@article{Morbey_Elliot_Zambon_Pebody_Smith_2017, title={Interpreting specific and general respiratory indicators in syndromic surveillance}, volume={9}, url={https://ojphi.org/ojs/index.php/ojphi/article/view/7597}, DOI={10.5210/ojphi.v9i1.7597}, abstractNote={<div style="left: 90px; top: 320.758px; font-size: 14.1667px; font-family: sans-serif; transform: scaleX(1.08129);" data-canvas-width="63.778333333333336">Objective</div><div style="left: 105px; top: 335.709px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.01072);" data-canvas-width="381.20799999999997">To improve understanding of the relative burden of different</div><div style="left: 90px; top: 352.376px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.01914);" data-canvas-width="394.6436666666668">causative respiratory pathogens on respiratory syndromic indicators</div><div style="left: 90px; top: 369.043px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.00092);" data-canvas-width="345.09999999999997">monitored using syndromic surveillance systems in England.</div><div style="left: 90px; top: 400.758px; font-size: 14.1667px; font-family: sans-serif; transform: scaleX(1.11768);" data-canvas-width="82.63416666666666">Introduction</div><div style="left: 105px; top: 415.709px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.987259);" data-canvas-width="378.05450000000025">Public Health England (PHE) uses syndromic surveillance systems</div><div style="left: 90px; top: 432.376px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.03211);" data-canvas-width="394.3858333333335">to monitor for seasonal increases in respiratory illness. Respiratory</div><div style="left: 90px; top: 449.043px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.967883);" data-canvas-width="395.0091666666668">illnesses create a considerable burden on health care services and</div><div style="left: 90px; top: 465.709px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.02885);" data-canvas-width="394.4595000000001">therefore identifying the timing and intensity of peaks of activity is</div><div style="left: 90px; top: 482.376px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.981025);" data-canvas-width="393.09666666666624">important for public health decision-making. Furthermore, identifying</div><div style="left: 90px; top: 499.043px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.993576);" data-canvas-width="395.4596666666664">the incidence of specific respiratory pathogens circulating in the</div><div style="left: 90px; top: 515.709px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.01714);" data-canvas-width="396.5844999999998">community is essential for targeting public health interventions</div><div style="left: 90px; top: 532.376px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.02306);" data-canvas-width="394.56149999999985">e.g. vaccination. Syndromic surveillance can provide early warning</div><div style="left: 90px; top: 549.043px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.00559);" data-canvas-width="393.77383333333336">of increases, but cannot explicitly identify the pathogens responsible</div><div style="left: 90px; top: 565.709px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.00078);" data-canvas-width="105.03166666666665">for such increases.</div><div style="left: 105px; top: 582.376px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.95412);" data-canvas-width="379.6921666666664">PHE uses a range of general and specific respiratory syndromic</div><div style="left: 90px; top: 599.043px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.08586);" data-canvas-width="398.4204999999996">indicators in their syndromic surveillance systems, e.g. “all</div><div style="left: 90px; top: 615.709px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.06255);" data-canvas-width="397.6583333333334">respiratory disease”, “influenza-like illness”, “bronchitis” and</div><div style="left: 90px; top: 632.376px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.967913);" data-canvas-width="394.66633333333306">“cough”. Previous research has shown that “influenza-like illness”</div><div style="left: 90px; top: 649.043px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.991524);" data-canvas-width="344.7033333333335">is associated with influenza circulating in the community</div><div style="left: 434.795px; top: 649.417px; font-size: 8.5px; font-family: serif;">1</div><div style="left: 439.133px; top: 649.043px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.95042);" data-canvas-width="46.364666666666665">whilst</div><div style="left: 90px; top: 665.709px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.03535);" data-canvas-width="394.4">“cough” and “bronchitis” syndromic indicators in children under 5</div><div style="left: 90px; top: 682.376px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.987101);" data-canvas-width="295.66966666666667">are associated with respiratory syncytial virus (RSV)</div><div style="left: 385.542px; top: 682.751px; font-size: 8.5px; font-family: serif; transform: scaleX(0.972);" data-canvas-width="12.392999999999999">2, 3</div><div style="left: 397.926px; top: 682.376px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.985928);" data-canvas-width="85.102">. However, the</div><div style="left: 90px; top: 699.043px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.0076);" data-canvas-width="393.7539999999999">relative burden of other pathogens, e.g. rhinovirus and parainfluenza</div><div style="left: 90px; top: 715.709px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.959273);" data-canvas-width="394.75699999999995">is less well understood. We have sought to further understand the</div><div style="left: 90px; top: 732.376px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.984278);" data-canvas-width="393.1207499999999">relationship between specific pathogens and syndromic indicators and</div><div style="left: 90px; top: 749.043px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.01679);" data-canvas-width="394.1917499999999">to improve estimates of disease burden. Therefore, we modelled the</div><div style="left: 90px; top: 765.709px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.991026);" data-canvas-width="393.07399999999996">association between pathogen incidence, using laboratory reports and</div><div style="left: 90px; top: 782.376px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.00088);" data-canvas-width="271.87249999999983">health care presentations, using syndromic data.