Sexually transmitted diseases are a growing problem across the globe. Despite several medical advancements, STDs continue to infect more people yearly.

Most sexually transmitted diseases have a dangerous course. While not all these diseases are without an effective cure, several STDs cannot be cured or are very hard to eliminate. These sexually transmitted diseases are caused mainly by viruses that are much better at hiding from the body's immune system than other pathogens. The worst STDs worldwide include hepatitis B, herpes, HIV, genital warts, and syphilis.
While this list mentions some of the worst STDs ranked in order, it does not mean they do not have any treatment. Early diagnosis and prompt treatment work wonder even if you acquire any STDs listed below.
TOP 5 WORST STDs RANKED IN ORDER
As mentioned before, STDs caused by viruses are generally the worst of the lot. Viruses are much better than other pathogens at hiding from the body's immune system and utilizing its resources to replicate. Their extreme resilience and adept nature allow them to linger on inside the body for years, even lifetimes. Therefore, it should not be surprising that most of the sexually transmitted diseases mentioned in this list of worst STDs are caused by viruses.
Here are the top 5 worst STDs ranked in order.
HERPES
Herpes is a chronic viral STD, which means that once contracted, the herpes virus stays inside the human body forever. Herpes is caused by the herpes simplex virus, which has two subtypes. This virus is very adept at hiding from the body's immune system. This virus also uses the body’s resources to replicate and spread throughout the body even more.
The main symptoms of herpes include sores, rash, and blisters. These symptoms can arise on and around the genitals if the person has genital herpes or around the lips if the person has oral herpes. These blisters are painful and itchy, and they also present a cosmetic concern. Patients with genital blisters may also experience pain during micturition and defecation.
The reason why herpes is one of the most dangerous sexually transmitted diseases is that this virus cannot be eliminated from the body. Moreover, herpes can also be a chronic, progressive disease, which means that a person who has had herpes for years may experience frequent and painful blister outbreaks. Once the disease has progressed to its final stage, it can induce irreversible nerve and brain damage!
Another factor that makes this sexually transmitted disease one of the worst STDs is that there is no cure or vaccine for this infection. Anti-viral drugs help reduce the frequency and severity of symptomatic outbreaks, but they do not completely cure this disease. Symptomatic outbreaks can also appear randomly through environmental triggers, such as stress and anxiety.

HIV
HIV is the other chronic sexually transmitted disease, syphilis being the first one. HIV is well-known around the globe as it has infected thousands of people in both the developed and the developing world.
HIV infection is caused by the human immunodeficiency virus, which, as the name suggests, attacks the body's immune system. This pathogen seeks out the CD4+ T cells, which form an integral part of cell-mediated immunity and render them ineffective. The result is that the infected person becomes exceptionally vulnerable to every infection they may be exposed to in the environment. Most people who have HIV expire due to the superadded opportunistic infections and not from the direct effects of the virus itself.
This infection does not have any specific symptoms. A person's initial symptoms weeks after contracting the virus may mimic the symptoms of a common cold. An infected person may have a headache, a runny nose, cough, and fever. Advanced stages of the disease may even present with gum bleeds, petechial rashes, and organ failure. AIDS, called autoimmune deficiency syndrome, is also a feature of the late stage of this infection, where the infected person becomes highly vulnerable to opportunistic infections.
HIV is on the list of the 5 worst STDs ever because this infection, like herpes, never goes away. The HIV-causing virus lives inside the ganglions, where it hides from the immune cells.
While this infection does not have a cure, it does have an effective treatment regimen. Anti-retroviral drugs, also called ART, provide effective relief and lower a person's viral load – the number of viral particles in their blood. There are several prophylactic treatment regimens available for HIV as well.

HPV
HPV, or the human papillomavirus, causes another incurable sexually transmitted disease. However, this infection is not chronic as the two infections mentioned above. HPV infects a person's genitals and gives rise to genital warts – painful blisters or sores in or on the genitals. These warts can also be found in or around the rectum, and they cause intense itching and pain.
HPV is very common. About 90% of sexually active people contract this virus at least once. However, most of these infections resolve spontaneously in a couple of years.
This infection seems a little mild compared to the last two, but there is more to this virus than meets the eye. HPV can cause several forms of cancers, including cervical and oral cancers. HPV is a common cause of cervical cancer in women of reproductive age. A sexually transmitted disease that has the potential to cause cancers should be ranked high in the list of the 5 worst STDs ever.
HEPATITIS B
Hepatitis B is caused by the hepatitis B virus, one of the many hepatitis viruses. This infection causes massive liver inflammation, which can be both acute and chronic. Most of these infections, however, turn chronic as the acute phase of the disease does not present with any specific symptoms, or there are no symptoms at all.
This infection induces an inflammatory response in the liver, which can cause acute liver failure. However, the acute phase of the infection may not be as aggressive and resolve on its own after a couple of months. In some individuals, however, the infection turns chronic and causes chronic liver damage.
Chronic liver damage can cause years of wear and manifest as impaired liver function. Liver function tests may reveal depressed liver functions and inadequate excretion of toxic substances. There can also be a deficiency of clotting factors, most of which are manufactured in the liver. A person with chronic hepatitis B may present with gum bleeds, non-healing ulcers, and petechial hemorrhages.
Chronic liver damage may also lead to most of the normal liver tissue being replaced by fibrous tissue. This fibrosis is an attempt by the body to replace the damaged tissue in the liver. However, the newly deposited fibrous tissue cannot perform the same functions as normal liver tissue. Fibrosis can lead to permanent, irreversible cellular changes, which may lead to liver cancer.
While this infection is dangerous, several treatment options are available. There is also a vaccination available for hepatitis B, which grants substantial immunity against the virus.

SYPHILIS
The last sexually transmitted disease on this list is syphilis. Syphilis, unlike all other STDs listed here, is caused by a bacteria: Treponema pallidum. This bacteria can be transferred to other people through unprotected sexual intercourse. Syphilis can also be transmitted to other people through contact with the skin in areas not covered by a condom.
Since syphilis is a bacterial STD, it can be cured quite easily. Bacterial STDs, unlike viral STDs, are much easier to treat as the bacteria are not as adept at avoiding the immune system as viruses. However, syphilis is on this list of the 5 worst STDs because this infection can cause severe nerve and brain damage if not treated properly.