Understanding the role of the diagnostic ‘reflex’ in the elimination of human African trypanosomiasis

To successfully eliminate human African trypanosomiasis (HAT), healthcare workers (HCWs) must maintain their diagnostic acuity to identify cases as the disease becomes rarer. HAT experts refer to this concept as a 'reflex' which incorporates the idea that diagnostic expertise, particularly skills involved in recognising which patients should be tested, comes from embodied knowledge, accrued through practice. We investigated diagnostic pathways in the detection of 32 symptomatic HAT patients in South Sudan and found that this 'reflex' was not confined to HCWs. Indeed, lay people suggested patients test for HAT in more than half of cases using similar practices to HCWs, highlighting the importance of the expertise present in disease-affected communities. Three typologies of diagnostic practice characterised patients' detection: 'syndromic suspicion', which closely resembled the idea of an expert diagnostic reflex, as well as 'pragmatic testing' and 'serendipitous detection', which depended on diagnostic expertise embedded in hospital and lay social structures when HAT-specific suspicion was ambivalent or even absent. As we approach elimination, health systems should embrace both expert and non-expert forms of diagnostic practice that can lead to detection. Supporting multidimensional access to HAT tests will be vital for HCWs and lay people to practice diagnosis and develop their expertise

A Mixed Methods Study of a Health Worker Training Intervention to Increase Syndromic Referral for Gambiense Human African Trypanosomiasis in South Sudan

BACKGROUND: Active screening by mobile teams is considered the most effective method for detecting gambiense-type human African trypanosomiasis (HAT) but constrained funding in many post-conflict countries limits this approach. Non-specialist health care workers (HCWs) in peripheral health facilities could be trained to identify potential cases for testing based on symptoms. We tested a training intervention for HCWs in peripheral facilities in Nimule, South Sudan to increase knowledge of HAT symptomatology and the rate of syndromic referrals to a central screening and treatment centre. METHODOLOGY/PRINCIPAL FINDINGS: We trained 108 HCWs from 61/74 of the public, private and military peripheral health facilities in the county during six one-day workshops and assessed behaviour change using quantitative and qualitative methods. In four months prior to training, only 2/562 people passively screened for HAT were referred from a peripheral HCW (0 cases detected) compared to 13/352 (2 cases detected) in the four months after, a 6.5-fold increase in the referral rate observed by the hospital. Modest increases in absolute referrals received, however, concealed higher levels of referral activity in the periphery. HCWs in 71.4% of facilities followed-up had made referrals, incorporating new and pre-existing ideas about HAT case detection into referral practice. HCW knowledge scores of HAT symptoms improved across all demographic sub-groups. Of 71 HAT referrals made, two-thirds were from new referrers. Only 11 patients completed the referral, largely because of difficulties patients in remote areas faced accessing transportation. CONCLUSIONS/SIGNIFICANCE: The training increased knowledge and this led to more widespread appropriate HAT referrals from a low base. Many referrals were not completed, however. Increasing access to screening and/or diagnostic tests in the periphery will be needed for greater impact on case-detection in this context. These data suggest it may be possible for peripheral HCWs to target the use of rapid diagnostic tests for HAT

Changing landscapes, changing practice: negotiating access to sleeping sickness services in a post-conflict society.

For several decades, control programmes for human African trypanosomiasis (HAT, or sleeping sickness) in South Sudan have been delivered almost entirely as humanitarian interventions: large, well-organised, externally-funded but short-term programmes with a strategic focus on active screening. When attempts to hand over these programmes to local partners fail, resident populations must actively seek and negotiate access to tests at hospitals via passive screening. However, little is known about the social impact of such humanitarian interventions or the consequences of withdrawal on access to and utilisation of remaining services by local populations. Based on qualitative and quantitative fieldwork in Nimule, South Sudan (2008-2010), where passive screening necessarily became the predominant strategy, this paper investigates the reasons why, among two ethnic groups (Madi returnees and Dinka displaced populations), service uptake was so much higher among the latter. HAT tests were the only form of clinical care for which displaced Dinka populations could self-refer; access to all other services was negotiated through indigenous area workers. Because of the long history of conflict, these encounters were often morally and politically fraught. An open-door policy to screening supported Dinka people to 'try' HAT tests in the normal course of treatment-seeking, thereby empowering them to use HAT services more actively. This paper argues that in a context like South Sudan, where HAT control increasingly depends upon patient-led approaches to case-detection, it is imperative to understand the cultural values and political histories associated with the practice of testing and how medical humanitarian programmes shape this landscape of care, even after they have been scaled down

Distribution of correct test responses for individual symptoms, before and after HAT training.

<p>The numbers of people providing an answer for each symptom-association varied between tests. Pre-training (Pre-) test n = 107–113, post-training (Post-) test n = 106–110, post-intervention evaluation (Eval-) test n = 54–55. “Don't know” responses were categorised as incorrect. Fever for 2 days, cough and abdominal pains are not associated with HAT. *McNemar's p-value indicates a significant (p<0.05) increase in correct associations between pre-training and post-intervention evaluation tests.</p

HAT patient screening rates before and after HAT training, by referral route.

<p>PY: Person-years of observation.</p

Proportion of HCWs and facilities who made at least one HAT referral, before and after HAT training.

<p>*An additional 5 HCWs from 4 facilities made HAT referrals after being trained by HCWs who attended the workshop. If only HCWs who were followed-up are considered, the proportion who ever referred for HAT before the training was 25/97 (26.8%) and the proportion who referred in the month before training was 11/97 (11.3%). For facilities, these proportions were 16/49 (32.6%) and 9/49 (18.4%), respectively.</p

Associations between demographic variables and mean test scores.

<p>*For differences by demographic variables in test scores at one time point significant at the 0.05 level, p-values are shown in bold font. Where p-values are not shown (-), numbers were too small for analysis of significance.</p>†<p>Kruskal-Wallis tests were used to compare mean scores between demographic sub-groups.</p

Numbers and types of peripheral health facilities represented at HAT training and followed-up during the evaluation period.

<p>PHCU = Primary health care unit, the lowest level of healthcare available to communities.</p><p>PHCC = Primary health care centre, the next highest level of care.</p

Source of referral for patients screened at hospital for HAT, by month of screening.

<p>Source of referral for patients screened at hospital for HAT, by month of screening.</p

Mean overall test scores, before and after HAT training.

<p>*In the pre-training test, 10/123 participants did not complete the test, 97/113 test-takers answered the question for all 14 symptoms. In the post-training test, 13/123 did not complete the test, 97/110 answered all 14 symptoms. In the post-intervention evaluation test, 68/123 did not complete the test, 52/55 answered all 14 symptoms. SD = Standard deviation.</p