Evaluation of the notifiable diseases surveillance system in sanyati district, Zimbabwe, 2010-2011

Introduction The Notifiable disease surveillance system (NDSS) was established in Zimbabwe through the Public Health Act. Between January and August 2011, 14 dog bites were treated at Kadoma Hospital. Eighty-six doses of anti-rabies vaccine were dispensed. One suspected rabies case was reported, without epidemiological investigations. The discrepancy may imply under reporting of Notifiable Diseases. The study was conducted to evaluate the NDSS in Sanyati district. Methods A descriptive cross sectional study was conducted. Healthcare workers in selected health facilities in urban, rural, and private and public sector were interviewed using questionnaires. Checklists were used to assess resource availability and guide records review of notification forms. Epi InfoTM was used to generate frequencies, proportions and Chi Square tests at 5% level. Results We recruited 69 participants, from 16 facilities. Twenty six percent recalled at least 9 Notifiable diseases, 72% correctly mentioned the T1 form for notification, 39% correctly mentioned the forms completed in triplicate and 20% knew it was a legal requirement to notify. Ninety six percent of respondents indicated willingness to participate, whilst 41% had ever received feedback. Three out of 16 health facilities had T1 forms. Conclusion NDSS is useful, acceptable, simple, and sensitive. NDSS is threatened by lack of T1 forms, poor feedback and knowledge of health workers on NDSS. T1 forms and guidelines for completing the forms were distributed to all health facilities, public and private sector. On the job training of health workers through tutorials, supervision and feedback was conducted.


Introduction
Public health surveillance is the ongoing, systematic collection, analysis, interpretation, and dissemination of data about a healthrelated event for use in public health action to reduce morbidity and mortality and to improve health [1]. A Notifiable disease is one required to be reported to local government health officials when diagnosed, because of infectiousness, severity, or frequency of occurrence [2].
The Notifiable Diseases Surveillance system (NDSS) supports case detection and public health interventions, estimates the impact of Hemorrhagic fever (e.g. Ebola, Marburg, Crimean Congo), and Yellow fever [3].
The T1 form is used for notification of infectious diseases as described by the Public Health Act chapter 15:09, section 17 [3]. It is a case based system for prompt reporting of Notifiable diseases.
Any health worker who comes in contact with a suspected or confirmed case of a Notifiable disease should immediately notify the District Medical Officer by telephone, radio or any other fast method available, within 24 hours of diagnosis. This is followed with a T1 form completed in triplicate [4]. If more than 5 cases of Notifiable cases of a disease occur in a specified time, a line list is maintained, which includes the first five cases [5]. The district compiles a summary of Notifiable diseases on the T2   form at the end of each month and summarizes all notifications for   the month The T2 form completed by the district should reach the provincial office by the 10th of the following month [5]. The province summarizes all the districts T2 forms onto one Provincial T2 form, which is forwarded to the head office by the 24th of the month and a national summary is also produced [5]. Between reporting Notifiable diseases. This is a cause for concern to the district and provincial health management as this can result in untimely investigation and control of communicable diseases.
The study was conducted to evaluate the Notifiable Disease Surveillance System (NDSS) in Sanyati district, for the period January 2010 to June 2011. The study specifically set out to: describe the NDSS in Sanyati District; assess the health worker knowledge on the NDSS; assess the usefulness of the NDSS; assess the NDSS attributes; determine the cost of running the NDSS; and to come up with recommendations to improve the NDSS. A pre tested interviewer questionnaire was administered to health workers, and managers. The questionnaires were used to collect information on the knowledge levels among the health workers and managers on the NDSS, assess usefulness, and attributes of the NDSS. Checklists were used to assess for resource availability, and for guiding the desk review of T1 Notification Forms. Outbreak reports, minutes of meetings, spot maps and graphs were checked to verify responses. Data were captured into Epi-Info TM (CDC 2011).

Methods
Epi-Info TM was used to generate frequencies, proportions, and graphs and conduct Chi Square test for statistical significance.
Permission was obtained from the local health authorities, and the Health Studies Office in Zimbabwe. Informed written consent was obtained from the study participants. Confidentiality was assured and maintained throughout the study.

Results
Four key informants were interviewed. Sixty nine (69) health workers were interviewed. Fifty five (80%) of the respondents were from the private sector, whilst 14 (20%) were from private sector.
Fifty six respondents were nurses, 9 were environmental health and four were doctors. The median duration in employment was five years in the public sector (Q1=2, Q3=11), and 11 years in private sector (Q1=7, Q3=13).

