How to Tell the Difference Between Herpes and Pimples (With Photos)
Herpes vs. Pimples
Both herpes and pimples can occur in various areas on the body, most commonly on the face (around the mouth) and in the genital region. Although this article will focus more on the mouth region, occurrences are similar anywhere on the body. Herpes and pimples may have a similar appearance and be equally uncomfortable or painful, but there are a few key differences that can help you easily tell them apart.
Differences Between Herpes Blisters and Pimples
Sensitive, itching sensation
Only hurts when touched
Usually forms in clusters
Pimples can form individually
Caused by a viral infection
Caused by bacterial infection and inflammation
Filled with a clear liquid and will break to form scabs
Filled with white pus
Lie on the surface of the skin
Can extend into deeper layers of the skin
Pictures of Herpes BlistersClick thumbnail to view full-size
Stages of Herpes Development
Once you get infected by the herpes virus, you may start to develop symptoms (enter stage 1), or the virus may enter a latent phase in which it lies dormant until something triggers an outbreak. At this time, it is unclear why this is and what the exact triggers are.
Stage 1: Prodrome or Viral Shedding (Days 1-2)
This is the beginning of the replicative phase of the herpes virus lifecycle. Within the first few days of an outbreak, the virus will make contact with the skin and begin replicating as it prepares to break out and infect other hosts. This initiates an inflammatory response that causes you to feel tightness, tingling, itchiness, burning sensation, and possibly some swelling. You may or may not be able to see physical symptoms (i.e. small reddish bumps) at this stage.
You are considered contagious during this period and should avoid physical contact with other people or shared objects (e.g. eating utensils, cups, straws, phones, etc.).
Stage 2: Blister Formation (Days 2-7)
Depending on the severity and the person, the infection can lead to the formation of blisters within a few days. Blisters are seen as clusters of fluid-filled sacs that are clear, yellowish, or white (pus). The fluid in a herpes sore is generally a mixture of plasma, interstitial fluid, cellular debris, and the virus itself. The blisters can be itchy and painful and usually last around two days before they burst on their own.
You are the most contagious during this stage since the concentration of the virus on the surface of the body is at its highest.
Stage 3: Bursting and Crusting (Days 5-10)
A few days after the blisters form, they will burst on their own, releasing the fluid along with the virus. This may also cause some bleeding and subsequent scabbing. The sore will then dry out and begin to heal. As new skin starts to form over the next few days, the affected area may be very itchy.
Stage 4: Complete Healing (Days 7-14)
Once the scab falls off—you should let it fall off naturally to minimize scarring—and the new skin covers the old blisters, the virus will move back into the dormancy phase of its infection. During this phase, the virus will continue to live in your body—in the nerve roots in your spinal cord—without causing any symptoms until it is once again triggered.
Causes of Oral and Genital Herpes
Herpes is very infectious and also very common. Two studies published in PLOS ONE estimated that in 2012, 67% of people worldwide who are under 50 are infected with HSV-1, and 11.3% of people ages 14-49 are infected by HSV-2. Some people may not be aware that they are infected because it is possible for the virus to stay dormant and not cause any symptoms until an outbreak is triggered. People with herpes sores often confuse them with common skin problems such as rashes, pimples, bug bites, razor burns, ingrown hairs, or yeast infections.
Herpes sores are caused by one of two subtypes of the herpes simplex virus (HSV):
- HSV-1: Usually causes oral herpes (herpes labialis), including cold sores and fever blisters
- HSV-2: Usually causes genital herpes (herpes genitalis) and sores in other areas of the body
It should be noted that either subtype of the herpes simplex virus can infect any part of the body, usually through oral sex. That is, HSV-1 can cause genital herpes, and HSV-2 can cause an oral infection.
For some people, the first outbreak after a herpes infection is the worst, although others may have little to no symptoms at all. The first episode is generally accompanied by flu-like symptoms:
- Swollen lymph nodes
- Joint pain
What Does Herpes Look Like?
