Skip directly to the search box, site navigation, or content.
Division of Foodborne, Bacterial and Mycotic Diseases (DFBMD)
Candidiasis
Frequently Asked Questions
I. Oropharyngeal Candidiasis, Esophageal Candidiasis (OPC)
- What is OPC?
- How common is OPC and who can get it?
- How do I get OPC?
- What are the symptoms of OPC?
- How is OPC diagnosed?
- How is OPC treated?
- What will happen if a person does not seek treatment for a OPC?
- Can OPC become resistant to treatment?
II. Genital/Volvovaginal Candidiasis (VVC)
- What is genital candidiasis/VVC?
- What are the symptoms of genital candidiasis/VVC?
- How is genital candidiasis/VVC transmitted?
- What are the symptoms of OPC?
- How is genital candidiasis/VVC diagnosed?
- How is genital candidiasis/VVC treated?
- What is the difference between the 3-day treatments and the 7 day treatments for genital candidiasis/VVC?
- Are over-the-counter (OTC) treatments for genital candidiasis/VVC safe to use?
- Can Candida infections become resistant to treatment?
- What will happen if a person does not seek treatment for genital candidiasis/VVC?
- How can someone tell the difference between genital candidiasis/VVC and a urinary tract infection?
III. Invasive Candidiasis
- What is invasive candidiasis?
- How common is invasive candidiasis and who can get it?
- What are the symptoms of invasive candidiasis?
- How is invasive candidiasis transmitted?
- How is invasive candidiasis diagnosed?
- How is invasive candidiasis treated?
I. Oropharyngeal Candidiasis, Esophageal Candidiasis (OPC)
Candidiasis of the mouth and throat, also known as a "thrush" or oropharyngeal candidiasis (OPC), is a fungal infection that occurs when there is overgrowth of fungus called Candida. Candida is normally found on skin or mucous membranes. However, if the environment inside the mouth or throat becomes imbalanced, Candida can multiply. When this happens, symptoms of thrush appear. Candida overgrowth can also develop in the esophagus, and is called Candida esophagitis, or esophageal candidiasis.
How common is OPC and who can get it?
OPC can affect normal newborns, persons with dentures, and people who use inhaled corticosteroids. It occurs more frequently and more severely in people with weakened immune systems, particularly in persons with AIDS and people undergoing treatment for cancer. Candida esophagitis usually occurs in people with weakened immune systems. It is very unusual in otherwise healthy people.
Most cases of OPC are caused by the person’s own Candida organisms which normally live in the mouth or digestive tract. A person has symptoms when overgrowth of Candida organisms occurs.
People with OPC infection usually have painless, white patches in the mouth. Others may have redness and soreness of the inside of the mouth. Cracking at the corners of the mouth, known as angular cheilitis, may occur. Symptoms of Candida esophagitis may include pain and difficulty swallowing. Other conditions can cause similar symptoms, so it is important to see your doctor.
OPC is often diagnosed based on the clinical appearance of the mouth and by taking a scraping of the white patches and looking at it under a microscope. A culture may also be performed. Because Candida organisms are normal inhabitants of the human mouth, a positive culture by itself does not make the diagnosis.
Prescription treatments include clotrimazole troches or lozenges and nystatin suspension (nystatin “swish and swallow”). Another commonly prescribed treatment is oral fluconazole. For infection which does not respond to these treatments, there are a number of other antifungal drugs that are available.
What will happen if a person does not seek treatment for a OPC?
Symptoms, which may be uncomfortable, may persist. In rare cases, invasive candidiasis may occur.
Can OPC become resistant to treatment?
Yes, OPC and Candida esophagitis can become resistant to antifungal treatment over time. Therefore, it is important to see your doctor for evaluation if you think you have OPC or Candida esophagitis.
II. Genital/Volvovaginal Candidiasis (VVC)
What is genital candidiasis/VVC?
Candidiasis, also known as a "yeast infection" or VVC, is a common fungal infection that occurs when there is overgrowth of the fungus called Candida. Candida is always present in the body in small amounts. However, when an imbalance occurs, such as when the normal acidity of the vagina changes or when hormonal balance changes, Candida can multiply. When that happens, symptoms of candidiasis appear.
What are the symptoms of genital candidiasis/VVC?
Women with VVC usually experience genital itching or burning, with or without a "cottage cheese-like" vaginal discharge. Males with genital candidiasis may experience an itchy rash on the penis.
How is genital candidiasis/VVC transmitted?
