Viral Infections Blood Test

What is Viral Infections?

Viral infections are illnesses caused by viruses that invade and replicate inside the body's cells, affecting various organs and systems. They are caused by pathogens including influenza virus, Epstein-Barr virus, cytomegalovirus, and many other viral agents that trigger immune responses. The Complete Blood Count with Differential is the most important test for viral infections because it measures lymphocyte levels that elevate when the body fights viral invaders.

RECOMMENDED TEST Complete Blood Count / CBC (includes Differential and Platelets)
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Fast & easy, results by email & SMS
No extra fees paid at the lab
No need to visit a doctor
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No insurance needed
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What causes viral infections?

Viral infections are caused by pathogenic viruses that invade living cells and hijack cellular machinery to replicate. Common viral agents include influenza virus, rhinovirus (common cold), Epstein-Barr virus (EBV), cytomegalovirus (CMV), respiratory syncytial virus (RSV), and coronaviruses. These microscopic infectious agents enter the body through respiratory droplets, direct contact, contaminated surfaces, or bodily fluids, then penetrate cells to reproduce and spread throughout the body, triggering immune system responses that produce the symptoms you experience during illness.

What is the best test for viral infections?

The Complete Blood Count with Differential is the most important test for viral infections because it reveals elevated lymphocyte levels, which are white blood cells that increase specifically when your body fights viral invaders. This test provides a comprehensive picture of your immune response by measuring all blood cell types and identifying characteristic patterns of viral activity. The Lymphocyte Subset Panel 4 (CD4:CD8 Ratio Profile) is an essential supplementary test that detects specific viral infections like cytomegalovirus and Epstein-Barr virus by analyzing immune cell populations and CD8+ levels. For certain viral conditions, the ANA Screen IFA can identify immune responses indicating current or past infections when specific viral tests are unavailable.

When should I get tested for viral infections?

You should get tested if you experience persistent fever lasting more than three days, extreme fatigue that interferes with daily activities, swollen lymph nodes in your neck or armpits, unexplained body aches and chills, or symptoms that worsen instead of improving after several days. Testing is especially important if you have a weakened immune system, are pregnant, or have been exposed to someone with a confirmed viral infection. Early testing helps identify the infection type, monitors your immune response, and determines if your body is fighting the virus effectively or if complications are developing.

What are the symptoms of viral infections?
Viral infections typically cause fever, fatigue, body aches, headache, sore throat, cough, runny nose, and general malaise. Depending on the specific virus and affected body system, you might experience additional symptoms like nausea, vomiting, diarrhea, skin rashes, swollen lymph nodes, or difficulty breathing. Symptoms usually develop gradually as the virus replicates and your immune system responds, with most viral infections producing noticeable effects within 1-3 days of exposure. The severity and duration vary based on the virus type, your immune system strength, and overall health status.
Who is at risk for viral infections?
Everyone is susceptible to viral infections, but certain groups face higher risk including young children with developing immune systems, older adults over 65, pregnant women, and individuals with compromised immunity due to conditions like HIV, diabetes, or cancer treatments. People who work in healthcare settings, schools, or daycare facilities have increased exposure risk. Additional risk factors include living in crowded conditions, inadequate sleep, chronic stress, poor nutrition, lack of vaccination, and close contact with infected individuals. Those with chronic respiratory conditions like asthma or COPD are more vulnerable to severe viral infections affecting the lungs.
What happens if viral infections are left untreated?
Untreated viral infections can lead to serious complications including bacterial superinfections (like pneumonia or sinusitis), dehydration from persistent fever and fluid loss, and organ damage when viruses spread throughout the body. Some viral infections can become chronic, causing long-term health problems such as chronic fatigue syndrome, heart inflammation (myocarditis), or neurological complications. In vulnerable populations like infants, elderly individuals, or immunocompromised people, untreated viral infections can progress to life-threatening conditions requiring hospitalization. Certain viruses can also reactivate later in life, causing recurrent symptoms or different disease manifestations.
Can viral infections be diagnosed with a blood test?
Yes, blood tests effectively diagnose viral infections by detecting your immune system's response to viral invaders. The Complete Blood Count reveals elevated lymphocyte levels that specifically indicate viral activity, while specialized tests like the Lymphocyte Subset Panel measure specific immune cell populations affected by viruses like cytomegalovirus and Epstein-Barr virus. Blood tests can also identify antibodies your body produces against specific viruses, detect viral genetic material or proteins, and assess how the infection impacts overall health through changes in blood cell counts and immune markers. These tests help confirm viral infections, distinguish them from bacterial infections, and monitor recovery progress.
How are viral infections treated?
Most viral infections are treated with supportive care including rest, adequate hydration, fever reducers like acetaminophen or ibuprofen, and symptom management while your immune system fights the virus. Antiviral medications are available for specific viral infections like influenza (oseltamivir), herpes viruses (acyclovir), and hepatitis (interferon), which work by stopping viral replication or reducing symptom severity. Treatment focuses on preventing complications, supporting immune function, and addressing secondary bacterial infections if they develop. Severe viral infections may require hospitalization for intravenous fluids, oxygen therapy, or intensive monitoring, particularly in high-risk individuals.
How can I prevent viral infections?
Prevent viral infections by practicing frequent handwashing with soap and water for at least 20 seconds, avoiding close contact with sick individuals, and keeping your hands away from your face. Stay current with vaccinations including annual flu shots and other recommended vaccines based on age and health status. Strengthen your immune system through adequate sleep (7-9 hours nightly), regular exercise, stress management, and a nutrient-rich diet high in fruits and vegetables. Disinfect frequently-touched surfaces, avoid sharing personal items like utensils or towels, cover coughs and sneezes, and stay home when sick to prevent spreading infections to others.
What natural remedies help with viral infections?
Natural remedies that support recovery from viral infections include vitamin C from citrus fruits and supplements (500-1000mg daily) to boost immune function, zinc lozenges within 24 hours of symptom onset to reduce duration, and elderberry extract which has antiviral properties. Drink warm fluids like herbal teas with honey and lemon to soothe throat irritation and maintain hydration. Probiotics support gut health where much of your immune system resides, while garlic contains allicin with natural antiviral effects. Adequate rest is the most powerful natural remedy, allowing your body to dedicate energy to fighting the infection. Use a humidifier to ease respiratory symptoms and practice gentle activities like walking to maintain circulation without overexertion.
How’s this work?
Getting your blood test with us is easy, private & backed by the power of science.

