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Use and Acceptability of HIV Self-Testing Among First-Time Testers at Risk for HIV in Senegal

  • Carrie E. LyonsEmail author
  • Karleen Coly
  • Anna L. Bowring
  • Benjamin Liestman
  • Daouda Diouf
  • Vincent J. Wong
  • Gnilane Turpin
  • Delivette Castor
  • Penda Dieng
  • Oluwasolape Olawore
  • Scott Geibel
  • Sosthenes Ketende
  • Cheikh Ndour
  • Safiatou Thiam
  • Coumba Touré-Kane
  • Stefan D. Baral
Open Access
Original Paper

Abstract

HIV Self-Testing (HIVST) aims to increase HIV testing coverage and can facilitate reaching the UNAIDS 90-90-90 targets. In Senegal, key populations bear a disproportionate burden of HIV and report limited uptake of HIV testing given pervasive stigma and criminalization. In these contexts, HIVST may represent a complementary approach to reach populations reporting barriers to engagement with existing and routine HIV testing services. In this study, 1839 HIVST kits were distributed in Senegal, with 1149 individuals participating in a pre-test questionnaire and 817 participating in a post-test questionnaire. Overall, 46.9% (536/1144) were first-time testers and 26.2% (300/1144) had tested within the last year; 94.3% (768/814) reported using the HIVST, and 2.9% (19/651) reported a reactive result which was associated with first-time testers (p = 0.024). HIVST represents an approach that reached first-time testers and those who had not tested recently. Implementation indicators suggest the importance of leveraging existing community structures and programs for distribution.

Keywords

HIV Self-Testing Key populations Senegal Sub-Saharan Africa 

Resumen

El autodiagnóstico del VIH (ADVIH) busca incrementar la cobertura de las pruebas del VIH y puede facilitar el alcance de los objetivos 90-90-90 de ONUSIDA. En Senegal, los grupos de población clave soportan una carga desproporcionada del VIH y reportan una utilización limitada de las pruebas del VIH, dada la generalización del estigma y la criminalización. En este contexto, el ADVIH puede servir como enfoque complementario para alcanzar a las poblaciones que reportan barreras al compromiso con los servicios de pruebas del VIH existentes y de rutina. En este estudio se distribuyeron 1839 ADVIH en Senegal, donde 1149 individuos participaron en una encuesta antes de recibir la prueba y 817 participaron en una encuesta después de recibir la prueba. En general, el 46.9% (536/1144) se realizó la prueba por primera vez y el 26.2% (300/1144) se habían realizado una prueba en el último año; el 94.3% (768/814) reportó utilizar el ADVIH y el 2.9% (19/651) reportó un resultado reactivo asociado con realizar la prueba por primera vez (p = 0.024). El ADVIH representa un enfoque que alcanzó a las personas que realizaron la prueba por primera vez y a quienes no se habían realizado la prueba recientemente. Los indicadores de implementación sugieren la importancia de aprovechar las estructuras comunitarias y los programas de distribución existentes.

Introduction

Increasing coverage of HIV testing and early detection of seroconversion among people living with HIV is essential for effectively responding to the HIV pandemic. Early detection of HIV and initiation of antiretroviral therapy (ART) significantly reduces HIV-related morbidity and mortality, and can improve the quality of life for people living with HIV while also eliminating the risk of onward HIV transmission [1, 2, 3]. Similarly, awareness of one’s negative HIV serostatus is important for prioritizing prevention strategies especially in the context of increasing availability of pre-exposure prophylaxis (PrEP) [4, 5]. HIV self-testing (HIVST) is emerging as an important tool to potentially increase the uptake and the frequency of HIV testing in populations at increased risk for acquiring HIV such as key populations who may avoid HIV testing services because of stigma and criminalization of their sexual practices, orientation, or occupation, or even the criminalization of HIV transmission [6]. Approximately 48 countries have established an HIVST supportive policy and far more countries have policies under development, including several across sub-Saharan African [7, 8]. Given the rapid adoption of HIVST globally, WHO guidelines have been developed to support the implementation and scale-up of ethical, effective, acceptable, and evidence-based approaches to HIVST [9].

HIVST can potentially overcome barriers to HIV testing uptake and accessibility by placing the locus of control of testing on the individual, increasing confidentiality, and allowing members of marginalized and stigmatized groups to test in settings of privacy, safety, and with dignity [10]. Oral HIVST has been shown to improve HIV testing coverage and to be acceptable among diverse populations across varied settings [11, 12, 13, 14, 15, 16]. However, there is currently limited evidence on acceptability of HIVST across Western and Central Africa despite the need to understand the acceptability and strategies for effective implementation across the region [8].

