‼️A common source of debate, misconception and confusion is "𝘤𝘢𝘯 𝘮𝘺 𝘤𝘩𝘪𝘭𝘥 𝘣𝘦 𝘷𝘢𝘤𝘤𝘪𝘯𝘢𝘵𝘦𝘥 𝘪𝘧 𝘩𝘦/𝘴𝘩𝘦 𝘩𝘢𝘴 𝘢𝘯 𝘦𝘨𝘨 𝘢𝘭𝘭𝘦𝘳𝘨𝘺?".
Especially now with the circulating Pfizer and AstraZeneca (Oxford) COVID19 vaccines, many have asked me about their safety.
But let's start with the basics.
❓𝐒𝐨 𝐰𝐡𝐲 𝐢𝐬 𝐢𝐭 𝐭𝐡𝐚𝐭 𝐦𝐨𝐬𝐭 𝐨𝐟 𝐭𝐡𝐞𝐦 𝐮𝐬𝐞 𝐡𝐞𝐧𝐬' 𝐞𝐠𝐠𝐬?
🦠The process of growing a virus in an egg leads to that virus becoming less infectious to the human being, but still leading to a protective effect against potential infections in the future.
After a virus is injected, the egg will be sealed with gelatine. This is normally made from pork protein.
🥚On the process of collecting the grown virus from the egg, a small amount of protein will come along as well. This can potentially lead to an allergic reaction.
▶️Studies have shown that this vaccine may contain from no amount to 1ng per 0.5ml of egg protein.
▶️Food challenges done on egg-allergic patients showed most people would react to amounts of 50-100mg, with some as low as 2mg of egg protein.
▶️This means the amount on the vaccine is too small to cause an allergic reaction.
⚠️Saying this, other components might lead to allergic reactions.
The ones I am referring to are 𝐆𝐞𝐥𝐚𝐭𝐢𝐧𝐞 (𝐩𝐨𝐫𝐤 𝐨𝐫𝐢𝐠𝐢𝐧) and 𝐍𝐞𝐨𝐦𝐲𝐜𝐢𝐧.
Both have higher concentrations than Ovalbumin.
➡️𝘛𝘩𝘦 𝘚NIFFLE 𝘴𝘵𝘶𝘥𝘪𝘦𝘴 have shown the safety of the Nasal Flu vaccine.
Several studies have shown that the LAIV (Live Attenuated Influenza Vaccine) that contain less than 0.12μg/mL (so 0.06 μg for a 0.5 mL dose) is safe for patients with an egg allergy.
To produce this vaccine, the virus is grown on chick embryonic fibroblast cells.
In case a patient with an egg allergy needs this vaccine, there two other options that can be used, as they do not contain egg:
1️⃣Human Diploid Cell Vaccine (HDCV)
2️⃣Purified Vero Cell Rabies Vaccine (PVRV)
✅𝐘𝐞𝐥𝐥𝐨𝐰 𝐟𝐞𝐯𝐞𝐫 𝐯𝐚𝐜𝐜𝐢𝐧𝐞
The virus for this vaccine is also grown on chick embryos.
If a patient needs this vaccine, there is only one potential option.
What I am referring to is a graded vaccination programme done in a hospital.
As with the MMR vaccine, the Yellow Fever and the Rabies vaccines one also contain Gelatine.
So extra caution needs to be had in this case.
✅Finally, the COVID19 vaccines:
1️⃣"There is no egg or egg-related component of the Pfizer RNA vaccines.
2️⃣ The Oxford AstraZeneca vaccine is produced in genetically modified human embryonic kidney (HEK) 293 cells.
This means both vaccines are safe to be used in egg-allergic children.
The only children who need to be vaccinated in a hospital are those with an allergy to eggs, with previous anaphylaxis to egg or who had a cardiorespiratory reaction needing admission to Intensive Care or those with coexisting active, chronic asthma.
⛔How many times have you had nasal symptoms, and you have gone to an allergist, but no allergy has been found?
Have you ever felt a sore throat, runny nose or nasal congestion, occasionally itchy eyes, and sometimes problems with your ears?
The summer season is over, and the pollen count is now too low even to count!
So it can no longer be associated with hay or hayfever, so what is it?
If this has happened to you, then it is likely we are talking of a different diagnosis.
