• Published on: Apr 04, 2020
  • 3 minute read
  • By: Dr Rajan Choudhary

Developing A Vaccine For COVID-19? Part 1

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It is often stated vaccination has made the greatest contribution to global health of any human discovery, other than clean water and sanitation, and their impact on everyday life is immediately evident. We have managed to completely eradicate two major infections from existence (smallpox and rinderpest) , and the WHO are working towards adding polio to that list.

In these cases the numbers speak for themselves. It is estimated that the eradication of smallpox in 1980 has saved 5 million lives per year, adding up to 150 to 200 million by 2018. Common vaccination programmes for polio, measles, mumps, rubella, rabies and hepatitis A have prevented nearly 200 million cases from occurring in the US alone over the past 50 years, and 4.5 billion instances of the diseases worldwide.

We have achieved a 99% immunisation rate against polio, preventing children from suffering crippling paralysis, and only 3 countries remain. Sadly, around 1.4 million children under 5 still die from preventable diseases each year as they do not have access to these life saving vaccines, but charities and public health organisations around the world are working hard to improve access.

So what are vaccines? And how will they help is in the face of the latest pandemic? Here we will go into the challenges behind making vaccines, and why a vaccine against COVID-19 is unlikely to be ready in the next few months, or even this year.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4024226/ contribution of vaccination

https://www.who.int/features/factfiles/polio/en/ polio eradication

https://www.sciencedaily.com/releases/2017/03/170303163208.htm study article

WHAT IS A VACCINE

The human body’s immune system is incredibly smart. It is able to distinguish between infective organisms, such as bacteria, viruses and parasites, from our own body’s cells, target these invaders for destruction and keep our bodies healthy. Even better, the body remembers any previous infections it has had before, recognise these previous infections even quicker and even eradicate the disease before we know we are infected.

Vaccines target the immune system’s memory by presenting them with pieces of these infective diseases. The small amounts do not cause any infective symptoms, but if the person is infected later in life their body will mount a quicker response and prevent them from falling ill. These vaccines can contain broken up parts of the organisms, “dead” organisms or “live” versions that have been severely weakened so they cannot cause any harm.

In summary, medicines treat us when we get an infection. Vaccines make sure we never suffer from an infection in the first place.

https://www.chop.edu/centers-programs/vaccine-education-center/making-vaccines/how-are-vaccines-made Making Vaccines

THE HURDLES WE FACE IN RESEARCH

Making a vaccine is a difficult process, one that can take 3–5 years and cost hundreds of millions of dollars, sometimes billions of dollars. This is because there are many difficult steps to be taken in the process of creating a vaccine that is effective, but more importantly one that is safe.

To start with the troubling organism has to be identified. For COVID-19 it took a few weeks to recognise the virus responsible, and some time more to understand its genetic code and grow the virus in lab conditions. We then have to understand the virus, how it infects, how it causes symptoms, and how it has mutated compared to the coronaviruses responsible for SARS and MERS.

After this, we have to isolate parts of the virus our immune system will recognise. This is usually the outside coat of the virus. The DNA responsible for making these parts need to be found in the virus’ genetic code, and put inside other “skeleton” viruses. This will force the dummy virus to look like coronavirus, without the ability to infect and kill someone.

These dummy viruses can be injected into animals to see if it causes an immune reaction, whether the immune system recognises it as the coronavirus responsible for COVID-19, and whether it will protect the animal from the real COVID-19. Up to now the research has likely cost a few million dollars. The next step is when the price inflates up to billions.

If the vaccine appears safe in animals, it can be tested in humans. This can be dangerous at first, since we don’t know whether a vaccine that works in an animal will work in a human. And we don’t know if there will be any side effects to the vaccine. Human testing has to be very thorough, very careful, and safe for use. If you give too much of the virus it might make the person sick, too little and it wont immunise the person. These clinical trials can take years, and if the vaccine fails at this point its back to the drawing board, to try another step.

https://www.theatlantic.com/politics/archive/2014/10/how-to-make-an-ebola-vaccine-5-simplified-steps/454443/ ebola vaccine

Now we have a basic understanding of what vaccines are and why it takes so long to make a vaccine. In the next part we will look at why viral vaccines can cause even more problems, and how far we have come with the COVID-19 vaccine,

Dr Rajan Choudhary, London UK

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Vitamin D

Vitamin D Deficiency Symptoms: Signs Your Body May Be Lacking Vitamin D

Vitamin D is an essential nutrient that plays a vital role in maintaining strong bones, supporting the immune system and regulating several important functions in the body. Despite its importance, vitamin D deficiency is one of the most common nutritional deficiencies worldwide.

In India, vitamin D deficiency has become increasingly prevalent due to lifestyle factors such as limited sunlight exposure, indoor working environments and dietary habits. According to the Indian Council of Medical Research (ICMR), a significant percentage of the population may have insufficient vitamin D levels.

Recognizing the symptoms of vitamin D deficiency early is important because prolonged deficiency can lead to serious health complications affecting bones, muscles and overall wellbeing.

What Is Vitamin D and Why Is It Important?

Vitamin D is often called the “sunshine vitamin” because the body produces it when the skin is exposed to sunlight. It plays a key role in calcium absorption, which is essential for maintaining healthy bones and teeth.

