Creating a Sexually Transmitted Infection Disease Intervention Workforce for the 21st Century

Recent and sustained increases in sexually transmitted infections (STIs)¹ and the severe acute respiratory syndrome coronavirus 2 pandemic² have accelerated technological advances for disease intervention and brought new attention to communicable disease.³ These events provide an opportunity for public health to reflect on the role of disease intervention in curbing infectious disease transmission and focus on methods to enhance and expand existing disease intervention functions. In addition, substantial federal investment in disease intervention activities makes this an opportune time to develop a more robust and nimble disease intervention workforce.⁴ Disease intervention includes traditional functions, such as case investigation and contract tracing (CICT; also referred to as partner services), and has been in practice for numerous decades for the control and prevention of infectious diseases such as STI.⁵ In most instances, the primary focus of disease intervention is to reduce or halt transmission of infections. Within STI prevention, the disease intervention role is often conducted by disease intervention specialists (DISs) or communicable disease investigators (referred to as DIS hereafter).⁶ We propose a model that describes activities conducted by DIS and how these activities can be impacted by public health priorities and the context surrounding their work (Fig. 1). We will discuss how DIS activities and the various contextual factors we highlight can influence or impact each other.

Figure 1.

Disease investigation activities: context and interactions. CM, case management.

DISEASE INTERVENTION ACTIVITIES

Depending on the jurisdiction, DIS can conduct a myriad of functions and activities.⁶ For STI prevention, disease intervention activities historically include what is commonly referred to as partner services (e.g., outreach staff notify sex partners of potential exposure with the aim to provide testing and treatment).⁷ Partner services remain an important component of syphilis prevention efforts in the United States.⁸ Research has indicated that having DIS located in clinics that serve populations at increased risk for STI can result in more timely interviews of index patients and an improved documented treatment rate for their contacts.⁹

As shown in our model, STI disease intervention consists of more than partner services (Fig. 1). Disease intervention specialists often collect important surveillance data on STI cases that aid in the understanding of the current epidemiology of various STIs.¹⁰ Sexually transmitted infection disease intervention also provides an opportunity to offer HIV services to those at increased risk including HIV field testing of STI contacts and linkage to HIV care for contacts with positive HIV tests.¹¹ Disease intervention specialists can also link contacts to HIV preexposure prophylaxis (PrEP) services. An evaluation of a partner services program implemented by a health department showed that PrEP initiation was highest among men who have sex with men (MSM) at highest risk for HIV.¹² Sexually transmitted infection disease intervention work may also incorporate additional referral or linkage programs for sexual health, mental health, and substance abuse services.⁶ Furthermore, in most local and state health departments, DISs engage in outbreak response and responses to other public health emergencies.⁶

Public health priorities, including performance metrics, also impact DIS efforts (Fig. 1). For example, a study of 6 states in New England found that implementation of partner services differed by public health priorities, such as funding for staff and laboratories, and which STIs were a priority in the jurisdiction.¹³ Furthermore, organization of partner services varies by state. A survey found that partner services can be conducted at the state and/or local level and STI partner services can be separate or integrated with HIV or across all communicable diseases.⁶ Performance metrics have been historically used to evaluate partner services efforts related to contact tracing; however, a study focusing on partner services for early syphilis in several jurisdictions estimated that about 80% of sex partners were not reported.¹⁴ This estimate of unreported partners is higher than findings from an assessment of partner services provided to MSM with gonorrhea or chlamydia in King County, WA, where 39% of partners were unreported.¹⁵ The extent to which partner services are effective may reflect the specific STI evaluated, differences in partner services programs studied, or changes in the nation's sexual culture (e.g., meeting partners online) is uncertain. In part, this has prompted proposals to expand the goals of partner services beyond partner notification (e.g., HIV testing and linkage to various healthcare services).⁷

