadu, Kerala, and Gujarat. The disease manifestation ranges from none to both acute and chronic manifestations.[1] It is transmitted by the Culex mosquito and is caused by two closely related nematodes, W. bancrofti and Brugia malayi, which are responsible for 90% and 10% of the cases, respectively.[2] Infective larvae penetrate the feeding wound in the skin, enter the lymphatics and travel to the lymph nodes. After maturation in a few months, they develop into white, thread-like adult worms and survive for several (10–18) years in the lymph nodes. Once fertilized, the female discharges several thousand microfilariae (150–300-μ long), which dwell in the peripheral blood for 5–10 years.[2] Despite the high incidence of filariasis, microfilaria in FNAC is not a very common finding. There have been reports of single or small number of cases of microfilaremia at various sites such as lymph node, breast lump, bone marrow, bronchial aspirate, nipple secretions, pleural and pericardial fluid, ovarian cyst fluid, and cervicovaginal smears.[2] Microfilariae and adult filarial worms have occasionally been detected in association with neoplastic lesions in cytological smears. On searching the literature for microfilaria with malignant neoplasm, we have found some case reports describing coexistence of microfilaria with primary malignant tumor.[3–5] We have not found any case of microfilaria with secondary deposits. The presence of microfilariae along with neoplasms is generally regarded as a chance association.[5] In the present case, we feel that the presence of microfilaria in association with the metastatic deposits is an incidental finding and that the patient was harboring subclinical filariasis when the tumor metastasized. No microfilariae were detected in the peripheral smears. Our case illustrates the coexistence of microfilariae with secondary deposits of adenocarcinoma, which is a rare finding. This also highlights the importance of screening smears for parasites even in the absence of clinical symptoms, particularly in highly endemic areas.

Transplacental transfer of filarial antigens fromWuchereria bancrofti-infected mothers to their offspring

Maternal infection has been considered to be a risk factor for filarial infection in offspring. In order to examine the influence of maternal infection in neonates, we have determined the prevalence of circulating filarial antigen (CFA) and anti-filarial antibodies in 119 maternal and corresponding cord blood samples collected from an area endemic for bancroftian filariasis. Prevalence of antigenaemia was detected using Og4C3 circulating filarial antigen enzyme-linked immunosorbent assay. The presence of microfilariae was determined by filtration of a 1 ml sample through a Nuclepore membrane. Antibody isotypes (IgG, IgM, and IgE) to filarial antigen (Setaria digitata antigenic extract) were determined by enzyme linked immunosorbent assay (ELISA). Microfilariae were detected in 14 cases (11.8%), whereas the Og4C3 assay could detect filarial antigen in 44.5% of pregnant mothers. Interestingly, 24.5% of samples born from CFA-positive mothers were found positive for CFA. None of the cord samples from CFA-negative mothers were found positive for CFA. No significant difference was observed in prevalence of filarial-specific IgG, IgM and IgE antibodies in CFA-positive and negative mothers. IgG antibody was detected in 60.5% of maternal and 21.8% of cord samples. IgG antibody in the cord does not differ with the antigen status of the mother. In contrast IgM and IgE antibody prevalence was significantly higher in cord from infected mothers than non-infected mothers (11.3% vs 0 for IgM, 24.5% vs 3.03% for IgE). Our study demonstrates the transplacental transfer of circulating filarial antigen from mother to cord. Filaria-specific IgM and IgE antibodies were higher in cord blood from infected mothers than from non-infected mothers. The findings of the study provide additional circumstantial evidence for pre-natal sensitization to filarial antigens developed in utero.

Adult filarial worm in the tissue section of a breast lump.

Filariasis is a global health hazard. Incidence of filariasis is remarkably high in Indian sub continent. Apart from typical cases it is not common to find microfilaria and adult worm in tissue section and needle aspiration of the breast lump. Presence of microfilaria and adult worm in the breast is a rare finding. We report a case of filarial nodule in the breast of a 40 years old woman who presented with a pain less mass in the breast since last one month. It was diagnosed as fibroadenoma breast. Fine needle aspiration cytology showed mainly chronic inflammatory cells. The nodule was excised in toto and processed for histopathological examination. Histopathology confirmed the adult worm with granuloma in the breast nodule.

