Call / Whatsapp
+918447748545

Published on: Jul 22, 2020
2 minute read
By: Dr Rajan Choudhary

The Oxford Vaccine

Recently we wrote a blog on the success of an RNA vaccine against SARS-CoV-2, the virus responsible for COVID-19. Within just a few weeks of that incredible research breakthrough, researchers at Oxford University’s Jenner Institute have announced a COVID vaccine that has induced remarkable immune response against the virus.

This study was published in the Lancet, one of the most prestigious medical journals in the world, and a simple summary suggests the vaccine has no early safety concern and is able to induce a strong immune response with both T cells and B cell/antibodies.

THE VACCINE

ChAdOx1 nCoV-19, now known as AZD1222, was co-developed by the University of Oxford and one of its spin-off companies, Vaccitech. The vaccine uses a viral vector based on a common cold virus (adenovirus). This carries genetic material for the SARS-CoV-2 spike protein. In our previous blog, we saw how the spike proteins are used by the virus to target and fuse with our target cells, allowing the virus to invade, replicate and ultimately cause the disease known as COVID. It is also a good target for the human immune system to recognize and attack.

The viral vector delivers the genetic material inside our cells. The spike protein is then produced by our cells, recognized by the immune system as a viral target, and an immune response is created against it. This can be antibodies, which recognize, attach to and mark the virus in our blood, allowing for other white blood cells to destroy the virus.

In this case, the vaccine also produced a T cell response. T cells can recognize cells infected by a virus-based on the markers present on the surface of infected cells. They can tell an infected cell to destroy itself, thereby destroying the virus within without spreading the infection. They also have other functions that we will not discuss in this blog.

THE STUDY

This study was a Phase I/II trial that started in April using the vaccine named ChAdOx1 nCoV-19. This vaccine development started in January 2020, and progress on development has been incredibly rapid. Whilst our previous study had just 45 people, this study looked reviewed over 1,000 healthy adults. 10 of these participants received two doses of the vaccine.

In a study the more participants there are, the greater the power of the study. If the vaccine has any side effects, even ones that rarely occur, it is more likely to be picked up in studies with more people. Similarly having more people helps show that the vaccine is effective, and the strong responses are not merely a fluke or accident. Another benefit of this study is it was able to compare the vaccine against a control group. This shows the results were not simply a placebo and allowed comparison of side effects as well.

The majority of side effects were feeling feverish, chills, muscle ache, headache, and malaise, all symptoms treatable with paracetamol. None of the participants had any serious side effects. It took just 14 days to create a T cell response, and 28 days to make strong antibodies. In 91% of patients, this was enough to neutralize the COVID coronavirus. Receiving two doses gave an even stronger antibody response, and all participants were able to stop the virus.

WHAT NEXT

The news from the University of Oxford is needed, as infection rate and mortality continue to increase in countries such as the US and Brazil. The ability to induce an antibody response without causing harm to the patient shows we have made huge progress in the fight against COVID-19. Further Large scale Phase III trials been set up through a global partnership, and include studies in the US with over 30,000 patients, studies in children as well as some in low to middle-income countries.

If successful a vaccine would be essential in preventing a second wave of COVID in the winter when the elderly population is most at risk. And it would be the key to restarting the economy and getting our everyday lives back to where it was pre-pandemic.

Read Blog

Norovirus: Symptoms, Causes, Prevention, and Effective Treatments

Norovirus, often referred to as the “stomach bug,” is one of the leading causes of gastroenteritis worldwide. Known for its rapid spread and uncomfortable symptoms, this virus affects millions of people annually. From understanding its symptoms to learning about norovirus prevention and treatment, this blog delves into all aspects of this highly contagious pathogen.

What is Norovirus?

Norovirus is a group of viruses that cause inflammation in the stomach and intestines, leading to gastroenteritis. This illness, commonly referred to as the “stomach flu,” is unrelated to influenza. Instead, norovirus outbreaks often occur in settings like schools, cruise ships, and nursing homes due to its highly contagious nature.

