• Published on: Apr 20, 2020
  • 3 minute read
  • By: Dr Rajan Choudhary

Is Herd Immunity A Valid Strategy For COVID 19?

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Yesterday we explained you what Herd Immunity means and how it works, today we will take the discussion further to determine whether it is effective and can be recommended in the current context. 

COVID-19 currently does not have a cure or a vaccine. Lockdown is the only strategy that appears to be working. Could implementing policies that encourages herd immunity be used to accelerate immunity in the population without the need for a vaccine?

  1. INFECTIVITY

For the strategy to work we need to know a few things about the virus. How infective is it? In one of our earliest blogs we discussed infectivity at length and determined that the R0 (infectivity) may be between 2 and 3. This means each person with the virus can infect around 2-3 people at a time. Whilst this is not as high as Mumps (10-12) it is much higher than the common flu. The higher the R0 the more people that need to be immunised before herd immunity is achieved. For COVID it is estimated that 70% of the population need to be infected.

This is based off our current testing. Due to shortages in testing kits, only testing those that have a high likelihood of being infected and poorly organised testing infrastructure in some countries, we are likely underestimating. The number of people infected may be much higher as we are missing those that are asymptomatic but still have the disease and are still passing the disease on.

  1. MORTALITY

Secondly, we need to know the mortality from COVID-19. Early estimates of mortality were as high as 10%, as we had little data on how many people were truly infected, but as the number of infected cases rose, and testing amongst the infected and symptomatic population rose, a more accurate mortality has been found to be around 1%. There is a risk we may still be underestimating the true mortality, as some cities have noted a spike in cardiac deaths, and some evidence supports possible cardiac damage due to COVID. But from the data we have, we know its mortality is lower than MERS (34%) and SARS (10%) but more than influenza (0.1%).

estimates of the COVID-19 case fatality rate

Whilst we have some data on who is likely to suffer from severe COVID symptoms (elderly, immunocompromised, people with heart or lung problems) we still cannot accurately determine who will get severe COVID in the “low risk” population. Simply because someone is young and healthy does not mean they will not die from COVID.

  1. LENGTH OF IMMUNITY

Third we need to know how long this immunity will last. Similar coronaviruses responsible for the common cold usually create immunity that lasts for a few months, which is why we often get the cold repeatedly. A virus is also very prone to mutations that can change the structure and functions of its proteins, proteins responsible for tagging, latching on to and entering cells. If the structure of these proteins changes enough, then our antibodies will not be able to bind on, and new types of antibodies will have to be made with a slightly different structure. This effectively means our bodies have to start from step 1 again to create immunity, and we have to make new vaccines. This mutation rate is why we have to make new vaccines every season for the flu.

  1. LONG TERM COMPLICATIONS

Finally, we need to know if there are any long-term implications from a viral infection. Again, this is something we do not know yet, as the virus has only been around for a few months. There may be implications for the cardiovascular system, long term breathing problems or more. And even if the complication rate appears relatively low (say, 1%), if millions of people are allowed to get infected, by definitions thousands or tens of thousands of people will have these complications, complications that can lead to issues later in life or an early death.

CONCLUSION

So, is herd immunity a viable strategy for COVID? Without a safe vaccine the general consensus appears to be no.

We don’t know how infective the virus really is or how many people it has infected

A    1%     death rate is still very high. This means for every 100 people to be infected; one will die. This would mean hundreds of thousands of people dead in a country with a population over 10 million. It is unacceptably high.

If the death rate is 1%, then hospitalisation rate is likely higher. Almost all countries do not have capacity to have 1% of the population in hospital. Overwhelming the healthcare system will lead to poorer care, and worse care for those who do not have COVID. Leading to more people coming to serious harm or dying as a result of poor healthcare, not because of COVID.

We don’t know the long-term effects of COVID. By purposefully infecting people instead of waiting for a vaccine we may be causing unnecessary damage to a person’s health that only becomes apparent later in life. But this is speculation as we do not currently know if COVID has long term effects,

We don’t know if all of the risks above will amount to anything. The immunity may not last long enough, leading to another spike in infections and mortality.

Mass vaccination appears to be the safest strategy. And though human clinical trials have started on a number of vaccines, we are still months away from deployment.  Until then we should not come out of lockdown prematurely, not until we have received an unbiased assessment from public health officials that states it is safe.

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Lipid Profile Test

Lipid Profile Test – Normal Range and Risks

Keeping your heart healthy isn’t just about staying active or eating green veggies. It also means knowing what’s going on inside your body—especially your cholesterol levels. One of the best ways to track this is through a lipid profile test.