𝐍𝐨𝐧-𝐚𝐥𝐥𝐞𝐫𝐠𝐢𝐜 𝐫𝐡𝐢𝐧𝐢𝐭𝐢𝐬 is often also known as noninfectious, perennial eosinophilic rhinitis and non-allergic rhinitis with eosinophilic syndrome.
Many conditions can cause it.
❄As we have reached the cold season, it will be common to see children (not as often in adults) with nasal congestion when exposed to cold air.
❎Some medication can also lead to nasal symptoms.
▶️Among others, Aspirin can lead to rhinitis and be associated with non-atopic Asthma and the development of nasal polyps. Though it is more often seen in adults than in children.
▶️Adults who often use nasal decongestants should also be careful as one of the common side effects is a rebound nasal congestion, called rhinitis medicamentosa. As with Aspirin, this is more common in adults and rarely seen in children.
❗Treatment wise, and apart from antihistamines, it should be the same as with Allergic Rhinitis.
👃The best and first-line treatment are nasal steroids.
❓And which ones to use?
➡️Age 3 years and above - Mometasone furoate (Nasonex) - my choice
➡️Age 6 years and above - Fluticasone furoate (Avamys)
➡️Age 12 years and above - Fluticasone and Azelastine (a combination of steroid and antihistamine - Dymista)
👁For your eyes, there are a couple of choices:
➡️Any age - Sodium cromoglicate (a mast cell stabilizer)- my choice
➡️Age 3 years and above - Olopatadine (a combination of mast cell stabilizer and antihistamines)
➡️Some patients like to use artificial tears as the main choice - though better for allergic rhinitis.
⚠️It is crucial first to achieve a diagnosis, so appropriate treatment can be done, as other therapies might be needed, including treatment of the primary cause.
✅For this condition, it is essential good cooperation between an Allergy Doctor and an ENT specialist.
What is also extremely important is to use the right technique for any nasal spray.
Also, remember to cross your hands.
Right hand to the left nostril.
Left hand to your right nostril.
⚠️Many people think that pet allergies are caused by a 🐕dog's or 🐈cat's fur (or any other pet, for what it matters), but the real source of pet allergies is often a protein that's in the saliva and urine of dogs and cats, also some produced in sebaceous glands. This protein sticks to the dead, dried flakes (dander) from your pet's skin.
❗Some cats or dogs may shed less dander than others, which potentially can lead to fewer symptoms.
👨💻The most interesting piece of research done so far came to the following conclusion:
▶️"There was no evidence for differential shedding of allergen by dogs grouped as hypoallergenic. Clinicians should advise patients that they cannot rely on breeds deemed to be "hypoallergenic" to, in fact, disperse less allergen in their environment."
(Dog allergen levels in homes with hypoallergenic compared with non-hypoallergenic dogs. Am J Rhinol Allergy. 2011 Jul-Aug;25(4):252-6. doi: 10.2500/ajra.2011.25.3606.)◀️.
🐰There is also extensive research done by Prof A. Custovic, related to the development of allergies to pets (can provide references if asked).
🔶️The most common symptoms seen in pet allergy are very similar to most other airborne allergens.
But they will vary depending on the person's own sensitivity to the pet in question.
❗The greater the skin prick test and/or specific IgE, the higher the chance to develop more severe symptoms.
➡️Sneezing or a runny or stuffy nose.
➡️Facial pain (from nasal congestion).
➡️Coughing, chest tightness, shortness of breath, and wheezing.
➡️Watery, red or itchy eyes.
➡️Skin rash or hives.
➡️Anaphylaxis - can happen, though it is extremely rare. There are one or two cases published, by the famous American Mayo Clinic, of dog anaphylaxis. More reports are to cat and 🐎horse.
The worse respiratory symptoms tend to be associated with someone who already has an underlying breathing pathology, like asthma, poorly controlled allergic rhinitis or recurrent wheeze of varied aetiology.
This potentially can lead to significant deterioration, often leading to hospital admission for treatment, often including moderate to intensive admissions and treatment.
Prof John Warner, one of the best known worldwide experts in Allergy, has once said that "If you remove a cat from home, you clean all the walls down, do the laundry, do the draperies, it still takes six months for the level of cat protein to get down to normal."
More of less the same will apply to dogs.
Research done by Allergist Dana Wallace, MD, has shown cat dander to be the smallest among pets. This means it will remain airborne for at least 30mins after being disturbed, leading to constant exposure to it.
What to do?
Depending on the severity of symptoms, you might need to avoid the pet (leading to allergic symptoms) completely.