Symptoms of Norovirus

Symptoms of norovirus typically appear 12 to 48 hours after exposure and can last for 1 to 3 days. Common symptoms include:

Nausea and vomiting: These are hallmark signs of a norovirus infection.
Diarrhea: Often watery, diarrhoea can lead to dehydration if untreated.
Stomach pain: Abdominal cramps are frequent and can range from mild to severe.
Fever and body aches: Low-grade fever and muscle pain are possible.
Fatigue: Dehydration and illness often result in general fatigue.

It is essential to seek medical advice if symptoms persist or worsen, especially in young children, the elderly, or those with weakened immune systems.

How is Norovirus Transmitted?

Norovirus spreads through several pathways, making its transmission difficult to control. Common transmission routes include:

Person-to-person contact: Direct contact with an infected person can easily spread the virus.
Contaminated food or water: Consuming food or beverages handled by an infected individual is a common cause of infection.
Surfaces and objects: Touching contaminated surfaces and touching your mouth or face facilitates the spread.

Norovirus Incubation Period

The norovirus incubation period ranges from 12 to 48 hours after exposure. The virus multiplies in the body during this time, and the individual may start showing symptoms. Despite the incubation period, infected individuals can be contagious before symptoms appear and for several days after recovery.

Causes of Norovirus Outbreaks

Norovirus outbreaks often stem from poor hygiene practices and crowded environments. Common causes include:

Improper handwashing: Neglecting to wash hands after using the bathroom or preparing food.
Contaminated food sources: Seafood, especially shellfish, can harbour norovirus if harvested from polluted waters.
Shared spaces: Enclosed environments like schools, dormitories, and healthcare facilities increase the likelihood of spread.

Norovirus Prevention

Preventing norovirus requires vigilance and proper hygiene practices. Here are effective measures:

Hand hygiene: Wash hands with soap and water for at least 20 seconds, especially after using the restroom or before eating.
Disinfect surfaces: Use a bleach-based cleaner to sanitize surfaces that may be contaminated.
Safe food handling: Wash fruits and vegetables thoroughly and ensure shellfish is cooked properly.
Isolate the infected: Keep infected individuals away from others to prevent further spread.

While no norovirus vaccine is currently available to the public, research is ongoing, and the development of an effective vaccine could significantly reduce the impact of future outbreaks.

Norovirus Treatment

There is no specific antiviral medication for norovirus. Instead, treatment focuses on managing symptoms and preventing complications like dehydration. Effective methods include:

Rehydration: Drink plenty of fluids, including water, oral rehydration solutions, or broths, to replace lost fluids and electrolytes.
Rest: Allow your body to recover by getting adequate rest.
Over-the-counter medications: Anti-diarrheal medications and anti-nausea drugs can alleviate symptoms but should be used under medical supervision.

Norovirus Treatment at Home

Managing norovirus at home involves simple yet effective remedies. These include:

Hydration: Frequent sips of water or oral rehydration solutions.
Light meals: Stick to bland foods like crackers, rice, and bananas to avoid irritating the stomach.
Hygiene practices: Prevent the spread to family members by maintaining strict hygiene and disinfecting shared surfaces.

Why Norovirus is a Global Concern

Norovirus is notorious for causing widespread outbreaks, often affecting hundreds of individuals in a single event. According to the CDC, norovirus is responsible for about 19 to 21 million illnesses annually in the United States alone. Its resilience, coupled with its ease of transmission, makes controlling outbreaks a challenge.

The Role of Norovirus Vaccine Development

Scientists are working to develop a norovirus vaccine, which could be a game-changer in reducing the frequency and severity of outbreaks. While progress is being made, widespread availability remains a future goal.

Conclusion

Norovirus is a formidable adversary, causing discomfort and inconvenience for millions worldwide. Understanding its symptoms, causes, and preventive measures is crucial for minimizing its impact. While there is no cure, proper care and hygiene can help manage symptoms and prevent transmission. Stay informed and prepared to keep norovirus at bay.

If you’re looking for more health tips and insights, consult the experts at Second Medic to ensure you and your loved ones stay healthy and protected.