Immunisations and vaccinations If you are planning to travel to a part of the world where it is recommended that you should receive vaccinations for diseases not common in the UK, having HIV means you’ll need to make sure you are being given the right vaccine. It’s therefore important that wherever you go for your vaccines, they know that you are HIV positive so they can give you the correct ones. Types of vaccineThere are three types of vaccine: live attenuated vaccines, inactivated vaccines and sub-unit vaccines. Live attenuated vaccines are usually created from the actual virus or bacteria (known as the pathogen) which causes the illness that you are being vaccinated against. The pathogen in the vaccine is a weakened, or attenuated, form of the pathogen, but not a killed version. Inactivated vaccines are vaccines containing killed versions of the pathogen which causes the illness that you are being vaccinated against. As the killed pathogen is dead, it cannot make you ill. However, with inactivated vaccines the immune system can still recognise the pathogen and develop immunity to it even though it is dead. Sub-unit vaccines are vaccines containing only a fragment of the pathogen which causes the illness that you are being vaccinated against. As it is only a fragment of the pathogen, it cannot make you ill. However with sub-unit vaccines, the fragment of the pathogen is enough for the immune system to recognise and develop immunity against. Inactivated vaccines and sub-unit vaccines are all safe for people with HIV. Some of the live attenuated vaccines are also safe, but others are not recommended for people with HIV, especially if you have a low CD4 count. This is because with a weakened immune system, even though the pathogen has been weakened, the immune system may not be strong enough to prevent an actual outbreak of the disease you were trying to vaccinate against. The following live attenuated vaccines are considered safe for people with HIV, apart from those with a severely weakened immune system: Measles Mumps Rubella (German measles) Polio (given on a sugar cube) The following live attenuated vaccines are considered not safe for people with HIV: BCG (for TB)Typhoid (oral, although there is an inactivated vaccine for typhoid given by injection which is safe)Yellow fever (although it may be ok to be given this if your CD4 count is high)Some countries in South America and Africa require visitors to carry a vaccination certificate as proof they have been vaccinated against yellow fever. If your HIV doctor doesn’t think that your CD4 count is high enough for the yellow fever vaccination, he or she can issue you with a certificate saying you are exempt from yellow fever vaccination. This waiver may not be accepted by all countries, however, and the certificate may also carry information about your HIV status, so it’s worth finding out where you stand with each country you are planning to visit before you book your trip. Vaccinations and viral loadAs all vaccines stimulate your immune system, including your CD4 cells, vaccinations can cause your viral load to rise for a few weeks. Be aware that this may affect your viral load test results in the few weeks following vaccinations, but this would normally be nothing to worry about and your viral load will eventually fall back to what it was within about six weeks. MalariaIf you are travelling to a part of the world where malaria is present, it’s vital that you take the appropriate anti-malaria medication for the part of the world you are travelling to. Anti-malaria medication should not interfere with anti-HIV drugs, so standard anti-malaria medication should be ok for you to take whether you are on HIV treatment or not. Speak to your doctor well in advance of your trip and tell him or her where in the world you are planning to visit. In some areas of the world, the malaria parasite is resistant to some of the anti-malaria medication available, and so your doctor will want to make sure you take the type that are suitable for the region you are travelling to. Be aware that some anti-malaria medication can have unpleasant side effects which could affect your adherence to your anti-HIV drugs. Talk through this with your doctor before you travel so that you will be aware of the possible effects before you go.