If mild, then you can try mild avoidance and cleaning methods, like:
➡️Keep the dog out of your bedroom and restrict it to only a few rooms. Be advised that keeping the dog in only one room will not limit the allergens to that room.
➡️Don't pet, hug or kiss the dog; if you do, wash your hands with soap and water.
➡️High-efficiency particulate air (HEPA) cleaners run continuously in a bedroom or living room can reduce allergen levels over time.
➡️Regular use of a high-efficiency vacuum cleaner or a central vacuum can reduce allergen levels.
➡️Wash soft furnishings like duvet covers, curtains, cushions, soft toys on a hot wash cycle.
➡️Bathing your dog at least once a week can reduce airborne dog allergen.
➡️For horse allergy, remove all clothing, bag it, take a shower, before getting in contact with the person allergic to horses.
➡️Nasal symptoms are often treated with steroid nasal sprays, oral antihistamines or other oral medications.
➡️Eye symptoms are often treated with antihistamine eye drops.
➡️Respiratory or asthma symptoms can be treated with inhaled corticosteroids or bronchodilators to prevent or relieve respiratory symptoms.
How many of you have complained that you feel your lips or mouth tingling after eating some fruits or vegetables?
🤧If you also suffer from Hayfever, we are talking about Oral Allergy Syndrome, also known as Pollen Food Syndrome.
⚠️𝗪𝐡𝐚𝐭 𝐢𝐬 𝐢𝐭 𝐭𝐡𝐞𝐧?
This is an allergic reaction, with swelling and itchiness, affecting the mouth, 👄lips, 👅tongue, and throat only.
🔶️Usually, the symptoms are seen within a few minutes of eating certain fruits and vegetables, mainly when they are raw.
It is not common to cause swelling of the throat.
Even less common to cause anaphylaxis.
⚠️𝗪𝐡𝐲 𝐝𝐨𝐞𝐬 𝐭𝐡𝐢𝐬 𝐡𝐚𝐩𝐩𝐞𝐧?
Some proteins in foods are similar to some of the proteins found in certain pollens, so a cross-reaction might occur. That is also why it is called Pollen Food Syndrome.
⚠️𝗪𝐡𝐞𝐧 𝐜𝐚𝐧 𝐬𝐲𝐦𝐩𝐭𝐨𝐦𝐬 𝐬𝐭𝐚𝐫𝐭?
🧒For a child to suffer from hayfever, they usually need to be exposed to 2 pollen seasons.
For Oral Allergy Syndrome to develop, they need to be exposed to the food causing the reaction, many times.
This means it is not common to find it in toddlers.
⚠️𝐒𝐨 𝐢𝐭 𝐦𝐚𝐢𝐧𝐥𝐲 𝐚𝐟𝐟𝐞𝐜𝐭𝐬:
This type of symptoms are not associated only with the pollen season, this as we can find those foods available throughout the year.
Saying this, symptoms usually are higher when the pollen count is also higher.
⚠️𝗪𝐡𝐚𝐭 𝐚𝐫𝐞 𝐭𝐡𝐞 𝐦𝐨𝐬𝐭 𝐜𝐨𝐦𝐦𝐨𝐧 𝐩𝐨𝐥𝐥𝐞𝐧𝐬 𝐰𝐞 𝐧𝐞𝐞𝐝 𝐭𝐨 𝐥𝐨𝐨𝐤 𝐟𝐨𝐫, 𝐭𝐨 𝐬𝐚𝐲 𝐭𝐡𝐞𝐫𝐞 𝐢𝐬 𝐚 𝐜𝐨𝐧𝐧𝐞𝐜𝐭𝐢𝐨𝐧?
🔷️𝘎𝘳𝘢𝘴𝘴𝘦𝘴 (𝘢𝘴𝘴𝘰𝘤𝘪𝘢𝘵𝘪𝘰𝘯 𝘪𝘴 𝘥𝘰𝘶𝘣𝘵𝘧𝘶𝘭)
➡️Ragweed (association still unclear)
➡️Parietaria species (a member of the Urticaceae family - nettles among others)
⚠️𝗪𝐡𝐚𝐭 𝐜𝐚𝐧 𝐰𝐞 𝐝𝐨 𝐚𝐛𝐨𝐮𝐭 𝐢𝐭?
We usually suggest that parents or patients cook the fruits or vegetables that might be causing the symptoms.
