Vall d'Hebron detects that the multiresistant tuberculosis rate in a rural area of Angola is almost four times higher than the one estimated by WHO

Vall d'Hebron University Hospital has led a study that has shown that the rate of tuberculosis multiresistant in the rural area of Cubal (Angola) is four times higher than estimated by the World Health Organization (WHO). Specifically, Vall d'Hebron experts have confirmed that the primary multiresistant tuberculosis rate (that is, patients who suffer from the disease for the first time) is 8% (WHO estimated it at 2.8%). In the case of secondary multiresistant tuberculosis (patients who have already had the disease previously), the rate is 71% (WHO estimated it at 21%). The study was published in the journal Emerging infectious diseases.

As Dr. explains Israel Molina, coordinator of the Vall d'Hebron Department of Tropical Medicine and International Health Service, "This study is part of a collaborative project with the Hospital Nossa Senhora da Paz in Cubal, from Angola, which began in 2008 to offer research, assistance and teaching." Dr. Molina points out that, recently, Vall d'Hebron researchers observed that there was a high failure of tuberculosis treatment among patients who came to this hospital. For this reason, a joint study was started to detect the multiresistant tuberculosis rate for treatments between the Infectious Diseases Service and the Microbiology Service of Vall d'Hebron, with the collaboration of an expert in the Research Support Unit of the ICS Catalunya Central and with the financing of the Probitas Foundation.

The first step was to send a molecular diagnostic device to the Hospital Nossa Senhora da Paz in Cubal to detect the presence of multiresistant tuberculosis among patients. In this way, explains Dr. Ariadna Rando from the Vall d'Hebron Microbiology Service "in Angola, a rapid diagnosis was carried out in less than two hours with only the sputum, and, later, the samples were sent frozen to Vall d'Hebron, where we were responsible for corroborating the diagnosis." To carry out a multiresistency analysis, a highly specialized laboratory with high levels of security is necessary. Two factors that meet the microbiology laboratories at Vall d'Hebron, centre of reference in Spain and supranational tuberculosis reference laboratory of the WHO. The analyses carried out by the Vall d'Hebron experts confirmed the high prevalence of multiresistant tuberculosis among the patients of the Hospital Nossa Senhora da Paz in Cubal. "They are the highest multiresistant tuberculosis rates ever found in the African continent," adds Dr. Molina, who is also a researcher at the Vall d'Hebron Research Institute's Infectious Diseases Group (VHIR).

Changes in the National Tuberculosis Control Program of Angola

This discovery has led to a change in Angola's health policies. Dr. Israel Molina explains that, to date, there has been no study on the presence of multiresistant tuberculosis in that country. "As a result of the results of our research, there have been cases of multiresistant tuberculosis, which has made it possible for the National Tuberculosis Control Program to include second-line drugs, that is, those used to treat multiresistant tuberculosis. This is fundamental not only for the person suffering from the disease, but also to reduce the new infections, "says Dr. Molina. 

The challenge of multiresistant tuberculosis

Tuberculosis is a serious infectious disease caused by mycobacteria that is transmitted through coughing, sneezing, talking or spitting. It usually attacks the lungs but can also affect the central nervous system, the lymphatic system, the circulatory system, the genitourinary system, the gastrointestinal system, bones, joints and even the skin.

The treatment of tuberculosis uses antibiotics to kill the bacteria but it requires long periods of treatment (between six months and one year) to eliminate them completely. Multiresistent tuberculosis is the one that does not respond, at least, to isoniazid or to rifampicin, the two most potent antituberculosis This pathology constitutes a serious problem of  public health  in many developing countries, because it has a worse prognosis and the treatment is even longer, it has more side effects and requires more expensive drugs and will be one of the biggest challenges in public health worldwide in the coming years.