Filarial infection is resisted differentially by subjects having different blood group phenotypes

This study was aimed to elucidate the relationship between major blood group antigens (BGAs) and susceptibility or resistance to human lymphatic filariasis. A total of 492 human subjects, living in Raipur city of Chhattisgarh, endemic for bancroftian filariasis in Central India, were screened for the presence of Wuchereria bancrofti microfilariae and disease manifestations. The frequency of BGAs was tabulated as a function of the status of filariasis, namely normal (no infection), mf carrier (presence of microfilariae in blood), and elephantiasis (confirmed clinical manifestations). The comparison of ABO phenotype distributions among all the three groups clearly indicated that disease status has a significant relationship with the blood group attributes. The result of chi2 analysis of the frequencies of ABO phenotypes observed in microfilaraemic and elephantiasis groups (observed frequency vs. expected frequency computed based on the distribution of the normal population) revealed that there has been a significant alteration in the distribution of ABO phenotypes in microfilaraemic, but not in elephantiasis, group. The susceptibility to filarial infection was computed as a function of blood group phenotypes in the population. The susceptibility and conditional susceptibility for elephantiasis were the least among the subjects with AB phenotypes. The mechanism of association between filariasis and ABO antigens needs to be further explored to understand how the distribution of BGAs affects susceptibility/resistance to infection.

ALTERAÇÕES HISTOPATOLÓGICAS EM PULMÕES DE CÃES PORTADORES DE DIROFILARIOSE PULMONAR NO ESTADO DO RIO DE JANEIRO, BRASIL

The analysis, at light microscopy, of lungs histopathological alterations associated with the infection for Dirofilaria immitis in 33 (thirty three) dogs proceeding from Niteroi City, Rio de Janeiro, was carried out. A great diversity in number and intensity of lesions was observed. The most frequent pulmonary parenchyma changes had been interstitial pneumonia, interalveolar septa thickening and infartation, and the less had been focal fibrotic pleurisia and haemorrhage. Yet, in pulmonary artery and branches, the most frequent had been thrombosis and intimal proliferation to the lumen and the less had been pseudoaneurism and sclerosis. It was registered that in the presence of microfilariae in parenchyma, the infiltrates was predominantely formed for mononuclear cells, and in the destruction of the vessel wall, frequently for mixing or mononuclear cells. We concluded that more studies are necessary to the knowledge of the etiology and pathogenesis of Dirofilariasis, after recent studies that consider a bacterium endosymbionts of arthropods, Wolbachia, as the third variable, instead of the classic duality of host–parasite relationship. KEY WORDS: Dogs, Dirofilaria immitis, histopathological alterations, lungs, pulmonary artery.

Filarial infection induces protection against P. berghei liver stages in mice

Chronic helminth infections such as filariasis in human hosts can be life long, since parasites are equipped with a repertoire of immune evasion strategies. In many areas where helminths are prevalent, other infections such as malaria are co-endemic. It is still an ongoing debate, how one parasite alters immune responses against another. To dissect the relationships between two different parasites residing in the same host, we established a murine model of co-infection with the filarial nematode Litomosoides sigmodontis and the malaria parasite Plasmodium berghei (ANKA strain). We found that filarial infection of BALB/c mice leads to protection against a subsequent P. berghei sporozoite infection in one-third of co-infected mice, which did not develop blood-stage malaria. This finding did not correlate with adult worm loads, however it did correlate with the presence of microfilariae in blood. Interestingly, protection was abrogated in IL-10-deficient mice. Thus, murine filariasis, in particular when it is a patent infection, is able to modify the immunological balance to induce protection against an otherwise deadly Plasmodium infection and is therefore able to influence the course of malaria in favour of the host.

