Sexually Transmitted Diseases (STDS)
Causes and Symptoms (Magill’s Medical Guide, Sixth Edition)
Sexually transmitted diseases, or STDs (formerly called venereal diseases), have plagued humankind for centuries. The most prevalent, serious STDs are syphilis, gonorrhea, nongonococcal urethritis, trichomoniasis, genital herpes, genital warts, viral hepatitis, and AIDS. Others, troublesome but not as serious, include lice, scabies, and vaginal yeast infections. They are passed on from one person to another mostly by sexual contact, although some of these diseases may be acquired indirectly through contaminated objects or blood. In addition, nearly all these diseases can be passed on from an infected mother to her fetus, which may cause birth defects, severe and damaging infections, or even death. A person can acquire several STDs at the same time, and since recovery from an STD does not confer immunity, a person can get them again and again. Many of these diseases are asymptomatic, which allows them to spread and cause serious complications before a victim is aware of being infected. Finally, some STDs are treatable and some are not.
Syphilis is caused by Treponema pallidum. This bacterium normally infects the penis in males and the vagina or cervix in females, but it can also enter through a cut on the mouth or other parts of the skin. Once inside, the bacteria grow at the site of entry, then spread throughout the body through the lymph and blood vessels. The symptoms of syphilis are caused by the efforts of...
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Treatment and Therapy (Magill’s Medical Guide, Sixth Edition)
Sexually transmitted diseases can be diagnosed in several ways. One way is by observing the symptoms and case history of the patient. Characteristic sores or symptoms can lead a doctor to suspect a particular disease, and a sample of a scraping from a lesion or an unusual discharge can be examined under a microscope to identify the infecting organism. The syphilis, gonorrhea, chlamydia, and trichomoniasis organisms all have unique shapes that a doctor can recognize. For those STDs with mild symptoms or no symptoms, a doctor can try to grow the organism in the laboratory from samples taken from appropriate sites on the body. All organisms that cause STDs can be grown in the laboratory, and since these organisms are not normally present in humans, isolation of the organism from the body is a sign that the body has been infected by that organism. Finally, there are many blood tests that have been developed to test whether a person has specific antibodies in his or her blood that bind to one of these organisms. The presence of antibodies to an organism implies that one has been or is currently infected with that organism. In many cases, doctors will use several of these methods to confirm a diagnosis of an STD.
Specific treatment recommendations for each sexually transmitted disease are subject to periodic revision. Current recommendations are reviewed by the Centers for Disease Control and are published in the...
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Perspective and Prospects (Magill’s Medical Guide, Sixth Edition)
Syphilis was first recognized at the end of the fifteenth century in Europe, where it rapidly reached epidemic proportions and was called the “great pox.” Gonorrhea was described and given its present name by the Greek physician Galen in 150 c.e. From the fifteenth century to the eighteenth century, there was much confusion as to the nature of syphilis and gonorrhea, and many persons thought they were different stages of the same disease. In 1767, an English physician named John Hunter inoculated himself with a urethral discharge from a patient with gonorrhea in order to determine once and for all whether they were one disease or two. Unfortunately, that patient also had syphilis, so when Hunter developed symptoms of both gonorrhea and syphilis he concluded they were a single disease. It was not until 1838 that it was clearly proved that they were two separate diseases. Traditionally, 95 percent of all cases of sexually transmitted disease were either syphilis or gonorrhea. Since the late twentieth century, however, there has been a dramatic increase in the incidence of several other sexually transmitted diseases, such as genital herpes, NGU, AIDS, genital warts, and trichomoniasis.
The rise in incidence of STDs is of epidemic proportions. Worldwide in the 1990’s, about 250 million new cases of STDs occurred annually. In the United States, about 12 million new cases, including 3 million in teenagers, occurred...
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For Further Information: (Magill’s Medical Guide, Sixth Edition)
Berek, Jonathan S., ed. Berek and Novak’s Gynecology. 14th ed. Philadelphia: Lippincott Williams & Wilkins, 2007. A standard text covering all aspects of gynecology with an emphasis on diagnosis and treatment. Topics include biology and physiology, sexuality, evaluation of pelvic infections, and malignant diseases of the reproductive tract.
Biddle, Wayne. A Field Guide to Germs. 2d ed. New York: Anchor Books, 2002. This comprehensive book is easily accessible to the nonspecialist and includes a discussion of nearly every virus, bacterium, and fungus known to cause human and nonhuman animal disease.