</div><div style="left: 90px; top: 814.091px; font-size: 14.1667px; font-family: sans-serif; transform: scaleX(1.07287);" data-canvas-width="58.23916666666666">Methods</div><div style="left: 105px; top: 829.043px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.968794);" data-canvas-width="377.9425833333333">We used positive laboratory reports for the following pathogens as a</div><div style="left: 90px; top: 845.709px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.985681);" data-canvas-width="393.00741666666664">proxy for community incidence in England: human metapneumovirus</div><div style="left: 90px; top: 862.376px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.01074);" data-canvas-width="317.6095833333333">(HMPV), RSV, coronavirus, influenza strains, invasive</div><div style="left: 407.596px; top: 862.376px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.00063);" data-canvas-width="75.94749999999999">haemophilus</div><div style="left: 90px; top: 879.043px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.07431);" data-canvas-width="62.48916666666667">influenzae</div><div style="left: 152.508px; top: 879.043px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.01705);" data-canvas-width="73.2275">, invasive</div><div style="left: 225.747px; top: 879.043px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.04054);" data-canvas-width="263.49999999999994">streptococcus pneumoniae, mycoplasma</div><div style="left: 90px; top: 895.709px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.00811);" data-canvas-width="69.76091666666666">pneumoniae</div><div style="left: 159.741px; top: 895.709px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.03244);" data-canvas-width="324.80625000000003">, parainfluenza and rhinovirus. Organisms were chosen</div><div style="left: 90px; top: 912.376px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.984222);" data-canvas-width="277.51791666666674">that were found to be important in previous work</div><div style="left: 367.538px; top: 912.751px; font-size: 8.5px; font-family: serif;">2</div><div style="left: 371.788px; top: 912.376px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.982781);" data-canvas-width="111.25083333333333">and were available</div><div style="left: 90px; top: 929.043px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.96988);" data-canvas-width="392.42941666666667">from routine laboratory testing. Syndromic data included consultations</div><div style="left: 90px; top: 945.709px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.0258);" data-canvas-width="394.4354166666667">with family doctors (called General Practitioners or GPs), calls to a</div><div style="left: 90px; top: 962.376px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.987516);" data-canvas-width="392.76800000000003">national telephone helpline “NHS 111” and attendances at emergency</div><div style="left: 90px; top: 979.043px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.00665);" data-canvas-width="396.1991666666666">departments (EDs). Associations between laboratory reports and</div><div style="left: 90px; top: 995.709px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.994717);" data-canvas-width="395.84783333333337">syndromic data were examined over four winter seasons (weeks</div><div style="left: 90px; top: 1012.38px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.971301);" data-canvas-width="392.8912499999999">40 to 20), between 2011 and 2015. Multiple linear regression was used</div><div style="left: 90px; top: 1029.04px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.959979);" data-canvas-width="394.9355000000002">to model correlations and to estimate the proportion of syndromic</div><div style="left: 90px; top: 1045.71px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.00419);" data-canvas-width="395.48516666666666">consultations associated with specific pathogens. Finally, burden</div><div style="left: 90px; top: 1062.38px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.953176);" data-canvas-width="394.93266666666665">estimates were used to infer the proportion of patients affected by</div><div style="left: 90px; top: 1079.04px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.995596);" data-canvas-width="390.0083333333332">specific pathogens that would be diagnosed with different symptoms.