BLOOD clots are not uncommon, but there are some telltale signs to look out for including headaches and severe bruising.
Experts last night warned Brits who have had a coronavirus vaccine to seek medical help if they have a headache that lasts for more than four days after initial inoculation.
Read our coronavirus live blog for the latest news & updates…
The MHRA (Medicines & Healthcare products Regulatory Agency) advised that Brits experiencing severe bruising after the jab should also seek help as it could be a sign of a rare blood clot.
Speaking at a Downing Street press conference last night Dr June Raine said said that there has been five reports of cerebral sinus venous thrombosis (CSVT).
She said, they had occurred shortly after vaccination with the AstraZeneca jab.
Dr Raine added: “This type of blood clot can rarely occur naturally in unvaccinated people as well as in people with Covid-19.”
She said: “A causal relationship with the vaccine has not yet been established and that the rate of occurance of these CSVT events among the 11 million vaccinated is extremly rare.”
Dr Raine said that while the MHRA continued to investigate reports of blood clots, as a precautionary measure it would advise “anyone with a headache that lasts more than four days after vaccination or bruising beyond the site of vaccination after a few days to seek medical attention”.
But what are the different types of blood clots and what symptoms do you need to be looking out for?
Cerebral sinus venous thrombosis (CSVT)
CSVT happens when a blood clot forms in the brain’s venous sinuses.
As explained by Dr Raine, this is very rare in both people who have and have not received a vaccine.
The clot prevents blood from draining out of the brain and as a result blood cells can break and leak into the brain tissues – this in turn causes a hemorrhage.
There are a number of risk factors for this kind of clot including cancer, obesity, low blood pressure in the brain and inflammatory bowel disease.
What are the symptoms of CSVT?
Experts say there are a number of symptoms to watch out for when it comes to CSVT and these include:
- Headache
- Fainting
- Blurred vision
- Seizures
- Loss of control of movement
- Comas
Deep vein thrombosis (DVT)
DVT occurs when a blood clot forms in one of the deep veins of your body, usually in your legs.
If a blood clot breaks off from a DVT and travels to the lung, this causes a pulmonary embolism (PE). This can be fatal.
What are the symptoms of DVT?
The symptoms below occur in patients who are suffering from DVT:
- Swelling, usually in one leg (or arm)
- Leg pain or tenderness
- Reddish / blue skin discoloration
- Leg (or arm) warm to touch
Thrombocytopenia
Thrombocytopenia is another type of blood clot which happens when your blood platelet count is so low that the blood is not efficiently clotting when it needs to.
In rare cases, the number of platelets can be so low that dangerous internal bleeding occurs.
What are the symptoms of thrombocytopenia?
- Easy or excessive bruising (purpura)
- Superficial bleeding into the skin that appears as a rash of pinpoint-sized reddish-purple spots (petechiae), usually on the lower legs
- Prolonged bleeding from cuts
- Bleeding from your gums or nose
- Blood in urine or stools
- Unusually heavy menstrual flows
- Fatigue
- Enlarged spleen
BLOOD CLOTS AND VACCINES
Here's everything you need to know when it comes to how blood clots are linked to vaccines
The European Medicines Agency (EMA) said there had been just 30 reports of blood clots among close to five million people given the AstraZeneca vaccine across Europe.
This is far lower than what would be expected, experts say.
Both the EMA and the MHRA have said the vaccine are safe and effective.
For this reason, Brits have been told to carry on taking the vaccine because the benefits of protection against Covid outweighs and potential risk of the jab.
Blood clots – which can cause heart attacks and strokes – are “not uncommon” scientists say, diagnosed about 3,000 times a month in the UK.
About 30 blood clots were reported by 9.7million people given Oxford doses by late February.
In comparison, the figure was 38 cases among the first 10.7million Pfizer vaccines.
AZ has found fewer than 40 cases of blood clots and related conditions in 17 million people vaccinated across Europe.
The drug giant says that the numbers of blood clots “are lower than the number that would have occurred naturally in the unvaccinated population”.
Disseminated intravascular coagulation (DIC)
The European Medicines Agency yesterday said that it had seen seven cases of disseminated intravascular coagulation in 20 million people given the AstraZeneca jab.
The body said that patients had developed this condition alongside low platelets.
DIC is a condition where blood clots form throughout the body – blocking small blood vessels.
What are the symptoms of DIC?
- Leg pain
- Shortness of breath
- Headache
- Problems speaking
- Chest pain
Arterial clot
An arterial clot can block blood and oxygen from reaching your vital organs and this in turn can lead to tissue damage.
Most often they occur in your legs and your feet and can sometimes happen in your brain – in this case they can lead to a stroke.
These types of clots can also take route in your kidneys and intestines.
There have been cases where the clots have happened in the eyes although this is extremely rare.
What are the symptoms of an arterial clot?
- Fingers or hands that feel cool to the touch
- Muscle pains
- Weakness of the affected limb
- Tingling
THE RISKS
Blood clots can occur in people of any age, ethnicity and gender.
But a DVT is more likely to happen if you:
- are over 60
- are overweight
- smoke
- have had DVT before
- take the contraceptive pill or HRT
- have cancer or heart failure
- have varicose veins
Most read in Health News
There are some temporary situations when you’re at more risk of DVT, which is why they can occur in people without the above risk factors.
You could get a blood clot if you:
- are staying in or recently left hospital – especially if you cannot move around much (like after an operation)
- are confined to bed
- go on a long journey (more than 3 hours) by plane, car or train
- are pregnant or if you’ve had a baby in the previous 6 weeks
- are dehydrated
Blood clots can also be a complication of some diseases – including heart disease and diabetes.
Even Covid-19 has been shown to cause blood clots in severely ill patients, often leading to their death.