Eng, Thomas Rand, and William T. Butler, eds. The Hidden Epidemic: Confronting Sexually Transmitted Diseases. Washington, D.C.: National Academy Press, 1997. This collection of well-written essays is the recommendation of a sixteen-member expert committee for the prevention and control of STDs in the United States.
Larsen, Laura. Sexually Transmitted Diseases Sourcebook. Detroit, Mich.: Omnigraphics, 2009. A general resource on the symptoms and treatment of STDs such as chlamydia, gonorrhea, HIV, hepatitis, herpes, HPV, syphilis, and PID. Includes facts about prevalence, risk factors, diagnosis, treatment, and prevention. Also includes a glossary and a list of resources.
Little, Marjorie. Sexually Transmitted Diseases. Rev. ed. Philadelphia: Chelsea...
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Sexually Transmitted Diseases (Encyclopedia of Science)
Long known as venereal disease, after Venus, the Roman goddess of love, sexually transmitted diseases (STDs) are among the most common infectious diseases in the world. (An infectious disease is one caused by a parasite that attacks a host and begins to multiply, interfering with the normal life functions of the host.) There are more than 20 known STDs, ranging from life-threatening to painful and unsightly.
While acquired immunodeficiency syndrome (AIDS) is the most widely publicized STD, others are more common. Chlamydia, gonorrhea, and genital warts are nearing epidemic rates in the United States. Other common STDs include genital herpes, trichomoniasis, and chancroid (pronounced KAN-kroyd). STDs are most prevalent among teenagers and young adults under the age of 25 and affect individuals of all backgrounds and socioeconomic levels. Some STDs are caused by bacteria and usually can be treated and cured. Others are caused by viruses and can typically be treated but not cured. Untreated STDs pose an enormous public health problem.
STDs caused by bacteria include syphilis, gonorrhea, chlamydia, and chancroid. Syphilis is usually spread through sexual contact and begins with painless lesions (sores) called chancres (pronounced KAN-kerz) that may appear inside or outside the body. The disease occurs in four stages and eventually...
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Sexually Transmitted Diseases (STDS) (World of Microbiology and Immunology)
Sexually transmitted diseases (STDs) vary in their susceptibility to treatment, their signs and symptoms, and the consequences if they are left untreated. Some are caused by bacteria. These usually can be treated and cured. Others are caused by viruses and can typically be treated but not cured. As of June 2002, recent advancements in diagnosis now allow the identification of more than 15 million new cases of STD in the United States each year.
Long known as venereal disease, after Venus, the Roman goddess of love, sexually transmitted diseases are increasingly common. The more than 20 known sexually transmitted diseases range from the life-threatening to painful and unsightly. The life-threatening sexually transmitted diseases include syphilis, which has been known for centuries, some forms of hepatitis, and Acquired Immune Deficiency Syndrome (AIDS), which was first identified in 1981.
Most sexually transmitted diseases can be treated successfully, although untreated sexually transmitted diseases remain a huge public health problem. Untreated sexually transmitted diseases can cause everything from blindness to infertility. While AIDS is the most widely publicized sexually transmitted disease, others are more common. More than 13 million Americans of all backgrounds and economic levels develop sexually transmitted diseases every year. Prevention efforts focus on teaching the physical signs of sexually transmitted diseases, instructing individuals on how to avoid exposure, and emphasizing the need for regular check-ups.
The history of sexually transmitted disease is controversial. Some historians argue that syphilis emerged as a new disease in the fifteenth century. Others cite Biblical and other ancient texts as proof that syphilis and perhaps gonorrhea were ancient as well as contemporary burdens. The dispute can best be understood with some knowledge of the elusive nature of gonorrhea and syphilis, called "the great imitator" by the eminent physician William Osler (1849919).
No laboratory tests existed to diagnose gonorrhea and syphilis until the late nineteenth and early twentieth centuries. This means that early clinicians based their diagnosis exclusively on symptoms, all of which could be present in other illnesses. Symptoms of syphilis during the first two of its three stages include chancre sores, skin rash, fever, fatigue, headache, sore throat, and swollen glands. Likewise, many other diseases have the potential to cause the dire consequences of late-stage syphilis. These range from blindness to mental illness to heart disease to death. Diagnosis of syphilis before laboratory tests were developed was complicated by the fact that most symptoms disappear during the third stage of the disease.
Symptoms of gonorrhea may also be elusive, particularly in women. Men have the most obvious symptoms, with inflammation and discharge from the penis from two to ten days after infection. Symptoms in women include a painful sensation while urinating or abdominal pain. However, women may be infected for months without showing any symptoms. Untreated gonorrhea can cause infertility in women and blindness in infants born to women with the disease.
