Analysis of LF-Antibody Responses Following MDA in Kenya
To determine the current status of LF using a combination of seroepidemiological tools to determine prevalence of circulating filarial antigen (CFA) and antifilarial antibodies.
Preliminary study findings:
- 2,976 individuals (age: 2 to 100 years) were tested for circulating filariail antigen using the immunochromatographic (ICT) test during daytime visits. Night-time blood samples to detect microfilariae (MF) were requested from those who tested positive via the ICT test.
- Out of the 38 persons found to be positive for LF infection by ICT test, 33 provided a night-time blood sample for examination of MF. Overall, nine individuals were found to be MF positive, with the highest prevalence in Ndau Island.
- The current study suggests that LF transmission may be absent in Taita-Taveta and Tana River counties in coastal Kenya and therefore transmission assessment surveys (TAS) should be considered with a view to stopping MDA. By contrast, evidence for ongoing transmission in Kwale, Kilifi and Lamu counties indicates the need for further MDA rounds in these counties.
- Additionally, the study demonstrated the feasibility of conducting integrated serosurveillance of several infectious diseases of public health interest, as well as levels of seroprotection against vaccine preventable diseases. The findings of the current study underscore the added value of using multiplex antibody measurements to guide and monitor LF elimination efforts.