</div><div style="left: 90px; top: 1110.76px; font-size: 14.1667px; font-family: sans-serif; transform: scaleX(1.08488);" data-canvas-width="51.17">Results</div><div style="left: 105px; top: 1125.71px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.03865);" data-canvas-width="379.2983333333333">Influenza and RSV exhibited the greatest seasonal variation and</div><div style="left: 90px; top: 1142.38px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.00586);" data-canvas-width="396.34083333333325">were responsible for the strongest associated burden on general</div><div style="left: 90px; top: 1159.04px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.978655);" data-canvas-width="395.05025000000006">respiratory infections. However, associations were found with the</div><div style="left: 90px; top: 1175.71px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.955733);" data-canvas-width="208.25425">other pathogens and the burden of</div><div style="left: 298.241px; top: 1175.71px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.00823);" data-canvas-width="154.57816666666665">streptococcus pneumoniae</div><div style="left: 452.785px; top: 1175.71px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.889291);" data-canvas-width="32.19233333333332">was</div><div style="left: 90px; top: 1192.38px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.00067);" data-canvas-width="283.6733333333333">important in adult age groups (25 years and over).</div><div style="left: 525px; top: 319.043px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.970747);" data-canvas-width="380.28999999999985">The model estimates suggested that only a small proportion of</div><div style="left: 510px; top: 335.709px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.04001);" data-canvas-width="394.5813333333331">patients with influenza receive a specific diagnosis that is coded to</div><div style="left: 510px; top: 352.376px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.987963);" data-canvas-width="395.3661666666668">an “influenza-like illness” syndromic indicator, (6% for both GP</div><div style="left: 510px; top: 369.043px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.02945);" data-canvas-width="394.6904166666666">in-hours consultations and for emergency department attendances),</div><div style="left: 510px; top: 385.709px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.990115);" data-canvas-width="393.12500000000006">compared to a more general respiratory diagnosis. Also, patients with</div><div style="left: 510px; top: 402.376px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.04305);" data-canvas-width="394.65641666666653">influenza calling NHS 111 were more likely to receive a diagnosis</div><div style="left: 510px; top: 419.043px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.04017);" data-canvas-width="394.62383333333315">of fever or cough than cold/flu. Despite these findings, the specific</div><div style="left: 510px; top: 435.709px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.986078);" data-canvas-width="392.73825">syndromic indicators remained more sensitive to changes in influenza</div><div style="left: 510px; top: 452.376px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.00079);" data-canvas-width="211.26750000000007">incidence than the general indicators.</div><div style="left: 510px; top: 484.091px; font-size: 14.1667px; font-family: sans-serif; transform: scaleX(1.10336);" data-canvas-width="85.01416666666667">Conclusions</div><div style="left: 525px; top: 499.043px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.974046);" data-canvas-width="378.10833333333323">The majority of patients affected by a seasonal respiratory pathogen</div><div style="left: 510px; top: 515.709px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.02035);" data-canvas-width="394.332">are likely to receive a non-specific respiratory diagnosis. Therefore,</div><div style="left: 510px; top: 532.376px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.02273);" data-canvas-width="396.57883333333353">estimates of community burden using more specific syndromic</div><div style="left: 510px; top: 549.043px; font-size: 14.1667px; font-family: serif; transform: scaleX(0.95177);" data-canvas-width="394.52466666666646">indicators such as “influenza-like illness” are likely to be a severe</div><div style="left: 510px; top: 565.709px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.02447);" data-canvas-width="394.55866666666634">underestimate. However, these specific indicators remain important</div><div style="left: 510px; top: 582.376px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.02051);" data-canvas-width="394.4254999999999">for detecting changes in incidence and providing added intelligence</div><div style="left: 510px; top: 599.043px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.00087);" data-canvas-width="170.76500000000004">on likely causative pathogens.</div><div style="left: 525px; top: 615.709px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.03605);" data-canvas-width="382.1302499999999">Specific syndromic indicators were associated with multiple</div><div style="left: 510px; top: 632.376px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.02);" data-canvas-width="394.2299999999997">pathogens and we were unable to identify indicators that were good</div><div style="left: 510px; top: 649.043px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.00916);" data-canvas-width="393.5556666666667">markers for pathogens other than influenza or RSV. However, future</div><div style="left: 510px; top: 665.709px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.00718);" data-canvas-width="393.7582500000001">work focusing on differences between ages and the relative levels of</div><div style="left: 510px; top: 682.376px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.00299);" data-canvas-width="393.6392499999999">a range of pathogens may be able to provide estimates for the mix of</div><div style="left: 510px; top: 699.043px; font-size: 14.1667px; font-family: serif; transform: scaleX(1.00063);" data-canvas-width="278.1908333333332">pathogens present in the community in real-time.</div>}, number={1}, journal={Online Journal of Public Health Informatics}, author={Morbey, Roger and Elliot, Alex J. and Zambon, Maria and Pebody, Richard and Smith, Gillian E.}, year={2017}, month={May} }