Health has decided to suspend the vaccination of AstraZeneca in Spain after the notification of several cases of cerebral venous thrombosis that it is necessary to study more in-depth Ministry of Health has decided to suspend vaccination with the AstraZeneca vaccine against Covid-19 in Spain for two weeks. The decision, preventive, is due to the notification of cases of cerebral venous thrombosis, which are very rare in the general population, and that “it is necessary to study more in-depth

The Spanish Agency for Medicines and Health Products (AEMPS) announced this Monday, March 15, that in the last week it had received notification of “several cases of thrombotic events in some European countries including Spain, temporarily related to vaccination against Covid-19 from AstraZeneca.

At first, the health authorities did not consider that there was any possible relationship between these coagulation problems and the administration of the vaccine, since they were not associated with a specific batch, nor was there a disproportion between the number of reported cases between the people vaccinated and the number of cases occurring naturally in the general population.

However, between Saturday, March 13, and Monday, March 15, several cases of a very specific type of thrombotic event were recorded that needs to be studied further since it is very rare in the general population, said the AEMPS. it’s a statement.

On Monday, after an emergency meeting of the Interterritorial Health Council, the Minister of Health assured that the cases identified are out of the common pattern, they are rare. They are very few but significant. Darius wanted to send a message of calm to the population and explained that -at that time- there had only been one case in Spain and he was recovering. But as of this Wednesday, three have already been detected, including that of a teacher who died in Marbella and whose relationship with the vaccine is being investigated.

These are cases of cerebral venous thrombosis (specifically cerebral venous sinus thrombosis) with the particularity, details the AEMPS, that these thromboses are associated with a decrease in the number of platelets in the blood, “which would suggest an abnormal activation of the blood pressure system. the coagulation that would result in this obstruction of the cerebral veins.

According to data from the Spanish Society of Neurology (SEN), cerebral venous sinus thrombosis is a rare cerebrovascular disease (it represents less than 0.5% of the total cases of cerebrovascular diseases that occur in Spain). Its incidence is considered to be around 1-1.3 cases / 100. 000 inhabitants per year.

It can affect any age group, although it is slightly more common in women and young patients. Among the sex-specific risk factors are oral contraceptives, pregnancy, and the use of hormonal therapies All European regulatory agencies work to collect and analyze the available information. According to AEMPS data, approximately 17 million people have received the AstraZeneca vaccine in the EU and the UK, and “the number of reported cases is very low in proportion to the number of people vaccinated.” Specifically, in the European Union, about 6 million doses of the vaccine have been administered and the AEMPS has a notification of 11 cases of cerebral venous sinus thrombosis (there are 30 notifications of thrombosis in total).

Despite the low incidence, this subgroup of cases should be studied to find out if, in addition to having a temporal relationship with the administration of the vaccine, there is a possible causal relationship, said Health. On Tuesday, March 16, two new notifications of suspected adverse reactions were registered in the FEDRA database of the Spanish Pharmacovigilance System coordinated by the AEMPS: A person with an ischemic stroke with the hemorrhagic transformation that, unfortunately, had a fatal outcome and a person with abdominal venous thrombosis. Both had been vaccinated with the AstraZeneca vaccine in the past 16 days. According to what has transpired, the deceased person was a 43-year-old teacher from Marbella who received the vaccine on the 3rd and died on the 16th due to a brain hemorrhage.

In total, three possible cases of adverse effects have been registered among the 975,661 people vaccinated in Spain with AstraZeneca so far. As clarified by Health, the AEMPS, together with the rest of the regulatory agencies and the EMA (European Medicines Agency) are gathering more information and carrying out an exhaustive investigation to find out if, in addition to a temporary relationship with the administration of the vaccine, there is a possible causal relationship.

While it is being investigated, the Ministry of Health considers it prudent to suspend the vaccination with the AstraZeneca vaccine against Covid-19 from this March 16 and for the next two weeks, Health said Monday. As explained by Jordi Nicolas, vice president of the Spanish Society of Hospital Pharmacy (SEFH), what happened is a common procedure within the pharmacovigilance process that shows that the controls work.

