• Published on: Sep 01, 2021
  • 3 minute read
  • By: Second Medic Expert

Why Do We Need Two Doses Of Vaccine?

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Why do we need two doses of vaccine?

Vaccination is a two-fold protective measure for preventing illness. The first dose alerts the immune system to the presence of a certain virus or bacterium, and it creates a cellular immunity of sorts. The second dose is required to alert the body's antibodies, which are typically slower acting but more powerful bodies of defenses. These antibodies present themselves naturally in our bodies after vaccination, forming what we know as "natural specific immunity." To get that natural specific immunity from your second vaccination shot, you will need both injections at least six weeks apart. Essentially then, getting vaccinated twice in quick succession has no effect on your ability to build up natural specific immunity because you'll already be protected by cellular-specific immunity when you receive your second one.

The second dose helps to reduce the incidence of infectious disease. A major reason for a second dose is "herd immunity," in which a high proportion of people within a population have been vaccinated to provide what is known as "community protection" against an infection's spread. This limits the number of individuals who might otherwise be vulnerable or susceptible to contracting and transmitting infection. For this reason, everyone needs to do their part in making sure their own vaccinations are up-to-date and take care does not infect others when they're around them with compromised immune systems--primarily infants too young to have ever been vaccinated or anyone who cannot get vaccines for medical reasons such as being immunosuppressed.

The second dose of the vaccine introduces a different version of the virus into your system to allow your body to develop an immunity because not all viruses are 100% susceptible to the first vaccine.

The effectiveness of vaccination does decline over time, so another injection can help prolong immunity for 5-6 years before it's necessary to vaccinate again. It may be because there are different versions or "strains" or versions of viruses that vaccines don't always work well on. Or there are definitions for "immunity" that are different from ours - whether you have antibodies in your blood doesn't always show true protection against an infection! Of course, we recommend asking a medical professional if you're really interested in this question.

Reason #1: Whether an individual had natural immunity previously. The first shot could wear off for some people, so the second dose ensures that there is protection long after the first dose has worn off.

Reason #2: Some children do not develop strong enough immunity when given just one vaccine dose or they received their vaccines too early in life and later required a booster shot so the best way to protect them is with two doses.

Third Medic Medical consultation online To improve chances of inducing protective immunity in unvaccinated groups during outbreaks, it may be advisable to administer two doses of vaccines to maximize coverage among these populations The cold virus mutates extremely rapidly, and your chances of contracting a mutated strain of cold virus from the vaccine are higher if you skipped the first round. The goal here is to vaccinate as many people as possible with a vaccine that is most likely going to protect them from infection. That’s because even if 50% of those vaccinated this year will not be protected from contracting the disease, that 50% who do end up not being able to contract it are still more protected than they would have been had there been no vaccination. If you argue that vaccines don't work, then you are arguing that children should go untreated for deadly diseases because populations can never get rid of all illnesses at once!

This is a two-fold concern. First, we're aiming to create immunity against the disease more rapidly and it appears that this isn't accurate if we only vaccinate once; we need to boost with two doses at least one month apart. Second, because there are limitations in the science behind vaccination, it's difficult to tell who will have the highest reaction or reaction frequency. So for absolute safety, most doctors recommend three doses at any point in life for those who've never been vaccinated before

Second dose of the vaccine is to confer "immunity." If you happen to be exposed to a virus or bacteria and recover, your body will remember and create antibodies for that specific infection. A second dose of the vaccine provides enough time for those immunities to build up.

If you take the first dose, and go out right afterward to play with friends--this could lead the immune system into mistakenly attacking your own tissues as if they were infected as well because it doesn't yet know not them as healthy tissue.

The first dose is more or less a "primer" and the second dose corresponds with the timing of the typical infectious disease infection. Estimating how long it takes for immunity to develop also depends on which vaccine is being administered. Different viruses elicit variable immune responses, which means that they need different types of vaccines to work best. It's been found, for instance, that most people who receive an influenza vaccination require two doses about four weeks apart to fight off the flu properly. In addition, live attenuated influenza vaccine spurs fewer immunological side effects because it contains weakened versions of elements from virus strains already circulating among humans – since those factors are weaker than their intact counterparts found in a regular flu shot or nasal spray.

The two-dose vaccine regimen is a tried and tested method showing excellent effectiveness.

