Infectious diseases are the leading cause of death globally, particularly among children and young adults. The spread of new pathogens and the threat of antimicrobial resistance pose particular challenges in combating these diseases. Major Infectious Diseases identifies feasible, cost-effective packages of interventions and strategies across delivery platforms to prevent and treat HIV/AIDS, other sexually transmitted infections, tuberculosis, malaria, adult febrile illness, viral hepatitis, and neglected tropical diseases. The volume emphasizes the need to effectively address emerging antimicrobial resistance, strengthen health systems, and increase access to care. The attainable goals are to reduce incidence, develop innovative approaches, and optimize existing tools in resource-constrained settings.

One in five people in the United States had a sexually transmitted infection (STI) on any given day in 2018, totaling nearly 68 million estimated infections. STIs are often asymptomatic (especially in women) and are therefore often undiagnosed and unreported. Untreated STIs can have severe health consequences, including chronic pelvic pain, infertility, miscarriage or newborn death, and increased risk of HIV infection, genital and oral cancers, neurological and rheumatological effects. In light of this, the Centers for Disease Control and Prevention, through the National Association of County and City Health Officials, commissioned the National Academies of Sciences, Engineering, and Medicine to convene a committee to examine the prevention and control of sexually transmitted infections in the United States and provide recommendations for action. In 1997, the Institute of Medicine released a report, The Hidden Epidemic: Confronting Sexually Transmitted Diseases. Although significant scientific advances have been made since that time, many of the problems and barriers described in that report persist today; STIs remain an underfunded and comparatively neglected field of public health practice and research. The committee reviewed the current state of STIs in the United States, and the resulting report, Sexually Transmitted Infections: Advancing a Sexual Health Paradigm, provides advice on future public health programs, policy, and research.

In all countries of the European Union and European Economic Area, men who have sex with men (MSM) are disproportionately affected by HIV and other sexually transmitted infections including gonorrhoea, syphilis, chlamydia and hepatitis B and C. In several countries in the region, the incidence of these infections has increased among MSM, in some cases markedly, over the last decade. There is evidence that services to prevent, diagnose and treat infections are not being delivered at the appropriate scale to impact on transmission patterns. Based on a systematic review of the literature and expert opinion, the European Centre for Disease Prevention and Control suggests that there is good evidence to ensure that the following key components are considered for inclusion in national and sub-national public health programmes in countries in Europe.^The evidence indicates that these services and interventions can effectively prevent and reduce HIV and STI transmission among MSM, address the needs of MSM who are living with HIV, as well as promote sexual health among all MSM. 1. Vaccinations: Promote and deliver vaccination to protect against hepatitis A and B. Consider vaccination for human papilloma virus (HPV). 2. Condoms: Provide easily accessible condoms and condom-compatible lubricants and promote their effective use. 3. HIV and STI testing: Provide voluntary and confidential HIV and STI counselling and testing via a variety of modalities that are easy to access for the target group. Voluntary partner referral can support the early diagnosis and treatment of contacts. 4. Treatment: Timely provision of treatment for HIV, viral hepatitis and STI should be ensured. Preventive benefits of treatment are significant. 5.^Health promotion: Provide accurate and accessible information that enables men to understand and assess sexual health-related risks and prevention efficacy, and that promotes awareness of one's own HIV and STI status. 6. MSM-competent health services: MSM-competent points of care offering a comprehensive sexual health programme including health promotion, counselling, peer support, prevention, adequate diagnostics and treatment will increase service uptake. Ensure target group involvement and training for providers on how to offer comprehensive care for MSM. 7. Targeted care for MSM living with HIV: Provide antiretroviral treatment for HIV and vaccination; regular STI screening using adequate diagnostics; treatment for STIs; individual counselling, sexual health promotion and peer-support groups for men living with HIV.^Prevention services for MSM should be targeted following the analysis of relevant and reliable epidemiological data, so that services are directed at the appropriate scale to those geographical and risk populations most at risk of HIV and STI infection. Combinations of the suggested key interventions should be offered to MSM in order to achieve synergy and the highest levels of effectiveness. Prevention needs and preferences of MSM vary across and within country settings, by individual and over time. Offering and implementing prevention packages in collaboration with the target group, or where appropriate, by the target group, is crucial to the success of national and sub-national prevention programmes. As many countries in Europe experience constrained public health budgets, it is more important than ever to implement targeted and evidence-based measures that address the groups most affected by the HIV epidemic as well as those most at-risk for disease acquisition and transmission.^The promotion of sexual health using positive messages framed in an empowering environment in relation to individual needs, will ensure greater effectiveness of the prevention efforts resulting in increased sexual health and reduced new infections of HIV and other STI in Europe.

The term "men who have sex with men" - frequently shortened to MSM - describes a behaviour rather than a specific group of people. It includes self-identified gay, bisexual, transgendered or heterosexual men. Many men who have sex with men do not consider themselves gay or bisexual. They are often married, particularly where discriminatory laws or social stigma of male sexual relations exist. Largely because of the taboo, the female partners of men who have sex with men are often unaware of their partner's other liaisons, and the threat posed to themselves. Forced sex among men is not uncommon, especially in men-only environments such as prisons. Men who have sex with men are found in all societies, yet are largely invisible in many places. In terms of HIV, sex between men is significant because it can involve anal sex, which when unprotected carries a very high risk. Sex between men is thought to account for between 5 and 10% of global HIV infections, although the proportion of cases attributed to this mode of transmission varies considerably between countries. It is the predominant mode in much of the developed world. Globally less than one in twenty men who have sex with men have access to the HIV prevention and care services they need. Many factors contribute to this situation including denial by society and communities, stigma and discrimination, and human rights abuse. Vulnerability to HIV infection is increased where sex between men is criminalised, as men are either excluded from, or exclude themselves from, sexual health and welfare agencies out of fear. A range of interventions to reduce risk behaviours among men who have sex with men have proven successful, including: condom promotion, safer-sex campaigns and skills training; peer education with outreach programmes; and programmes tailored to subpopulations such as male sex workers and men in prisons. Specific policy measures are crucial for making prevention, care and support available to men who have sex with men. First and foremost, they must be included in national HIV programming and funding priorities. The governments must support organisations of men who have sex with men, enabling them to promote HIV prevention and care programmes and to participate in HIV planning and policymaking. Legislation should be changed, decriminalizing same-sex acts and providing protective laws against discrimination based on sexual orientation.

In 2022, WHO published the Consolidated guidelines on HIV, viral hepatitis and STI prevention, diagnosis, treatment and care for key populations. These guidelines outline a public health response to HIV, viral hepatitis and sexually transmitted infections (STIs) for five key populations (men who have sex with men, sex workers, people in prisons and other closed settings, people who inject drugs and trans and gender diverse people). In this policy brief, we give an update on those parts of the guidelines which are relevant for men who have sex with men.