Factors Influencing Drug Uptake during Mass Drug Administration for Control of Lymphatic Filariasis in Rural and Urban Tanzania

<div><p>Background</p><p>In most countries of Sub-Saharan Africa, control of lymphatic filariasis (LF) is based on annual mass drug administration (MDA) with a combination of ivermectin and albendazole. Treatment coverages are however often suboptimal for programmes to reach the goal of transmission interruption within reasonable time. The present study aimed to identify predictors and barriers to individual drug uptake during MDA implementation by the National LF Elimination Programme in Tanzania.</p><p>Methods</p><p>A questionnaire based cross sectional household survey was carried out in two rural and two urban districts in Lindi and Morogoro regions shortly after the 2011 MDA. 3279 adults (≥15 years) were interviewed about personal characteristics, socio-economic status, MDA drug uptake among themselves and their children, reasons for taking/not taking drugs, and participation in previous MDA activities for LF control.</p><p>Findings</p><p>The overall drug uptake rate was 55.1% (range of 44.5–75.6% between districts). There was no overall major difference between children (54.8%) and adults (55.2%) or between females (54.9%) and males (55.8%), but the role of these and other predictors varied to some extent between study sites. Major overall predictors of drug uptake among the interviewed adults were increasing age and history of previous drug uptake. Being absent from home during drug distribution was the main reason for not taking the drugs (50.2%) followed by clinical contraindications to treatment (10.8%), missing household visits of drug distributors (10.6%), and households not being informed about the distribution (9.0%).</p><p>Conclusion</p><p>Drug uptake relied more on easily modifiable provider-related factors than on individual perceptions and practices in the target population. Limited investments in appropriate timing, dissemination of accurate timing information to recipients and motivation of drug distributors to visit all households (repeatedly when residents are absent) are likely to have considerable potential for increasing drug uptake, in support of successful LF transmission elimination.</p></div

<i>Wuchereria bancrofti</i> microfilaraemia in Kirare village as seen during the pre-MDA survey in September 2004.

<p>*) of registered.</p><p>**) of examined.</p>#<p>) In mf/ml blood.</p

The effect of three rounds of mass drug administration (MDA) on <i>Wuchereria bancrofti</i> microfilaemia in Kirare village.

<p>Lines indicate microfilaria (mf) prevalence (•), mf geometric mean intensity (GMI) among all examined individuals (▪) and mf GMI among positive individuals only (▴). All indices are expressed in % of the baseline value. Vertical stippled lines indicate rounds of MDA.</p

Reasons given for not taking the drugs among the interviewed adult study populations from the four study sites in Lindi and Morogoro Region who reported not to have taken the drugs (n = 1403).

<p>Reasons given for not taking the drugs among the interviewed adult study populations from the four study sites in Lindi and Morogoro Region who reported not to have taken the drugs (n = 1403).</p

Mean monthly biting rate.

<p>(MBR; A), mean monthly transmission potential (MTP; B) and vector infection rate (C) in Kirare village during the pre-MDA period and the three post-MDA periods.</p

Circulating filarial antigen (CFA) and antibody to Bm14 in 90 volunteers from the mosquito collection houses in Kirare village.

<p>The individuals provided a serum specimen at the pre-MDA survey (September 2004)^# and were followed up at the four post-MDA surveys (January 2006, January 2007, October 2007 and October 2008).</p>#<p>) 55 females and 35 males; Age in 2004: 1–66 years (mean 24.1 years).</p><p>*) In CFA units.</p><p>**) In OD-values.</p

Map showing the location of the study sites in Lindi and Morogoro Region, Tanzania.

<p>Red  =  the two urban study districts; Green  =  the two rural study districts; Yellow  =  remaining parts of the two study regions; DSM  =  Dar es Salaam.</p

Vector mosquito catches from the 50 collection houses in Kirare village, and the results of dissections, during the pre-MDA period and the three post-MDA periods.

<p>*Nov-03 to Sep-04;</p><p>**Oct-04 to Jan-06;</p><p>***Feb-06 to Apr-07;</p><p>****May-07 to Oct-08.</p

Seasonal variation in monthly biting rate (MBR) and monthly transmission potential (MTP) in Kirare village during the study period (November 2003 to October 2008).

<p>MBR, panel A; MTP, panel B. Thick black line  =  all vector species combined; Thin green line  =  <i>Anopheles gambiae</i>; Thin red line  =  <i>An. funestus</i>; Thin blue line  =  <i>Culex quinquefasciatus</i>. Arrows indicate rounds of mass drug administration.</p

Characteristics of the interviewed adult study populations and their children from the four study sites in Lindi and Morogoro Region, and the reported drug uptake rates.

<p>Characteristics of the interviewed adult study populations and their children from the four study sites in Lindi and Morogoro Region, and the reported drug uptake rates.</p