The West African country of Senegal is one of the countries in sub-Saharan Africa where an HIVST policy is currently under development [8]. Senegal has a concentrated HIV epidemic with a prevalence among adults of reproductive age consistently under 1%, and a high burden among specific key populations [17]. In Senegal, HIV disproportionately affects men who have sex with men (MSM), female sex workers (FSW) and people who inject drugs (PWID) with prevalence estimates of 23.5%, 3.3%, 10.2%, respectively [18, 19]. In Senegal, same-sex practices are criminalized and sex work for cisgender women is legal but highly regulated [20]. Stigma has been shown to be a barrier to uptake of HIV testing and accessing other HIV prevention and treatment services. In many places, there is stigma specifically associated with seeking HIV testing [21, 22]. Frequent or regular HIV testing may be perceived by healthcare providers as disclosing a stigmatized behavior, and stigma relating to access to health services among key populations has been reported to be high [18]. Low rates of testing may be affecting Senegal’s progress towards epidemic control among key populations and achieving the UNAIDS 90-90-90 targets for all [23]. While available data are limited, UNAIDS estimates that only 71% of adults living with HIV know their status, of which only 58% are receiving ART [24.] However, uptake of HIV services has been shown to be lower among key populations, with a recent study estimating that only 13% of MSM and 55% of FSW living with HIV reported to be aware of their seropositive status [18].

Given the HIV epidemic profile in Senegal and the limited uptake of HIV prevention and treatment services among key populations in the country, HIVST may represent an impactful strategy for increasing the uptake and coverage of HIV testing and accelerating progress towards achieving 90-90-90 goals. This study aimed to assess the acceptability of HIVST for key populations and people in their social and sexual networks and secondly, to assess the effectiveness of HIVST in reaching first-time testers. These results will inform appropriately scaled implementation of HIVST in Senegal and across West Africa.

Methods

This is a pilot study which distributed HIVST kits through targeted venues and recruited individuals through convenience sampling to participate in pre and post HIVST socio-behavioral questionnaires.

HIVST Distribution

OraQuick HIV Self-Test Kits (Orasure Technologies, Inc) were distributed to individuals in Dakar and Ziguinchor through venue and social network-based distribution. The HIVST kits included an OraQuick test device, written and pictorial step-by-step instructions, supplementary information on the test and HIV, and a referral card with information for confirmatory testing sites and study contacts. Instructions and supplementary information were provided in French and Wolof and adapted to the Senegalese context.

HIVST kit distribution and participant recruitment was led by study partner, Enda Santé, and aimed to reach populations with increased vulnerability of HIV acquisition and high levels of health care related stigma, including MSM, FSW, PWID, and clients of FSW. [20].

The venue-based approach for distribution and recruitment utilized directly assisted distribution of HIVST and was conducted through outreach to sex work venues, bars, nightclubs, hot spots, and mobile clinics, as well as health facilities that provide services to key populations. Venues were selected based on recommendations of community partners with previous experience in the communities, and leveraged existing programmatic activities. Directly assisted distribution of HIVST followed the WHO definition [9] and was led by trained distributors who provided pre-test instructions, test information, demonstration of proper HIVST use, and education on the importance for confirmatory testing, irrespective of a test reactivity. When possible, the participant was given the choice to either self-administer in a private space on-site with a peer educator available, or to take their HIVST kit away with them to test later.

A small sample of additional HIVST kits were distributed through social network-based unassisted distribution. The social network-based approach was focused on providing a primary recipient with one HIVST kit for themselves and two additional kits to distribute to individuals within their network. Social network-based distribution leveraged venue-based distribution to engage the primary HIVST recipient, who received the HIVST kits directly from the trained distributor. The primary recipient then distributed to secondary recipients through indirect, unassisted distribution as defined by WHO [9.] Secondary recipients only received written instructions and information contained within the HIVST kit.

Data Collection

Convenience sampling was used to recruit individuals into the study at the time of HIVST kit distribution. Individuals receiving the HIVST kits through directly assisted venue-based distribution were asked if they wished to participate in a pre- and post-test survey. Data from social network-based distribution were only obtained from the primary recipient as follow up was not possible for the network-based HIVST kit recipients. Participants were eligible if they reported being 18 years of age or older; capable of and willing to provide informed consent; agreed to use the HIVST; and spoke Wolof and/or French. Participation was voluntary, and individuals could receive an HIVST kit regardless of survey participation. All pre- and post-test surveys were administered to eligible participants by trained interviewers. Among consenting participants, an interviewer administered pre-test surveys at the distribution site before HIVST utilization. Pre-test surveys captured information on demographic characteristics, HIV risk behaviors, HIV testing history, and motivation for testing.

Among individuals who opted to test at the HIVST distribution sites, the HIVST was collected through a test disposal box after self-administration and was read immediately. The result was logged to track the overall results observed, but not connected to the individual participant. This approach was used to compare aggregate level results to those self-reported in the post-tests. Post-test surveys assessing self-reported HIVST use and acceptability were conducted by phone two weeks after the HIVST kit distribution. Data were not obtained from secondary recipients.

Ethical review and approval were provided by the National Research Ethics Committee in Senegal and the Johns Hopkins School of Public Health Institutional Review Board.

