Night blindness: Vitamin A deficiency

Myopia (nearsightedness) is a common condition that's usually diagnosed before age 20. It affects your distance vision — you can see objects that are near, but you have trouble viewing objects that are farther away.

Hepatitis B is an infection of the liver caused by the hepatitis B virus. The infection can be acute (short and severe) or chronic (long term). Hepatitis B can cause a chronic infection and puts people at high risk of death from cirrhosis and liver cancer.

Herpes is a common virus that causes sores on your genitals and/or mouth. Herpes can be annoying and painful, but it usually doesn’t lead to serious health problems.

Herpes is spread from skin-to-skin contact with infected areas, often during vaginal sex, oral sex, anal sex, and kissing. Herpes causes outbreaks of itchy, painful blisters or sores that come and go.

Herpes is caused by two different but similar viruses: herpes simplex virus type 1 (HSV-1) and herpes simplex virus type 2 (HSV-2). Both kinds can make sores pop up on and around your vulva, vagina, cervix, anus, penis, scrotum, butt, inner thighs, lips, mouth, throat, and rarely, your eyes.

Chlamydia is a bacterial infection. The bacteria are usually spread through sex or contact with infected genital fluids (semen or vaginal fluid). You can get chlamydia through: unprotected vaginal, anal or oral sex. sharing sex toys that are not washed or covered with a new condom each time they're used.

Symptoms of chlamydia

Many people with chlamydia have no symptoms or only mild symptoms. If symptoms occur, they may not appear until up to three weeks after having sex with someone who has chlamydia.

In women, common symptoms include:
1. a change in vaginal discharge
2. bleeding between menstrual periods or after sex
3. pain or discomfort in the lower abdomen
4. burning sensation when urinating

Common symptoms in men include:
1. burning when urinating
2. discharge from the penis
3. pain or discomfort in the testicles

Anal infection in women and men can cause:
1. pain
2. discharge
3. bleeding

Chlamydia can also infect the throat often without symptoms.

Infants born to mothers with chlamydia may experience eye infections or pneumonia. These can be treated with antibiotic medications for newborns.

The prostate gland is a male reproductive organ that produces fluids that feed and protect sperm cells.

The three most common forms of prostate disease are:
1. inflammation (prostatitis)
2. non-cancerous enlargement (BPH)
3. prostate cancer