➡️This is because the protein involved in this reaction is not stable to high heat, thus changing its form leading to the absence of reactions in most patients.
⚠️Caution as in the case of roasted hazelnuts and cooked celeriac, in some cases, minute amounts of the protein might still cause symptoms in highly sensitized patients.
✅There is also the possibility that immunotherapy directed at the pollen involved in the cross-reaction, might lead to a decrease of symptoms.
🔶️After having a diagnosis made (and this is one of the reasons component diagnostics are needed), a dietitian's cooperation is required, so appropriate follow-up and plan to introduce other foods that are closely related to the one initially the patient reacted to.
If your child has a reaction, the best course of action is:
- give antihistamines
- call 999 if worried
- avoid food(s) thought to be causing symptoms
- ask GP to refer to a Consultant Paediatric Allergist
The incidence of peanut allergy has been increasing significantly in developed countries.
Many reasons have been found for such growth, but so far no proper treatment has been found to deal with it.
Often, antihistamines are the first choice when there is an allergic reaction, with the occasional need to use adrenaline as well.
Most of the symptoms start in childhood and persists throughout life.
Due to this, the search for ways to deal with this specific allergy is ongoing, though not matching current needs.
As such, today, I will focus on a promising medication that might lead to a significant change in the way we deal with peanut, and possibly nut, allergy.
⚠️On a Phase 2a randomized placebo control trial, running for six weeks, a single injection of Etokimab showed that it could desensitize peanut allergic adults.
➡️Food challenges, skin prick tests and blood tests were done at day 15 and 45, after injection
➡️73% (first challenge) and 57% (second challenge) passed a food challenge with 275mg of peanut protein (versus 0% in the control group)
➡️Several immune mediators were also reduced
❗They concluded that it could potentially desensitize peanut-allergic participants and possibly reduce atopy-related adverse events.
❓I understand the first part, but what is the connection to atopy?
Let me explain.
🔸️IL33 belongs to a group of proteins (cytokines) important in cell signalling (basically part of the immune cascade).
🔸️It also belongs to a small group called alarmins, which are biomolecules that can initiate and maintain a non-infectious inflammatory response (like in allergies).
🔸️It is also known to be released or elevated when there is skin damage, like in atopic dermatitis or eczema (independently of its origin).
▶️Can you see me coming again to the top priority of maintaining the skin barrier to prevent allergy?◀️
⚠️My opinion about it:
How does it compare to the current two available oral peanut immunotherapy?
CA002 (Cambridge) and AR101 (London)
🔹️Both use an “up-dosing” programme to achieve a specific tolerable dose (1600mg for the former and 600mg for the latter).
🔹️AR101 had limitations, like participants being selected based on sensitivity to a maximum of 100 mg of peanut protein.
🔹️This does not represent the entire population with peanut allergies, half of whom have reactions to doses >100 mg.
⚠️Michael R. Perkin, Consultant Paediatric Allergist PhD, wrote that the major concern regarding this immunotherapy is that 𝐚𝐥𝐥𝐞𝐫𝐠𝐞𝐧 𝐭𝐨𝐥𝐞𝐫𝐚𝐧𝐜𝐞 𝐭𝐡𝐚𝐭 𝐢𝐬 𝐢𝐧𝐝𝐮𝐜𝐞𝐝 𝐰𝐢𝐥𝐥 𝐛𝐞 𝐭𝐞𝐦𝐩𝐨𝐫𝐚𝐫𝐲, 𝐚𝐧𝐝 𝐥𝐨𝐬𝐭 𝐢𝐟 𝐫𝐞𝐠𝐮𝐥𝐚𝐫 𝐜𝐨𝐧𝐬𝐮𝐦𝐩𝐭𝐢𝐨𝐧 𝐜𝐞𝐚𝐬𝐞𝐬.
▶️Neither groups have attempted to establish the duration for which allergen tolerance is maintained in the absence of ongoing consumption, potentially lifelong, 𝐫𝐞𝐠𝐮𝐥𝐚𝐫 𝐜𝐨𝐧𝐬𝐮𝐦𝐩𝐭𝐢𝐨𝐧 𝐦𝐚𝐲 𝐛𝐞 𝐧𝐞𝐞𝐝𝐞𝐝 𝐭𝐨 𝐦𝐚𝐢𝐧𝐭𝐚𝐢𝐧 𝐚𝐥𝐥𝐞𝐫𝐠𝐞𝐧 𝐭𝐨𝐥𝐞𝐫𝐚𝐧𝐜𝐞.
