Historical review of studies on the effect of treating latent tuberculosis.

Tuberculosis Preventive Therapy (TPT) is widely used in particular among high-risk populations such as close contacts and immunosuppressed people mostly in high-income settings. TPT is widely recommended for high-risk populations including HIV-infected and household contacts globally, but is not widely used. Historical trials on risk groups as well as the general population have documented a marked effect on reductions in incidence of active disease among those treated, as well as on prevalence of latent TB infection (LTBI) in populations where massive roll-out of TPT has previously taken place. This review summarizes the results of large historical trials conducted more than 50 years ago among Inuit and African populations as well as risk groups in the USA and Europe exhibiting similarities with current high-burden populations with current limited use of TPT. The trials demonstrated a 27-95% reduction in incidence of active TB among those receiving preventive treatment compared with placebo, with efficacy depending somewhat on length of treatment but mostly on adherence rates. It was possible to achieve satisfactory adherence rates in most of the trial populations and liver toxicity rates were generally low. The historical trials on preventive treatment for LTBI have documented that large-scale TPT is possible and effective even in high-burden populations in high-incidence areas and is therefore a relevant tool to consider in striving to eliminate the TB epidemic.

Human Immunodeficiency Virus and Hepatitis C Virus Infection Testing Among Commercially Insured Persons Who Inject Drugs, United States, 2010-2017.

BACKGROUND: We assessed prevalence of testing for human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infection among persons who inject drugs (PWID). METHODS: Using a nationwide health insurance database for claims paid during 2010-2017, we identified PWID by using codes from the International Classification of Diseases, Current Procedural Terminology, and National Drug Codes directory. We then estimated the percentage of PWIDs tested for HIV or HCV within 1 year of an index encounter, and we used multivariate logistic regression models to assess demographic and clinical factors associated with testing. RESULTS: Of 844 242 PWIDs, 71 938 (8.5%) were tested for HIV and 65 188 (7.7%) were tested for HCV infections. Missed opportunities were independently associated with being male (odds ratios [ORs]: HIV, 0.50 [95% confidence interval {CI}, 0.49-0.50], P < .001; HCV, 0.66 [95% CI, 0.65-0.72], P < .001), rural residence (ORs: HIV, 0.67 [95% CI, 0.65-0.69], P < .001; HCV, 0.75 [95% CI, 0.73-0.77], P < .001), and receiving services for skin infections or endocarditis (adjusted ORs: HIV, 0.91 [95% CI, 0.87-0.95], P < .001; HCV, 0.90 [95% CI, 0.86-0.95], P < .001). CONCLUSIONS: Approximately 90% of presumed PWIDs missed opportunities for HIV or HCV testing, especially male rural residents with claims for skin infections or endocarditis, commonly associated with injection drug use.

Clinical and Epidemiologic Patterns of Chikungunya Virus Infection and Coincident Arboviral Disease in a School Cohort in Haiti, 2014-2015.

BACKGROUND: Beginning in December 2013, an epidemic of chikungunya virus (CHIKV) infection spread across the Caribbean and into virtually all countries in the Western hemisphere, with >2.4 million cases reported through the end of 2017. METHODS: We monitored a cohort of school children in rural Haiti from May 2014, through February 2015, for occurrence of acute undifferentiated febrile illness, with clinical and laboratory data available for 252 illness episodes. RESULTS: Our findings document passage of the major CHIKV epidemic between May and July 2014, with 82 laboratory-confirmed cases. Subsequent peaks of febrile illness were found to incorporate smaller outbreaks of dengue virus serotypes 1 and 4 and Zika virus, with identification of additional infections with Mayaro virus, enterovirus D68, and coronavirus NL63. CHIKV and dengue virus serotype 1 infections were more common in older children, with a complaint of arthralgia serving as a significant predictor for infection with CHIKV (odds ratio, 16.2; 95% confidence interval, 8.0-34.4; positive predictive value, 66%; negative predictive value, 80%). CONCLUSIONS: Viral/arboviral infections were characterized by a pattern of recurrent outbreaks and case clusters, with the CHIKV epidemic representing just one of several arboviral agents moving through the population. Although clinical presentations of these agents are similar, arthralgias are highly suggestive of CHIKV infection.

Secondary Infections with Ebola Virus in Rural Communities, Liberia and Guinea, 2014-2015.

Persons who died of Ebola virus disease at home in rural communities in Liberia and Guinea resulted in more secondary infections than persons admitted to Ebola treatment units. Intensified monitoring of contacts of persons who died of this disease in the community is an evidence-based approach to reduce virus transmission in rural communities.

Early occurrence of influenza A epidemics coincided with changes in occurrence of other respiratory virus infections.

