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An investigation of the disparity in estimates of microfilaraemia and antigenaemia in lymphatic filariasis surveys.

Cano J, Moraga P, Nikolay B, Rebollo MP, Okorie PN, Davies E, Njenga SM, Bockarie MJ, Brooker SJ - Trans. R. Soc. Trop. Med. Hyg. (2015)

Bottom Line: This paper presents the results of an extensive literature search for surveys that estimated both microfilaraemia and antigenaemia in order to better understand the disparity between the two measures.Regression analysis was unable to identify any predictable relationship between the two measures.The implications of findings for risk mapping and surveillance of LF are discussed.

View Article: PubMed Central - PubMed

Affiliation: Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, Keppel Street, London, UK jcano.ortega@lshtm.ac.uk.

No MeSH data available.


Related in: MedlinePlus

(A) The relationship between the prevalence of lymphatic filariasis based on microfilaraemia (pmf) and prevalence estimated from antigenemia (pICT), grouped by continent and pre- and post-control. (B) Observed and predicted relationship between pICT and pmf. For each pICT value, observed and predicted pmf values obtained from the model without random effects grouped by pre- and post-control. Details of included studies are shown in Supplementary Table 1.
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TRV048F1: (A) The relationship between the prevalence of lymphatic filariasis based on microfilaraemia (pmf) and prevalence estimated from antigenemia (pICT), grouped by continent and pre- and post-control. (B) Observed and predicted relationship between pICT and pmf. For each pICT value, observed and predicted pmf values obtained from the model without random effects grouped by pre- and post-control. Details of included studies are shown in Supplementary Table 1.

Mentions: Figure 1A presents the relationship between pmf and pICT, stratified by pre- and post-intervention settings and by continent, and shows that pICT consistently overestimates prevalence compared to pmf, especially in post-control settings. The correlation between pmf and pICT is positive, but not very strong (Spearman's correlation coefficient of 0.62 and 0.59 under pre- and post-intervention settings, respectively). Despite these correlations, we were unable to obtain a well-fitting regression model between pICT and pmf that would enable prediction of pmf from pICT (Figure 1B). DIC values for the fitted models were 1163 and 2960 with and without random effects, respectively, indicating that effects of unmeasured characteristics that affect all individuals surveyed contribute to the observed variability. We were unable to account for age group, as surveys typically targeted all age groups (n=229/264). Sensitivity analysis explored separate models for different volumes of blood examined (20 µl or 20–60 µl), but showed that overall model fit did not improve (see results in the Supplementary information).Figure 1.


An investigation of the disparity in estimates of microfilaraemia and antigenaemia in lymphatic filariasis surveys.

Cano J, Moraga P, Nikolay B, Rebollo MP, Okorie PN, Davies E, Njenga SM, Bockarie MJ, Brooker SJ - Trans. R. Soc. Trop. Med. Hyg. (2015)

(A) The relationship between the prevalence of lymphatic filariasis based on microfilaraemia (pmf) and prevalence estimated from antigenemia (pICT), grouped by continent and pre- and post-control. (B) Observed and predicted relationship between pICT and pmf. For each pICT value, observed and predicted pmf values obtained from the model without random effects grouped by pre- and post-control. Details of included studies are shown in Supplementary Table 1.
© Copyright Policy - creative-commons
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4542699&req=5

TRV048F1: (A) The relationship between the prevalence of lymphatic filariasis based on microfilaraemia (pmf) and prevalence estimated from antigenemia (pICT), grouped by continent and pre- and post-control. (B) Observed and predicted relationship between pICT and pmf. For each pICT value, observed and predicted pmf values obtained from the model without random effects grouped by pre- and post-control. Details of included studies are shown in Supplementary Table 1.
Mentions: Figure 1A presents the relationship between pmf and pICT, stratified by pre- and post-intervention settings and by continent, and shows that pICT consistently overestimates prevalence compared to pmf, especially in post-control settings. The correlation between pmf and pICT is positive, but not very strong (Spearman's correlation coefficient of 0.62 and 0.59 under pre- and post-intervention settings, respectively). Despite these correlations, we were unable to obtain a well-fitting regression model between pICT and pmf that would enable prediction of pmf from pICT (Figure 1B). DIC values for the fitted models were 1163 and 2960 with and without random effects, respectively, indicating that effects of unmeasured characteristics that affect all individuals surveyed contribute to the observed variability. We were unable to account for age group, as surveys typically targeted all age groups (n=229/264). Sensitivity analysis explored separate models for different volumes of blood examined (20 µl or 20–60 µl), but showed that overall model fit did not improve (see results in the Supplementary information).Figure 1.

Bottom Line: This paper presents the results of an extensive literature search for surveys that estimated both microfilaraemia and antigenaemia in order to better understand the disparity between the two measures.Regression analysis was unable to identify any predictable relationship between the two measures.The implications of findings for risk mapping and surveillance of LF are discussed.

View Article: PubMed Central - PubMed

Affiliation: Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, Keppel Street, London, UK jcano.ortega@lshtm.ac.uk.

No MeSH data available.


Related in: MedlinePlus