THE Immunology department of the Noguchi Memorial lnstitute for Medical Research (NMIMR), University of Ghana, Legon, will soon embark on a malaria vaccine trial to fight against the malaria parasite. The vaccine, which will be introduced into the blood will help the body to develop immunity to the parasite and this will prevent the disease because the body is ready to fight it. So far apart from the available drugs to the resistance of the parasite there is no vaccine against the malaria parasite. A vaccine is a substance that causes the immune system to develop responses that protect against a specific disease. Dr Ben Gyan, a senior Research Fellow and head of the Immunology department of NMIMR told The Spectator in an interview last Tuesday that serious efforts were being made to get the vaccine. So far the first part of phase one, which involved testing the vaccine outside the country has been completed. The second part of phase one which will be done in Ghana will look more at safety and the vaccine will be tested only on a few adult volunteers. "It is the beginning of a long journey, when phase one is complete we will then move on to find out whether the vaccine is efficacious and safe after which it would be licensed and used as vaccine to prevent malaria", he said. That, he said, would be done alongside other malaria control projects. Dr Gyan said, currently, there are two types of malaria vaccines under development. The ideal malaria vaccine will be the anti-parasite vaccine which will prevent the parasite from getting into the blood stream to cause a disease. The vaccine, he said, would destroy majority of the parasites during the first-five days after a mosquito bite to prevent them from infecting the red blood cells. "However, we are unlikely to achieve complete resistance to malaria infection," he hinted. Dr Gyan further explained that the other type of vaccine which is the anti-disease vaccine, will deal with the clinical phase of the disease in that one may have the parasite infection alright but the vaccine will protect against severe disease and death. "Such a vaccine will have the capacity of limiting the ability of the parasite to successfully infect a large number of red blood cells" he added. Another type of vaccine which is being developed is the transmission-blocking vaccine. This vaccine, Dr Gyan said was designed to protect the entire community rather than the immunized individual. "It works by inducing protective antibodies against the malaria parasite that the mosquito picks during a bite and thereby reducing the intensity of malaria transmission", he explained." As to whether the introduction of a malaria vaccine will completely eliminate the disease, Dr Gyan replied that "this is not feasible because the malaria parasite is genetically complex so that during each time the parasite infection presents thousands of antigens (substances that enter the body and can cause disease) to the human immune system. "The introduction of a malaria vaccine would be integrated into a holistic malaria control programme which include vector control, patient management, good hygiene and good nutrition as well as improved infrastructure," he stated but added that "not all the antigens are relevant or useful for vaccine development." There are several life stages and the parasite changes its form while in the human host for which the immune system needs to cope. Besides that, he included that the parasite had evolved a series of strategies that allow it to confuse the human immune system. Currently, a number of malaria vaccine trials are going on in many parts of the world. In Ghana it is at Kintampo in the Brong Ahafo Region and Agogo in the Ashanti Region. Vaccine trials involve many phases including the safety assessment, immunogenicity (the extent to which an individual responds to the vaccine) and efficacy phases. The development of a drug can take up to 12 years. For about 17 years now the department of immunology through Dr Gyan, Dr Daniel Dodoo, a Senior Research Fellow and Dr Michael Ofori, a Research Fellow, has been working in this area to identify solutions to protect people against malaria, especially severe malaria which include cerebral malaria. Source: The Spectator