Causing complications, where?

What are the common side effects of vaccines? What factors can affect vaccine quality and cause complications after vaccination?

Mild side effects

The joy of doctors treating when one of the two children overcame the critical crisis (Photo: VNE) Dr. Tran Tinh Hien - deputy director of Ho Chi Minh City Hospital of Tropical Diseases - said when there was an unfavorable reaction After vaccination occurs, the cause is likely to fall into one of two groups: vaccines or defects in the vaccination process.

Also according to Dr. Tinh Hien, no one product or pharmaceutical product is produced with 100% absolute safety and 100% effective. Trying to produce vaccines with absolute safety is likely to reduce the effectiveness of the vaccine.

Currently with existing technology, vaccine manufacturers try to produce products with the highest safety and efficacy. However, rare adverse reactions have always occurred. Common mild side effects of some vaccines may be local reactions (pain, swelling, redness), fever, irritability, irritability, sometimes diarrhea, headache.

Local reactions usually occur about 1-2 days after vaccination, except for fever and systemic symptoms when vaccinated against measles, or measles - mumps - rubella occurs 5-12 days later.

A vaccine is considered good when there are few side effects and high potency. Local reactions such as soreness, edema or redness at the injection site usually occur about 10% of people vaccinated. Fever also occurs at about 10% or less. Diphtheria vaccine - pertussis - tetanus has a higher rate of side effects, up to 50% of people can be injected.

Errors in vaccination

According to Dr. Tinh Hien, errors in implementing vaccinations can also occur and can cause serious reactions.

Specifically, if the injection is not a sterile technique, such as re-use of pumps, needles; improper pump disinfection, needles; vaccines become infected, abscesses of injection sites, blood infections, poisoning shock, death, viral hepatitis, HIV can occur. If errors in preparation of vaccines: do not shake the vaccine well, use improper phase solution, re-use the phase solution, can make abscesses in place, invalidate vaccines, and die.

With errors when choosing the injection site, such as BCG subcutaneously, DPT is injected too shallow, injected into the buttock, which can cause a reaction or abscess. If the error in shipping: vaccine loses its effect. If you do not respect contraindications, you may experience severe reactions.

Unwanted reactions are usually mild and can be easily treated, leaving no sequelae. A severe reaction occurred at a very low rate (1 / 1,000,000).

Incorrect storage

Pharmacist Do Tuong Phuoc - Scientific director of Vietnam Sanofi Pasteur Company - added: as a rule, conventional vaccines must also be stored at the right temperature of 2-80C. But there are also special types such as polio vaccine that must be stored at -200C. This is a requirement to strictly follow.

If the vaccine missed out of the allowed storage temperature, WHO's recommendation is to bring the vaccine back for quality testing. If it is still effective, use it as soon as possible. If the quality is not guaranteed, it must be canceled properly.

When the vaccine is frozen, a precipitate will form, which may cause swelling and abscess in the injection site. If the vaccine is hotter than the allowed temperature, it may be in a special situation, with the 'live' vaccine instead of the dead virus, it will be warmed up and live again. It can then turn into a virus that is toxic back to the body.

LE THANH HA

Accidents: more than 1 parts per million?

According to GlaxoSmithKline, Priorix ™ vaccines are generally safe and have been used on millions of children around the world.This is true, but here I would like to note that the adverse effects of similar vaccines produced by Merck Company have been reported in literature, and the harmful reaction rate is not lower than 1. Part million cases of vaccination as people comment.

According to an epidemiological study published in 2000, of the 1.8 million people who received the vaccine, 437 reported adverse effects of the vaccine, and of which 137 were considered dangerous. Life caused by vaccines.

Among them, a 13-month-old boy died after being vaccinated for exactly eight days.The cause of death is unknown, but may not be related to the vaccine.The rest are harmful effects such as asthma, seizures, meningitis, pneumonia .

In the above study, in addition to those 'dangerous' cases, there were many minor but mild side effects such as fever (180 cases), rash (132 cases), white blood lymphadenopathy (lymphadenopathy, 69 cases), rhinitis (37 cases) . Most cases of vaccine reaction occur in two times: within 24 hours, or after 7-10 days after injection.

Prof. Nguyen Van Tuan - Garvan Medical Research Institute, Sydney, Australia (ykhoa.net)