Detecting, reporting, and analysis of priority diseases for routine public health surveillance in Liberia

An essential component of a public health surveillance system is its ability to detect priority diseases which fall within the mandate of public health officials at all levels. Early detection, reporting and response to public health events help to reduce the burden of mortality and morbidity on communities. Analysis of reliable surveillance data provides relevant information which can enable implementation of timely and appropriate public health interventions. To ensure that a resilient system is in place, the World Health Organization (WHO) has provided guidelines for detection, reporting and response to public health events in the Integrated Disease Surveillance and Response (IDSR) strategy. This case study provides training on detection, reporting and analysis of priority diseases for routine public health surveillance in Liberia and highlights potential errors and challenges which can hinder effective surveillance. Table-top exercises and group discussion lead participants through a simulated verification and analyses of summary case reports in the role of the District Surveillance Officer. This case study is intended for public health training in a classroom setting and can be accomplished within 2 hours 30 minutes. The target audience include residents in Frontline Epidemiology Training Programs (FETP-Frontline), Field Epidemiology and Laboratory Training Programs (FELTPs), and others who are interested in this topic.


Introduction
Liberia adopted the revised 2012 Integrated Disease Surveillance and Response (IDSR) guidelines based on lessons learned from the 2014 Ebola outbreak [1][2][3]. The national IDSR guidelines listed priority diseases reportable in Liberia, including diseases targeted as a potential public health emergency of international concern under the International Health Regulations (IHR [2005]) [1,3,4].
As part of implementation, the Ministry of Health (MoH) conducted a workshop to train the county health teams (CHTs) from each of the 15 counties in Liberia to conduct surveillance of priority diseases. Training was based on core functions of public health surveillance outlined in the IDSR (identify, report, analyse and interpret, and investigate and confirm), each with dedicated activities defined at every level of health administration (Appendix 1) [1].
After IDSR training, the MoH provided the CHTs with the necessary logistics to enable them to successfully implement and roll out IDSR at the district, health facility, and community levels. Question 1. Identify steps needed to implement 1) case identification and 2) reporting for IDSR at the district, health facility, and community level.
Detecting, Reporting, and Analysis of Priority Diseases for Routine Public Health Surveillance in Liberia Participant's Guide Version 1.0 4 Do not duplicate or distribute without written permission from the African Field Epidemiology Network Question 2. Draw a flow chart to illustrate the flow of data and process of case reporting for priority diseases from the community to national level according to national IDSR guidelines (Appendix 1). Clearly list the responsible role or organization for each step in the flow chart.