Measures

Key population characteristics were self-reported. Sex worker was defined as reporting exchanging sex for money or goods, and with more than half of income being from selling sex in the past 6 months. Male sex workers (MSW) were defined as sex workers above, as well as being assigned male sex at birth; and FSW were defined as sex workers as above and assigned female sex at birth. MSM was defined as being assigned the male sex at birth and ever having oral or anal sex with another man. Transgender women were defined using a two-step gender assessment of reporting male sex assigned at birth and gender identification as a woman. PWID were defined as ever having injected illicit drugs. Key population categories were not mutually exclusive. Key population was defined as meeting the criteria of at least one of the six key population categories.

First-time testers were defined as individuals who self-reported never having received an HIV test prior to the pre-test questionnaire. HIVST reactivity results were collected in two ways: 1. Results collected from used HIVST at the distribution sites; and 2. Self-reported HIVST results from those who participated in the post-test phone survey. Acceptability measures were informed by The Society for Implementation Research and Collaboration Indictor Review, however, have not yet been validated [25.]

Statistical Analyses

Demographic characteristics and HIV testing history were determined from pre-test questionnaires. Logistic regression was used to assess the crude relationship between HIV testing history (first-time vs. previous testers), demographic characteristics, and HIV risk behaviors. Multiple multivariable logistic regression models were developed to separately assess each demographic characteristic, HIV testing history, HIV risk behaviors as primary predictors of first-time testers and adjusted for a priori demographic characteristics. Pearson’s Chi squared tests were used to assess the crude relationships between first-time testers and HIVST use and acceptability, as well as the relationships between self-reported HIVST result and use and demographic characteristics. A significance value of p < 0.05 was used for all analyses.

Results

Distribution and Study Participation

A total of 1839 HIVST kits were distributed between April 2017 to June 2018, and 62.5% (1149/1839) of recipients participated in the pre-test questionnaire before receiving the HIVST (Table 1). Among pre-test participants, 71.1% (817/1149) participated in the follow up post-test questionnaire.
Table 1

HIVST distribution and data collection summary in Senegal

 

n/N

%

HIVST kits distributed

1839

100

Pre-test participants

1149/1839

62.5

Post-test participants among those who participated in the pre-test

817/1149

71.1

Received additional HIVST for secondary distribution among post-test respondents

48/810

5.9

Distributed HIVST for secondary distribution among post-test respondents

36/45

80.0

Gave HIVST to someone else, although did not receive additional HIVST for secondary distribution

9/730

1.2

HIVST results with positive reactivity among those collected at the distribution sites

76/1407

5.4

Among post-test respondents, 5.9% (48/810) had received additional HIVST kits for secondary, unassisted distribution, of which 80.0% (36/45) distributed the additional HIVST kits. Among individuals not provided additional HIVST kits for unassisted distribution, 1.2% (9/730) gave their HIVST kit to someone else.

Demographic Characteristics

Among participants who completed the pre-test, 47.9% (539/1125) were in Dakar and 52.1% (586/1125) were in Ziguinchor (Table 2). Among pre-test participants, 25.3% (286/1130) were aged 18–24 years of age, 32.7% (370/1130) were 25–30 years, and 42.0 (474/1130) were 31 years and older. Overall, 52.9% (607/1148) reported female and 47.1% (541/1148) reported male sex at birth. Demographic characteristics of individuals who participated in the post-test questionnaire did not differ from the pre-test, except for region (p = 0.011).
Table 2

Demographic characteristics of individuals who participated in pre- and post- HIVST questionnaires

 

Pre-test participants

Post-test participants

X2 p value to compare samples

 

N = 1149

N = 817

 

Demographic characteristics

n/N

%

n/N

%

 

Region

    

0.011

 Dakar

539/1125

47.9

437/813

53.7

 

 Ziguinchor

586/1125

52.1

376/813

46.3

 

Age

    

0.947

 18–24

286/1130

25.3

207/803

25.8

 

 25–30

370/1130

32.7

265/803

33.0

 

 31+

474/1130

42.0

331/803

41.2

 

Sex at birth

    

0.226

 Female

607/1148

52.9

454/816

55.6

 

 Male

541/1148

47.1

362/816

44.4

 

Key populationsa

Key population (any)

    

0.451

 Yes

370/1149

32.2

250/817

30.6

 

 No

779/1149

67.8

567/817

69.4

 

Sex worker (all genders)

    

0.841

 Yes

204/1085

18.8

148/772

19.2

 

 No

881/1085

81.2

624/772

80.8

 

Female sex worker

    

0.772

 Yes

155/1085

14.3

114/772

14.8

 

 No

994/1085

85.7

658/772

85.2

 

Male sex worker

    

0.877

 Yes

48/1085

4.4

33/772

4.3

 

 No

1101/1085

95.6

739/772

95.7

 

Men who have sex with men

    

0.417

 Yes

174/1149

15.1

113/817

13.8

 

 No

975/1149

84.9

704/817

86.2

 

People who inject drugs

    

0.230

 Yes

42/1131

3.7

22/807

2.7

 