Description of the T1 Surveillance System
In Sanyati district, the T1 surveillance system is paper based from the health centre/hospital level. Whenever a Notifiable disease is encountered at the health facilities notification is done using T1 forms are which completed in triplicate, but sometimes in duplicate and sent to the district office as soon as possible. The district office is notified immediately by phone or radio. The completed T1 forms are sent by health facility transport (motor cycle, or vehicle), according to 62% of the respondents, whilst a general hand or other health worker is sent using public transport with the forms (16%).
In the urban setting, no Notifiable disease had been reported in the period under review, but key informants indicated that the T1 forms are completed in triplicate, and a copy is sent to the City Health Director, and another copy forwarded to the District Office. An outbreak of cholera in early 2010 had not been notified using T1 forms, but line lists were completed. Feedback is through investigation of the reported cases by the district team, and through supervisory visits. There is no written feedback to the health facilities. Disease surveillance meetings are not done at the district level. Sixty Nine percent (69%) and 13% of respondents had received supervision within one month, and three months prior to the interview, respectively. Seventy three (73%) percent of the respondents mentioned that surveillance is discussed during visits.

However, a review of visitors book shows that Vaccine Preventable
Diseases (VPD's) and TB/HIV issues are mainly discussed during visits.

Simplicity
Key informants indicated that it was easy to orient staff in NDSS.
Twenty nine health workers (42%) had completed the T1 form before. Of these, 10 said they could complete the form in less than 10 minutes; whilst 16 completed the form in more than 15 minutes.
Nineteen respondents said completing the T1 form was easy and three, from public sector, mentioned that completing the form was difficult. The key informants indicated that it was easy to analyze the data on a T1 form as the form had few fields, depicting the person, place and time. Analysis was considered simple as the analysis is done case by case, and then aggregated into the T2 form, monthly. were not notified using T1 forms, but line lists were available.

Representativeness of the surveillance system
Key informants indicated that all the health facilities in the private and public sector participate in NDSS. The proportion of the population who do not use the formal system in Sanyati district is not known, thus, could not determine the population covered by the NDSS.

Usefulness
The health worker perception on usefulness of surveillance data and verification on usefulness were checked. Figure 2 shows the health worker perception of usefulness of the NDSS. High proportions of respondents perceived NDSS as useful:

Evident Usefulness of NDSS
Only three Notifiable diseases were reported during the period under review. Eleven of the 12 public health facilities had spot maps, which targeted mainly vaccine preventable diseases (VPDs).
Use of NDSS data for planning and mobilizing resources was noted with the EPR cholera plan in Kadoma City; repair of radio communication system in rural Sanyati; vaccination of dogs and cattle in rural Sanyati, in response to rabies and anthrax outbreaks, after sharing information with respective stakeholders.

The Cost of Operating the System
The average cost of notifying a single case was calculated, for the current paper based system. The cost was also calculated for an electronic system, if the NDSS adopt the mobile phone based method of data transmission, similar to the one being used for the weekly disease surveillance system (WDSS). The Table   2 summarizes the average cost of notifying a single case of Notifiable disease. The paper based system is more expensive, averaging US$18.15, compared to a situation where the mobile phone can be adapted to send T1 forms, US$1.55. For the paper based system, almost 90% of the cost is for transporting the T1 form to the district office.

Discussion
The study was conducted to assess the knowledge of health workers on the T1surveillance, assess attributes of the T1  [7]. Consistent findings obtained in the United States, where health workers were not aware of legal requirements to report, lacked knowledge of which diseases to report, and assumed that someone will notify [8].
In this study, the poor knowledge on the NDSS could be due to lack of training. This is consistent with several studies done in Zimbabwe which found that lack of training in surveillance threatened the performance of surveillance systems [9][10][11]. In Tsholotsho district, was no feedback at all [7].
In terms of data quality, all twelve T1 forms were notified on date of diagnosis. Ninety seven percent of the respondents indicated that T1 forms are checked for quality before being sent to the next level.
This is usually the duty of the sister in charge, yet only 3 out of 11 SIC's were oriented in NDSS. The completed T1 forms were of poor quality, as they lacked some important information such as diagnosis and name of health facility. This may pose challenges in conducting investigations, analysis of data and generating reports.
Further, conclusions on the timeliness and completeness of T1 forms may not be generalizable in the district, as less than the targeted 30 T1 forms reviewed, from three health facilities.

Competing interests
The authors declare no competing interests.

Authors' contributions
All authors were responsible for the conception of the problem, design, collection, analysis and interpretation of data and drafting the final article. The manuscript was read and approved by all authors.

Acknowledgments
Special thanks go to Kadoma City Council, Health Studies Office, and CDC Zimbabwe/Atlanta for the technical support received in conducting the study. Special thanks go to my family and colleagues who gave guidance and support during the study.