Unprogrammed Deworming in the Kibera Slum, Nairobi: Implications for Control of Soil-Transmitted Helminthiases

<div><p>Background</p><p>Programs for control of soil-transmitted helminth (STH) infections are increasingly evaluating national mass drug administration (MDA) interventions. However, “unprogrammed deworming” (receipt of deworming drugs outside of nationally-run STH control programs) occurs frequently. Failure to account for these activities may compromise evaluations of MDA effectiveness.</p><p>Methods</p><p>We used a cross-sectional study design to evaluate STH infection and unprogrammed deworming among infants (aged 6–11 months), preschool-aged children (PSAC, aged 1–4 years), and school-aged children (SAC, aged 5–14 years) in Kibera, Kenya, an informal settlement not currently receiving nationally-run MDA for STH. STH infection was assessed by triplicate Kato-Katz. We asked heads of households with randomly-selected children about past-year receipt and source(s) of deworming drugs. Local non-governmental organizations (NGOs) and school staff participating in school-based deworming were interviewed to collect information on drug coverage.</p><p>Results</p><p>Of 679 children (18 infants, 184 PSAC, and 477 SAC) evaluated, 377 (55%) reported receiving at least one unprogrammed deworming treatment during the past year. PSAC primarily received treatments from chemists (48.3%) or healthcare centers (37.7%); SAC most commonly received treatments at school (55.0%). Four NGOs reported past-year deworming activities at 47 of >150 schools attended by children in our study area. Past-year deworming was negatively associated with any-STH infection (34.8% vs 45.4%, p = 0.005). SAC whose most recent deworming medication was sourced from a chemist were more often infected with <i>Trichuris</i> (38.0%) than those who received their most recent treatment from a health center (17.3%) or school (23.1%) (p = 0.05).</p><p>Conclusion</p><p>Unprogrammed deworming was received by more than half of children in our study area, from multiple sources. Both individual-level treatment and unprogrammed preventive chemotherapy may serve an important public health function, particularly in the absence of programmed deworming; however, they may also lead to an overestimation of programmed MDA effectiveness. A standardized, validated tool is needed to assess unprogrammed deworming.</p></div

A diagnostic and epidemiologic investigation of acute febrile illness (AFI) in Kilombero, Tanzania

<div><p>Introduction</p><p>In low-resource settings, empiric case management of febrile illness is routine as a result of limited access to laboratory diagnostics. The use of comprehensive fever syndromic surveillance, with enhanced clinical microbiology, advanced diagnostics and more robust epidemiologic investigation, could enable healthcare providers to offer a differential diagnosis of fever syndrome and more appropriate care and treatment.</p><p>Methods</p><p>We conducted a year-long exploratory study of fever syndrome among patients ≥ 1 year if age, presenting to clinical settings with an axillary temperature of ≥37.5°C and symptomatic onset of ≤5 days. Blood and naso-pharyngeal/oral-pharyngeal (NP/OP) specimens were collected and analyzed, respectively, using AFI and respiratory TaqMan Array Cards (TAC) for multi-pathogen detection of 57 potential causative agents. Furthermore, we examined numerous epidemiologic correlates of febrile illness, and conducted demographic, clinical, and behavioral domain-specific multivariate regression to statistically establish associations with agent detection.</p><p>Results</p><p>From 15 September 2014–13 September 2015, 1007 febrile patients were enrolled, and 997 contributed an epidemiologic survey, including: 14% (n = 139) 1<5yrs, 19% (n = 186) 5-14yrs, and 67% (n = 672) ≥15yrs. AFI TAC and respiratory TAC were performed on 842 whole blood specimens and 385 NP/OP specimens, respectively. Of the 57 agents surveyed, <i>Plasmodium</i> was the most common agent detected. AFI TAC detected nucleic acid for one or more of seven microbial agents in 49% of AFI blood samples, including: <i>Plasmodium</i> (47%), <i>Leptospira</i> (3%), <i>Bartonella</i> (1%), <i>Salmonella enterica</i> (1%), <i>Coxiella burnetii</i> (1%), <i>Rickettsia</i> (1%), and West Nile virus (1%). Respiratory TAC detected nucleic acid for 24 different microbial agents, including 12 viruses and 12 bacteria. The most common agents detected among our surveyed population were: <i>Haemophilus influenzae</i> (67%), <i>Streptococcus pneumoniae</i> (55%), <i>Moraxella catarrhalis</i> (39%), <i>Staphylococcus aureus</i> (37%), <i>Pseudomonas aeruginosa</i> (36%), Human Rhinovirus (25%), influenza A (24%), <i>Klebsiella pneumoniae</i> (14%), Enterovirus (15%) and group A <i>Streptococcus</i> (12%). Our epidemiologic investigation demonstrated both age and symptomatic presentation to be associated with a number of detected agents, including, but not limited to, influenza A and <i>Plasmodium</i>. Linear regression of fully-adjusted mean cycle threshold (C_t) values for <i>Plasmodium</i> also identified statistically significant lower mean C_t values for older children (20.8), patients presenting with severe fever (21.1) and headache (21.5), as well as patients admitted for in-patient care and treatment (22.4).</p><p>Conclusions</p><p>This study is the first to employ two syndromic TaqMan Array Cards for the simultaneous survey of 57 different organisms to better characterize the type and prevalence of detected agents among febrile patients. Additionally, we provide an analysis of the association between adjusted mean C_t values for <i>Plasmodium</i> and key clinical and demographic variables, which may further inform clinical decision-making based upon intensity of infection, as observed across endemic settings of sub-Saharan Africa.</p></div

Frequency of detection of single and multiple organisms by the AFI TAC assay.

<p>Frequency of detection of single and multiple organisms by the AFI TAC assay.</p

Clinical characteristics of enrolled febrile pediatric and adult patients.

<p>Clinical characteristics of enrolled febrile pediatric and adult patients.</p

Detections of viral, bacterial and parasitic agents by acute febrile illness (AFI) and respiratory TAC.

<p>Detections of viral, bacterial and parasitic agents by acute febrile illness (AFI) and respiratory TAC.</p

Proportion of children in each age group whose parents reported that they had been dewormed at least once during the previous year, Kibera, Kenya, 2012.

<p>Numbers in parentheses represent denominators for each age group.</p

Frequency of detection of single and multiple organisms by the respiratory TAC assay.

<p>Frequency of detection of single and multiple organisms by the respiratory TAC assay.</p

Sources of drugs for the most recent deworming, overall and by child type, among children who were reported as taking deworming medications at least once during the past year, Kibera, Kenya, 2012.

<p>Sources of drugs for the most recent deworming, overall and by child type, among children who were reported as taking deworming medications at least once during the past year, Kibera, Kenya, 2012.</p

Statistically significant findings from domain-specific and combined multivariate regression model of prevalent agents detected.

<p>Statistically significant findings from domain-specific and combined multivariate regression model of prevalent agents detected.</p

Box plots of parasite load (C_t) by level of parasite intensity.

<p>Box plots of parasite load (C_t) by level of parasite intensity.</p