Introduction
Tuberculosis (TB) is a treatable infectious disease caused by Mycobacterium tuberculosis bacteria. Other bacteria of this complex, such as M. africanum, M. canetti, M. caprae, M. microti, and M. pinnipedii, can rarely be the cause of TB, too. TB can be asymptomatic, which is also called latent TB. Immune system response usually keeps latent tuberculosis under control, preventing it from activation. People with latent TB are also unable to infect others, as tuberculosis is spread through the air by a cough or sneeze of people with pulmonary TB. Tuberculosis commonly affects the lungs but, in some cases, can affect other organs of the human body. The symptoms usually include chronic cough, fever, and weight loss. The mortality rate has drastically decreased with the help of modern treatment by multiple antibiotics (Glaziou, Floyd, & Raviglione, 2018). However, antibiotic resistance has become a new problem for doctors and scientists, as this eventually led to the new types of TB: multiple drug-resistant tuberculosis and extensively drug-resistant tuberculosis (Glaziou et al., 2018). Although TB is not considered a severe threat to humanity, the elimination of this infection faces many challenges and factors to be considered, depending on certain areas.
Tuberculosis
Epidemiology
Although the mortality rates and the spread of the disease dramatically decreased during the 20th century, tuberculosis is still a significant threat. According to researchers, nowadays, roughly one-quarter of the entire world population is infected with TB (Glaziou et al., 2018). It is possible to note that about 10 million people fall ill with TB each year globally, and it is a stable trend in recent years (World Health Organization [WHO], 2019). Tuberculosis affects both HIV-positive and HIV-negative people, both sexes in all age groups, but men under 15 years old accounted for most of the TB cases in 2018 estimated at 57% (WHO, 2019). Moreover, not only tuberculosis is still a threat, but drug-resistant TB is also a significant issue. According to the World Health Organization, three countries share the global drug-resistant TB burden: India (27%), China (14%), and Russia (9%) (WHO, 2019). As far as the global TB situation is concerned, India also has the highest rates of TB, followed by China, Indonesia, and the Philippines (WHO, 2019). Thus, South-East Asia is the region most affected by tuberculosis.
Risk Factors
Several factors contribute to the spread of this infectious disease. Firstly, it is necessary to note the TB prevention methods are not available worldwide. Usually, the Bacillus Calmette–Guérin (BCG) vaccine is considered an effective preventative method against tuberculosis and recommended to be applied to all healthy babies in countries with higher tuberculosis rates (WHO, 2019). The good news is that 153 countries reported that the BCG vaccine became a part of a standard program of child immunization in 2018 (WHO, 2019). However, this is still not enough as financial situations in developing countries are not stable, and health-care systems are different. Health-care systems in some countries are not able to diagnose TB or treat it correctly. For example, in India, Indonesia, and Nigeria, the number of underreported detected TB cases is extremely high (WHO, 2019). It means that underdiagnosis and challenged access to health care in these countries is a big problem and a risk factor for the continuing spread of the disease.
Nevertheless, access to health care and the quality of treatment are not the only factors contributing to the resurgence of TB. Researchers note that people with chronic diseases have a higher risk of TB infection (Glaziou et al., 2018). For example, according to the recent research, having HIV or diabetes increases the risk of obtaining active tuberculosis (Glaziou et al., 2018). Among other factors, there are undernutrition, smoking, or alcohol abuse (Glaziou et al., 2018). Researchers also state that “patients infected with HIV had higher odds of TB diagnosis at death and death during TB treatment than patients who were HIV negative” (Hannah, Miramontes, & Gandhi, 2017, p. 373). It means that countries with a statistically high HIV-positive population are at risk as well as the prevalence of cigarettes or alcohol can affect the decline in TB incidents around the world in the future.
Another factor contributing to the spread of TB is drug resistance. There are new types of tuberculosis that are resistant to antibiotics. Although scientists work on new methods of treatment of these drug-resistant TB types, only one in three people are enrolled in the latest treatment programs (WHO, 2019). According to the World Health Organization, the global drug-resistant TB treatment success rate is 56% (WHO, 2019). Although scientists made good progress, the world still has not overcome tuberculosis.
The US Statistics and TB Control Challenges
Although TB is not eliminated in the USA, the government achieved much success in lowering TB rates in the past 30 years. According to researchers, tuberculosis rates have drastically decreased since 1993 (LoBue & Mermin, 2017). In 2018, 9,025 cases of TB were reported in total, with almost 70% of them among non-U.S.-born people (“Trends in tuberculosis,” 2018). The state of Georgia has also experienced a slight decrease in TB cases in recent years, with 53% of cases among non-U.S.-born people in 2017 (Georgia Department of Public Health, 2017). It means that most infected people might have obtained this disease in countries with high TB rates before moving to the USA. In general, the state of Georgia is no exception to the average U.S. TB statistics. As compared to the worldwide statistics, the U.S. is not included in the list of countries with high TB cases rates (WHO, 2019). The U.S. has a significant potential to eliminate TB in the future.
Like many other countries, the U.S. is challenged by TB drug-resistance. The researchers note that the number of drug-resistant TB cases has remained unchanged for the last 20 years (“Trends in Tuberculosis,” 2018). The state of Georgia experienced 3 cases of drug-resistant TB in 2017, and one of them was born in the country with high TB burden (Georgia Department of Public Health, 2017). Besides further research on the new TB antibiotics, it is also necessary to work on the prevention methods. For example, TB testing for high-risk groups such as health care workers, people traveling to the countries with high TB rates, or homeless people and prisoners is very important.
Conclusion
Although tuberculosis is not eliminated worldwide, much success has been achieved in the past decades. There is a stable downward trend in TB rates worldwide due to effective prevention methods such as vaccines, as well as TB antibiotics research. However, the world is still challenged by TB drug-resistance and faces future problems with TB treatment as it correlates with chronic diseases. The highest TB rates around the world are still in East-Asia. Although the US does not suffer as much as developing countries, it is necessary to work on eliminating TB in the USA.
References
Georgia Department of Public Health (2018).2017 Georgia tuberculosis report.Web.
Glaziou, P., Floyd, K., & Raviglione, M. C. (2018). Global epidemiology of tuberculosis. Seminars in Respiratory and Critical Care Medicine, 39(3), 271-285.
Hannah, H. A., Miramontes, R., & Gandhi, N. R. (2017). Sociodemographic and clinical risk factors associated with tuberculosis mortality in the United States, 2009-2013. Public Health Reports, 132(3), 366-375.
LoBue, P. A., & Mermin, J. H. (2017). Latent tuberculosis infection: the final frontier of tuberculosis elimination in the USA. The Lancet Infectious Diseases, 17(10), e327-e333.
Trends in tuberculosis, 2018. (2019). Web.
World Health Organization (2019). Global tuberculosis report. Executive summary 2019.