- Itchy rash
- Sensitive, reddish, inflamed skin
- Clusters of small, blisters filled with clear fluid
The first occurrence of herpes is usually the most painful and lasts about two weeks. Subsequent episodes are less likely to occur, although some people may have recurrent episodes. It is estimated that about 40% of American adults get reoccurring cold sores. Those infected with HSV-2 are more likely to experience recurring herpes outbreaks. These subsequent outbreaks are generally milder than the first and last about a week. This is because the body has created antibodies against the virus and is therefore more prepared to fight off the infection. Those infected with HSV-2 are more likely to experience recurring herpes outbreaks than those infected with HSV-1.
Herpes tend to form in irregular clusters of blisters.
How Do You Catch Herpes?
Herpes is spread through direct contact with a person or the bodily fluids of a person that is infected with the virus—such as contact with blisters and ulcers—but most commonly occurs through kissing and sex (oral, vaginal, and anal). Herpes cannot be spread through contact with objects touched by an infected person, since the virus cannot survive long outside of the body. However, avoid contact with objects that may have the infected person’s bodily fluids on them, such as eating utensils, straws, cups, towels, and lip balm.
Once you are infected, you will always carry the virus—even when symptoms do not appear. The virus will stay dormant until common triggers, like stress, illness, and UVB rays from the sun, cause an outbreak to occur.
How Do You Know If You Have Herpes?
Often times, you can tell the difference between herpes sores and pimples just by looking at them. However, for a definitive answer, it is best to seek out a licensed healthcare provider, who can find out if you are infected with herpes using one or a combination of three possible diagnostic tests:
- Culture test: A fluid sample from a blister or ulcer—preferably a new one—is cultured to detect whether the herpes virus is present. This test is most sensitive within 48 hours of initial symptoms and is usually done during the first episode.
- Blood test: This tests for presence of antibodies for the two types of herpes viruses (HSV-1 and HSV-2). Therefore, it is usually done weeks after the first episode, since it takes time for the body to create antibodies to fight a virus. Because this test detects antibodies specific to the virus, it can tell you what type of herpes simplex virus you are infected with and can be useful in determining the likelihood of future episodes.
- Polymerase chain reaction (PCR) test: This test is used to detect the presence of genetic material from the herpes virus. It is the most sensitive test but also the most expensive test, so it is not generally ordered, except in extreme cases.
Can You Pop Herpes Blisters?
Like pimples, you may be tempted to pop a cold sore or a herpes blister, but by popping, you are only doing more harm. Popping a cold sore, a genital herpes blister, or a pimple increases the risk that you will worsen the existing infection, introduce a secondary infection, or irritate your skin further. Popping can also make it more likely to form a scar.
It is best to leave the pimples or blisters alone to heal on their own, but if they are too uncomfortable or painful, talk to your doctor.
Don't Risk It!
Although you can likely tell herpes sores and pimples apart just by looking at them, a medical diagnosis will let you know for sure.
Pictures of PimplesClick thumbnail to view full-size
What Do Pimples Look Like?
There are many types of acne, including blackheads (open comedones), whiteheads (closed comedones), papules, pustules, nodules, and cysts. The ones most often confused with cold sores are papules and pustules, which are bumps filled with white or yellow pus. Papules appear as small pink or red bumps, while pustules are similar with a white or yellow cap.
- Pink or red bumps
- Appear alone or in clusters
- Firm and sensitive to the touch
- Can be itchy or irritate the skin
- Can be painful if pressure is applied
How Long Do Pimples Usually Last?
Depending on the type of pimple you get, each pimple can last from a couple days to about two weeks. Pimples with a lot of pus may take longer to heal. They will likely heal faster when kept clean and undisturbed. Constantly touching—especially popping—a pimple can make it larger, more uncomfortable, and delay the healing process.
Pimples have a regular, round shape and can appear as a single pimple.
How Do Pimples Form?
