ABC of Sexually Transmitted Infections

Karen E. Rogstad

• Publisher: BMJ Books
• Year: 2011
• Print ISBN: 9781405198165
• eBook ISBN: 9781118251188
• Edition: 6
• Topic: Medicine
• Subtopic: Diseases & Allergies

With sexually transmitted infections (STIs) a major cause of morbidity and mortality throughout the world, the new edition of ABC of Sexually Transmitted Infections is a much-needed introduction and reference guide providing concise and practical information on a range of conditions.

This sixth edition includes the latest guidance on the prevalence, prevention and treatment of STIs, screening programmes and new testing methods. It features new chapters on service modernisation and new care providers, high risk and special needs groups, the use of the internet for information and education, systemic manifestations and sexually transmitted infections in resource-poor settings. Contraception is also covered, reflecting the increasing integration of STI and contraceptive services.

With an international authorship, the ABC of Sexually Transmitted Infections is an authoritative guide and reference for all practitioners, especially those providing community based STI diagnosis and management such as GPs, primary care physicians and contraceptive service providers. Junior doctors, medical students, and nurses working in community or specialist services will also find it a valuable resource as will those working in the fields of obstetrics and gynaecology and public health. This new edition also provides information useful for new STI care providers such as pharmacists, those in the voluntary sector and providers of STI services in resource-poor settings.

CHAPTER 1

Sexually Transmitted Infections: Why are they Important?

Kevin A Fenton¹and Karen E Rogstad²

¹Centers for Disease Control and Prevention, Atlanta, USA

²Department of Sexual Health and HIV, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, UK

OVERVIEW

• There are more than 30 different sexually transmissible bacteria, viruses and parasites
• A million people acquire HIV or another STI every day
• There are 33.4 million people with HIV worldwide, with 2.7 million new HIV infections and 2 million HIV-related deaths annually (1998 data)
• STIs (excluding HIV) are the second most common cause of healthy life lost in 15- to 44-year-old women
• STIs cost $16 billion annually to the health care system
• Preventing a single HIV transmission would save £0.5–1 million in health benefits and costs

What are sexually transmitted infections?

Sexually transmitted infections (STIs) are infections that are spread primarily through person-to-person sexual contact. There are more than 30 different sexually transmissible bacteria, viruses, and parasites (Table 1.1). Several, in particular HIV and syphilis, can also be transmitted from mother to child during pregnancy and childbirth, and through blood products and tissue transfer.

In general, the viral STIs (including sexually transmitted HIV and hepatitis A, B, and C) are more prevalent, often causing lifelong infections, frequently asymptomatic in their early phases, and may result in serious long-term sequelae including chronic morbidity or even mortality. In contrast, the bacterial and protozoal STIs are generally curable, and often asymptomatic. The causative organisms may cause a spectrum of genitourinary symptoms, including urethral discharge, genital ulceration, and vaginal discharge with or without vulval irritation.

STIs are among the most commonly diagnosed infectious diseases in many parts of the world. More than a million people acquire HIV or another STI every day, and there are 450 million new cases of curable STIs occurring in adults each year. There is marked variation in the prevalence and incidence of infections throughout the world, and even within countries (Figure 1.1 and Table 1.2).

Why are STIs important?

Being diagnosed with an STI can have a tremendous physical, emotional, and psychological toll on individuals. Symptoms are unpleasant and may cause considerable pain, and have systemic complications. HIV and hepatitis B and C may have an aggressive course leading to lifelong morbidity and death. Some human papillomavirus (HPV) types are a cause of cervical, penile, anal, and oropharyngeal cancer (Table 1.3). Chlamydia and gonorrhoea are both the most serious, and also most preventable, threats to women’s fertility worldwide. The World Bank estimated that STIs (excluding HIV) were the second most common cause of healthy life lost after maternal morbidity in 15- to 44-year-old women (Figure 1.2).