CONTEXT OF DISEASE INTERVENTION ACTIVITIES

Activities conducted by DIS can be influenced by the context surrounding their work, such as existing regulations; organizational structure; human interaction and community engagement; and changes in data management, testing, treatment, and prevention technologies (Fig. 1). Regarding regulations and their influence on disease intervention, a 1996 analysis of state laws found that the majority of states had public health information protection for STI data; nevertheless, most of those states allowed disclosure of information for notification or contact tracing purposes.¹⁶ Accordingly, in a 2016 survey, all but one state reported having a DIS workforce for STI/HIV.¹⁷ However, 61% of states reported that the number of DIS that they have is not sufficient for this work.¹⁷ Insufficient DIS staff coupled with an expansion of disease intervention activities suggest that it may be useful to assess the organization of DIS to ensure that they can meet the needs of STI prevention.⁷ Furthermore, the lack of research focusing on the human interaction components of disease intervention activities and community engagement with these activities indicates that it may also be time to assess the best ways to communicate with and motivate people, and the best methods to increase community engagement could improve disease intervention outcomes.

Technological advances in data management and related technology can aid in CICT and STI partner services. For example, electronic laboratory reporting increased the timeliness of reported positive STI test result, and automated triaging of cases can improve program efficiency.^18,19 In addition, research has been evaluating the use of electronic health records for case reporting to provide more complete demographic and other data than electronic laboratory reporting typically provides.²⁰ Technology such as smartphone applications (apps) have also been used to assist DIS with interviews by providing a tool to immediately identify sex partners who were found on dating or hook-up apps and Web sites.²¹

The severe acute respiratory syndrome coronavirus 2 pandemic hastened technological advances that could more quickly alert someone who had exposure to the virus and report cases to health departments. In response to the pandemic, the Google Apple Exposure Notification (GAEN) app was quickly developed to aid in CICT.²² GAEN used Bluetooth technology to assess the duration of time 2 smartphones were in close proximity and send alerts to persons who were in close contact with someone who tested positive for COVID-19.²² To date, research has been mixed on how effective and useful such technology could be^23–26; nevertheless, new technology can lead to related advances that would potentially be useful for STI disease intervention efforts. The pandemic also accelerated technology focusing on data management systems. An assessment of CICT tools used in the United States and US territories found a variety of tools were adapted to aid in quicker case notification and in case management.³ Some data suggest that CICT efforts for COVID-19 likely averted cases and aided in curbing transmission.² Some of these approaches may be adapted for STI disease intervention activities.

Advances in medical and prevention technologies have also been used in STI prevention that could be useful to disease investigation activities. Recent research has shown how automated screening based on sexual history taking and self-collection of extragenital swabs can aid in identification of additional STIs among persons living with HIV.²⁷ Self collection of swabs was also acceptable and was chosen by 62% of participants who were identified for this screening.²⁷ Advances in rapid test technology²⁸ along with self-collection of specimens could potentially be used as part of disease investigation efforts. Advances in diagnostics, including molecular and rapid tests, accelerated at an extraordinary pace during the COVID-19 pandemic.²⁹

After minimal uptake over the years, advances in telehealth, or remote health care, started at the beginning of the century.³⁰ Telehealth adoption has grown and has included sexual health and STI. For instance, one study used telehealth via video conferencing to show MSM how to collect specimens and then to deliver STI test results to the participants.³¹ The COVID-19 pandemic accelerated the use of telehealth with a more flexible regulatory and reimbursement environment.³² Although it may not yet be known how much of the flexibility around telehealth may remain after the pandemic, its use likely could be helpful for STI disease intervention activities.

ARTICLES IN THIS ISSUE

This supplement is meant to provide essential information and noteworthy advances for areas of importance in enhancing disease intervention functions. The supplement includes articles focusing on the center of our disease intervention figure, including effectiveness and the impact of disease intervention functions. Other articles focus on the context that surrounds and interacts with disease intervention functions and effectiveness.

