Prevalence of multidrug-resistant tuberculosis in Latin America and the Caribbean: a systematic review and meta-analysis.

OBJECTIVES: To evaluate the prevalence of multidrug-resistant tuberculosis (MDR-TB) in individuals living in Latin America and the Caribbean (LAC). METHODS: We searched the MEDLINE, Embase and Literatura Latino Americana e do Caribe em Ciências da Saúde (Lilacs) databases until 08 August 2019 for all studies on the subject, without time or language restrictions. Original studies reporting the prevalence of infection with Mycobacterium tuberculosis resistant to isoniazid and rifampicin simultaneously (MDR) in LAC, the prevalence of resistance in cases with no previous treatment (new cases) and the prevalence of resistance in previously treated cases were selected. Considering the expected heterogeneity between studies, all analyses were performed using the random effects model, and heterogeneity was assessed using the I2 statistic. RESULTS: We included 91 studies from 16 countries. The estimated overall prevalence was 13.0% (95% CI 12.0-14.0%), and the heterogeneity between studies was substantial (I2  = 96.1%). In the subgroup analyses, it was observed that the prevalence of MDR-TB among new cases was 7.0% (95% CI 6.0-7.0%) and in previously treated cases was 26.0% (95% CI 24.0-28.0%). CONCLUSIONS: This review highlights multidrug resistance to antituberculosis drugs in LAC, indicating that prevention strategies have not been effective. Government institutions should invest heavily in strategies for early diagnosis and the rapid availability of effective treatments and prioritise adequate protection for health professionals. In addition, screening programmes should be adopted to prevent secondary cases.

OBJECTIFS: Evaluer la prévalence de la tuberculose multirésistante (TB-MDR) chez les personnes vivant en Amérique latine et dans les Caraïbes (ALC). MÉTHODES: Nous avons effectué des recherches dans les bases de données Medline, EMBASE et Literatura Latino Americana e do Caribe em Ciências da Saúde (Lilas) jusqu'au 08 août 2019 pour toutes les études sur le sujet, sans restriction de temps ou de langue. Des études originales faisant état de la prévalence de l'infection à Mycobacterium tuberculosis résistante à l'isoniazide et à la rifampicine simultanément (MDR) dans la région ALC, de la prévalence de la résistance dans les cas sans traitement antérieur (nouveaux cas) et de la prévalence de la résistance dans les cas précédemment traités ont été sélectionnées. Compte tenu de l'hétérogénéité attendue entre les études, toutes les analyses ont été effectuées à l' aide du modèle à effets aléatoires et l'hétérogénéité a été évaluée à l' aide de la statistique I2 . RÉSULTATS: Nous avons inclus 91 études de 16 pays. La prévalence globale était estimée à 13,0% (IC95%: 12,0%-14,0%) et l'hétérogénéité entre les études était importante (I2 = 96,1%). Dans les analyses des sous-groupes, il a été observé que la prévalence de la TB-MDR parmi les nouveaux cas était de 7,0% (IC95%: 6,0%-7,0%) et dans les cas précédemment traités de 26,0% (IC95%: 24,0%-28,0%). CONCLUSIONS: Cette revue met en évidence la multirésistance aux médicaments antituberculeux dans la région ALC, indiquant que les stratégies de prévention n'ont pas été efficaces. Les institutions gouvernementales devraient investir massivement dans les stratégies de diagnostic précoce et la disponibilité rapide de traitements efficaces et accorder la priorité à une protection adéquate pour les professionnels de la santé. De plus, des programmes de dépistage devraient être adoptés pour prévenir les cas secondaires.

Seroprevalence of hepatitis E in adults in Brazil: a systematic review and meta-analysis.