Microfilariae of the Filarial NematodeLitomosoides sigmodontisExacerbate the Course of Lipopolysaccharide-Induced Sepsis in Mice

Helminths facilitate their own survival by actively modulating the immune systems of their hosts. We investigated the impacts that different life cycle stages of the rodent filaria Litomosoides sigmodontis have on the inflammatory responses of mice injected with sublethal doses of lipopolysaccharide (LPS). Mice infected with female adult worms from prepatent infections, worms which have not yet started to release microfilariae, developed lower levels of proinflammatory cytokines in the peripheral blood after LPS challenge than sham-treated controls, demonstrating that female adult worms can mitigate the innate immune response. The presence of microfilariae in mice, however, through either direct injection or implantation of microfilaria-releasing adult female worms, turned the LPS challenge fatal. This lethal outcome was characterized by increased plasma levels of gamma interferon (IFN-gamma), tumor necrosis factor alpha (TNF-alpha), interleukin 12 (IL-12), and IL-6, greater numbers of macrophages and granulocytes in the peripheral blood, and decreased body temperatures in microfilaria-infected mice. Microfilaria-infected mice deficient in IFN-gamma receptor and TNF receptor 1 had increased survival rates after LPS challenge compared to immune-competent mice, suggesting that microfilariae worsen LPS-induced sepsis through actions of IFN-gamma and TNF-alpha. In summary, we have demonstrated that infection of mice with L. sigmodontis female adult worms from prepatent infections protects mice injected with LPS whereas microfilariae worsen LPS-induced sepsis through the induction of proinflammatory cytokines and upregulation of granulocytes, NK cells, and monocytes in the peripheral blood.

Microfilaria in thyroid gland nodule

Presence of microfilaria in the thyroid gland is a rare finding. Filariasis is a common public health problem in the Indian sub-continent. Most of the cases of microfilaria in thyroid gland reported in the literature are associated with goiter and thyroid neoplasms. Here, we present a rare case that showed microfilaria on fine needle aspiration cytology of solitary thyroid nodule.

Microfilariae in thyroid aspiration smear—An unexpected finding

Lymphatic filariasis is a major health problem in tropical countries including India. Despite its high incidence it is difficult to find microfilariae in blood and fine-needle aspirates due to the nocturnal periodicity of species endemic in India. Lymphatic filariasis can manifest as asymptomatic microfilaremia, hydrocele, lymphangitis, and lymphadenitis. The presence of microfilariae in thyroid aspirates is a rare finding. A case of microfilariae in a thyroid aspirate is being reported to emphasize the significance of careful screening of smears in endemic areas.

Prevalence of Setaria equine microfilaraemia in horses in Hungary

Peripheral blood samples were collected randomly from 195 horses in various parts of Hungary, and the presence of microfilariae was evaluated by the Knott technique. On the basis of morphological identification 18 of the horses (9.2 per cent) were infected with Setaria equina, and the infection was confirmed in 10 animals by pcr and sequencing. The level of microfilaraemia was between 1 and 1138 larvae in 2 ml of blood. There was no correlation between the time of sampling or the sex of the animals (stallions versus mares) and the prevalence of infection, but the prevalence decreased with age. There was a significant association between the prevalence of microfilaraemia and the presence of still waters; positive samples were collected either in the region of Lake Balaton, the largest lake in the country, or at places with nearby ponds.

Microfilaruria caused by canine dirofilariasis (Dirofilaria immitis): an unusual clinical presence

A 6-year-old, 18.2-kg, male mixed-breed dog was presented to Chulalongkorn Veterinary Teaching Hospital with clinical signs of hyperpnea, respiratory distress, vomiting, and anorexia. Blood and urine samples were collected for routine analysis. Microfilaremic examination and adult heartworm antigen test were conducted. Thoracic radiography was also performed. The clinical hematological and biochemical results demonstrated typical features of heartworm-infected dogs, including leukocytosis, thrombocytopenia, increases in alkaline phosphatase, alanine aminotransferase, and azotemia. Radiography showed typical findings of heartworm disease. Urinalysis revealed hematuria, pyuria, bacteriuria, hemoglobinuria, and proteinuria indicating lower urinary tract infection. Microfilaruria was detected in the urine sediment. They were identified morphologically as microfilariae of Dirofilaria immitis. The presence of microfilariae in the urine has not previously been described as a specific manifestation in dogs with dirofilariasis. The main objective of this article was to report new pathological findings in an extremely rare case of canine heartworm infection. However, its occurrence is presumably related to the inflammation or hemorrhage of the lower urinary tract and/or glomerulonephritis in this individual dog.