The incidence detected is very low reassures the specialist, who recalls that the number of reported cases is similar to that of the general population. In any case, remember, in the event of any suspicion of an adverse event, the indicated thing is to investigate whether there is a possible causal relationship. Determining the cause is fundamental, he stresses.

It is possible that there is no causal relationship between thrombosis and vaccines or that the complication is due to an alternative justification. If there is a relationship, the AEMPS points out, measures that try to minimize the risk to the maximum may also be studied, such as the identification of factors that predispose to the appearance of this type of thrombi.

It is essential to evaluate the benefit-risk balance, says Nicolas. In products such as certain oral contraceptives, in which an association with the appearance of thrombi has been detected, this information is included in the product leaflet and its use in people at risk is discouraged.


After receiving a vaccine against Covid-19, it is common to notice a headache. However, if you have received the vaccine in the last 14 days and the headache is severe and persistent, changes significantly when lying down, or is associated with visual disturbances or other persistent neurological symptoms, it is recommended to consult your doctor, he says. the AEMPS.

According to data from the Spanish Society of Neurology, the headache that generates a cerebral venous sinus thrombosis is very characteristic: it can have a sudden onset, it can be located only on one side of the head it worsens when the patient is lying down or exercising. interrupts the night’s rest and in addition to not responding to the usual treatments for the headache, it progressively worsens.

Also, signs similar to those of stroke may appear (focal deficits, loss of strength or sustained sensitivity, impaired gait or language or speech disturbance, confusional episodes, loss of vision, etc.)

Generally and, especially if it is treated in time, patients suffering from cerebral venous sinus thrombosis have a favorable prognosis. In Spain, recovery after cerebral venous sinus thrombosis is complete in approximately 80% of patients and only 5% develop some type of severe sequelae, according to the SEN.


The vice president of the SEFH, Jordi Nicolás, calls for tranquility to the population and recalls that the incidence of detected thromboses is very low. People who have already received the first dose and have not noticed any problem in the first 3-5 days should have absolute peace of mind, says the specialist.

As he explains, there is evidence that a first dose of the vaccine already confers immunity against Covid-19. Therefore even in the hypothetical case that the second dose could not be administered, a percentage of the population would already have protection against infection he says. In these cases, he indicates, studies can be done to evaluate if these people are immune. If necessary the indication to start another vaccination regimen could also be evaluated.

In principle, with the available data, it does not seem that we are facing a serious security problem, although the possible relationship reported must be analyzed. The analyzes are being carried out in haste. In a few days we will have conclusions, says Nicolas.


Denmark was the first country to activate an alert a few days ago for a group of serious cases of rare thromboembolic phenomena, which had coincided in time with vaccination. These notifications led to the first precautionary suspensions of vaccination. Later, other countries have made the same decision, such as Iceland, Norway, Ireland, Germany, France, Portugal, or Sweden. In other countries, such as Austria, Estonia, Latvia, Lithuania, and Luxembourg, the use of some specific lots has been suspended.

However, other countries, such as the United Kingdom or Australia, have decided to continue with vaccination, in line with the position held by the WHO or the European Medicines Agency itself.

This disparity in criteria can confuse people, explains Federico Martinon-Torres, vaccine specialist and head of the Pediatrics service at the Santiago University Hospital Complex. However, he clarifies, it must be remembered that the decision to suspend the administration of a drug does not only depend on technical or scientific criteria. There are also factors that can influence, such as caution, a sense of protection or the fact that other alternatives are available that allow continuing vaccination.” All these aspects influence the final decision to suspend or not the administration of a drug after the temporal association with certain events. In any case, Martinón-Torres remarks, “we are talking about a very low incidence, so


For now, the WHO continues to recommend standard vaccination, although it continues to evaluate the available data. Also, the European Medicines Agency ( EMA ) is analyzing what happened and is expected to make a definitive statement this Thursday. While the investigation is ongoing, the EMA continues to note that the benefits of the vaccine outweigh its risks.


The AstraZeneca vaccine was developed by modifying an adenovirus to contain genetic information for SARS-CoV-2. It does not contain the complete coronavirus and cannot cause disease.