 No

1089/1131

96.3

785/807

97.3

 

Transgender women

    

0.800

 Yes

20/1148

1.7

13/816

1.6

 

 No

1128/1148

98.3

803/816

98.4

 

HIV testing history

Recent testing for HIV

    

0.435

 Never

536/1144

46.9

358/814

44.0

 

 Yes, but not in the last 12 months

308/1144

26.9

227/814

27.9

 

 Yes, within the last 12 months

300/1144

26.2

229/814

28.1

 

First time testers

    

0.208

 Yes

536/1144

46.9

358/814

44.0

 

 No

608/1144

53.1

456/814

56.0

 

aNot mutually exclusive

Key Populations

Among pre-test respondents, 32.2% (370/1149) self-reported membership of a key population group with 18.8% (204/1085) sex workers specifically, 14.3% (155/1085) FSW and 4.4% (48/1085) MSW; 15.1% (174/1149) MSM; 3.7% (42/1131) PWID; and 1.7% (20/1148) transgender women.

First-Time Testers

Among pre-test respondents, 46.9% (536/1144) of participants were first-time testers, 26.9% (308/1144) had ever tested for HIV but not within the last 12 months, and 26.2% (300/1144) had tested within the last 12 months.

Among key populations, 36.8% (136/370) were first-time testers (Table 3). Among sex workers of all genders, 26.5% (54/204) were first time testers. Among FSW, 20.7% (32/155) were first-time testers, 27.7% (43/155) had tested but not in the last 12 months, and 51.6% (80/155) had tested in the last 12 months. Among MSW, 45.8% (22/48) were first-time testers. Overall, 46.0% (80/174) of MSM, 59.5% (25/42) of PWID, and 55.0% (11/20) of transgender women were first-time testers.
Table 3

HIV testing history among self-reported key populations in Senegal

 

Total

HIV testing history

 

Self-reported key populationa

  

First-time tester

Yes, but not in the last 12 months

Yes, within the last 12 months

 
 

n/N

%

n/N

%

n/N

%

n/N

%

P value

Key population (any)

        

<0.001

 Yes

370/1149

32.2

136/370

36.8

103/325

27.8

131/325

35.4

 No

779/1149

67.8

400/774

51.7

205/774

26.5

169/774

21.8

Sex worker (all genders)

        

<0.001

 Yes

204/1085

18.8

54/204

26.5

53/204

26.0

97/204

47.6

 No

881/1085

81.2

450/878

51.3

240/878

27.3

188/878

21.4

Female sex worker

        

<0.001

 Yes

155/1085

14.3

32/155

20.7

43/155

27.7

80/155

51.6

 No

930/1085

85.7

472/927

50.9

250/927

27.0

205/927

22.1

Male sex worker

        

0.239

 Yes

48/1085

4.4

22/48

45.8

9/48

18.8

17/48

35.4

 No

1037/1085

95.6

482/1034

46.6

284/1034

27.5

268/1034

25.9

Men who have sex with men

        

0.923

 Yes

174/1149

15.1

80/174

46.0

49/174

28.2

45/174

25.9

 No

975/1149

84.9

456/970

47.0

259/970

26.7

255/970

26.3

People who inject drugs

        

0.184

 Yes

42/1131

3.7

25/42

59.5

7/42

16.7

10/42

23.8

 No

1089/1131

96.3

500/1084

46.1

297/1084

27.4

287/1084

26.5

Transgender women

        

0.242

 Yes

20/1048

1.7

11/20

55.0

7/20

35.0

2/20

10.0

 No

1128/1148

98.3

525/1123

46.8

300/1123

26.7

298/1123

26.5

aNot mutually exclusive

Among participants in Dakar, 42.2% (227/538) were first-time testers, and in Ziguinchor 52.6% (306/582) were first-time testers (Table 4). Among participants 18 to 24 years old, 62.8% (179/285) were first-time testers. Among participants ages 25–30, 46.0% (169/367) were first-time testers, and 38.0% (171/444) were first-time testers among those 31 years and older. Among participants assigned female sex at birth, 38.6% (233/604) were first-time testers compared to 56.2% (303/539) of participants assigned male sex at birth.
Table 4

Demographic characteristics, HIV testing history, motivation for HIV test use and associations with first-time testers in Senegal

Characteristics

Total

HIV testing history

X2 p value

OR

aOR*

95% CI

P value

First-time tester

Individuals with testing history

n/N

%

n/N

%

n/N

%

Region

      

0.001

    

 Dakar

539/1125

47.9

227/538

42.2

311/538

57.8

 

Ref

Ref

  

 Ziguinchor

586/1125

52.1

306/582

52.6

276/582

47.4

 

1.52

1.99

1.53,2.59

<0.001

Age

      

<0.001

    

 18–24

286/1130

25.3

179/285

62.8

106/285

37.2

 

2.75

2.84

2.07,3.90

<0.001

 25–30

370/1130

32.7

169/367

46.0

198/367

54.0

 

1.39

1.32

1.00,1.76

0.063

 31+

474/1130

42.0

171/444

38.0

293/473

62.0

 

Ref

Ref

  

Sex at birth

      

<0.001

    

 Female

607/1148

52.9

233/604

38.6

371/604

61.4

 

Ref

Ref

  

 Male

541/1148

47.1

303/539

56.2

236/539

43.8

 

2.04

2.71

2.08,3.52

<0.001

HIV testing history

n/N

%

n/N

%

n/N

%

P value

OR

aOR**

95% CI

P value

Who suggested you get an HIV test?