Part 1
Three weeks after the roll out of IDSR, the district surveillance officer for District A received a report of suspected cases of measles in his district through the community event-based surveillance system. However, out of three health facilities located in District A, Facilities A and B submitted reports with no counts of priority disease cases (including measles), while Facility C submitted no report for the same week. An investigation team was dispatched to verify the reported cases and assess the three health facilities.
Continued on next page à On arrival in the community, the team confirmed that the cases reported by community informants met the standard case definition for suspected measles. Additional cases were identified through active case finding by going from house to house, and to nearby communities. A master line list was shared with the County Health Officer. Samples were collected and transported to the reference laboratory for confirmation.
Next, the team visited the three health facilities to assess surveillance activities. On reviewing the medical records at Facility A, the DSO noticed some cases which met the standard case definition for suspected measles but were not reported. The surveillance focal person at this health facility indicated that they were not able to collect specimens from the suspected cases, which was why they did not report. Further review of medical records showed that suspected cases of other priority diseases were not reported over the past weeks for the same reason.
At Facility B, none of the staff trained in IDSR was present. The facility was under the management of the laboratory aid, nurse aid, administrator, and pharmacist who were unfamiliar with IDSR guidelines. The IDSR guidelines were not readily available in the facility to serve as reference. Review of their medical records showed that some cases met the case definitions but were not diagnosed or reported as priority diseases. Review of medical records at Facility C, which did not submit any report for the week, showed that none of the patients met the case definition for a priority disease. When the surveillance focal person was questioned as to why he didn't report, he said, "No priority diseases were detected. That is why I didn't submit a report." The DSO instructed the facilities to capture all priority diseases, including those previously missed or unreported, and classify them for reporting to the district surveillance office as per national IDSR guidelines.
Question 7. Do you agree with the reasons given by Facility A and C? Justify your answer.
Question 8. What actions should the DSO take to ensure health facilities have the capacity to report?
Question 9. What action will you take in Facility B as a DSO to ensure reporting of priority diseases?
With support from the World Health Organization (WHO), MoH and other organizations, the DSO conducted a refresher training for IDSR for health workers at the three health facilities. During the training, it was observed that trainees were having challenges with identification and classification of priority diseases. After training, the DSO followed up with trainees at the health facilities to assess how the case definitions were applied. A four-year old girl climbed a mango tree, but fell in the process. A day after, she developed weakness in the arm and legs, making it difficult for her to walk. 5. An eleven-year old boy was bitten by a stray dog. A few days later, he started having abnormal tingling sensations with pain at the wound site, fever, and fear of water. The dog died 2 days after onset of his symptoms. 6. A patient was seen in the consulting room 7 days after acute onset of fever and jaundice. 7. A 10-year-old energetic boy in the neighbourhood was suddenly not able to walk for the past two weeks due to weakness in the arm and legs. 8. Two children, aged four and five years old, purchased food from a roadside vendor. Eight hours after eating, one of the children started passing rice-water-like stool with vomiting and severe dehydration. 9. A woman with an unwanted pregnancy terminated the pregnancy. Two weeks after the procedure, she started complaining of a sharp pain in her lower abdomen and died two hours later. 10. A man complained of a suddenly developed fever with cough, conjunctivitis and generalized rash.

Part 2
After training, the DSO instructed each health facility to submit their summary report on priority diseases for the week with a line list of all reported priority diseases over the past six weeks. This would enable the DSO to verify that the weekly summary report reflected an accurate count of priority diseases recorded in the line list. On receiving the reports and line list from the facilities in his district, the DSO analysed the data and developed a district summary report. He then shared this report with the county health team as part of his routine feedback to the county on surveillance activities in his district.

Conclusion
A key consideration in any public health surveillance system is its ability to detect cases at all levels using standard criteria. Uniform protocols, units, and formats for data collection enable comparison of data from different facilities and jurisdictions to detect trends and aberrations. Early detection of an epidemic-prone disease helps in timely intervention to avoid spread of an infection. Surveillance units from community to national levels are expected to report reliable data that can influence decision making by authorities at the Ministry of Health. This can be achieved through regular analysis and interpretation of surveillance data.
Although Liberia adopted the IDSR in 2005, the district level was not initially established as a level for reporting. However, the 2014 Ebola outbreak revealed gaps in the surveillance system which included late detection and reporting of suspected cases. Post-Ebola, the IDSR system in Liberia has shown an improvement through implementation and roll-out of revised guidelines by WHO and Ministry of Health. The Liberian Field Epidemiology Training Program improved outcomes measured by IDSR indicators by building the capacity of surveillance officers through field mentorship and hands-on practical training of surveillance activities. The proposed definition for events to be reported by clinicians and health care facilities is: "Any outbreak of disease, OR any uncommon illness of potential public health concern, OR any infectious or infectious-like syndrome considered unusual by the clinician, based on frequency, circumstances of occurrence, clinical presentation, or severity"

Background Reading
The proposed definition of a reportable event for laboratories is: "Any situation considered unusual related to received samples (frequency, circumstances of occurrence or clinical description) OR test results (unexpected number of the same species/subspecies, strain type/subtype or antimicrobial resistance pattern, or failure/uncertainty in diagnostics)" Acute