An investigation on the diversity of mosquitocidal bacteria and its relationship with incidence of vector borne diseases.

Control of mosquitoes is the most important aspect of public health, as mosquitoes transmit many human diseases, including the fatal infection, Japanese encephalitis. This paper addresses the isolation of new mosquitocidal bacteria from soil samples in the Union Territory of Pondicherry, India, where, no clinical cases of vector borne infections have been reported. Bacterial isolates from soil samples were screened for potential mosquitocidal strains and bioassays against mosquito vectors (Culex quinquefasciatus, Anopheles stephensi and Aedes aegypti) were carried out. Genomic DNA of potential mosquitocidal isolates was amplified and species identification was carried out using BLASTn program (NCBI). Phylogenetic analysis of 16S rRNA sequences of mosquitocidal bacteria revealed seven potential isolates. SDS-PAGE results have shown that there was considerable difference in the protein profiles. Numerical analysis revealed 4 distinct groups at similarity level 25%. The relationship between VBDs and prevalence of soil mosquitocidal bacteria in the study sites has elicited considerable interest in the diversity of mosquitocidal bacteria and their application for mosquito borne diseases control.

Effect of domiciliary limb hygiene alone on lymphoedema volume and locomotor function in filarial lymphoedema patients in Puducherry, India.

Lymphoedema of extremities is a major clinical manifestation of lymphatic filariasis. Recurrent episodes of acute dermato-lymphangioadenitis (ADLA) in these patients lead to progression of the clinical condition. Studies have documented the effectiveness of regular limb hygiene in reduction in frequency and duration of ADLA. However, no data is available on the effectiveness of limb hygiene alone on reduction of lymphoedema volume and locomotor function of the affected extremities. A total of 93 consecutive patients visiting VCRC Filaria Clinic formed a cohort for the study. The limb hygiene kit was supplied monthly free of cost to the patients. Assessments of oedema volume, frequency and duration of ADLA and quantitative assessment of locomotor function were carried out at baseline and after 12 months of intervention. All the 93 patients completed the follow-up. A total of 82 (88%) patients practiced limb hygiene regularly. The practice was higher among patients with higher grades of lymphoedema. The mean frequency of ADLA reduced from pre-intervention level of 2.4 to 0.8 during 12-month period of intervention in grade I cases, from 3.4 to 1.2 in grade II and from 4.8 to 1.8 in grade III cases. The mean duration (in days) for each ADLA episode was reduced from 4 at the rpe-intervention level and 2.5 during the 12-months intervention period. Though 'limb hygiene' practiced in domiciliary settings is feasible. Regular practices resulted in reduction of frequency and duration of ADLA attacks. However, reduction in oedema volume or improvement the locomotor function was not observed during 12 month period.

Do the filarial lymphoedema patients''3 months recall' on acute dermato-lymphangio-adenitis (ADLA) correlate with streptococcal serology?

AIM: The aim of this study was to know the correlation of patients' 3 months recall on acute dermato-lymphangio-adenitis (ADLA) with anti-streptolysin O (ASO) serology and its application as a tool to know the burden of ADLA in the community. METHODS: Fifty-nine lymphoedema (LE) patients and 27 age matched controls were clinically assessed for LE and the occurrence of ADLA during the previous 3 months was obtained by recall. After obtaining the informed consent, 2 mL of venous blood sample was collected and ASO was quantified in Olympus AU400 auto-analyzer. RESULTS: When the results were computed as two groups, controls and LE patients with no reported ADLA and LE patients with reported ADLA (by 3 months recall), the ASO positivity and ASO titre was significantly higher in the later group (P < 0.05). When the results were computed as three groups, controls with no reported ADLA, LE patients with no reported ADLA and LE patients with reported ADLA, the ASO titre was significantly higher in LE patients reported ADLA (P < 0.05). CONCLUSION: As ASO was measured in post-infection phase, we relied on the ASO titre for making conclusion. Patients' 3 months recall on ADLA correlates with the ASO titre and therefore, it could be considered as a tool to measure the burden of ADLA in the community. Multicentre community-based studies are needed to ascertain the findings.

Sensitization potential and reactogenicity of varying doses of BCG plus killed Mycobacterium leprae: an extended study.

This study is an extension of a previous study on an antileprosy combination vaccine of BCG plus killed Mycobacterium leprae (KML) regarding its sensitization potential and reactogenicity. The study was extended to see if by reducing the dose of BCG in the combination vaccine the incidence of suppurative adenitis could be reduced without a significant reduction in the level of postvaccination skin-test responses. The study included 860 individuals, and three preparations of the combination vaccine [BCG 0.05 mg + 6 x 10(8) KML (I), BCG 0.05 mg + 5 x 10(7) KML (II), BCG 0.01 mg + 5 x 10(7) KML (III)] along with normal saline (i.v.) were used. Each individual received one of these four preparations by random allocation. They were also tested with Rees' M. leprae soluble antigen (MLSA) and lepromin A 12 weeks after vaccination. Reactions to the MLSA were measured after 48 hr; reactions to lepromin A after 48 hr and 3 weeks. The character and size of the local response at the vaccination site were recorded at the third, eighth, and 15th week postvaccination. The results of the study showed that by halving the dose of BCG in the combination vaccine BCG plus 6 x 10(8) KML a) the incidence of suppurative regional adenitis was reduced significantly, b) there was no significant change in the post-vaccination response at 12 weeks as measured by Rees' MLSA and lepromin A, and c) the evolution of the vaccination lesion was somewhat prolonged. This dose was found satisfactory for use in a comparative antileprosy vaccine trial in South India.