      

0.056

    

 Sexual partner

66/1134

5.8

42/66

63.6

24/66

36.6

 

2.13

1.92

1.06, 3.49

0.032

 Peer educator

359/1134

31.7

164/357

45.9

193/357

54.1

 

1.03

1.09

0.76, 1.54

0.648

 Doctor

226/1134

19.9

101/224

45.1

123/206

54.9

 

1.00

1.01

0.68, 1.49

0.979

 Family member

22/1134

1.9

14/22

63.6

8/22

36.4

 

2.13

2.61

1.01, 6.69

0.047

 Friend

213/1134

18.7

97/213

45.5

116/213

54.5

 

1.01

0.95

0.63, 1.42

0.793

 Other

248/1134

21.9

112/248

45.2

136/248

54.8

 

Ref

Ref

  

In the last 12 months, worried about HIV

      

0.065

    

 Yes

837/1053

79.5

368/834

44.1

466/834

55.9

 

0.75

0.68

0.49, 0.94

0.021

 No

216/1053

19.6

110/215

51.2

105/215

48.8

 

Ref

   

Main reason for doing the HIVST today

      

<0.001

    

 Engaged in risky behavior

402/961

41.8

156/401

38.9

245/401

61.1

 

3.74

4.11

2.46.6.86

<0.001

 Sex partner engaged in risky behavior

71/961

7.4

48/71

67.6

23/71

32.4

 

12.26

10.92

5.38, 22.17

<0.001

 Had sex with someone knew/thought to be living with HIV

45/961

4.7

27/45

60.0

18/45

40.0

 

8.81

8.16

3.70, 17.98

<0.001

 Condom broke or slipped

67/961

7.0

47/66

71.2

19/66

28.8

 

14.53

12.70

6.09, 26.51

<0.001

 Someone suggested I get tested

199/961

20.7

116/197

58.9

81/197

41.1

 

8.41

9.32

5.33, 16.28

<0.001

 Part of my regular testing pattern

165/961

17.2

24/165

14.6

141/165

85.5

 

Ref

Ref

  

 Other

12/840

1.3

5/12

41.7

7/12

58.3

 

4.20

1.28

0.24, 6.96

0.776

*adjusted for other demographic characteristics presented in this table

**adjusted for age, sex, and region

Demographic Characteristics, HIV Testing History and HIV Risk Behaviors, and Associations with First-Time Testers

When adjusting for sex and age, region was associated with HIV testing history, with an increased odds of being a first-time tester in Ziguinchor (aOR: 1.99; 95%CI: 1.53, 2.59; p value: < 0.001) compared to Dakar (Table 4). Age was associated with HIV testing history with an increased odds of being a first-time tester among those 18 to 24 years old compared to 31 + (aOR: 2.84; 95CI %: 2.07, 3.90; p-value: < 0.001). Participants assigned male sex at birth had an increased odds of being a first-time tester compared to those assigned female sex (aOR: 2.71; 95CI %: 2.08, 3.52; p-value: < 0.001).

Among pre-test participants, 79.5% (837/1053) had been worried about their HIV status, which was negatively associated with being a first-time tester (aOR: 0.68; 95%CI: 0.49, 0.94; p-value: 0.021) (Table 4). A sexual partner (aOR: 1.92; 95%CI: 1.06, 3.49; p-value: 0.032) or a family member (aOR: 2.61; 95%CI: 1.01, 6.69; p-value: 0.047) suggesting getting tested for HIV were associated with reaching first-time testers compared to ‘other’ people suggesting. The reported primary reason for doing the HIV test was engagement in risky behavior (41.8%; 402/961), sexual partner engagement in risk behavior (7.4%; 71/961), had sex with someone who they thought or knew to be living with HIV (4.7%;45/961), condom failure (7.0%; 67/961), someone suggested to get tested (20.7%; 199/961), and part of a regular testing routine (17.2%; 165/961).