𝐓𝐡𝐢𝐬 𝐦𝐞𝐚𝐧𝐬 𝐩𝐚𝐭𝐢𝐞𝐧𝐭𝐬 𝐰𝐨𝐮𝐥𝐝 𝐧𝐞𝐞𝐝 𝐭𝐨 𝐭𝐚𝐤𝐞 𝐭𝐡𝐞 𝐦𝐞𝐝𝐢𝐜𝐚𝐭𝐢𝐨𝐧 𝐨𝐧 𝐚 𝐝𝐚𝐢𝐥𝐲 𝐛𝐚𝐬𝐢𝐬 𝐨𝐫 𝐭𝐡𝐞𝐫𝐞 𝐰𝐢𝐥𝐥 𝐛𝐞 𝐫𝐞𝐯𝐞𝐫𝐬𝐚𝐥 𝐨𝐟 𝐬𝐲𝐦𝐩𝐭𝐨𝐦𝐬. 𝐀𝐧𝐝 𝐭𝐡𝐢𝐬 𝐰𝐚𝐬 𝐚𝐥𝐫𝐞𝐚𝐝𝐲 𝐩𝐫𝐨𝐯𝐞𝐧 𝐢𝐧 𝐚 𝐫𝐞𝐜𝐞𝐧𝐭 𝐬𝐭𝐮𝐝𝐲.
➡️To consider that AR101 will cost between $5000 to $10,000 for the first six months of use, and $300 to $400 per month after that.
🌞As the weather warms up, starts raining less and flowers start blooming, my clinic begins getting filled with (as Prof Warner likes to call them) itchy, sneezy, wheezy patients.
💐And this because they suffer with Allergic rhinitis, which is an inflammation of the nasal mucosa caused by an airborne allergen.
These can be either tree pollen or grass pollen.
The name Allergic Rhinitis wasn't used until the 20th Century.
Initially it was called "Summer Catarrh" as described by Dr Bostock, when an association was made with the hay season.
Due to that is was then commonly called "Hayfever", with the name persisting up to now.
The name "Allergic Rhinitis" is the true name of this pathology.
Allergic due to the reaction being made by allergens.
Rhinitis is due to the combination of two Greek words:
The main cause, aroud Spring and Summer, is Pollen.
Being it from Trees or from Grasses.
But Allergic Rhinits can also be due to other airborne allergens. Such as:
⚠️On its own, it is not life threatening.
⚠️The main problem is when associated with poorly or uncontrolled asthma.
⚠️Can also be troublesome for sufferers of Pollen Food Syndrome/Oral Allergy Syndrome.
The most common symptoms are:
🔶️Itching: Nose, eyes, ears, palate
🔶️Loss of smell
🔶️Runny and/or red eyes
✅Skin prick tests are the main source for diagnosis.
💉Blood tests can eventually be done, mainly in primary care.
❓What to do:
𝘚𝘰𝘰𝘯 𝘐'𝘭𝘭 𝘮𝘢𝘬𝘦 𝘢 𝘱𝘰𝘴𝘵 𝘰𝘯 𝘗𝘰𝘭𝘭𝘦𝘯 𝘍𝘰𝘰𝘥 𝘚𝘺𝘯𝘥𝘳𝘰𝘮𝘦 𝘢𝘯𝘥 𝘦𝘹𝘱𝘭𝘢𝘪𝘯 𝘴𝘺𝘮𝘱𝘵𝘰𝘮𝘴, 𝘪𝘯𝘷𝘦𝘴𝘵𝘪𝘨𝘢𝘵𝘪𝘰𝘯 𝘢𝘯𝘥 𝘵𝘳𝘦𝘢𝘵𝘮𝘦𝘯𝘵.
𝘒𝘦𝘦𝘱 𝘺𝘰𝘶𝘳 𝘦𝘺𝘦𝘴 𝘱𝘦𝘦𝘭𝘦𝘥!
"The importance of feeding is part of human life from the day we are born.
"For the first few months, babies are only able to taste sweet and sour, leading to their first choice favouring the sweet taste of mother’s milk. Eventually, at around 6 months, the taste buds develop further. The baby’s palate becomes more sensitive not only to tastes but also to textures."
Read the full blog post on My Allergy Kitchen.
Dr Costa is a Consultant Paediatrician and fellow of the Royal College of Paediatrics and Child Health.