Comparison of acute HIV symptoms to similar-looking conditions

Mononucleosis vs. early HIV

Here you will learn the difference between mononucleosis and early retroviral syndrome (early HIV) from a doctor’s viewpoint.

Mononucleosis, or mono, is a common condition that affects a lot of people (mostly young people). It is usually a self-limiting condition, unlike early retroviral syndrome, which needs to be differentiated from mono and treated with HIV-specific medication.

Signs and symptoms such as fever, headache, rash, and sore throat can occur with both conditions. Therefore, when differentiating between the two, it’s important to analyze the sign and symptoms within the right context. That means we must consider the following:

• What preceded the event (a new sexual partner or close contact with a person with mono, for instance)
• How the disease has been evolving over time
• Any additional signs and symptoms

Prevalence

The table below summarizes US statistics regarding newly diagnosed cases of mononucleosis and acute retroviral syndrome each year. Knowing these numbers is a first step toward understanding which, in general, is more likely. Obviously, we must look at other information to be more precise in our assumptions.

Signs and symptoms: differences and similarities

Incubation period

The incubation period is the time after exposure before symptoms appear.

• Mono’s incubation period is a bit longer: 4–6 weeks post exposure
• HIV: 2-4 weeks

Speed of disease onset

Mononucleosis signs and symptoms begins gradually, unlike HIV, which has a more acute (sudden) start.

Fatigue

Both conditions present with fatigue, but the severity and duration are different.

• Mononucleosis
  • One of the most important and significant symptoms of mononucleosis is fatigue. It is usually very significant and long-lasting. Most other symptoms resolve before the fatigue goes away.
• Early HIV
  • Fatigue is a common symptom of early HIV, but it’s a normal fatigue like people get with any viral infection.

Sore throat

Both conditions also present with sore throat, but mononucleosis has more significant signs and symptoms.

• Mononucleosis
  • Redness, swelling, white patches, and exudate can appear and last for 6 to 10 days. Swallowing is very painful.

Dr. P Marazzi / science photo library

• Early HIV
  • Tonsillar enlargement occurs without redness or white patches.

Lymph nodes enlargement

Both conditions can present with lymph nodes enlargement, but with minor yet important differences.

• Mononucleosis
  • With mono, the lymph nodes in the neck and armpits tend to be enlarged. Usually, the back of the neck and back of the ear lymph nodes are enlarged. They are mildly tender to the touch. They go back to normal over time.
• Early HIV
  • In addition to neck and armpit lymph nodes enlargement, early HIV can cause enlargement in other areas as well. The lymph nodes are usually not tender to the touch. The lymph nodes become enlarged during the second week and get better over time. They can remain enlarged even after the initial symptoms resolve.

Weight loss

Both conditions can cause suppressed appetite and weight loss. It is more common and pronounced with HIV (the average weight loss with HIV is 6 kg or 13 lbs).

Headache

Headache is a very nonspecific sign that occurs with both conditions, but with HIV it is more severe and located in the orbital area (that is, the eye area) and gets worse with eye movement.

Oral lesions

Both conditions can affect the oral cavity, but painful oral sores are a very distinctive feature of early HIV infection

• Mononucleosis
  • Mono can present with multiple small red spots (petechia) on the hard palate.

Image source: https://cdn.ymaws.com/www.aocd.org/resource/resmgr/Meeting_Resources/2015FallMeeting/Syllabus/lewisgale15.pdf

• Early HIV
  • Early HIV can cause multiple painful oral ulcers that are shallow with well-defined borders and a white base.

Image source: HIV: Symptoms That Affect Your Whole Body. https://www.webmd.com/hiv-aids/ss/slideshow-hiv-effects.

Rash

Both conditions can present with a rash, but rash is more common with the acute retroviral syndrome of early HIV.

• Mononucleosis
  • It is not very common to get rash with mono, but when it does appear it is similar to the rash of a drug allergy, morbilliform in appearance.

Image source: Cohen JI (2008). "Epstein-Barr Infections, Including Infectious Mononucleosis". In Kasper DL, Braunwald E, Fauci AS, Hauser SL, Longo DL, Jameson JL, Loscalzo J (eds.). Harrison's principles of internal medicine (17th ed.). New York: McGraw-Hill Medical Publishing Division. pp. 380–91.