CD4+, CD8+, immunoglobulin status and ocular lesions among some onchocerciasis-infected rural Nigerians

CD4(+), CD8(+), immunoglobulin status and ocular lesions of some onchocerciasis-infected rural Nigerians as manifested by the presence of microfilariae in their skin snips and some chronic symptoms of the parasitic infestation were evaluated. The highest mean CD4(+) and mean microfilarial (mff) load of 560 +/- 20.46 unit cells/microl and 20 mff/mg were recorded among the individuals within the second decade of life, while the least mean CD4+ and mff load of 307.20 +/- 11.23 unit cell/microl and 6.5 mff/mg occurred among volunteers after 60 years of age. The highest mean CD8(+) of 388.00 +/- 23.71 unit cells/microl occurred at the third decade of life. The individuals above 60 years had the least mean CD8(+) of 350.25 +/- 11.90 unit cells/microl. The volunteers had mean CD4(+) of 372.45 +/- 109.02 unit cells/microl and mean CD8(+) of 359.42 +/- with an overall CD4(+):CD8(+) ratio of 1.04. The mean CD4(+) and mean CD8(+) had positive correlation with the mean microfilarial load (r = 0.52 and r = 0.40), respectively. The mean IgE, IgG, lgA, IgM, and IgD were 2,074.82 +/- 823.09, 19.36 +/- 2.49, 3.88 +/- 0.26, 3.59 +/- 0.38, and 0.29 +/- 0.19 mg/dl, and these immunoglobulins negatively correlated with the mean microfilarial load at r = -0.02, r = -0.15, r = -0.82, r = -0.37, and r = 0.26, respectively. Among these immunoglobulins evaluated, only mean IgE (2,074.82 +/- 823 ng/ml) was statistically different from the control subjects (0 mg/dl) at t = 3.39, P < 0.05. In all, the prevalence of the visual impairment and lesions were low. Among the six visual lesions, namely, cataract, choroidoretinitis, iridocyclitis, glaucoma, sclerosing keratitis, and optic atrophy encountered in Egoro-Eguare, only optic atrophy and sclerosing keratitis was reported among the children. The female adults had the highest prevalence of reduced vision 20(43.5%). Also, the prevalence of choroidoretinitis (2.2%) and iridocyclitis (2.2%) were the least prevalent ocular lesions reported among these female adults. The depletion of the CD4(+) contributed to the low prevalence of visual impairment and lesions in this locality. The depleted CD4(+), CD8(+), and the lower values of IgA, IgM, and IgG contributed in the maintenance of chronicity of onchocerciasis in Egoro-Eguare, Nigeria.

The first report of authochthonous dirofilariosis in dogs in the Czech Republic

Abstract In the Czech Republic, canine dirofilarial infection (Dirofilaria immitis and D. repens) is usually diagnosed in dogs coming from endemic areas and as such has been considered an imported infection. Here, 77 dogs that had never travelled abroad from the Břeclav area, close to Slovak border, were tested for Dirofilaria spp. infection. The presence of microfilaria in peripheral blood was detected by Knott test. Microfilariae were further examined by acid phosphatase staining and molecular methods (PCR). The presence of adult female D. immitis circulating antigens in blood was assessed by a commercial kit (PetChek, IDEXX Laboratories, Portland, USA). Microfilariae were detected in 7 (9 %) out of the 77 animals by the Knott test. The result of the acid phosphatase staining and PCR for all seven samples agreed with Dirofilaria repens species. Other five dogs of the 77 sera (6.5 %) sampled were serologically positive for circulating D. immitis antigens. No D. immitis microfilariae were found in these five dogs. D. repens positive dogs were negative on the ELISA for D. immitis. This is the first report of autochthonous cases of heart-worm disease and subcutaneous dirofilariosis in dogs in the Czech Republic.

