Evidence-Responsive Health Training to HIV/TB Risks in Namibia

Abstract.

Training health-care students in settings with high-prevalence HIV and tuberculosis (TB) presents a challenge to reduce the risk of infection during their clinical training while maintaining quality education. We sought to gauge the risk of exposure to HIV and TB and identify associated variables through two cross-sectional surveys of health students at the University of Namibia. In the HIV exposure survey, overall almost one-quarter of students (N = 367) reported exposure to HIV—most often needle-stick injury—with a much higher rate reported in senior years (73% in year 6). One in 10 students responding to the TB survey were found to have been exposed to TB (N = 290). Regression analyses suggested that time-related factors were a common predictor of risk of both HIV and TB in this setting. We consider that the overall exposure rate to HIV and TB was high, suggesting that training could be improved to reduce the risks of exposure.

HIV and consequently tuberculosis (TB) continue to impact disproportionately on sub-Saharan Africa.^1,2 This has put a huge burden on frail health-care infrastructure and workforce in the region that also exhibits the greatest scarcity of health-care workers globally.³ A further challenge in meeting the health needs of the population in terms of medical management of HIV and TB is in reducing nosocomial spread of these diseases as well as reducing the risk of exposure of health-care workers treating patients. These risks are also well documented in the training of health-care students.^4–7

There have recently been concerted efforts in the sub-Saharan African region to increase the numbers of health-care workers with Namibia and Botswana, for example, commencing training for medicine and pharmacy for the first time in their history, representing a shift toward sustainable training models.^8,9 However, as health training should be practical and responsive to health needs in a particular setting, it is inevitable that health-care students will be exposed to HIV and TB in these high-prevalence settings. Health training institutions must respond to this risk in empowering health students to protect themselves and create a culture at the pre-service level of awareness in occupational health management. In addition, institutional policy and training practices should be responsive to untoward events and adapt accordingly, which requires continuous reporting and monitoring.¹⁰

Since 2010, the University of Namibia has commenced training of a number of different health cadres, including medicine and pharmacy that has resulted in more than 200 medical graduates and 100 pharmacy graduates to date (Figure 1). The government has invested heavily in funding a purpose-built health campus located between the country’s two largest referral hospitals in the capital city, as well as extending training to the most populous regions in the north of Namibia, in particular, and nationwide through field placements and clinical rotations. There is a significant interprofessional component of training with a postgraduate clinical pharmacy training now empowering graduates to embrace patient-focused care as part of a multidisciplinary team. To this aim, medical and pharmacy students undergo training in clinical settings from the second year of study that exposes them to the risk of HIV and TB. To protect the students, they are required to be vaccinated against the most significant threats (e.g., hepatitis A and B) and are given training in infection control and occupational health. This includes, for example, good hand hygiene practices, use of N95 masks to prevent infection of TB, and responding to needle-stick incidents and other potential exposures to HIV.

Figure 1.

Development and intake of students in new health programs in the UNAM Faculty of Health Sciences. This figure appears in color at www.ajtmh.org.

In 2018, to better monitor and audit the risk of exposure to HIV and TB, we conducted two cross-sectional surveys of the student population on risk exposure, untoward events, and knowledge; this was complemented by optional Mantoux testing for latent TB infection.

The first survey sought to gauge occupational exposure to HIV of health students in the clinical setting. A questionnaire was circulated to student groups following lectures and also in the clinical setting between September and November 2018. After excluding health-care workers and interns who had completed the questionnaire, there were 367 responses of which the majority (73%) were medical students and about two-thirds were female (67.8%). Most year groups responded well to the survey except for the 5th year medical students who were on clinical placements in the north of Namibia at the time (4.1% response of total sample). Overall, almost one-quarter of students (23.4%) reported ever having been exposed to HIV through their training; 9.5% reported exposure on more than one occasion and the vast majority of all exposures (n = 141) were reported either as needle-stick injury (48.9%) or splashing of blood/bodily fluids on mucous surfaces (41.8%). Most students (68.5%) were tested for HIV after the incident with 57.8% receiving postexposure prophylaxis (PEP)—all but two students within a 24-hour period. More than half of students considered that they had not been sufficiently trained on what to do in the event of occupational exposure (54.0%) or PEP (59.1%). In exploring factors related to reported exposure, medical students were more likely to report exposure than all other groups (χ² = 13.43; P < 0.001), older year groups were more likely to be exposed (χ² = 104.5; P < 0.001) with students in the final (6th) year reporting 73% exposure, and those exposed more likely to report adequate training (χ² = 6.1; P < 0.014) and exhibiting higher knowledge score (Mann–Whitney; P < 0.001). No associations were observed between exposure and gender or waking hours at the time of the incident. Logistic regression suggested that of all the associated variables, year group alone was associated with exposure with the model predicting 83.2% overall (Table 1).

Table 1.