Use of HIVST

Among post-test survey respondents, 94.3% (768/814) reported using the HIVST of which 43.5% (333/765) were first-time testers (Table 5). In total, 54.3% (363/668) used the HIVST at the distribution site and 45.7% (305/668) used the HIVST at home; and 88.9% (595/669) used the HIVST within 2 days. Among those who used the HIVST, 2.9% (19/651) reported a reactive result, and 2.0% (13/651) had an invalid result. Self-reported reactivity was associated with first-time testers (p = 0.024), and among those with a reactive result 63.2% (12/19) were first-time testers. Reported location of receiving the HIVST was associated with HIV testing history (p-value: < 0.001). Overall 10.3% (48/466) of those who reporting using the HIVST reported seeking follow up testing.
Table 5

Use and acceptability of HIVST and differences between first-time testers and individuals with HIV testing history in Senegal

 

Total

First time testers

Individuals with testing history

 

HIVST distribution and use

n/N

%

n/N

%

n/N

%

P value

Reported use of HIVST

      

0.390

 Yes

768/814

94.3

333/765

43.5

432/765

56.5

 No

46/814

5.7

23/46

50.0

23/64

50.0

Place of HIVST use

      

0.092

 Home

305/668

45.7

147/302

48.7

155/302

51.3

 At distribution site

363/668

54.3

153/363

42.2

210/363

57.9

Time of use after distribution

      

0.617

 < 2 days

595/669

88.9

266/593

44.9

327/593

55.1

 > 2 days

74/669

11.1

35/73

48.0

38/73

52.1

Where did you receive your HIV self-test?

      

<0.001

 Hospital

260/742

35.0

130/259

50.2

129/259

49.8

 Community organization

78/742

10.5

24/78

30.8

54/78

69.2

 At a hotspot, bar, or community venue

194/742

26.2

95/192

49.5

97/192

50.5

 Mobile clinic

108/742

14.6

13/108

12.0

95/108

88.0

 Friend or family

102/742

13.8

69/102

67.7

33/102

32.4

Self-reported result of HIVST

      

0.024

 Negative

619/651

95.1

268/619

43.4

349/617

56.6

 Reactive

19/651

2.9

12/19

63.2

7/19

36.8

 Invalid

13/651

2.0

9/12

75.0

3/12

25.0

Confirmed results of HIVST results

      

0.625

 Yes

48/466

10.3

21/48

43.8

27/48

56.3

 No

418/466

89.7

197/415

47.5

218/415

52.5

Acceptability of HIVST

How comfortable did you feel using the HIVST?

      

<0.001

 Comfortable

496/666

74.5

202/494

40.9

292/492

59.1

 Not comfortable

170/666

25.5

96/169

56.8

73/169

43.2

How did you find the instructions?

      

0.427

 Easy

576/669

86.1

263/575

45.7

312/575

54.3

 Not easy

93/669

13.9

38/92

41.3

54/92

58.7

Would you recommend self-testing to others?

      

0.390

 Yes

596/626

95.2

259/594

43.6

335/594

56.4

 No

30/626

4.8

15/29

51.7

14/29

48.3

Do you think your friends and/or family would use an HIVST?

      

0.591

 Yes

638/676

94.4

273/636

42.9

363/636

57.1

 No

38/676

5.6

18/38

47.4

20/38

52.6

Since you receive the HIVST, did you discuss HIV testing with any sexual partners or friends?

      

0.582

 Yes

244/797

30.6

104/244

42.6

140/244

57.4

 No

553/797

69.4

246/550

44.7

304/550

55.3

Would you be comfortable asking your primary sexual partner to use an HIVST?

      

0.037

 Yes

307/391

78.5

132/306

43.1

174/306

56.8

 No

84/391

21.5

47/84

56.0

37/84

44.1

Would you be comfortable asking a casual sexual partner to use an HIVST?

      

0.218

 Yes

150/228

65.8

72/149

48.3

77/149

51.7

 No

78/228

34.2

31/78

39.7

47/78

60.3

Acceptability of HIVST

Overall, 74.5% (496/666) participants reported being comfortable using the HIVST. In total, 86.1% (576/669) found the instructions easy to follow, and 94.4% (638/676) thought their family of friends would use the HIVST. After receiving the HIVST, 30.6% (244/797) discussed HIV testing with a sexual partner or friend. Among participants 78.5% (307/391) would be comfortable asking a primary sexual partner to use an HIVST, and 65.8% (150/228) would be comfortable asking a casual sexual partner to use an HIVST.

HIVST Reactivity

Among post-test respondents reporting a reactive result, 42.1% (8/19) used the test on site, and 57.9% (11/19) used the HIVST at home (Table 6). Among those with a reactive HIVST, 57.9% (11/19) went for confirmatory testing and among those with an invalid test result none went for follow up testing. Among those with a reactive HIVST result, 84.2% (16/19) were male, 31.6% (6/19) were 18–24 years old, and 42.1% (8/19) were a self-reported member of a key population. Among HIVST kits collected at the distribution site, 5.4% (76/1407) had a positive reactivity (Table 1).
Table 6

HIVST result reactivity and association with use and demographic characteristics

 

Reactive (N = 19)

Invalid (N = 13)

Not reactive (N = 619)

X2 P value

 

n/N

%

n/N

%

n/N

%

 

Place of HIVST use

      

0.002

 Home

11/19

57.9

12/13

92.3

274/616

44.5

 At distribution site

8/19

42.1

1/13

7.7

3412/616

55.5

Confirmed results of HIVST results

      