Wuchereria bancrofti: Effect of single and multiple larval inoculations on infection dynamics and development of clinical manifestations in non-human primate Presbytis entellus

We earlier reported the successful experimental transmission of Wuchereria bancrofti from humans to the Indian leaf monkey ( Presbytis entellus) [Misra, S., Tyagi, K., Chatterjee, R.K., 1997. Experimental transmission of nocturnally periodic Wuchereria bancrofti to Indian leaf monkey ( Presbytis entellus). Experimental Parasitology 86,155–157.; Dube, A., Murthy, P.K., Puri, S.K., Misra-Bhattacharya, S., 2004. Presbytis entellus: a primate model for parasitic disease research. Trends in Parasitology 20(8), 358–360.] using a small number of animals. The present study, involving 27 langur monkeys, found the development of pathological manifestations ranging from filarial fever, lymphangitis, lymphadenitis, hydrocoele, and limb edema to minor histopathological changes in tissues after single, double, triple, or multiple inoculations of infective larvae of W. bancrofti recovered from Culex quinquefasciatus fed on human microfilaraemic blood. Thirty-eight percent of the infected langurs developed detectable microfilaraemia in their blood. Single or double larval exposure resulted in better worm establishment than multiple exposures with small numbers of larvae. All of the langurs receiving a single large inoculum and 85.71% of those receiving two inoculations harbored adult parasites. Worm establishment decreased with increasing number of larval inoculations. In all, 60% of infected langurs developed classical gross-pathological symptoms of lymphatic filariasis. Of these, 29.16% developed thickening of the lymphatics, 25% suffered from periodic rise in rectal temperature, and 16.66% developed scrotal swelling with presence of microfilariae in the hydrocoele fluid. Only one out of 25 langurs (4%) developed acute limb edema. It appeared that a single inoculum of a large number of infective larvae was able to induce maximum pathology. Fifty-six percent of the infected langurs acquired a peculiar sitting posture, retracting both the hind limbs, usually after 4–5 months of larval inoculation and eventually resulting in reduced mobility. Oral administration of diethylcarbamazine (citrate) at 12 mg/kg for 12 consecutive days to one langur caused 80% suppression in microfilaraemia on day 8, killing all the adult parasites. Of the two immunosuppressed (cortisone- or prednisolone-treated) male rhesus monkeys included in the study, neither developed any of the above lymphatic symptoms or parasites after receiving larval inoculations on two or three occasions; however, a rise in rectal temperature in one of the animals was noticed. The present study thus reveals that the Indian leaf monkey, P. entellus, may serve as an ideal non-human primate model of human bancroftian filariasis for carrying out longitudinal studies on pathology, host–parasite interactions, and preclinical evaluation of candidate anti-filarial drugs or vaccines.

Clinical manifestations of Onchocerciasis and some aspects of its control in Achi, Oji River Local Government Area, Enugu State, Nigeria