Evidence in support of CICT has been mixed with a possible decline in effectiveness for STI/HIV and a lack of evaluation via randomized controlled trials; however, research suggests that assisted partner services (i.e., when health department staff assist with notifying contacts) may be useful for HIV and syphilis outbreaks as well as delivery of some HIV services.³³ The interplay between factors associated with CICT components (case investigation, contract tracing, and case management) and factors associated with specific STI is important.³³ Disease intervention can be adapted to include new technology depending on the incubation period for the disease and volume of cases and can use a health equity approach by focusing on areas with high prevalence.³⁴ Evaluations also demonstrate how diverse expertise is needed because DISs not only investigate disease but also must be responsive to diverse issues such as mental health conditions and socioeconomic concerns.³⁴

Disease intervention activities can be evaluated using performance metrics, outcome assessments, and cost-effectiveness analyses. Over time, there has been little change in the performance measures, including process and clinical measures, used to assess disease intervention activities.³⁵ In addition, measures may not include what was missed by syphilis partner service interviews (e.g., unnamed partners, partners not reached, partners treated without DIS contact), and many DIS activities are not included in existing metrics.³⁵ Another method to assess the impact of DIS work is through cost-effectiveness analyses, which can aid in a prioritization of disease intervention activities.³⁶

As previously noted, various contextual factors that are often interconnected can impact disease intervention activities, and this relationship is often bidirectional. A recent analysis of state law found that states authorize or require disease investigation for communicable disease or sexually STIs to varying degrees.³⁷ In addition, funding accountability is important because public programs use taxpayer dollars and must prioritize public trust and confidence and is central to improving equitable access to public services.³⁸ Another factor that can impact disease intervention activities is workforce retention. A cost-effectiveness evaluation assessed different changes in hiring and training (e.g., pay increase, mentoring program), and they had different impacts on DIS workforce retention.³⁹ Open source software could also impact disease intervention because it is publicly accessible and support can be provided by the community of users; however, challenges to adoption include difficulties integrating with existing systems and whether significant customization is needed for a given user.⁴⁰ Infrastructure that allows very quick synthesis of data from multiple databases to provide both timely and complete case report data is important, and several products are now available.⁴¹ An example from Maryland shows how receipt of timely and improved case report data can assist in successful contact tracing efforts.⁴²

Disease intervention specialists can often conduct field-based specimen collection, testing, and treatment depending on the jurisdiction, and the increased use of telehealth during COVID-19 has the potential to significantly expand the DIS role into longer-term therapy.⁴³ However, the extent of the DIS role in this area will be determined by local and state regulations and licensing restrictions.⁴³ A field services home-based program in New York that seems to be promising included a telehealth visit with a nurse practitioner as well as self-collected STI testing, field delivery of STI and HIV treatment and PrEP, and expedited clinic visits for follow-up HIV testing.⁴⁴ Finally, newer developments in testing technology may have a significant impact on disease intervention including advancements in rapid tests, point-of-care tests, and self-collection of specimens.⁴⁵ This technology is important because it can aid in field-based activities as well as rapid identification of infections to allow more timely treatment to halt disease transmission.⁴⁵

FUTURE RESEARCH

Although there are many ways that disease intervention activities have been expanded and enhanced, future research can also focus on additional areas to improve disease intervention for STI (Table 1). Better designed and controlled research studies are needed to determine the effectiveness of some disease intervention activities. Mathematical modeling of the role of various disease intervention activities could suggest which intervention activities delivered by which kinds of health providers would optimize effectiveness and cost-effectiveness in a context of health provider scarcity. Various metrics are used to assess disease intervention; however, we have not identified an “ideal set” of performance metrics for those who implement these activities. In addition, we currently lack information on how some disease intervention activities impact population-level disease rates. Although the latter may be difficult to assess, public health's focus on population health is an important consideration for disease intervention activities. Furthermore, numerous disease intervention activities have been proposed or are in practice, and it simply is not possible to implement all new functions for all STI in all areas. It is imperative that research aid in demonstrating the disease intervention activities that are the most effective and are cost-effective. Finally, community engagement in disease intervention efforts may be helpful to gain the trust and insights of communities to further the effectiveness of public health efforts.

