Lymphatic Filariasis in East District, Sikkim.

East district of Sikkim has been considered as non-endemic for lymphatic filariasis (LF). However, a LF survey conducted during 2008 revealed microfilaria rate (mf rate) of 1.2%. The LF survey was carried out in 15 randomly selected villages and urban localities of East Sikkim. Out of 3,428 night blood smears collected and examined, 42 were found positive for Wuchereria bancrofti. Microfilaria (mf) carriers were detected from 5 surveyed villages and 5 urban localities of Singtam and Rangpoo with mf rate ranging from 0.5% to 4.2%. The mean mf density was 5.4 per 20cmm3 blood. All mf carriers were residents of east district, Sikkim except two persons who were from Bihar. The detection of microfilaria in young children who had never moved from the area indicates probable indigenous transmission. Out of 15 surveyed areas LF disease was found in 11 areas with prevalence ranging from 0.4% to 7.0%.(Disease rate was 1.6%) (1.7% for Males & 1.4% for females). One local individual was found with lymphoedema and also mf positive. Vector density ranged from 70 to 435 per ten-man-hours, sufficient for transmission of LF. 712 female Cx. quinquefasciatus were dissected to detect the filarial infection and none was found positive. The present survey findings indicate endemicity of filariasis in East district of Sikkim.

Status of Lymphatic Filariasis in Lucknow District, Uttar Pradesh.

Lucknow district was endemic for lymphatic filariasis (LF). During March 2008, LF survey was carried out in 14 randomly selected villages (six Primary Health Centres) and 4 Mohallas of Lucknow city. Out of 3,654 night blood smears (NBS) collected and examined, 209 were found positive for Wuchereria bancrofti (micrifilaria rate: 5.7%). Microfilaria (mf) carriers were detected from all surveyed villages and Mohallas. The age of these positive persons ranged from 6-70 years. In all areas, prevalence of microfilaraemia generally increased with age up to 21- 30 years. Males (6.7%) were more affected than females (3.9%). All mf carriers were residents of Lucknow district. Overall disease rate was 4.7%. In all, 175 individuals had disease manifestations of LF. Out of 108 males, 81 had hydrocele(75%). Disease rate was similar in males (4.7%) and females (4.8%). The mean mf density was 9.5 per 20 cmm blood, but no significant difference between males (9.4) and females (9.9). Vector density ranged from 150 to 810 per ten-man-hours. Infectivity and infection rates were 0.14%. The present survey indicates that filariasis is one of the major public health problems in surveyed areas.

Lymphatic filariasis in rural areas of Patna District, Bihar. A challenge ahead.

Patna district was endemic for lymphatic filariasis (LF). During November 2004, a lymphatic filariasis survey was carried out in seven randomly selected villages from four PHCs of Patna district. Of 1878 night blood smears (NBS) examined, 117 were found positive for W. bancrofti infection (mf rate 6.2%). Microfilaria carriers were detected from all surveyed villages. In all areas prevalence of microfilaria generally increased with age to maximum 15-34 years and then decline within most age-groups. More males (6.4%) were affected than the females (5.8%). All microfilaria (mf) carriers were residents of Patna district. Over all disease rate was 9.1%. Out of 171 diseased individuals, 121 persons were having hydrocele (6.4%). Disease rate was higher in males (12.0%) than females (4.1%). The mean mf density was 11.7. There was no significant difference of mean mf density in males and females. Vector density ranged from 205 to 780 per ten man hours. The survey indicates that the filariasis situation remained unchanged since last fifty years and still is one of the major public health problem in surveyed areas.

Lymphatic filariasis in Bilaspur district, Chhattisgarh.

As per earlier reports only Ratanpur PHC of the district Bilaspur of Chattisgarh was endemic for filariasis. During the present survey microfilaria infection and disease manifestations were detected in two more PHCs namely Bilha and Bilaspur. 3426 Night blood smears were collected from 24 randomly selected localities (13 rural and 11 urban) covering 25% known endemic areas and 75% reportedly non-endemic areas. Sample size was calculated taking 12% prevalence rate using standard statistical formula. Sixty-two indigenous residents (mf rate 1.80%) were found positive for W. bancrofti infection. Males (2.17%) were more affected than females (1.19%). The mf carriers were 2.05% in rural and 1.45% in urban communities, which indicates that lymphatic filariasis is prevalent in rural areas also. The mean mf density was 5.06. No infective or infected mosquitoes could be detected in Culex quinquefasciatus (544 nos.), M. annulifera (13 nos.) and M. uniformis (2 nos.). Comparing the earlier studies, in Bilaspur district the infection has been showing a declining trend and Brugia malayi infection has disappeared.

Bancroftian filariasis in Bagdogra town, district Darjeeling (West Bengal).

Filaria endemicity is probably gradually increasing over the years in Bagdogra town, district Darjeeling (West Bengal). Of 1511 night blood smears examined, 35 were found positive for Wuchereria bancrofti (mf rate 2.32%). The microfilaria (mf) rates for males and females were 2.84% and 1.79 % respectively. The age of these positives ranged from 5-45 years. The mf rate was highest (4.46%) in the age group of 20-29 years. All mf carriers were local residents of Bagdogra and Wuchereria bancrofti was only the infection encountered. Mean microfilaria density was 7.71 per 20 cmm. of blood, whereas Median microfilaria density (MFD50) was 21 per 20 cmm. of blood. Disease and filarial endemicity rates were 0.33% and 2.65% respectively. Ten man hour vector mosquito density ranged from 30 to 65. Out of 49 female Culex quinquefasciatus mosquitoes dissected for the presence of filaria infection, none was found positive for the infection. During 1976 survey in the same town, mf rate was 1.6% and disease rate was nil.