The nonspecific nature of many symptoms linked to syphilis and gonorrhea means that historical references to sexually transmitted disease are open to different interpretations. There is also evidence that sexually transmitted disease was present in ancient China.
During the Renaissance, syphilis became a common and deadly disease in Europe. It is unclear whether new, more dangerous strains of syphilis were introduced or whether the syphilis which emerged at that time was, indeed, a new illness. Historians have proposed many arguments to explain the dramatic increase in syphilis during the era. One argument suggests that Columbus and other explorers of the New World carried syphilis back to Europe. In 1539, the Spanish physician Rodrigo Ruiz Diaz de Isla treated members of the crew of Columbus for a peculiar disease marked by eruptions on the skin. Other contemporary accounts tell of epidemics of syphilis across Europe in 1495.
The abundance of syphilis during the Renaissance made the disease a central element of the dynamic culture of the period. The poet John Donne (1572-1631) was one of many thinkers of that era who saw sexually transmitted disease as a consequence of man's weakness. Shakespeare (1564-1616) also wrote about syphilis, using it as a curse in some plays and referring to the "tub of infamy," a nickname for a common medical treatment for syphilis. The treatment involved placing syphilitic individuals in a tub where they received mercury rubs. Mercury, which is now known to be a toxic chemical, did not cure syphilis, but is thought to have helped relieve some symptoms. Other treatments for syphilis included the induction of fever and the use of purgatives to flush the system.
The sculptor Benvenuto Cellini (1500571) is one of many individuals who wrote about their own syphilis during the era: "The French disease, for it was that, remained in me more than four months dormant before it showed itself." Cellini's reference to syphilis as the "French disease" was typical of Italians at the time and reflects a worldwide eagerness to place the origin of syphilis far away from one's own home. The French, for their part, called it the "Neapolitan disease," and the Japanese called it the "Portuguese disease." The name syphilis was bestowed on the disease by the Italian Girolamo Fracastoro (1478553), a poet, physician, and scientist. Fracastoro created an allegorical story about syphilis in 1530 entitled "Syphilis, or the French Disease." The story proposed that syphilis developed on Earth after a shepherd named Syphilis foolishly cursed at the Sun. The angry Sun retaliated with a disease that took its name from the foolish shepherd, who was the first individual to get sick.
For years, medical experts used syphilis as a catch-all diagnosis for sexually transmitted disease. Physicians assumed that syphilis and gonorrhea were the same thing until 1837, when Philippe Ricord (1800889) reported that syphilis and gonorrhea were separate illnesses. The late nineteenth and early twentieth centuries saw major breakthroughs in the understanding of syphilis and gonorrhea. In 1879, Albert Neisser (1855916) discovered that gonorrhea was caused by a bacillus, which has since been named Neisseria gonorrhoeae. Fritz Richard Schaudinn (1871906) and Paul Erich Hoffmann (1868959) identified a special type of spirochete bacteria, now known as Treponema pallidum, as the cause of syphilis in 1905.
Further advances occurred quickly. August von Wassermann (1866925) developed a blood test for syphilis in 1906, making testing for syphilis a simple procedure for the first time. Just four years later in 1910, the first effective therapy for syphilis was introduced in the form of Salvarsan, an organic arsenical compound. The compound was one of many effective compounds introduced by the German physician Paul Ehrlich (1854915), whose argument that specific drugs could be effective against microorganisms has proven correct. The drug is effective against syphilis, but it is toxic and even fatal to some patients.
The development of Salvarsan offered hope for individuals with syphilis, but there was little public understanding about how syphilis was transmitted in the early twentieth century. In the United States, this stemmed in part from government enforcement of laws prohibiting public discussion of certain types of sexual information. One popular account of syphilis from 1915 erroneously warned that one could develop syphilis after contact with whistles, pens, pencils, toilets, and toothbrushes.
In a tragic chapter in American history, some members of the U.S. Public Health Service exploited the ignorance of the disease among the general public as late as the mid-twentieth century in order to study the ravages of untreated syphilis. The Tuskegee Syphilis Study was launched in 1932 by the U.S. Public Health Service. The almost 400 black men who participated in the study were promised free medical care and burial money. Although effective treatments had been available for decades, researchers withheld treatment, even when penicillin became available in 1943, and carefully observed the unchecked progress of symptoms. Many of the participants fathered children with congenital syphilis, and many died. The study was finally exposed in the media in the early 1970s. When the activities of the study were revealed, a series of new regulations governing human experimentation were passed by the government.