TABLE 1.

Research Needed to Inform STI Disease Intervention Efforts

Area of Focus	Research Question
DI Activities
Effectiveness	Which DI activities are most effective and most cost-effective for STI?
	Which DI activities delivered by which kinds of health providers would optimize effectiveness and cost-effectiveness in a context of health provider scarcity?
Public health activities	What are the best ways to engage communities in updating and expanding DI efforts?
Performance metrics	What is the “ideal set” of performance measures?
	What is the impact of DI activities on population disease rates?
Context
Regulatory context	What informal processes and policies in health departments guide DI activities and efforts?
	What regulatory changes are needed to implement medical technological advances that could shift some activities from doctors and nurses to DIS?
Accountability	What are the best measures for accountability of public funding?
Organizational structure	What is best organizational structure for DI activities?
Workforce	What is the best method to retain employees? To reduce turnover?
Technological advances	What considerations are given to user interface for new digital technology? How easily can new technology be integrated with existing systems? How easily are data extracted?
	What are the privacy issues related to a new technology? How does a lack of trust in government or big business influence uptake and use of new technology?
	What technology is acceptable to which subpopulations under what circumstances?
	Who are we missing when we use a specific technology? What is the impact on health inequities?
	What policy changes are needed to maximize impact of new medical technology?
	For new technology, what STIs should be targeted, what training needs disease intervention staff will have, and whether delivering some technology will be acceptable to disease intervention?

DI indicates disease intervention.

Research can also help to address various contextual factors and how they may impact disease intervention. Although some legislation, particularly at the state level, focuses on disease intervention activities, we lack information on the informal processes and policies that may really guide this work. Changes in regulations may also be needed for DIS to implement some of the medical technological advances that could shift some activities from doctors and nurses to DIS. In addition, multiple approaches to accountability exist; however, we need information to determine the best measures of accountability. Furthermore, it may be helpful for researchers and others who specialize in organizations to consider the optimal organizational structure for disease intervention activities and the staff who conduct them. Research could aid in determining how structure may impact disease intervention functions and influence population health outcomes. More research is also needed to address workforce retention issues and optimal strategies to reduce turnover.

As previously described, advances in digital and medical technology can greatly impact disease intervention activities; however, they have some limitations that future research could help address. The user interface for digital technology and the ease with which a system can be changed and data extracted are important to adoption of the technology. For some digital tools, privacy is a key consideration. Some people are less likely to trust government and big businesses, and it is vital to assess how this lack of trust can influence uptake and use of this technology. Research can aid in determining what technology is acceptable to which subpopulations under what circumstances. Adoption of digital technology may vary by population and by jurisdictions. When using digital technology, an important question to ask ourselves is who are we missing? Our efforts should not worsen health inequities. Finally, medical technology can also meaningfully advance disease intervention activities. However, these advances may require changes in policies and licensing to maximize their impact. Research can aid us in defining what STIs should be targeted, what training needs disease intervention staff will have, and whether delivering some technology will be acceptable to disease intervention staff.

In conclusion, the articles in this supplement show that disease intervention staff are required to serve in very diverse roles. Although current helpful trainings exist, trainings on topics such as “soft skills,” which include personal attributes that help us work well with others (e.g., communication, listening, adaptability), and refresher trainings are needed. Community engagement may also increase the acceptability and effectiveness of disease intervention activities. Delivery of all the various disease intervention activities for all STI is not realistic, and which activities to adopt may depend on the unique circumstances of jurisdictions and their local STI epidemic. The COVID-19 pandemic has provided us with new technologies that may be useful complements to DIS work. However, data could help to show what works best, with what population, and in what circumstance. We are hopeful that researchers will prioritize key disease intervention activities to provide additional data on the effectiveness of various activities and tools in specific subpopulations.