Is Dried Blood Dangerous?

The article outlines the risks of contracting an illness from coming into contact with dried blood, how to properly clean contaminated surfaces, and what to do if you accidentally come into contact.

Exposure to any bodily fluid is dangerous and should be handled with caution. According to the CDC, blood is one of the most hazardous substances that you can come into contact with due to the risk of disease transmission. Many viruses and bacteria can survive for days on various surfaces, making dried blood a potential carrier of disease for up to 3-4 days after it has dried.

What Are the Risks of Dried Blood?

Bloodborne diseases are caused by pathogens that exist in blood and other body fluids. Pathogens are microorganisms that are carried in blood and can cause disease in people. Blood can contain a number of transmittable diseases including HIV, Hepatitis B, Hepatitis C, and methicillin-resistant Staphylococcus aureus (MRSA). 

Many bloodborne viruses can live for days outside of the body and still cause infection. The chances of getting sick depend on the type of pathogen, the type of contact, and the amount of virus in the source’s blood at the time of contact. 

HIV has been shown to survive in dried blood from a small cut or nosebleed for several days. One study performed in 2006, found that the virus survived for up to seven days on a syringe. However, the amount of surviving virus is reduced by 90-99 percent within a few hours of exposure to air and has a low risk of infection from coming into surface contact. In most cases, HIV will not be present in a large enough quantity in a small amount of blood to spread.

Hepatitis B and C have greater blood-to-blood transmission rate compared to HIV and are considered to the greatest risk from coming into contact with. The Hepatitis B virus can survive up to a week at room temperature and Hepatitis C can survive over 4 days at similar tempatures in dried blood.

MRSA has been shown to survive in a specimen of dried blood for up to two weeks. However, it is still being determined if the amount present in a small amount of blood is large enough to pass by contact on a surface. It is thought that the chances of catching MRSA would be poor.

How Could I get Sick from Dried Blood?

Bloodborne illnesses can be transmitted when coming into contact with mucous membranes (i.e. nose, mouth), damaged tissues (i.e cuts and scrapes), or cuts or punctures from contaminated items like needles or broken glass. Surfaces that have dried blood on them can potentially get you sick through cross-contamination. Cross-contamination is the spread of germs from one surface to another by contact. 

The greatest risk involves accidental skin punctures or direct contact with wounds or broken skin. For example, if you used a razor with dried blood on it belonging to a person with a bloodborne illness, you could potentially be at risk for contracting that illness.

How to Safely Clean Dried Blood from Surfaces

Although the changes of getting ill from contact with dried blood can be much lower than fresh blood, cleaning or handling surfaces that have been contaminated should be treated with the greatest precaution. No assumptions about the safety of contaminated surfaces should be taken. In many cases, what may appear to be “dried” blood can only be a couple of hours old and extremely dangerous.

Proper cleaning and handling steps to clean smaller stains include:

  1. The use of PPE’s such as gown, gloves and eyewear.
  2. Cleaning the affected area well with soap and water. This physically removes the contamination, but does not necessarily kill all microorganisms. Heat can help to kill viruses, so use the hottest water that can be safely handled.
  3. Use a disinfectant product with at least a 99% kill claim. A bleach solution of 1 part bleach to 9 parts water is a good disinfectant for killing a wide spectrum of pathogens. Pour onto contaminated area and let sit for 20 minutes.
  4. All non-disposable cleaning materials should be disinfected by saturating in a bleach solution and allowing to air dry. Disposable items should be disposed of by double bagging with a tough trash bag. 
  5. Hands should be thoroughly washed with soap and warm water after removing gloves.  

For larger areas, it may be best to contact a professional cleaning service that has experience with bioremediation cleaning.

For soft surfaces such as clothing, carpets, or furniture, heat and steam are the best way to kill viruses as long as the material can handle this type of cleaning. In some cases, it may be best to contact a professional cleaning service to avoid damage.

What Should I Do If I’ve Come into Contact with Dried Blood?

If you suspect that you have come into contact with dried blood or any other bodily fluid, wash the area immediately with soap and water. Reach out to your family doctor or health care professional to determine your risk factors and next steps. 

In cases of accidental skin punctures or cuts, allow the wound site to bleed naturally, never squeeze blood from it. Wash the area gently with soap and water. Don’t scrub the area and avoid any splashing or movements that would bring it closer to your face. Always immediately seek medical attention so your risk can be assessed and proper tests can be completed.

After coming into contact with dried blood, you could potentially pass on any contracted illness onto others so all precautions should be taken until you can undergo full testing. Sample precautions involve not sharing razors or toothbrushes, not donating blood, and taking care to not contaminate surfaces with bodily fluids. Your health care professional will guide you on the proper steps to take to protect yourself and others.

Immediately contact your health provider if you have any symptoms such as fever, jaundice, rashes, fatigue, reduced appetite, fatigue, nausea or vomiting, muscle aches, or in more cases swollen lymph nodes.

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