<0.001

 Yes

11/19

57.9

0/11

0.0

37/423

8.8

 No

8/19

42.1

11/11

100.0

386/423

91.4

Sex

      

<0.001

 Female

3/19

15.8

3/13

23.1

350/619

56.5

 Male

16/19

84.2

10/13

76.9

269/619

43.5

Age

      

0.327

 18–24

6/19

31.6

1/13

7.7

56/610

25.6

 25–30

9/19

47.4

6/13

46.2

210/610

34.4

 31+

4/19

21.1

6/13

46.2

244/610

40.0

Key population

      

0.326

 Yes

8/19

42.1

3/13

23.1

167/619

73.0

 No

11/19

57.9

10/13

76.9

452/619

27.0

Discussion

This study demonstrates that HIVST can effectively engage first-time testers at risk for HIV in Senegal, including key populations, cisgender men, and young adults. Expanding access to HIVST may increase the coverage and frequency of HIV testing and thus have an important role in linking people living with HIV to diagnosis and treatment services and potentially mitigating the HIV epidemic in Senegal. Overall history of HIV testing as well as frequency of testing remains low among key populations, as well as among young adults in their social and sexual networks in Senegal. HIVST result reactivity was associated with first-time testing, and among those who tested with an HIVST, acceptability was high for both first-time testers and those reporting previous HIV testing. However, consistent with some earlier studies, confirmatory testing and linkage to care was a challenge during the implementation of HIVST in Senegal [26, 27].

This study highlights that HIVST was able to reach a large proportion of individuals, and in particular key populations, who had never received an HIV test as well as those who had not tested recently. Notably, approximately half of MSW, MSM, PWID, and transgender women reached through HIVST reported not having tested for HIV. Few programs currently exist to provide tailored health services to PWID and transgender women in Senegal, and this study suggests that HIVST may provide an opportunity for PWID and transgender women to increase uptake of testing in this context [28]. The proportion of first-time testers among FSW was lower, suggesting comparatively higher coverage of HIV testing among FSW than other key populations [18]. Sex work is legal in Senegal but is strictly regulated through a registration process for sex workers which includes requirements for HIV testing [20]. Despite this, frequency of testing among FSW is low compared to the recommended guidelines for HIV testing among key populations. Many FSW are not legally registered for sex work in Senegal, and these data suggest potential barriers to traditional testing approaches within challenging environments [18].

This small scale implementation of HIVST leveraged existing programs and networks working with key populations to distribute HIVST. Despite available services and programs in Senegal, HIVST was able to reach a large proportion of first-time testers in this study. Therefore, HIVST represents a promising new approach to increase coverage and uptake of HIV testing through leveraging current programs. However, adoption and integration of HIVST into existing programs will require a revision of the current HIV testing targets for programs in Senegal. HIVST indicators have been incorporated into the PEPFAR Monitoring, Evaluation, and Reporting (MER 2.0) Indicator Reference Guide representing appropriate indicators for collection in HIV testing programs [29]. Notably, the HIV testing yield for programs may decrease if HIVST are included though there will be a lower cost per test offered [30].

First-time testers were associated with HIVST result reactivity in this study, with the majority of self-reported reactive results being among first-time testers. These findings suggest the potential effectiveness of HIVST in increasing HIV diagnosis among those living with HIV in Senegal and not accessing traditional testing services. Additionally, acceptability was overall high among individuals who participated in the post-test survey, as shown in other settings [16, 31, 32]. However, one quarter of participants reported that they were not comfortable using the HIVST, which highlights the need to better understand how to improve comfort during testing. Use and acceptability of HIVST was overall not significantly different between first-time testers and those with a testing history for most measures in this study. These results suggest potential for sustained uptake among both new and returning users. Contrarily, other studies have found that acceptability was influenced by prior HIV testing [33].

Although acceptability of HIVST has been high in other studies, consistent evidence on confirmatory testing and linkage to care similarly remain sub-optimal [26, 27]. In this study, confirmatory testing was low, with approximately two-thirds of those with reactive results, and none with invalid results reporting confirmatory testing. A recent study in Zambia found that individuals who had not previously tested for HIV were negatively associated with intention to linkage to care after HIVST [33]. Therefore, there is a need to better understand implementation strategies for linkage to care, especially for first-time testers. Preferred methods for follow up have varied across studies [33, 34]. Community-based confirmation testing was preferred to facility-based testing in Zambia and Malawi [35]. Some studies have shown success in linkage to care through active follow up, however another study found active support for linkage was less important to individuals than other attributes of confirmation testing locations [35]. HIVST strategies in Senegal may require more active mechanisms for follow up and support to improve linkage to confirmatory testing and care. Notably, young adults in this study had a higher odds of being first-time testers, suggesting traditional testing services are not currently reaching this group in Senegal. HIV incidence among adolescents and young adults is high globally, however uptake of HIV services is low [36]. In particular, HIV incidence is generally highest among young MSM in countries with age-disaggregated incidence data [37, 38, 39]. The emergence of social media and technology to engage young adults and though social and sexual networks may provide an avenue for increasing uptake of HIV testing services for these populations [40]. Mobile phone apps have also been shown to be acceptable among young MSM in other settings and have been used to assess risk and coordinate HIVST distribution [41, 42, 43]. HIVST web-based delivery has been acceptable across settings, including sub-Saharan Africa, and may provide further opportunity to increase uptake and frequency of testing among young MSM [41, 42, 43]. Mobile technology may also be an opportunity to reach individuals in rural areas where program coverage and access to services is less, such as the region of Ziguinchor [44].