A more public discussion of sexually transmitted disease was conducted by the military during World Wars I and II. During both wars, the military conducted aggressive public information campaigns to limit sexually transmitted disease among the armed forces. One poster from World War II showed a grinning skull on a woman dressed in an evening gown striding along with German Chancellor Führer Adolf Hitler and Japanese Emperor Hirohito. The poster's caption reads "V.D. Worst of the Three," suggesting that venereal disease could destroy American troops faster than either of America's declared enemies.
Concern about the human cost of sexually transmitted disease helped make the production of the new drug penicillin a wartime priority. Arthur Fleming (1881955), who is credited with the discovery of penicillin, first observed in 1928 that the penicillium mold was capable of killing bacteria in the laboratory; however, the mold was unstable and difficult to produce. Penicillin was not ready for general use or general clinical testing until after Howard Florey (1898968) and Ernst Boris Chain (1906979) developed ways to purify and produce a consistent substance.
The introduction of penicillin for widespread use in 1943 completed the transformation of syphilis from a lifehreatening disease to one that could be treated relatively easily and quickly. United States rates of cure were 907% for syphilis by 1944, one year after penicillin was first distributed in the country. Death rates dropped dramatically. In 1940, 10.7 out of every 100,000 people died of syphilis. By 1970, it was 0.2 per 100,000.
Such progress infused the medical community with optimism. A 1951 article in the American Journal of Syphilis asked, "Are Venereal Diseases Disappearing?" By 1958, the number of cases of syphilis had dropped to 113,884 from 575,593 in 1943, the year penicillin was introduced.
Venereal disease was not eliminated, and sexually transmitted diseases continue to ravage Americans and others in the 1990s. Though penicillin has lived up to its early promise as an effective treatment for syphilis, the number of cases of syphilis has increased since 1956. In addition, millions of Americans suffer from other sexually transmitted diseases, many of which were not known a century or more ago, such as Acquired Immune Deficiency Syndrome (AIDS) caused by the HIV virus. By the 1990s, sexually transmitted diseases were among the most common infectious diseases in the United States.
Some sexually transmitted diseases are seen as growing at epidemic rates. For example, syphilis, gonorrhea, and chancroid, which are uncommon in Europe, Japan and Australia, have increased at epidemic rates among certain urban minority populations. A 1990 study found the rate of syphilis was more than four times higher among blacks than among whites. The Public Health Service reports that as many as 30 million Americans have been affected by genital herpes. Experts have also noted that sexually transmitted disease appears to increase in areas where AIDS is common.
Shifting sexual and marital habits are two factors behind the growth in sexually transmitted disease. Americans are more likely to have sex at an earlier age than they did in years past. They also marry later in life than Americans did two to three decades ago, and their marriages are more likely to end in divorce. These factors make Americans more likely to have many sexual partners over the course of their lives, placing them at greater risk of sexually transmitted disease.
Public health officials report that fear and embarrassment continue to limit the number of people willing to report signs of sexually transmitted disease.
All sexually transmitted diseases have certain elements in common. They are most prevalent among teenagers and young adults, with nearly 66% occurring in people under 25. In addition, most can be transmitted in ways other than through sexual relations. For example, AIDS and Hepatitis B can be transmitted through contact with tainted blood, but they are primarily transmitted sexually. In general, sexual contact should be avoided if there are visible sores, warts, or other signs of disease in the genital area. The risk of developing most sexually transmitted diseases is reduced by using condoms and limiting sexual contactut can only be reduced to zero by having monogamous (one partner) sexual relations between partners who are free of disease or vectors of disease (e.g., the HIV virus).
Bacterial sexually transmitted diseases include syphilis, gonorrhea, chlamydia, and chancroid. Syphilis is less common than many other sexually transmitted diseases in the Unites States, with 134,000 cases in 1990. The disease is thought to be more difficult to transmit than many other sexually transmitted diseases. Sexual partners of an individual with syphilis have about a 10% chance of developing syphilis after one sexual contact, but the disease has come under increasing scrutiny as researchers have realized how easily the HIV virus which causes AIDS can be spread through open syphilitic chancre sores.
