Fighting TB: Not a one-way solution

After reviewing a number of studies that attempt to explain the historical decrease of tuberculosis (TB), I could argue that the decline of TB incidence and mortality was due to a combination of both improvement of general social conditions and targeted public health interventions.

After being one of the main causes of death in the United Kingdom in the late 17^th century, and reaching a peak in around 1780 when an estimated 1.25% of the population died each year from TB, its incidence started to decline at the beginning of the 19^th century. This declining was observed long before the discovery of M. tuberculosis and a century before the use of antibiotics and other specific therapies. Therefore it’s argued that general improvements in the conditions of living, including better sanitation and nutrition, contributed significantly to the decline in TB incidence and mortality.

One of the leader researcher towards this argument is Thomas McKeown. Since the 1960s he’s been promoting the idea that the decline in TB mortality is due to the incremental changes in people’s standard of living, mainly better nutrition, thus minimizing the impact and effectiveness of direct public health programs, such as sanitary reforms, vaccination and segregation of infected people. For him, “the main reasons for improvement in health in probable order of importance were: a decline in the birth rate; a rise in the standard of living, first in food supplies […]; removals of specific hazards in the physical environment; and specific measures of preventing and treating disease in the individual.” [1]

This idea was revolutionary and changed the way of studying population’s health determinants, putting more emphasis in socio-economic factors than in curative medicine.

Other authors promote the use of multifactorial models to explain the downward trend of TB and other diseases. For example, Szreter cites the “existence of inter-current infections and occupational hazards that weakened host resistance to TB and of overcrowding and poor ventilation in work and home environments that enhanced transmission of the disease”. And then suggests that “these factors were removed not only by rising real wages and better nutrition but by political and social action associated with the public health movement” [2].

For Newsholme, on the other hand, segregation was an effective measure against TB, and he embraced to the idea that “targeted public health actions –including housing policies and public education leading to behavioral changes- could effectively contribute toward the decline in TB incidence and mortality”, and that these programs were “politically feasible, unlike broader social reform affecting nutrition and poverty.” [2]

There’s also evidence that the practice of directly observed therapy (DOT) and DOT short course (DOTS) is effective to control TB incidence, mainly preventing antibiotics resistance. This practice was promulgated by the WHO as its strategy for TB control.

There are many other studies that give us different approaches to the matter, leading me to think that there’s no single formula to explain the evolution of TB, but a combination of factors. It’s true that income is a powerful means to improve people’s health, by providing access to better nutrition, sanitation, housing, and even medicines or treatments for medical conditions. Therefore, poverty and income inequalities are determinants of a population’s wellbeing. But as I said, income is a means, and what’s important is the use and benefits one could obtain with the disposable income. That’s why I believe that wages alone or GDP per capita don’t determine the wellbeing of a population. Money should be put to good use, from the individual point of view, but also from governments that are in charge of the health of the population.

Some articles draw a parallel between high income countries, high health expenditures and low TB incidence [3]. This could be true in part, but there’re countries with modest per capita incomes that show as good health indicators as much richer countries. As I said earlier, money should be spent wisely, meaning from the broadest policies such as education or sanitation, to targeted health programs and research. I believe that a combination of socio-economic improvements and targeted health interventions are applicable as determinants of the declining of TB incidence and mortality.

Do you think that the political environment has any influence in the population’s health? Which political system you believe provides a more favorable environment?

References

[1] McKeown, Thomas, “A Sociological Approach to the History of Medicine”

[2] Fairchild, Amy and Oppenheimer, Gerald. “Public health nihilism vs pragmatism: History, politics, and the control of tuberculosis”. In American Journal of Public Health; Jul 1998; 88, 7; ABI/INFORM Global, pg. 1105 http://www.collphyphil.org/APHA%20Readings/Day%202%20Readings/FairchildandOppenheimer.pdf

[3] Paul D. van Helden, “The economic divide and tuberculosis. Tuberculosis is not just a medical problem, but also a problem of social inequality and poverty”. http://www.nature.com/embor/journal/v4/n6s/full/embor842.html

Szreter, Simon. “Rethinking McKeown: The Relationship Between Public Health and Social Change.” http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1447152

Colgrove, James. “The McKeown Thesis: A Historical Controversy and Its Enduring Influence” http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1447153

Evans, Robert. “Thomas McKeown, meet Fidel Castro: Phisicians, Population Health and the Cuban Paradox.” http://www.longwoods.com/product.php?productid=19916

What does it take to have a better educated Guatemala?