Several limitations should be considered in this study. Participation in the pre- and post-test questionnaires was voluntary and may not represent the full sample of individuals who participated in HIVST distribution. The results may therefore be subject to bias. Participants who received HIVST through network distribution were not captured in data collection and are not represented in this analysis. Disclosure of key population status as well as positive reactivity from the HIVST were low in self-reported measures of this study. The distribution strategy prioritized members of key populations and worked closely with existing programs providing services to these populations. However, only one-third of the study sample self-reported key population status. Therefore, it may be that HIVST reached individuals who may not currently be at high risk of HIV, in which case there is a need to consider strategies to more effectively target key populations. Alternatively, key population status may have been underreported, in which case HIVST was able to reach individuals unwilling to disclose their key population-related behavior and less integrated into the key population networks [45]. Additionally, there was a discrepancy between the proportion of reactive HIVST collected at the distribution sites and those who self-reported reactive results during posttest questionnaire. Although these figures cannot be linked or compared directly, it may suggest either underreporting of reactive test results, or possibly greater loss to follow up for posttest questionnaire among individuals with a reactive HIVST.

Conclusions

In Senegal, key populations bear a disproportionate burden of HIV, and report limited uptake of existing HIV testing services given pervasive stigma and criminalization. In these contexts, HIVST may represent a complementary approach to reach populations reporting barriers to engagement with existing and routine HIV testing services. These data suggest the potential impact that HIVST could have in complementing existing HIV testing services by reaching a diverse group of first-time HIV-testers as well as those who have not tested recently in Senegal. This small-scale implementation further suggested the importance of leveraging existing structures and programs for distribution. Moreover, since HIVST has the potential to disrupt traditional testing approaches, sustained engagement with government and community stakeholders is needed to inform optimal implementation strategies of HIVST.

Notes

Acknowledgements

We would like to thank the study participants for donating their time to contribute to this research. Thank you to the study staff, partners, and government support for making this study possible. Thank you to Amrita Rao for support throughout study implementation and manuscript development. Thank you to Maria Garcia Quesada and Pedro Saa for supporting translation. Thank you to Johns Hopkins University Center for AIDS Research (P30AI094189). This study was made possible by the generous support of the American people through the U.S. President’s Emergency Plan for AIDS Relief (PEPFAR) with the U.S. Agency for International Development (USAID) under the Cooperative Agreement Project SOAR (Supporting Operational AIDS Research), number AID-OAA-14-00060. The information provided does not necessarily reflect the views of USAID or the United States Government, and the contents of this manuscript are the sole responsibility of Project SOAR, the Population Council, and the authors.

Compliance with Ethical Standards

Conflict of interest

The authors declares that they have no conflicts of interest.

Ethical Approval

Ethical review and approval were provided by the National Research Ethics Committee in Senegal and the Johns Hopkins School of Public Health Institutional Review Board.

Informed Consent

Informed consent was obtained from all individual participants included in the study.

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© The Author(s) 2019

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Authors and Affiliations

  • Carrie E. Lyons
    • 1
    Email author
  • Karleen Coly
    • 1
  • Anna L. Bowring
    • 1
  • Benjamin Liestman
    • 1
  • Daouda Diouf
    • 2
  • Vincent J. Wong
    • 3
  • Gnilane Turpin
    • 1
  • Delivette Castor
    • 3
  • Penda Dieng
    • 2
  • Oluwasolape Olawore
    • 1
  • Scott Geibel
    • 6
  • Sosthenes Ketende
    • 1
  • Cheikh Ndour
    • 4
  • Safiatou Thiam
    • 5
  • Coumba Touré-Kane
    • 7
  • Stefan D. Baral
    • 1
  1. 1.Department of Epidemiology, Center for Public Health and Human RightsJohns Hopkins School of Public HealthBaltimoreUSA
  2. 2.Enda SanteDakarSenegal
  3. 3.Office of HIV/AIDS, Bureau for Global HealthUSAIDArlingtonUSA
  4. 4.Division de La Lutte Contre Le Sida et Les ISTMinistry of HealthDakarSenegal
  5. 5.Conseil National de Lutte contre le SidaDakarSenegal
  6. 6.Population CouncilWashingtonUSA
  7. 7.Laboratoire de Bacteriologie-VirologieCHU Aristide Le DantecDakarSenegal

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