Vaccines are weakened or dead bacteria or viruses that we put into the body to stimulate our immune system, thus preventing us from contracting a disease or becoming ill. There’s a bit more to it than that, but essentially when we’re vaccinated, we’re fooling our immune system into believing that the real virus or bacteria is invading our body.

Our immune system fights the disease and because the bacteria or virus is already dead, our immune system usually wins the fight, and in doing so, makes antibodies. These antibodies which remain in our system, sometimes for life, are always ready to fight again, the next time the bacteria or virus invades our body. We become in effect, immune to the disease.

The first vaccine was developed over 200 years ago to fight smallpox and because of its success, smallpox has now been totally eradicated from the world. This is the first and only time that an infectious disease has been eliminated from the planet. There are a few frozen samples that are held in laboratories in the USA and Russia. Following the 9-11 terrorist attack, the US government requested manufacturers to start making the smallpox vaccine again, just in case terrorists were able to access the frozen samples and mass produce the smallpox virus. Today there’s enough vaccine on hand to protect the American people in the event of a smallpox outbreak. There’s also a continuing debate on whether the frozen smallpox samples should be destroyed, eliminating the risk of terrorists accessing them. Scientists, of course, want to keep the samples for further laboratory study.

Thailand follows general standards recommended by the Pediatric Society of Thailand when it comes to vaccinations, and this normally commences at birth with the BCG vaccination being administered for protection against tuberculosis or TB. At birth children also get the Hepatitis B jab, which is repeated after one and six months. The DPT vaccination provides protection against three diseases; diphtheria, pertussis or whooping cough and tetanus. DPT is given in a series of five injections at two, four, six and eighteen months of age and again at four to six years of age. The OPV vaccination commencing at two months protects against polio, which is followed by the MMR vaccine, another mixture of three vaccines to immunize against measles, mumps and rubella. MMR is usually given around one year of age, with a booster between four and six years of age. The JE vaccination for protection against Japanese encephalitis is a series of three shots, the first given at one year of age, the second, one to four weeks later, and the final shot at two to three years of age.

All of the above vaccinations are compulsory in Thailand. There are additional vaccinations that are optional and many doctors would recommend that parents consider including them in the overall vaccination schedule.

These include the Hib vaccine which protects against ‘haemophilus influenza type b’ bacteria. This can cause epiglottitis, a swelling of the throat, and a disease called bacterial meningitis. A new vaccine is the PVC vaccine which protects against pneumococcal infections including pneumonia, septicemia and bacterial meningitis. This vaccine also protects against the Rotavirus which causes severe gastroenteritis. The influenza vaccination is another optional vaccination that parents should consider to protect against this highly contagious respiratory viral illness. The HAV vaccine, for hepatitis A and the VZV vaccine for varicella-zoster virus, one of the eight herpes viruses that cause chickenpox in children and shingles in adults, are also optional. There’s also the controversial HPV vaccination which immunizes females against cervical cancer and genital warts.

Most vaccinations are given whilst we’re children. However even adults should ensure they’re immunized against disease. You should consider yearly influenza shots, as well as ensuring a tetanus booster is given every 10 years. The new HPV vaccinations should be considered for women under 50 years of age, and if you’re elderly then the MMR vaccine is recommended, if you haven’t already had it. The VZV vaccine is also recommended for adults over 60 years.

There’s also some controversy about the safety of vaccines and there are cases where reactions, sometimes severe and leading to death, do occur. Usually reactions are mild such as a slight fever or a sore arm where the injection was given. Court cases in the United States are proceeding in which parents have claimed that childhood vaccinations cause complications such as autism and other neurological disorders, claims that are strongly disputed by experts.

There’s no doubt that vaccines have contributed to eradicating some diseases and they certainly have prevented millions of deaths arising from illness. If you’re unsure of your immunization status, discuss this with your doctor.

Peter Davison is the Manager International Services
at Phuket International Hospital.
Tel: +66 (0)76 249400. Email: info@phuketinternationalhospital.com.