Early HIV

Rash is a common symptom in early HIV, and it can cover the entire body, including the palms, soles, and scalp. The most commonly affected areas are the neck and chest. It is mildly itchy. Rash usually appears 48 hours after the onset of fever and self-resolves in a week’s time. The rash usually consists of well-defined red or pink spots

Image source: U.S. National Library of Medicine / National Institutes of Health

Symptom resolution

• Symptom resolution for mono can take a bit longer than it does for early HIV.
• Mononucleosis: 2–4 weeks, with fatigue persisting up to 6 months
• Early HIV: 1–2 weeks

Other important signs to consider

• Mononucleosis, unlike early HIV, can cause enlarged liver and spleen
• HIV can present with diarrhea in addition to URI symptoms
• Both conditions can result in positive heterophile ab and monospot tests
• Atypical lymphocytes are elevated in both, with the number going higher in mono

Flu vs. early HIV

Here you will learn the difference between flu and early retroviral syndrome from a doctor’s point of view.

Flu is a common condition that affects many people during flu season. It is usually a self-limiting condition, unlike early retroviral syndrome, which needs to be differentiated from flu and treated with HIV-specific medication.

Signs and symptoms such as fever, headache, rash, and sore throat can occur with both conditions. So, to distinguish the two conditions, it’s important to analyze signs and symptoms within the right context. That means the doctor must consider the following:

• What preceded the event (a new sexual partner or close contact with someone with flu, for example)
• How the disease is evolving over time
• Any additional signs and symptoms

Here we summarize the main differences that must be considered when comparing flu to early retroviral syndrome. As in other sections, a table containing facts will be followed by frequently asked questions answered by Dr. F.

Prevalence

The table below summarizes US statistics regarding newly diagnosed cases of flu and acute retroviral syndrome ear year. Knowing these numbers is important because they show how common each condition is, and that helps us begin to have an understanding of which condition, in general, is more likely. Obviously, we must look at other information to be more precise.

Signs and symptoms: differences and similarities

Incubation period

The incubation period is the time after exposure before symptoms appear.

• Flu: 2 days, on average
• HIV: 2–4 weeks

Speed of disease onset

The onset of both HIV and flu is sudden. This means that most of the symptoms appear at the same time and build up fast.

Fatigue

Both flu and early HIV can present with fatigue, usually a familiar fatigue, not something you’ve never felt before.

Sore throat

Both conditions present with sore throat, but early HIV has more significant signs and symptoms.

• Flu
  • Minimal throat redness and swelling
• Early HIV
  • Tonsillar enlargement without redness and white patches

Lymph node enlargement

Flu, unlike early HIV, does not present with significant lymph node enlargement.

• Flu
  • No significant lymph node enlargement
• Early HIV
  • In addition to neck and armpit lymph node enlargement, early HIV can cause enlargement in other areas as well. It’s usually not tender to the touch. Lymph nodes become enlarged during the second week and get better over time. They can remain enlarged even after the initial symptoms are gone.

Weight loss

Both conditions can suppress appetite, but this is much more significant with HIV than with flu.

• Flu
  • Appetite is minimally suppressed, and it doesn’t affect the patient’s weight.
• HIV
  • Appetite suppression with HIV is more significant and can result in significant weigh loss (the average weight loss with HIV is 6 kg or 13 lbs.).

Headache

Headache is a very nonspecific symptoms that occurs with both conditions, but with early HIV it’s stronger and affects a specific location.

• Flu

Generalized headache for the first few days

• Early HIV

Headache with early HIV is more severe, located in the orbital area (eye area), and gets worse with eye movement.

Oral lesions

Painful oral sores are a very distinctive feature of early HIV infection.

• Flu
  • Oral lesions are not common with flu unless the patient has a chancre sore secondary to suppressed immune system at the same time.
• Early HIV
  • Early HIV can cause multiple painful oral ulcers that are shallow with well-defined borders and a white base.

Rash

Rash is a common symptom with HIV and can be a distinctive feature in combination with other context information, such as recent new sexual contact, flu-like symptoms, weight loss, and timing of symptoms suggestive of HIV.

• Flu
  • Rash is very unlikely to be due to flu.
• Early HIV
  • Rash is a common symptom in early HIV, and it can cover the entire body, including the palms, soles, and scalp. The most commonly affected areas are the neck and chest. It’s mildly itchy. Rash usually appears 48 hours after the onset of fever and self-resolves in a week’s time. The rash usually consists of well-defined red or pink spots.

Symptom resolution

• Flu symptoms last 5–7 days.
• Early HIV symptoms resolve 1–2 weeks after exposure.

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