Gonorrhea is far more common than syphilis, with approximately 750,000 cases of gonorrhea reported annually in the United States. The gonococcus bacterium is considered highly contagious. Public health officials suggest that all individuals with more than one sexual partner should be tested regularly for gonorrhea. Penicillin is no longer the treatment of choice for gonorrhea, because of the numerous strains of gonorrhea that are resistant to penicillin. Newer strains of antibiotics have proven to be more effective. Gonorrhea infection overall has diminished in the United States, but the incidence of gonorrhea among certain populations (e.g., African-Americans) has increased.
Chlamydia infection is considered the most common sexually transmitted disease in the United States. About four million new cases of chlamydia infection are reported every year. The infection is caused by the bacterium Chlamydia trachomatis. Symptoms of chlamydia are similar to symptoms of gonorrhea, and the disease often occurs at the same time as gonorrhea. Men and women may have pain during urination or notice an unusual genital discharge one to three weeks after exposure. However, many individuals, particularly women, have no symptoms until complications develop.
Complications resulting from untreated chlamydia occur when the bacteria has a chance to travel in the body. Chlamydia can result in pelvic inflammatory disease in women, a condition which occurs when the infection travels up the uterus and fallopian tubes. This condition can lead to infertility. In men, the infection can lead to epididymitis, inflammation of the epididymis, a structure on the testes where spermatozoa are stored. This too can lead to infertility. Untreated chlamydia infection can cause eye infection or pneumonia in babies of mothers with the infection. Antibiotics are successful against chlamydia.
The progression of chancroid in the United States is a modern-day indicator of the migration of sexually transmitted disease. Chancroid, a bacterial infection caused by Haemophilus ducreyi, was common in Africa and rare in the United States until the 1980s. Beginning in the mid-1980s, there were outbreaks of chancroid in a number of large cities and migrant-labor communities in the United States. The number of chancroid cases increased dramatically during the last two decades of the twentieth century.
In men, who are most likely to develop chancroid, the disease is characterized by painful open sores and swollen lymph nodes in the groin. The sores are generally softer than the harder chancre seen in syphilis. Women may also develop painful sores. They may feel pain urinating and may have bleeding or discharge in the rectal and vaginal areas. Chancroid can be treated effectively with antibiotics.
As of June 2002, there are no cures for the sexually transmitted diseases caused by viruses: AIDS, genital herpes, viral hepatitis, and genital warts. Treatment to reduce adverse symptoms is available for most of these diseases, but the virus cannot be eliminated from the body.
AIDS is the most life-threatening sexually transmitted disease, a disease which is usually fatal and for which there is no cure. The disease is caused by the human immunodeficiency virus (HIV), a virus which disables the immune system, making the body susceptible to injury or death from infection and certain cancers. HIV is a retrovirus which translates the RNA contained in the virus into DNA, the genetic information code contained in the human body. This DNA becomes a part of the human host cell. The fact that viruses become part of the human body makes them difficult to treat or eliminate without harming the patient.
HIV can remain dormant for years within the human body. More than 800,000 cases of AIDS have been reported in the United States Centers for Disease Control since the disease was first identified in 1981, and at least one million other Americans are believed to be infected with the HIV virus. Initial symptoms of AIDS include fever, headache, or enlarged lymph nodes. Later symptoms include energy loss, frequent fever, weight loss, or frequent yeast infections. HIV is transmitted most commonly through sexual contact or through use of contaminated needles or blood products. The disease is not spread through casual contact, such as the sharing of towels, bedding, swimming pools, or toilet seats.
Genital herpes is a widespread, recurrent, and incurable viral infection. Almost a million new cases are reported in the United States annually. The prevalence of herpes infection reflects the highly contagious nature of the virus. About 75% of the sexual partners of individuals with the infection develop genital herpes.
The herpes virus is common. Most individuals who are exposed to one of the two types of herpes simplex virus never develop any symptoms. In these cases, the herpes virus remains in certain nerve cells of the body, but does not cause any problems. Herpes simplex virus type 1 most frequently causes cold sores on the lips or mouth, but can also cause genital infections. Herpes simplex virus type 2 most commonly causes genital sores, though mouth sores can also occur due to this type of virus.
In genital herpes, the virus enters the skin or mucous membrane, travels to a group of nerves at the end of the spinal cord, and initiates a host of painful symptoms within about one week of exposure. These symptoms may include vaginal discharge, pain in the legs, and an itching or burning feeling. A few days later, sores appear at the infected area. Beginning as small red bumps, they can become open sores which eventually become crusted. These sores are typically painful and last an average of two weeks.
