Is it possible to stop the transmission of hansen’s disease in Brazil?
Prospects and challenges
by Carmelita Ribeiro Filha Coriolano
and Ciro Martins Gomes
Hansen’s disease (HD) is caused by a slow-growing microorganism, Mycobacterium leprae, which is not yet cultivable in artificial environments. Despite its slow development and the need for prolonged contact for transmission, the disease remains endemic in Brazil . Interrupting transmission is a challenge that must be overcome for proper control of the disease and for the reduction of disabilities and suffering that the affected persons face. The success of this interruption depends not only on investments in new diagnostic methods and more effective treatments, but also on the complete improvement of the living conditions and health of the entire Brazilian population. In this article, we will address recent advances and needs regarding diagnostic tests, disease treatment, health education, and social development of the population.
Recently, several advances have been observed in the early diagnosis of HD - which is one of the main pillars in the fight against the disease. Early diagnosis allows prompt initiation of treatment, breaking the transmission chain and preventing the development of disabilities in the affected person . There is no doubt that the development of modern tests is important for a country of continental proportions like Brazil. Tests that aim to detect minimum quantities of genetic material (DNA or RNA) of Mycobacterium leprae are promising. However, their deployment is limited by the need for complex health system structures and the training of skilled workers. It is also worth mentioning that many cases of HD present only clinical manifestations of the disease, and that in these cases no examination is able to detect the infectious agent. These are important challenges to be overcome, especially in more remote areas.
Early treatment, which also depends on early diagnosis, consists of multidrug therapy (polychemotherapy), meaning a set of medications that are administered simultaneously to ensure rapid healing of the disease and break the chain of transmission.  The Brazilian Ministry of Health and the World Health Organization advocate an effective set of free medications for diagnosed patients. For this, the patient must attend the health center every 28 days for 6 or 12 months, depending on the form of HD . At this time, the dose is supervised when the patient takes medication under supervision. The patient should also take daily unsupervised medications, aiming at a complete cure of the disease and to minimize the long-term effects that HD can bring. All these measures, together, ensure that the disease will not be transmitted to people living in the same household.
Health education is also a fundamental part of the fight against HD. This includes the training of professionals at all levels of care, as well as information for the population so that people can recognize the early signs of the disease. All health workers should know the signs and symptoms of HD, with the current focus being the training of primary health workers. In a model of health that guarantees universal care and equity, basic health units are the gateway to early care. Primary care is also responsible for most of the actions of prevention and active search for new patients with HD . Therefore, it is possible to conclude that stimulating academic training in several areas of health is fundamental for the reduction of the disease burden in Brazil. Parallel to the education of health professionals, it is important to invest in the education of the general population. Information about the curative effect of treatment helps in the reduction of stigma and discrimination, besides ensuring adherence to prescribed medications. Health education also directly accelerates the diagnosis of HD. The population, knowing the symptoms of the disease, will access basic health units more quickly if they suspect HD, reducing the chance of transmission.
Finally, success in eliminating HD in Brazil depends on an improvement in all development and social indicators. It is important to remember that previously endemic countries in Asia and Europe eliminated HD as a public health problem even without the advances in complementary tests that we have today . Unfavourable social conditions stimulate several situations that can facilitate the transmission of HD, such as inadequate housing, lack of basic sanitation, malnutrition, and lack of health system coverage.
From the above, it is possible to conclude that the fight against HD transmission requires the development of new diagnostic techniques and treatments, but the elimination of the disease as a public health problem depends on a complex set of actions. Such actions are not restricted to the health care system, but should cover the whole of society. The social and economic developments already achieved, and the new challenges present in our society must be considered in order to combat all neglected diseases, including HD. In conclusion, it is understood that yes, it is possible to stop the transmission of HD in Brazil, but this goal can only be achieved by mobilizing all sectors of society.
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