onchocerciases

The spread of a disease doesn't stop at a country's borders. With more people living in crowded cities and traveling to other countries, it's easier for germs to spread. Infectious diseases that start in one part of the world can quickly reach another part of the world. Some of the major diseases currently affecting countries around the globe include HIV, malaria, COVID-19, and tuberculosis.

Besides the spread of diseases, there are other global health challenges. Resistance to medicines such as antibiotics is on the rise. That makes it harder to treat certain diseases. Natural and man-made disasters create refugee populations with immediate and long-term health problems. Climate change and not enough access to food and safe water are also global problems which can affect people's health. Many countries and health organizations are working together and sharing information on these and other health issues.

Parasites are living things that use other living things - like your body - for food and a place to live. You can get them from contaminated food or water, a bug bite, or sexual contact. Some parasitic diseases are easily treated and some are not.

Parasites range in size from tiny, one-celled organisms called protozoa to worms that can be seen with the naked eye. Some parasitic diseases occur in the United States. Contaminated water supplies can lead to Giardia infections. Cats can transmit toxoplasmosis, which is dangerous for pregnant women. Others, like malaria, are common in other parts of the world.

If you are traveling, it's important to drink only water you know is safe. Prevention is especially important. There are no vaccines for parasitic diseases. Some medicines are available to treat parasitic infections.

Your skin is your body's largest organ. It has many different functions, including covering and protecting your body. It helps keep germs out. But sometimes the germs can cause a skin infection. It often happens when the germs enter your body through a break, cut, or wound on your skin. Other skin infections can happen in places where the skin rubs together, especially if the area is moist. Infections can also happen when you have a poor blood supply to an area of your body or if your immune system is weakened because of another disease or a medical treatment.

Some skin infections cover a small area on the top of your skin. Other infections can go deep into your skin or spread to a larger area.

Skin infections are caused by different kinds of germs. For example,:

• Bacteria cause cellulitis, impetigo, and staphylococcal (staph) infections
• Viruses cause shingles, warts, and herpes simplex
• Fungi cause athlete's foot and yeast infections
• Parasites cause body lice, head lice, and scabies

You are more likely to get a skin infection if you:

• Have poor circulation
• Have diabetes
• Are older
• Have an immune system disease, such as HIV
• Have a weakened immune system because of chemotherapy or other medicines that suppress your immune system
• Have to stay in one position for a long time, such as if you are sick and have to stay in bed for a long time or you are paralyzed
• Are malnourished
• Have excessive skinfolds, which can happen if you have obesity

The symptoms depend on the type of infection. Some symptoms that are common to many skin infections include rashes, swelling, redness, pain, pus, and itching.

To diagnose a skin infection, your health care provider will do a physical exam and ask about your symptoms. You may have lab tests, such as a skin culture. This is a test to identify what type of infection you have, using a sample from your skin. Your provider may take the sample by swabbing or scraping your skin or removing a small piece of skin (biopsy). Sometimes providers use other tests, such as blood tests.

The treatment depends on the type of infection and how serious it is. Some infections will go away on their own. When you do need treatment, it may include a cream or lotion to put on the skin. Other possible treatments include medicines and a procedure to drain pus.