Following the initial outbreak, the virus waits in the nerve cells in an inactive state. A recurrence is created when the virus moves through the nervous system to the skin. There may be new sores or simply a shedding of virus which can infect a sexual partner. The number of times herpes recurs varies from individual to individual, ranging from several times a year to only once or twice in a lifetime. Occurrences of genital herpes may be shortened through use of an antiviral drug which limits the herpes virus's ability to reproduce itself.
Genital herpes is most dangerous to newborns born to pregnant women experiencing their first episode of the disease. Direct newborn contact with the virus increases the risk of neurological damage or death. To avoid exposure, physicians usually deliver babies using cesarean section if herpes lesions are present.
Hepatitis, an inflammation of the liver, is a complicated illness with many types. Millions of Americans develop hepatitis annually. The hepatitis A virus, one of four types of viral hepatitis, is most often spread by contamination of food or water. The hepatitis B virus is most often spread through sexual contact, through the sharing of intravenous drug needles, and from mother to child. Hospital workers who are exposed to blood and blood products are also at risk. Hepatitis C and Hepatitis D (less commonly) may also be spread through sexual contact.
A yellowing of the skin, or jaundice, is the best known symptom of hepatitis. Other symptoms include dark and foamy urine and abdominal pain. There is no cure for hepatitis, although prolonged rest usually enables individuals with the disease to recover completely.
Many people who develop hepatitis B become carriers of the virus for life. This means they can infect others and face a high risk of developing liver disease. There are as many as 350 million carriers worldwide, and about 1.5 million in the United States. A vaccination is available against hepatitis B.
The link between human papillomavirus, genital warts, and certain types of cancer has drawn attention to the potential risk of genital warts. There are more than 60 types of human papillomavirus. Many of these types can cause genital warts. In the United States, about 1 million new cases of genital warts are diagnosed every year.
Genital warts are very contagious, and about two-thirds of the individuals who have sexual contact with someone with genital warts develop the disease. There is also an association between human papillomavirus and cancer of the cervix, anus, penis, and vulva. This means that people who develop genital warts appear to be at a higher risk for these cancers and should have their health carefully watched. Contact with genital warts can also damage infants born to mothers with the problem.
Genital warts usually appear within three months of sexual contact. The warts can be removed in various ways, but the virus remains in the body. Once the warts are removed the chances of transmitting the disease are reduced.
Many questions persist concerning the control of sexually transmitted diseases. Experts have struggled for years with efforts to inform people about transmission and treatment of sexually transmitted disease. Frustration over the continuing increase in sexually transmitted disease is one factor which has fueled interest in potential vaccines against certain sexually transmitted diseases.
A worldwide research effort to develop a vaccine against AIDS has resulted in a series of vaccinations now in clinical trials. Efforts have focused in two areas, finding a vaccine to protect individuals against the HIV virus and finding a vaccine to prevent the progression of HIV to AIDS in individuals who already have been exposed to the virus. One of many challenges facing researchers has been the ability of the HIV virus to change, making efforts to develop a single vaccine against the virus futile.
Researchers also are searching for vaccines against syphilis and gonorrhea. Experiments conducted on prisoners more than 40 years ago proved that some individuals could develop immunity to syphilis after inoculation with live Treponema pallidum, but researchers have still not been able to develop a vaccine against syphilis which is safe and effective. In part this stems from the unusual nature of the syphilis bacteria, which remain potentially infectious even when its cells are killed. An effective gonorrhea vaccine has also eluded researchers.
Immunizations are available against Hepatitis A and Hepatitis B (Hepatitis D is prevented by the Hepatitis B vaccine). The virus that causes Hepatitis C, however, is able to change its form (mutate) quite rapidly, thereby hampering efforts to develop a vaccine against it.
Without vaccinations for most of the sexually transmitted diseases, health officials depend on public information campaigns to limit the growth of the diseases. Some critics have claimed that the increasing incidence of sexually transmitted diseases suggest that current techniques are failing. In other countries, however, the incidence of sexually transmitted disease has fallen during the same period it has risen in the United States. For example, in Sweden the gonorrhea rate fell by more than 95% from 1970 to 1989 after vigorous government efforts to control sexually transmitted disease in Sweden.
Yet the role of government funding for community health clinics, birth control, and public information campaigns on sexually transmitted disease has long been controversial. Public officials continue to debate the wisdom of funding public distribution of condoms and other services that could affect the transmission of sexually transmitted disease. Although science has made great strides in understanding the causes and cures of many sexually transmitted diseases, society has yet to reach agreement on how best to attack them.
See also Bacteria and bacterial infection; Immunization; Immunogenetics; Public health, current issues; Virus replication; Viruses and responses to viral infection