BACKGROUND: Viral interaction in which outbreaks of influenza and other common respiratory viruses might affect each other has been postulated by several short studies. Regarding longer time periods, influenza epidemics occasionally occur very early in the season, as during the 2009 pandemic. Whether early occurrence of influenza epidemics impacts outbreaks of other common seasonal viruses is not clear. OBJECTIVES: We investigated whether early occurrence of influenza outbreaks coincides with shifts in the occurrence of other common viruses, including both respiratory and non-respiratory viruses. METHODS: We investigated time trends of and the correlation between positive laboratory diagnoses of eight common viruses in the Netherlands over a 10-year time period (2003-2012): influenza viruses types A and B, respiratory syncytial virus (RSV), rhinovirus, coronavirus, norovirus, enterovirus, and rotavirus. We compared trends in viruses between early and late influenza seasons. RESULTS: Between 2003 and 2012, influenza B, RSV, and coronavirus showed shifts in their occurrence when influenza A epidemics occurred earlier than usual (before week 1). Although shifts were not always consistently of the same type, when influenza type A hit early, RSV outbreaks tended to be delayed, coronavirus outbreaks tended to be intensified, and influenza virus type B tended not to occur at all. Occurrence of rhinovirus, norovirus, rotavirus, and enterovirus did not change. CONCLUSION: When influenza A epidemics occured early, timing of the epidemics of several respiratory winter viruses usually occurring close in time to influenza A was affected, while trends in rhinoviruses (occurring in autumn) and trends in enteral viruses were not.

Ancient DNA analysis - An established technique in charting the evolution of tuberculosis and leprosy.

Many tuberculosis and leprosy infections are latent or paucibacillary, suggesting a long time-scale for host and pathogen co-existence. Palaeopathology enables recognition of archaeological cases and PCR detects pathogen ancient DNA (aDNA). Mycobacterium tuberculosis and Mycobacterium leprae cell wall lipids are more stable than aDNA and restrict permeability, thereby possibly aiding long-term persistence of pathogen aDNA. Amplification of aDNA, using specific PCR primers designed for short fragments and linked to fluorescent probes, gives good results, especially when designed to target multi-copy loci. Such studies have confirmed tuberculosis and leprosy, including co-infections. Many tuberculosis cases have non-specific or no visible skeletal pathology, consistent with the natural history of this disease. M. tuberculosis and M. leprae are obligate parasites, closely associated with their human host following recent clonal distribution. Therefore genotyping based on single nucleotide polymorphisms (SNPs) can indicate their origins, spread and phylogeny. Knowledge of extant genetic lineages at particular times in past human populations can be obtained from well-preserved specimens where molecular typing is possible, using deletion analysis, microsatellite analysis and whole genome sequencing. Such studies have identified non-bovine tuberculosis from a Pleistocene bison from 17,500 years BP, human tuberculosis from 9000 years ago and leprosy from over 2000 years ago.

Burden of HIV and hepatitis C co-infection: the changing epidemiology of hepatitis C in HIV-infected patients in France.

BACKGROUND & AIMS: To better evaluate the HIV-HCV co-infection burden in the context of new effective HCV treatment. METHODS: We reviewed all the epidemiological data available on HCV-related disease in HIV-infected patients in France. Sources of data have been selected using the following criteria: (i) prospective cohorts or cross-sectional surveys; (ii) conducted at a national level; (iii) in the HIV-infected population; (iv) able to identify HCV co-infection and chronic active hepatitis C (HCV RNA positive); and (v) conducted during the period 2003-2012. RESULTS: The overall prevalence of HIV-HCV co-infection has decreased from 22-24% to 16-18%. This prevalence decreased from 93% to 87% among injecting drug users while it increased from 4% to 6% among men who have sex with men. The characteristics of patients have changed: decrease in the proportion of patients with chronic active hepatitis C (HCV RNA positive) from 77% to 63% and in the genotypes 2 and 3 HCV infection; increase in the proportion of HCV genotype 1 (from 45-50% to 58%) and genotype 4 (from 15% to 22%). The proportion of patients treated with highly active antiretroviral therapy increased from 76% to 95%, with higher rates of undetectable HIV viral load (47% in 2004 vs. 85% in 2012). CONCLUSION: The decreasing prevalence and the change in patients profile in HIV-HCV co-infection underline the importance of continuing efforts to educate physicians and patients. This should increase the benefit of viral risk reduction policies and increase the access of co-infected patients to HCV treatment.

A brief history of tuberculosis in Iran during the 19th and 20th centuries.

The history of tuberculosis as a worldwide fatal illness traces back to antiquity, a well-known disease in ancient civilizations. However, its causative agent remained unidentified until the last decades of the 19th century, when discovered by Robert Koch. In due course, preparation of the BCG vaccine, application of the Mantoux intradermal diagnostic tuberculosis test and administration of proper antituberculosis medications eventually controlled tuberculosis. However, despite these significant advancements tuberculosis remained uneradicated, particularly in developing countries after the emergence of both multidrug-resistant tuberculosis and HIV co-infection. Presented here, is a brief review of the history of tuberculosis in the world as well as its historical background in Iran, mainly during the 19th and 20th centuries.