Nearly 75% of all adult women have had at least one genital "yeast infection" in their lifetime. On rare occasions, men may also experience genital candidiasis. VVC occurs more frequently and more severely in people with weakened immune systems. There are some other conditions that may put a woman at risk for genital candidiasis:
- Pregnancy
- Diabetes mellitus
- Use of broad-spectrum antibiotics
- Use of corticosteroid medications
Most cases of Candida infection are caused by the person’s own Candida organisms. Candida yeasts usually live in the mouth, gastrointestinal tract, and vagina without causing symptoms. Symptoms develop only when Candida becomes overgrown in these sites. Rarely, Candida can be passed from person to person, such as through sexual intercourse.
How is genital candidiasis/VVC diagnosed?
The symptoms of genital candidiasis are similar to those of many other genital infections. Usually the diagnosis is made by taking a sample of the vaginal secretions and looking at it under a microscope to see if Candida organisms are present.
How is genital candidiasis/VVC treated?
Several antifungal drugs are available to treat genital candidiasis/VVC. Antifungal vaginal suppositories or creams are commonly used. The duration of the treatment course of suppositories and creams ranges from single dose therapy to 7 days of therapy. Uncomplicated VVC may also be treated with single-dose, oral fluconazole. Oral fluconazole should be avoided in pregnancy. These drugs usually work to cure the infection (80%-90% success rate), but some people will have recurrent or resistant infections. Short-course treatments should be avoided in recurrent or resistant infection.
What is the difference between the 3-day treatments and the 7 day treatments for genital candidiasis/VVC?
The only difference between these is the length of treatment. Three-day and 7-day treatments may both be effective.
Are over-the-counter (OTC) treatments for genital candidiasis/VVC safe to use?
Over-the-counter treatments for VVC are available. As a result, more women are diagnosing themselves with VVC and using one of a family of drugs called "azoles" for therapy. However, misdiagnosis is common, and studies have shown that as many as two-thirds of all OTC drugs sold to treat VVC were used by women without the disease. Using these drugs when they are not needed may lead to a resistant infection. Resistant infections are very difficult to treat with the currently available medications for VVC.
Can Candida infections become resistant to treatment?
Overuse of these antifungal medications can increase the chance that they will eventually not work (the fungus develops resistance to medications). Therefore, it is important to be sure of the diagnosis before treating with over-the-counter or other antifungal medications.
What will happen if a person does not seek treatment for genital candidiasis/VVC?
Symptoms, which may be very uncomfortable, may persist. There is a chance that the infection may be passed between sex partners.
How can someone tell the difference between genital candidiasis/VVC and a urinary tract infection?
Because VVC and urinary tract infections share similar symptoms, such as a burning sensation when urinating, it is important to see a doctor and obtain laboratory testing to determine the cause of the symptoms and to treat effectively.
III. Invasive Candidiasis (VVC)
Invasive candidiasis is a fungal infection that occurs when Candida species enter the blood, causing bloodstream infection and then spreading throughout the body.
How common is invasive candidiasis and who can get it?
One form of invasive candidiasis, candidemia (a bloodstream infection with Candida), is the fourth most common bloodstream infection among hospitalized patients in the United States. A survey conducted at CDC found that candidemia occurs in 8 of every 100,000 persons per year. Persons at high risk for candidemia include very-low-birth-weight babies, surgical patients, hospitalized patients or patients with a central venous catheter, and those whose immune systems are weakened.
What are the symptoms of invasive candidiasis?
The symptoms of invasive candidiasis are not specific. Fever and chills that do not improve after antibiotic therapy are the most common symptoms. If the infection spreads to deep organs such as kidneys, liver, bones, muscles, joints, spleen, or eyes, additional specific symptoms may develop, which vary depending on the site of infection. If the infection does not respond to treatment, the patient’s organs may fail and cause death.
How is invasive candidiasis transmitted?
Invasive candidiasis is extremely rare in persons without risk factors. In persons at risk, invasive candidiasis may result when a person’s own Candida organisms, normally found in the digestive tract, enter the bloodstream. On rare occasions, it can also occur when medical equipment or devices become contaminated with Candida. In either case, the infection may spread throughout the body.
How is invasive candidiasis diagnosed?
Invasive candidiasis is usually diagnosed by either culture of blood or tissue or by examining samples of infected tissue under the microscope.
How is invasive candidiasis treated?
There are a number of antifungal drugs that are now available to treat invasive candidiasis. Fluconazole is a drug that can be taken by mouth or given intravenously (IV) to treat invasive candidiasis. Another class of antifungal drugs, the echinocandins, are also commonly used to treat invasive candidiasis. There are three echinocandins, all IV only: caspofungin, micafungin, and anidulafungin. All threse are effective in treating invasive candidiasis. Other drugs that are sometimes used to treat invasive candidiasis include voriconazole (by mouth or IV) and amphotericin B formulations (IV only).
Content Source: National Center for Zoonotic, Vector-Borne, and Enteric Diseases (ZVED)
Program Contents
Contact Information