Predictors of HIV exposure (model 1) and latent TB infection (model 2) among health students at the University of Namibia in 2018

Variable	χ2*	AOR (95% CI)
Model 1: Predictors of HIV exposure
Academic year 1 (reference)	43.472†	–
Academic year 2	30.574†	0.031 (0.009–0.106)
Academic year 3	33.912†	0.05 (0.018–0.137)
Academic year 4	13.557†	0.144 (0.051–0.404)
Academic year 5	10.755†	0.061 (0.012–0.325)
Academic year 6	5.247†	0.349 (0.142–0.859)
Medical/nonmedical students	0.018	1.058 (0.461–2.43)
Training reported on HIV postexposure prophylaxis	0.132	1.122 (0.604–2.081)
Knowledge score reported	0.536	1.107 (0.843–1.455)
Constant	0.565	1.700
Model 2: predictors of latent TB infection
Academic year 1 (reference)	1.628	–
Academic year 2	0.241	0.615 (0.088–4.288)
Academic year 3	0.143	0.766 (0.192–3.054)
Academic year 4	0.034	0.88 (0.228–3.393)
Academic year 6	1.471	0.339 (0.059–1.948)
Gender	1.553	0.581 (0.248–1.365)
Private/public school	2.874	3.079 (0.839–11.299)
Previous involvement in TB care	0.092	0.839 (0.271–2.6)
TB hospital rotation	0.132	0.804 (0.248–2.608)
Age	7.556†	1.191 (1.051–1.349)
Constant	11.602	0.002

TB = tuberculosis. Adjusted odds ratio (AOR) and 95% CI were calculated using binary logistic regression and all variables entered by enter method. Nagelkerke R² model 1 was 0.35 and for model 2 was 0.16.

* Wald statistic, which identifies variables that significantly contribute to the model.

† P < 0.05.

The second survey similarly used a questionnaire to collect data on demographics, potential risk factors, and knowledge and also tested respondents for latent TB risk. The survey was conducted during August and September 2018, and 290 responses were received that had a known latent TB result (positive/negative), excluding two students who reported having previously contracted TB (0.7%). Most responses were from medical students (78.3%) and females (69.3%) with a good response from all year groups. Three-quarters of respondents had received secondary education in the state sector and most within the capital city (65.4%). More than half reported being vaccinated with BCG (53.4%), although many students were unsure of their status (44.1%), and the majority reported knowing their HIV status (72.8%). Student reported living with a median of five people before studying, and 38 students (13.1%) reported that someone in their home had been diagnosed and treated for TB. More than half reported having cared for TB patients (55.5%) with 40.1% having rotated through the TB wards/hospital. A positive Mantoux test was found in 9.7% of students. Exploring associations between latent TB test result and other variables suggested higher than expected positive results for students who rotated through the TB hospital (χ² = 5.46; P = 0.019), and associations approaching significance with age (Mann–Whitney; P = 0.052), gender (χ² = 3.61; P = 0.057), year of study (Mann–Whitney; P = 0.066), type of school attended (χ² = 3.18; P = 0.075), and having ever been involved in TB care (χ² = 3.18; P = 0.075). However, applying logistic regression suggested that the only predictor of test result was age with a model predicting 90.7% overall (Table 1).

Through two surveys, we sought to evaluate the occupational health exposure of health students to HIV and TB in a relatively new health training initiative in Namibia. Overall, almost one-quarter of students were potentially exposed to HIV—although this risk increased dramatically by the final year of study for medical students—and around one in 10 students had evidence of previous or current infection with TB. Interestingly, through logistic regression analysis, the predictors of both HIV and TB exposure were time related—year group and age—suggesting that the longer students are in training the more likely they are to be exposed. A range of associations were observed between exposure risk and other variables, including rotation site (TB hospital), perceived adequacy of training and preparation, knowledge, and training program, and these are the cause for concern and continued monitoring. There are stark differences between the dependent variables in the two surveys—usually needle-stick injury versus silent infection of TB—that may explain why students who were exposed to HIV had higher knowledge levels, whereas in the TB exposure survey, there was no difference in knowledge score between those exposed or not. In addition, an untoward event of HIV exposure is clearly more profound than the exposure to TB that may have occurred at any point in the student’s life. Our concern, however, is that if exposure to either HIV or TB is associated with time-related variables for training programs spanning between 4 and 6 years, then it suggests a very high risk during this time and demands better attention to intervention. It is clear that the occupational health training should be improved and that rather than a one-off event, this should be offered repeatedly as a mandatory component of training. Various aspects of the occupational health training should be aligned, for example, unifying the training done in different year groups and training programs with the vaccination program. It is vital to include all the student groups in future—particularly nursing—so that the risk of exposure is better mapped to identify the risk factors at play. Continued monitoring should also be routinely incorporated, bringing together the two surveys and consolidating the data collected. In addition, it may be worth using interferon-gamma testing for latent TB as, arguably, a more reliable method for tracking TB latency, although this has significant cost implications. This may establish a better dataset for determining recent infection as well as boost the response rate—the smaller sample size for the TB occupational health survey is likely due to students not wanting to undertake the Mantoux test or not returning for the test reading within 72 hours.

Certainly, results from these two surveys have implications for both practice and training. It would be pertinent both to follow up on the students once they have graduated and entered into practice and also estimate the exposure risks of HIV and TB among health-care practitioners in Namibia generally. Knowing that the University of Namibia is not the only institution to set up new health training programs in a setting of high HIV and TB prevalence, it would also be important to repeat or combine the surveys in other settings in the region and to develop better resources for training.