The clinical manifestations of Onchocerciasis are studied to highlight both the prevalence and the nature of morbidity of the disease in Achi, Oji River Local Government Area, Enugu State, Nigeria, and to comment on the control measures currently going on in the area. The main purpose is to contribute effectively to the incumbent work covered in the whole of Nigeria on Onchocerciasis with the view of discussing the medical and socio-economic importance of the disease and its vector in human populations, in the endemic areas. Parasitological examination by skin-snipping the local populace was carried out form ward to ward to establish the disease by the presence of microfilariae of O.volvulus . Also used to establish the disease was the palpating for nodules and the presence of other clinical manifestations. Ocular examination was carried out to determine ocular Onchocerciasis by impairment of visions, partial and total blindness. Visual acuity testing was carried out by employment of Snellen's Chart. Out of 10,000 subjects clinically examined, the result of 3,000 subjects were analysed as following: a total of 2,040 (68%) had onchocerciasis (clinically), 1,530 (75%) were adults, 510 (25%) were children. Of these 504 (24.7%) had onchodermatitis, 230 (45.7%) of whom were males and 274 (54.3%) were females; 167 (33.2%) were children and 337 (66.8%) were adults. Also 904 (44.3%) subjects had nodules, 367 (18%) had lizard skin, 408 (20%) had tigroid/leopard skin 8 (0.4%) had lymphadenopathies, 265 (62.3%) patients out of 426 for ocular examination had ocular lesions, while 5 (1.1%) were blind. The above results show Achi as hyperendemic. The clinical manifestations contribute immensely to the medical status, psyco-economic importance of the disease such as: marriage stigma, lower social and economic status, psycho-socio behavioural influence, confinement and immobilization of the patient, unproductive and incapacitated life and uncontrollable itching embarrassment. The productivity is lowered also by the biting menace of the vectors. The patient suffers loss in working days, the quality of life is reduced; in females, pregnancies could be affected and could be fatal. The above encounters are common in most endemic areas. Nigerian Journal of Parasitology Vol. 25, 2004: 101-106

Characterisation of a heparan sulfate proteoglycan homologue OvPG-1 from &lt;i&gt;Onochocerca volvulus&lt;/i&gt;

To determine the role of an immunodominant antigen OvPG-1 in human onchocerciasis. Cross-sectional study of subjects living in three onchocerciasis endemic areas. Mbonge and Tubah divisions of Western Cameroon and in Esmeralda Province of Ecuador. There were 94 and 99 subjects from the Cameroon rain forest and savannah respectively, and 83 endemic residents from Ecuador. The IgG2 anti-OvPG-1 responses of visually impaired and microfiladermic patients were significantly higher than for their age and sex matched counterparts with normal vision and no microfiladermia (p=0.024). Furthermore, the isotype specificity of anti-OvPG-I responses varied for the various onchocerciasis endemic zones. IgG1, IgG2, IgG3 and IgE levels correlated with the presence of microfilariae in Cameroon, but not in Ecuador. Increased IgG and IgE levels to the antigen OvPG-1 seem to correlate with the development of onchocercal eye pathology. The present results suggest that the OvPG1 is a dominant antigen of Onchocerca volvulus with a significant role in the pathogenesis of onchocerciasis.

Rhythmic Behaviour of W. Bancrofti Microfilaraemia in Human Population at Raipur

The temporal dynamics of microfilariae (mf) in human blood, and the biting activity and mf density in the vector were studied. Finger-prick blood samples (in duplicate) were collected from 14 microfilaraemic subjects at two-hourly intervals over a single 24-hour timescale. Samples were taken from 39 subjects at 22:00 in the first week of every month for a period of 17 consecutive months. The blood slides were dried, stained and examined for presence of microfilariae. Data were analyzed with cosinor rhythmometry. A statistically validated circadian rhythm was detected in mf density in 86% of the microfilaraemic subjects. For the circannual rhythm, the peak timing for microfilariae density was recorded in July, although the spread of the peak between subjects was quite wide, extending between May 17 and September 07. In a separate study, temporal variations in biting activity, mf density in the vector and in human blood were studied. The dynamics of parasite transmission were found to be sequential, with the peaks in the circadian rhythms appearing in the order: mf in human blood, biting activity and mf density in the vector. The biting periodicity appeared to be much more stable in all subjects; the peak appeared at 02:37 with a range between 00:39 and 03:22. The peak in mf frequency was earlier by 3 hours and 25 minutes, whereas the peak in mf frequency in the vector was later by about 2 hours 4 minutes. The observed synchronization between the rhythms of vector and host appears to be essential for effective transmission of diseases. Therefore, the application of chronobiologic principles may have a bearing in the success and failure of any future strategies aimed at the prevention, cure and management of filariasis.