If you’re wondering what this test means, what the numbers should be, and what risks you face if they're abnormal—this blog is for you.

Let’s dive into lipid profile test – normal range and risks in easy and clear language.

 

What Is a Lipid Profile Test?

A lipid profile test is a blood test that measures the amount of fat (lipids) in your blood. These lipids include different types of cholesterol and triglycerides.

The test helps evaluate your risk of heart disease, stroke, and clogged arteries.

 

What Does the Lipid Profile Test Measure?

A complete lipid profile usually measures:

  1. Total Cholesterol – the overall amount of cholesterol in your blood
     

  2. LDL (Low-Density Lipoprotein) – the “bad” cholesterol that can block arteries
     

  3. HDL (High-Density Lipoprotein) – the “good” cholesterol that protects your heart
     

  4. Triglycerides – a type of fat that provides energy but can cause heart issues in high amounts
     

Sometimes, the test also calculates VLDL and a cholesterol/HDL ratio to better assess your health risks.

 

Lipid Profile – Normal Range

Understanding what your numbers mean is key. Here are the recommended normal ranges:

Test Component

Normal Range

Total Cholesterol

Less than 200 mg/dL

LDL (Bad Cholesterol)

Less than 100 mg/dL

HDL (Good Cholesterol)

40 mg/dL or more (men), 50+ (women)

Triglycerides

Less than 150 mg/dL

Note: Values may vary slightly depending on labs and age. Always consult your doctor for interpretation.

 

Why Is This Test Important?

High cholesterol usually shows no symptoms. That’s why it's called a silent threat.

Your arteries may slowly get clogged without you knowing it, increasing the risk of:

  • Heart attacks
     

  • Strokes
     

  • Peripheral artery disease
     

  • High blood pressure
     

A lipid profile gives an early warning so you can make timely changes to protect your heart.

 

Risks of Abnormal Lipid Profile

Here’s what happens when the results are not in the normal range:

High LDL Cholesterol

  • Builds plaque in your arteries
     

  • Increases risk of heart attack or stroke
     

Low HDL Cholesterol

  • Reduces protection for your heart
     

  • Makes it easier for bad cholesterol to stick to artery walls
     

High Triglycerides

  • Can lead to pancreatitis and diabetes
     

  • Often linked with obesity and poor lifestyle
     

High Total Cholesterol

  • General risk marker for cardiovascular diseases
     

 

Causes of High Cholesterol or Triglycerides

  • Unhealthy diet (high in fried, fatty, and sugary foods)
     

  • Lack of physical activity
     

  • Smoking and alcohol consumption
     

  • Obesity
     

  • Diabetes or thyroid problems
     

  • Genetic/family history of high cholesterol
     

 

How to Improve Your Lipid Profile Naturally

If your test results are abnormal, you don’t always need medicine right away. Often, small changes in your lifestyle can bring big improvements.

Eat a Heart-Healthy Diet

  • Choose whole grains, fruits, vegetables, and lean proteins
     

  • Avoid processed food, red meat, and fried items
     

  • Include omega-3 rich foods like fish, flaxseeds, and walnuts
     

Exercise Regularly

  • 30 minutes of walking, yoga, cycling, or swimming at least 5 days a week
     

Quit Smoking & Limit Alcohol

  • These habits lower HDL and increase LDL
     

Maintain a Healthy Weight

  • Losing even 5–10% of body weight can improve lipid levels
     

 

How and When to Take the Lipid Profile Test

When to Take:

  • Once every 12 months for adults above 30
     

  • More often if you have heart disease, diabetes, obesity, or a family history
     

Fasting Required?

Yes, you should fast for 8–12 hours before giving the blood sample for the most accurate results.

 

Can I Get This Test at Home?

Yes! Platforms like SecondMedic.com offer home sample collection for the Lipid Profile Test, powered by trusted labs like Thyrocare.

You just book the test online, and a technician collects the sample from your doorstep. Results are available digitally within 24–48 hours.

Total cholesterol over 240 mg/dL, LDL over 160 mg/dL, and triglycerides over 200 mg/dL are considered high-risk levels.

 

Conclusion

A lipid profile test is a simple yet powerful tool that gives deep insights into your heart health. Knowing the normal range and understanding the risks of abnormal levels can help you take control early and live a longer, healthier life.

Stay proactive about your health. Book a lipid profile test – normal range and risks checkup today and make heart-smart choices.

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