Gonorrhoea is an STD caused by Neisseria gonorrhoeae. It mainly has a negative influence on the genital system.

Usually, the symptoms occur within 2 to 14 days after the infection, including burning pain during urination. For females, there could be much yellow pus vaginal discharge, unusual bleeding during the periods, or even pelvic inflammation. For males, there could be thick urethral secretions or prostatitis. Fever and joint swelling (Arthritis) could also appear.

Chlamydia is an STD caused by Chlamydia trachomatis. It mainly has a negative influence on the genital system.

Among the infection of Chlamydia, approximately half of the people have asymptomatic infection but still possess transmissibility. The symptoms normally appear within 1 to 3 weeks after the infection, including an unusual increase in the genital secretions, burning pain during urination, or abdominal pain. If the situation is critical, females might have a pelvic infection (influence on the ovary and the uterine tube).

Genital warts are caused by HPV (human papillomavirus). HPV could be divided into HR-HPV (High-risk HPV) such as types 16 and 18 or LR-HPV (Low-risk HPV) such as types 6 and 11. LR-HPV may cause genital warts.

Usually, the symptoms appear within 3 weeks to 3 months after the infection, the common lesion appears on the genital, sometimes might also be found around the anus, perineum, or even the intravaginal part and the cervix. There will be pink or white warts on the affected area, the wart could be just a single one or multiple ones or even aggregate as a big area on the body; both males and females could feel the affected area itchy and burning sensation.

Nowadays, there are multivalent vaccines such as the 2-valent vaccine which could prevent HR-HPV and the 4- and 9-valent vaccines which could prevent both HR-HPV and genital warts. The 4-valent vaccine could prevent 70% of oncogenic HPV, 90% of HPV that causes genital warts, 70% of cervical cancer, 50% of anal cancer, and it is able to prevent about 35% to 50% of anal cancer’s pre-malignancy; the 9-valent vaccine could reduce 15% incidence rate of cervical cancer and 10% incidence rate of anal cancer. The market in Taiwan currently offers 9-valent vaccines, and it is recommended for men and women aged from 9 to 45 to apply.

Amoebiasis is caused by Entamoeba histolytica, the human body could be infected with Amoebiasis via the faecal-oral contact of the oocyst at the anus.

Entamoeba histolytica is an intestinal parasite, most of the infected patients do not show obvious symptoms, normally, the latent period is around 2 to 4 weeks whilst the infection could last for many years. Entamoeba histolytica could invade the intestinal wall tissue which leads to intestinal symptoms, such as abdominal discomfort, intermittent diarrhea, or constipation; and also happen along with fever, chillness, bloody stool, or mucus in stool. And there are about 10% of invasive Amoebiasis infections that could invade the liver through blood flow and cause an amoebic liver abscess.

Pthirus pubis is a parasitic insect that lives on human hair, it is usually to be found in the perineal area. Besides the perineal area, it could also be living on hairs, eyelashes, beards, and armpit hair. The main transmission method is via sexual behaviour, but contact with any contaminated clothes or sheets could also cause an infection of Pthirus pubis.

The symptoms of Pthirus pubis include itching in the perineal area (especially at night), rashes, papule, blood scabs, or green bruises in the perineal area; powdered or grained rust colour faeces could also be found on the underwear, and rust or reddish-brown oval eggs could appear on the pubic hair root.

Hepatitis A is viral hepatitis, the latent period is about 15 to 50 days (with an average of 28 to 30 days). The main transmission method of it is via the faecal-oral route which means the infection could happen due to the contact with the contaminated water or food; if the hands have contact with the faeces of the infected person and are not thoroughly cleaned, and then contact with food or mouth may also cause indirect infection.

Usually, the severity of clinical symptoms of hepatitis A increases with age. Most of the infection in childhood has no clinical symptoms or just mild symptoms, no sequelae or recurrence after recovery, and the mortality rate is only about 1 in 1,000 (mostly happens to the elder patients).

The hepatitis A symptoms are fever, fatigue, poor appetite, and jaundice will appear in a few days.

Hepatitis A vaccine is the most effective prevention method, the hepatitis A vaccine has reliable safety and efficiency credit. It consists of 2 doses with an interval of 6 to 12 months. The protective effect of the vaccine is over 97%, and the immunity can be maintained for more than 20 years.

Hepatitis B is viral hepatitis, its main routes of infection are through body fluid, blood, close contact, blood transfusion, and injection. And it can be divided into the vertical and the horizontal transmission.

Vertical transmission｜A vertical transmission means that a mother who is a hepatitis B virus carrier passes the virus to the newborn before and after giving birth. In the past, about 40 to 50% of the carriers in Taiwan passed the infection through this route.

Horizontal transmission｜Blood or body fluids containing viruses enter the body through the skin or mucous and lead to an infection, so having an unexamined blood transfusion and its preparations, sharing needles or syringes, acupuncture, ear piercing, eyebrow tattooing, tattooing, sharing toothbrushes or razors, risky sexual behaviour, etc., could cause hepatitis B infection.

The symptoms of hepatitis B are usually insignificant, including anorexia, mild abdominal pain, nausea, and vomiting, and sometimes joint pain, rash, jaundice, and mild fever could appear. The severity could be divided into the asymptomatic infection that could only be confirmed with the serological test methods to fulminant hepatitis which is lethal.

An adult who has a blood draw test negative for hepatitis B surface antigen (HBs Ag) and hepatitis B surface antibody (Anti-HBs Ab) should inject the hepatitis B vaccine.

If one who has ever injected hepatitis B vaccine, the antibody levels will gradually decrease after 5 to 10 years. Hence the hepatitis B surface antibody might not be detectable but once there is a virus infection, the antibody could still increase to fight the virus. It may be considered that to have 1 dose of self-paid hepatitis B vaccine and do the blood draw test a month later, if the surface antibody is still negative, then the 2nd. and the 3rd.dose could be completed and injected with the recommended schedule.

Hepatitis C transmits through the blood or body fluid with hepatitis C virus entering the human body through skin or mucosa. The latent period of hepatitis C is 2 to 24 weeks, normally 6 to 9 weeks. It should be noted that after recovery from hepatitis C treatment, protective immunity will not be generated, so reinfection may be possible through the same route.

Fatigue, epigastric bloating, anorexia, or jaundice may be present with acute infection. The severity of the illness can range from insignificant symptoms to fulminant hepatitis, which can lead to a fatal condition, but most symptoms are mild or asymptomatic.

There is currently no vaccine to prevent hepatitis C.