Papules and pustules are caused by inflammation of clogged hair follicles. Buildup of oil (sebum) and dead skin can trap bacteria in the follicle, leading to an infection. To combat this infection, the immune system starts an inflammatory response that increases blood flow to the area—causing the redness you see—and recruits cells to trap and fight the bacteria. This process forms pus—the collection of dead cells and tissue, bacteria, white blood cells, blood serum, and other debris.
What Triggers Pimple Formation?
- Excess oil on the skin: This can come from excess sebum production or from contact with oily products like greasy foods or oily lotions and creams.
- Puberty: Increases in androgen production, which leads to increased sebum production.
- Genetics: If you have a family history of acne, you are more likely to develop it yourself.
- Diet: Contrary to popular belief, eating greasy foods like chips and burgers has not been found to affect acne. That being said, the relationship between diet and acne still needs further exploration, but some studies do suggest that certain foods can exacerbate acne, including high glycemic foods (i.e. foods that contain simple sugars like soda and candy), chocolate, and dairy.
Stages of Pimple Development
Stage 1: Clogged Pore (Day 1)
A pimple generally starts with a clogged hair follicle. This may be seen as a blackhead (may also be dark yellow), if it is an open comedo, or a whitehead, if it is a closed comedo. At this stage, the skin may or may not be raised, and there may be some redness around the head as inflammation begins.
Stage 2: Papule (Day 2)
The sebaceous glands around the hair follicle continue to produce sebum, but because the follicle is now plugged, the sebum builds up, pressing on the skin above and against the walls of the follicle. This can be seen as a raised bump that makes the skin feel tight and can be painful to the touch. A bacterial infection is also possible, which would increase inflammation and may lead to the formation of a cyst.
Stage 3: Pustule (Days 2-6)
If the sebum bursts the walls of the hair follicle, the papule may become a pustule. A pustule is filled with a mixture of sebum, cellular debris, white blood cells, and bacteria. The pustule might feel a bit looser than the papule, and it may be tempting to pop the pimple, but resist the urge to do so. Popping a pustule might make the infection worse and actually make the pimple last longer.
Stage 4: Nodule or Cyst (Days 3-7)
If there is a bacterial infection, the pimple may extend deeper into the skin and form a nodule or cyst. These cover a larger area of the skin and can be very painful.
Stage 5: Complete Healing (Days 3-10)
Depending on the severity and the individual, pimples can last anywhere from a few days to over a week. As long as the pimple was left alone, it will rarely result in a scar. The pus will simply drain into the body's filtration system to be discarded, and the pimple will disappear, possibly leaving a bit of discoloration. However, scars can easily form if cysts break the surface of the skin.
Is It Pimples, Herpes, or Razor Burns?
Razor burns also have the symptoms of red skin and itchiness and can also create small bumps that resemble pimples or herpes blisters. Small cuts when shaving the face or the genital region can irritate the skin increase the risk of an infection. This is made worse by the possibility of ingrown hairs. To combat the irritation or infection, the body may respond with inflammation and recruitment of white blood cells, resulting in the formation of small, pus-filled bumps. If you notice these bumps, and you recently shaved, that's most likely what caused them.
As mentioned, the small cuts increase the risk of an infection. Practice good hygiene and disinfect the area immediately after shaving help reduce skin irritation and prevent an infection from occurring.
If You Still Can't Tell
When in doubt, it’s generally best to see your physician. Don't be ashamed. Genital herpes is extremely common. If you have herpes, it is possible to keep it in check, and understanding your options can help you live with the virus.
Other Helpful Tips
- Time will tell. Herpes occurs in cycles. Take some time to notice what your body is showing you. Pay attention to the herpes blister life cycle and continue to look for any additional symptoms, such as fever or muscle tenderness. If "pimples" with a burning sensation occur in the same area after a period of time, it is probably herpes.
- Evaluate the location. Do the "pimples" occur near your genitals, rectum, or mouth? Those are all common areas for herpes. Herpes symptoms are usually the same no matter where the virus is found on the body, although the location may impact the seriousness of the symptoms.
This article is for informational purposes only and is not meant to be used to diagnose. When in doubt, it’s best to see your physician. Don't be ashamed. Genital herpes is extremely common.
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