In the past, when Guatemala’s economy relied on agriculture (plantain production and exports), economic growth was achieved through an educated elite and a large amount of unskilled workers. But the current economic model of services demands workers with specialized skills and higher education. In 2002, 25% of workers had no formal education; 49% some primary education; 21% some secondary education, and only 5% some tertiary studies.

A study of the effects of education on economic growth in Guatemala [1] showed that the country needs a better educated labor force in order to achieve a higher economic growth. In that sense, in Guatemala’s production function, human capital variables explain more than 50% of output growth, while physical capital explains only 32%. The level of education that has higher return in productivity is secondary education, followed closely by primary education, and in third place, tertiary education. But in aggregate, workers with secondary and tertiary education together have a greater impact in economic growth than those who only achieved primary.

Education could be a powerful tool to overcome poverty of income. It was estimated that ‘one additional year of schooling increases income per worker by approximately 18.4%.’[1] But we must not disregard that secondary education is key not only for addressing poverty, but also for improving equality, agency, empowerment and participation among the population.

The principal features and challenges of post-primary education in Guatemala are as follows:

- A 20 year-old has only 4.3 years of education on average.

- In secondary education, the gross enrollment rate is 55%, and the net rate is only 26%, while the average in Latin America of the net enrollment rate is 64%.

- Inequalities in access related to gender and ethnicity. Gross secondary enrollment rates in Grades 7-9 (2005): Guatemala 55%; Boys 59%, Girls 51%; Indigenous 26%, Non-indigenous 74%.

- Secondary school is concentrated in urban areas, and rural and indigenous populations have fewer opportunities.

- Secondary enrollment attending private schools is high: 74%.

- Quality of education: ‘learning level is very deficient overall, and especially in rural secondary education models.’ [2]

- Only 22 out of 100 children complete primary education on time, a ‘bottleneck’ for expanding secondary school enrollment.

- Low retention. Gross completion rate in Grade 9: 46%

- Overage and repetition. Enrollment rates drop pronouncedly between ages of 13 and 16, but, because of repetition and overage, these dropouts occur mostly during primary school. 40% of 13-15 year olds were in primary school.

- Teachers are trained during secondary education only (Grades 10-12), thus low quality in primary and secondary education are intertwined.

It seems that the main challenge to increase enrollment in secondary education would be by addressing the low efficiency of primary education through an integrated strategy. ‘The strategic choice of the Government of Guatemala is to start reforms at the secondary education level, but to continue to support primary education, complementing long-term general quality improvements (such as improving the quality of pre-school and the first cycle, Grades 1-3, and support teacher professional development) with short-term efficiency solutions (such as accelerated learning and promotion for overage students).’[2]

Investment in education thus should be a priority. With only 1.7% of GDP invested in education, not much can be addressed. The main justification for public financing relies on the “positive externality” argument [3], especially in poorer countries with high inequalities such as Guatemala. With a gross enrollment rate in secondary school of 55%, and 74% attending private schools, inequalities will rise if secondary education is only a luxury for a few.

References

[1] Loening, Josef L., 2005. Effects of Primary, Secondary and Tertiary Education on Economic Growth. Evidence from Guatemala. The World Bank, Washington D.C. and Ibero-America Institute for Economic Research, University of Goettingen.

[2] World Bank, 2006. Project Guatemala: Education Quality and Secondary Education Project. Project Appraisal Document.

[3] di Gropello, Emanuela (Ed.), 2006. Meeting the Challenges of Secondary Education in Latin America and East Asia. Improving Efficiency and Resource Mobilization. The World Bank.