Long story short:
  1. In the test options, use the filters or search box to narrow your choices and find the test you want.
  2. If you need a hand navigating through options, text our super friendly support team at 754-799-7833, and we'll provide tailored suggestions to help you find the ideal test.
  3. Once your order is placed, we’ll create your doctor’s lab order remotely, without any need for you to make a trip to a doctor in person or to talk to the doctor. Expect to receive your doctor’s lab order right in your inbox. It will also be in your patient portal if you need to find it later. We’ll also include instructions regarding fasting and other requirements for your test. Your patient portal will be auto-created hassle-free during checkout.
  4. If this is your first time ordering, you'll be prompted to create a password for instant login access to your patient portal. It's a quick way to conveniently access your orders and results whenever you want.
  5. When you’re ready, visit one of our 4,000 locations. Just bring your ID – no printing or faxing of your lab order is needed, as your order and details will already be in the lab system.
  6. Note that most lab locations don’t accept walk-ins, so it’s best to book an appointment in advance. Don’t worry – we’ll provide detailed instructions along the way.
  7. You’ll get your results via email & SMS and dive into understanding your body better. Yup, that easy!
  8. If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com and we'll gladly help you.
How do I know which test to get?
In the test options, find the test you want. If you’re not sure which test to get, we can lend a hand in finding the right option.

Just text or call us at 754-799-7833, email us at support@privatemdlabs.com, and we'll gladly help you. We've got your back and reply quickly.
Is it possible to make changes to my lab order if I made a mistake with the name, date of birth, or any other details?
Absolutely! We totally understand that errors can happen. No worries, we're here to help you.

Just reach out to us via text at 754-799-7833 or shoot us an email at support@privatemdlabs.com. Remember to include your order number and let us know the correct information you’d like to update. Our awesome team will jump right in and make sure everything is sorted out and accurate for you.

There are no changes necessary if your address is wrong on the requisition though. We don’t mail anything out.

Our lab requires an address to be listed to generate an order.
Do you accept health insurance?
Only HSA & FSA is accepted.

Our services are strictly self-pay and cannot be submitted to your health insurance provider except for Health Savings Accounts or Flexible Savings Accounts.

This policy applies to all insurance companies, including federal health insurance programs like Medicare.

If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com.
Can I cancel my order?
Yes.

We get it – sometimes your needs change.

As long as your samples haven’t been collected yet, we’re happy to help you cancel your order.

If you have any further questions, please text us at 754-799-7833 or email support@privatemdlabs.com.

You can read more about our cancellation policy here.
How can I find a lab location near me?
During the ordering process, you’ll be able to select a specific lab near you, with no strings attached! You can switch it up later easily and visit any of our authorized locations as long as it’s the same lab company you selected your test for (Quest Diagnostics or Labcorp).

Before you proceed with your order, feel free to browse through all our lab locations here. This will give you the peace of mind of knowing that there's a lab nearby your home, office or your favorite gym.

If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com and we'll gladly help you.
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* Regular blood test results (e.g., CBC) typically start arriving the next business day after sample collection. More complex tests, such as hormone panels, may take up to 10–15 business days due to their complexity.

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Complete Blood Count / CBC (includes Differential and Platelets)
What's included
Fast & easy, results by email & SMS
No need to visit a doctor
Private & confidential
No insurance needed
Results explained
No extra fees paid at the lab

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