BACKGROUND: Hepatitis E virus (HEV) is a member of the Hepeviridae family; it has four main genotypes and one serotype. While genotypes 1 and 2 cause epidemic hepatitis and are transmitted via water and the fecal-oral route, genotypes 3 and 4 are zoonotic. In the various seroprevalence studies of hepatitis E in Brazil, the numbers reported vary widely and are difficult to interpret. The aim of this study was to analyze existing seroprevalence studies of hepatitis E in adults in Brazil. MAIN TEXT: We searched the PubMed, Latin American and Caribbean Health Sciences and Embase databases for studies published from inception to May 12, 2018 concerning infection by HEV in Brazil without time period or language restrictions. We included studies that presented data concerning hepatitis E seroprevalence in adults in Brazil, had a sample size ≥50 patients and whose method used for the detection of anti-HEV was standardized and commercialized. We also evaluated the quality of the articles using a list of criteria that totalized 9 items. Of the 20 studies ultimately analyzed, 10 (50%) were from the southeast region of Brazil, 3 (15%) were from the central-west region, 3 (15%) were from the northern region, 2 (10%) were from the northeast region and 2 (10%) were from the southern region. Regarding the quality evaluation of the studies, the mean score was 5.6 (range: 4-8). The estimated overall seroprevalence of HEV infection in the adult population was 6.0% (95% CI: 5.0-7.0); in subgroup analyses, we observed that the prevalence of anti-HEV antibodies in blood donors was 7.0% (95% CI: 5.0-8.0), whereas in the general population, it was 3.0% (95% CI: 2.0-4.0). CONCLUSIONS: The results of this systematic review indicate that there should be national investment in the prevention of hepatitis E virus infection in Brazil, including the implementation of improvements in basic sanitation and guidance regarding the appropriate handling of animal waste and the optimal cooking of vegetables, meat and their derivatives.

The best algorithm to confirm the diagnosis of HTLV-1 and HTLV-2 in at-risk individuals from São Paulo, Brazil.

The ability to confirm the diagnosis of human T-lymphotropic virus types 1 and 2 (HTLV-1 and HTLV-2) in at-risk individuals in São Paulo, Brazil by Western blotting (WB), conventional polymerase chain reaction (tax and pol PCR) and real-time PCR (pol) is compared. Seventy-three blood samples that were reactive in HTLV-1/2 serological screening enzyme immunoassays (EIAs) were evaluated. HTLV-1/2 was confirmed in 53 blood samples: 48 were positive by WB, 41 were positive by PCR and 42 scored positive by real-time PCR assays (37 of 48 WB-positive samples plus five WB-indeterminate samples that were further confirmed by sequencing). Although WB was able to detect more cases of HTLV-1/2 infection, the real-time PCR assay was able to discriminate between these two viruses and confirm an individual HTLV-1/HTLV-2 diagnosis in two HTLV WB-untyped samples and five WB-indeterminate samples. Because of the large number of WB-indeterminate samples and the cost of the WB assay in Brazil, it is proposed an algorithm that employs two EIAs for screening and then real-time PCR to confirm the infection, followed by testing any PCR-negative samples with the WB assay. This strategy reduces costs and improves the accuracy of the diagnosis of HTLV-1/2.

Comparison of signal-to-cutoff values in first, second, and third generation enzyme immunoassays for the diagnosis of HTLV-1/2 infection in "at-risk" individuals from São Paulo, Brazil.

Data obtained during routine diagnosis of human T-cell lymphotropic virus type 1 (HTLV-1) and 2 (HTLV-2) in "at-risk" individuals from São Paulo, Brazil using signal-to-cutoff (S/C) values obtained by first, second, and third generation enzyme immunoassay (EIA) kits, were compared. The highest S/C values were obtained with third generation EIA kits, but no correlation was detected between these values and specific antibody reactivity to HTLV-1, HTLV-2, or untyped HTLV (p=0.302). In addition, use of these third generation kits resulted in HTLV-1/2 false-positive samples. In contrast, first and second generation EIA kits showed high specificity, and the second generation EIA kits showed the highest efficiency, despite lower S/C values. Using first and second generation EIA kits, significant differences in specific antibody detection of HTLV-1, relative to HTLV-2 (p=0.019 for first generation and p<0.001 for second generation EIA kits) and relative to untyped HTLV (p=0.025 for first generation EIA kits), were observed. These results were explained by the composition and format of the assays. In addition, using receiver operating characteristics (ROC) analysis, a slight adjustment in cutoff values for third generation EIA kits improved their specificities and should be used when HTLV "at-risk" populations from this geographic area are to be evaluated.