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Insufficient water intake

How Poor Hydration Affects Joint Health: Why Water Matters for Mobility

Water is essential for nearly every function in the human body, yet many people underestimate its importance for joint health. While hydration is commonly associated with digestion and skin health, it also plays a crucial role in maintaining smooth and pain-free joint movement.

Understanding how poor hydration affects joint health can help prevent stiffness, discomfort and long-term mobility issues.

 

The Role of Water in Joint Function

Joints are where two bones meet, allowing movement and flexibility. Healthy joints rely on:

  • Cartilage
     

  • Synovial fluid
     

  • Ligaments
     

  • Tendons
     

Cartilage, which cushions bones, contains a high percentage of water. Synovial fluid acts as a lubricant, reducing friction during movement.

Proper hydration ensures these components function effectively.

 

What Happens When You Are Dehydrated?

When the body lacks sufficient water:

  • Synovial fluid production may decrease
     

  • Cartilage may lose elasticity
     

  • Joint cushioning becomes less effective
     

This can result in stiffness and discomfort.

 

1. Reduced Joint Lubrication

Synovial fluid requires adequate hydration to maintain volume and viscosity.

Without enough water:

  • Friction between bones increases
     

  • Movement becomes less smooth
     

  • Risk of wear and tear rises
     

 

2. Increased Joint Stiffness

Dehydration may cause joints to feel tight, especially:

  • In the morning
     

  • After prolonged sitting
     

  • During physical activity
     

Stiffness may limit flexibility.

 

3. Higher Risk of Injury

Poorly lubricated joints may be more prone to:

  • Sprains
     

  • Strains
     

  • Cartilage damage
     

Hydration supports tissue resilience.

 

4. Worsening of Existing Joint Conditions

Individuals with conditions such as osteoarthritis may experience increased discomfort if hydration is inadequate.

While water does not cure arthritis, it supports overall joint function.

 

5. Reduced Nutrient Delivery

Water helps transport nutrients to joint tissues.

Dehydration may impair circulation and nutrient exchange, slowing tissue repair.

 

Signs of Dehydration That May Affect Joints

  • Dry mouth
     

  • Dark urine
     

  • Fatigue
     

  • Headaches
     

  • Muscle cramps
     

  • Joint stiffness
     

Recognizing early dehydration signs prevents complications.

 

How Much Water Do You Need?

Hydration needs vary depending on:

  • Body weight
     

  • Climate
     

  • Physical activity level
     

  • Health conditions
     

On average, adults may require 2–3 liters of water daily.

In hot climates such as India, higher intake may be necessary due to increased sweating.

 

Tips to Maintain Proper Hydration

1. Drink Water Regularly

Do not wait until you feel thirsty.

 

2. Eat Water-Rich Foods

Include:

  • Cucumbers
     

  • Watermelon
     

  • Oranges
     

  • Tomatoes
     

 

3. Limit Excessive Caffeine and Alcohol

These may contribute to fluid loss.

 

4. Carry a Water Bottle

Keeping water accessible encourages consistent intake.

5. Hydrate Before and After Exercise

Physical activity increases fluid loss through sweat.

 

Hydration and Joint Health in India

In India’s hot and humid climate, dehydration is common, especially during summer months.

Outdoor workers, athletes and elderly individuals are particularly vulnerable.

Maintaining adequate hydration supports not only joint health but overall wellbeing.

 

When to Consult a Doctor

Seek medical advice if you experience:

  • Persistent joint pain
     

  • Swelling
     

  • Limited range of motion
     

  • Redness or warmth around joints
     

These may indicate underlying joint disorders requiring evaluation.

 

Conclusion

Poor hydration can negatively affect joint health by reducing lubrication, increasing stiffness and raising injury risk. Since cartilage and synovial fluid depend heavily on water, maintaining adequate hydration is essential for smooth movement and long-term mobility.

Drinking sufficient water daily is a simple yet powerful step toward protecting joint health. Combined with regular exercise and balanced nutrition, proper hydration supports active and pain-free living.

Small daily hydration habits can make a significant difference in how your joints feel and function.

 

References

  • Indian Council of Medical Research – Hydration Guidelines

  • World Health Organization – Water and Health Resources

  • Indian Journal of Orthopaedics – Joint Health Studies

  • National Institute of Nutrition India – Fluid Intake Recommendations

  • Journal of Sports Medicine – Hydration and Musculoskeletal Health Research

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