In addition to bone health, vitamin D supports several important functions including:

immune system regulation
muscle function
inflammation control
hormonal balance

Low levels of vitamin D can disrupt these functions and contribute to various health problems.

Common Symptoms of Vitamin D Deficiency

Vitamin D deficiency can manifest through several symptoms, many of which are often overlooked or mistaken for other health issues.

Persistent Fatigue

Constant tiredness or low energy levels may be one of the earliest signs of vitamin D deficiency. Even after adequate rest, individuals with low vitamin D levels may continue to feel exhausted.

Vitamin D plays a role in cellular energy production, and insufficient levels may contribute to chronic fatigue.

Bone and Back Pain

One of the most well-known effects of vitamin D deficiency is bone discomfort. Vitamin D helps the body absorb calcium, which is essential for maintaining bone strength.

Low vitamin D levels may cause:

bone pain
lower back pain
increased risk of fractures

Persistent bone discomfort should be evaluated by a healthcare professional.

Muscle Weakness

Vitamin D is important for muscle health and function. Deficiency can lead to muscle weakness, cramps or general muscle fatigue.

Older adults with vitamin D deficiency may also experience reduced mobility and increased risk of falls.

Frequent Illness or Infections

Vitamin D plays a key role in supporting the immune system. Individuals with low vitamin D levels may experience frequent colds, infections or slower recovery from illness.

Research suggests that adequate vitamin D levels help strengthen immune defenses against respiratory infections.

Mood Changes and Depression

Vitamin D may influence brain function and mood regulation. Some studies have found a connection between low vitamin D levels and mood disorders such as depression or anxiety.

People experiencing persistent mood changes should consider evaluating vitamin levels as part of a broader health assessment.

Hair Loss

Severe vitamin D deficiency may contribute to hair thinning or hair loss. While hair loss can have multiple causes, nutritional deficiencies including vitamin D deficiency may play a role.

Slow Wound Healing

Vitamin D contributes to the body’s inflammatory response and tissue repair processes. Individuals with deficiency may notice slower wound healing or delayed recovery from injuries.

Who Is at Risk of Vitamin D Deficiency?

Several factors can increase the risk of vitamin D deficiency.

Limited Sun Exposure

People who spend most of their time indoors or use strong sun protection regularly may not receive enough sunlight to produce sufficient vitamin D.

Urban lifestyles and indoor work environments contribute to this problem.

Older Adults

As people age, the skin becomes less efficient at producing vitamin D from sunlight. Older adults may therefore require additional dietary intake or supplements.

Individuals with Darker Skin

Melanin reduces the skin’s ability to produce vitamin D from sunlight. Individuals with darker skin tones may require longer sun exposure to produce adequate levels.

Poor Dietary Intake

Few foods naturally contain vitamin D. Diets lacking fortified foods, dairy products or fatty fish may contribute to deficiency.

Medical Conditions

Certain medical conditions such as kidney disease, liver disease or digestive disorders can affect vitamin D absorption and metabolism.

How Is Vitamin D Deficiency Diagnosed?

Vitamin D deficiency is diagnosed through a simple blood test that measures the level of 25-hydroxyvitamin D in the bloodstream.

Doctors may recommend testing for individuals who experience symptoms of deficiency or belong to high-risk groups.

Early diagnosis allows healthcare providers to recommend appropriate treatment and lifestyle adjustments.

How to Improve Vitamin D Levels

Sunlight Exposure

Regular sunlight exposure is one of the most effective ways to increase vitamin D levels. Experts generally recommend 10 to 30 minutes of sunlight exposure several times per week, depending on skin type and location.

Dietary Sources of Vitamin D

Although limited, certain foods contain vitamin D, including:

fatty fish such as salmon and mackerel
egg yolks
fortified milk and cereals
mushrooms

Including these foods in the diet can help maintain healthy vitamin D levels.

Vitamin D Supplements

In cases of significant deficiency, doctors may recommend vitamin D supplements. The dosage depends on the individual’s vitamin levels, age and health status.

It is important to take supplements under medical supervision to avoid excessive intake.

Preventing Vitamin D Deficiency

Maintaining adequate vitamin D levels requires a balanced combination of sunlight exposure, proper nutrition and regular health monitoring.

Routine health checkups and vitamin testing can help identify deficiencies early and prevent complications.

Adopting a healthy lifestyle with balanced nutrition and outdoor activity can significantly improve vitamin D status and overall health.

Conclusion

Vitamin D deficiency is a common but often overlooked health concern. Symptoms such as fatigue, bone pain, muscle weakness and frequent infections may indicate low vitamin D levels.

Early detection and proper management are essential to prevent long-term health complications. By ensuring adequate sunlight exposure, maintaining a balanced diet and undergoing regular health checkups, individuals can support healthy vitamin D levels and improve overall wellbeing.

Recognizing the warning signs of vitamin D deficiency and seeking timely medical advice can help protect long-term health and maintain optimal body function.

References

  • Indian Council of Medical Research (ICMR) – Nutritional Deficiency Reports

  • World Health Organization (WHO) – Micronutrient Deficiency Guidelines

  • National Institute of Nutrition (NIN) India – Vitamin D Research Reports

  • Lancet Public Health – Nutritional Health Studies

  • National Institutes of Health (NIH) – Vitamin D Fact Sheets for Health Professionals

See all

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