Effects on pregnancy, neonates, and children

STIs can lead to miscarriage, intrauterine growth retardation, and in utero death. They can also cause neonatal illness and death, and long-term sequelae. The consequences of congenital herpes and HIV are well recognised in developed nations. However, the magnitude of the congenital syphilis burden, globally, rivals that of HIV infection in neonates yet receives little attention. Congenital syphilis results in serious adverse outcomes in up to 80% of cases and is estimated to affect over 1 million pregnancies annually.

Effects on partners

STIs are also important to sexual partners, who may have asymptomatic infection. Partner notification is a key strategy for identifying and treating sexual partners for most STIs (see Chapter 2). The diagnosis of an acute STI may indicate that a partnership is non-monogamous, with negative impacts on relationships. For some couples who are discordant for infections such as HIV or herpes, there are long-term implications such as whether to have unprotected sex and psychological issues.

Stigma

The stigma and fear of STIs cannot be over-emphasised. There is significant psychological morbidity associated with being diagnosed with an STI which ranges from mild distress to severe anxiety and depression. Stigma can result in people living with HIV and other STIs being rejected, shunned, and discriminated against by partners, family, and community, and being victims of physical violence. Stigma not only makes it more difficult for people trying to come to terms with and manage their illness, but it also interferes with attempts to fight the disease more generally. On a national level, stigma can deter governments from taking fast, effective action against STI epidemics.

Table 1.1 Main sexually transmitted pathogens and the diseases they cause.

Source: World Health Organization, 2007.

Pathogen	Clinical manifestations and other associated diseases
	Bacterial infections
Neisseria gonorrhoea	GONORRHOEA Men: urethral discharge (urethritis), epididymitis, orchitis, infertility. Women: cervicitis, endometritis, salpingitis, pelvic inflammatory disease, infertility, preterm rupture of membranes, peri-hepatitis. Both sexes: proctitis, pharyngitis, disseminated gonococcal infection. Neonates: conjunctivitis, corneal scarring and blindness
Chlamydia trachomatis	CHLAMYDIAL INFECTION Men: urethral discharge (urethritis), epididymitis, orchitis, infertility. Women: cervicitis, endometritis, salpingitis, pelvic inflammatory disease, infertility, preterm rupture of membranes, peri-hepatitis; commonly asymptomatic. Both sexes: proctitis, pharyngitis, Reiter’s syndrome. Neonates: conjunctivitis, pneumonia
Chlamydia trachomatis (strains L1–L3)	LYMPHOGRANULOMA VENEREUM Both sexes: u...

Table of contents

• Cover
• Title
• Copyright
• Contributors
• Preface
• CHAPTER 1: Sexually Transmitted Infections: Why are they Important?
• CHAPTER 2: STI Control and Prevention
• CHAPTER 3: Provision and Modernisation of Sexual Health Services
• CHAPTER 4: The Sexual Health Consultation in Primary and Secondary Care
• CHAPTER 5: Examination Techniques and Clinical Sampling
• CHAPTER 6: Main Presentations of Sexually Transmitted Infections in Male Patients
• CHAPTER 7: Other Conditions Affecting the Male Genitalia
• CHAPTER 8: Vaginal Discharge: Causes, Diagnosis, and Treatment
• CHAPTER 9: Pelvic Inflammatory Disease and Pelvic Pain
• CHAPTER 10: Vulval Diseases
• CHAPTER 11: Sexually Transmitted Infections and HIV in Pregnancy
• CHAPTER 12: Genital Ulcer Disease
• CHAPTER 13: Syphilis: Clinical Features, Diagnosis, and Management
• CHAPTER 14: Genital Growths and Infestations
• CHAPTER 15: Viral Hepatitis
• CHAPTER 16: Systemic Manifestations of STIs
• CHAPTER 17: HIV
• CHAPTER 18: Diagnosis of Sexually Transmitted Infections
• CHAPTER 19: Contraception
• CHAPTER 20: Care of Specific Risk Groups
• CHAPTER 21: Sexual Health Care in Resource Poor Settings
• CHAPTER 22: Vaccinations, Treatments, and Postexposure Prophylaxis
• CHAPTER 23: The Internet as a Resource for STI Education and Information
• APPENDICES: Proformas for Taking Sexual Histories
• Index