Poverty Prevention and Antimicrobials: The Impact on Infectious Diseases in Developing Countries by Adebayo Lamikanra, Professor, Obafemi Awolowo University, APUA Nigeria Chapter Leader
Disovery & Stewardship of Narrow Spectrum Antibiotics by Philip Walson, M.D., Editor-in-Chief of Clinical Therapeutics
Poverty, Prevention and Antimicrobials: The Impact on Infectious Diseases in Developing Countries (p. 10)
Adebayo Lamikanra, Professor
Obafemi Awolowo University
APUA Nigeria Chapter Leader
The life expectancy of a child born in Nigeria today is less than fifty years. In stark contrast, a child born in Japan, for example, can confidently expect to live for at least eighty years, significantly in excess of half a life time longer than his Nigerian counterpart. This comparison, horrifying as it is, tells half of the story because no less than 94 in every 1,000 babies born in Nigeria will die before their first birthday and 138 will not be alive to celebrate their fifth birthday. Comparable figures for Japan are 2.79 years and 3.3 years respectively. There are myriad reasons why the Nigerian figures are so dismal, but perhaps the most telling statistic is that 43.1% of fatalities in third world countries as a whole are due to infections, compared with 2.67% for North America. The import of this difference is that, whilst death in the affluent countries is due mainly to chronic and degenerative changes caused by old age, most deaths in Nigeria and other tropical countries are due to infections that are likely to attack young people, and in doing so, make it impossible for them to live very long. This means however that a much brighter picture is bound to be achieved if infections were to be adequately controlled through prevention, blanket vaccination cover, improvements in social hygiene infrastructure, and of course, effective chemotherapy. The point needs to be made at this juncture that the hot and humid tropical environment is, in the absence of other considerations, one that is especially conducive to the proliferation of all forms of microbial life. Some of the most life-destroying microbes—e.g., those responsible for malaria, lassa fever, ebola, and sleeping sickness are confined to the tropics, and virtually all other infections are very strongly associated with these regions. The issue of containing these infections is compounded by the material poverty that is characteristic of countries in the tropics—a baffling level of poverty given the abundance, if not profusion, of natural resources: crude oil, solid minerals, forest products, agricultural products (and their potential) among others with which the tropics are endowed. On the contrary, conditions in these developing countries suggest that the quality of life in those countries has slipped, in some cases glaringly so.
It is with the above considerations in mind that one should contemplate the challenge of antimicrobial chemotherapy in the tropics. First, there are simply more infections to be dealt with, and with high ambient temperatures, the rate of growth and consequent microbial evolution is very high, such that the development of resistance to antimicrobial agents should be expected to be significantly higher than that found in countries situated in temperate zones. Interestingly, the possibility of this happening has received scant attention.
The introduction of antibiotics into clinical practice has had a major impact on the internal environment of the human body. As with any environment, this has led to the imposition of stiff selective pressures, leading to the development of new variants of microorganisms, which in most cases are not biochemically nor morphologically different from those that remain sensitive. One major challenge of chemotherapy in Nigeria and other developing countries is the identification of these resistant organisms, followed by an adequate response.
Although genuinely new antibiotics are not being developed anywhere near the rate at which they are required, patients in the affluent developed countries have access to advanced anti-infective agents that are way beyond the reach of people in the developing countries. The latter have to wait for patents on new drugs to expire, and are instead treated with pharmaceutically inferior generic versions of drugs which have been heavily used in Europe and the United States before their eventual introduction into the drug markets of the developing countries. A case in point is ciprofloxacin, which because of its high cost, was very sparingly used in Nigeria before 2003 when it was still patented. Subsequently, there was an explosion in its use as no less than fifty different generic brands of the drug became available in Nigeria within a period of two years. In our laboratory study of commensal E. coli from students of the Obafemi Awolowo University in Nigeria, the prevalence of antibiotic resistance rose from low single digits to 20% in 2005. Ciprofloxacin is now regarded as the drug of choice in antibacterial chemotherapy in Nigeria, but given the extant conditions, it cannot be long before the effectiveness of this drug becomes heavily compromised, as indeed has happened to other antibiotics in the past.
The issue of acquired antimicrobial resistance has now moved out of the pages of relatively inaccessible scientific journals and has been dressed in lurid garb in large circulation newspapers, a testament to its new-found news worthiness. Many of the stories concerning the ‘superbugs’ are sensational and perhaps more disturbing than they should be, but they boost circulation figures and so will run repeatedly. Even the most respectable of these papers finds it impossible to treat this subject with the circumspection that it deserves. Stories concerning the grave challenges facing the use of antimicrobial agents in third world countries are far less sensational than the closure of a few wards caused by MRSA or Clostridium difficile in a New York or London hospital, but are sure to bring more misery, sudden death and ever increasingly lower quality of life to people in developing countries.
Guest Editorial: Disovery & Stewardship of Narrow Spectrum Antibiotics
APUA board member Philip Walson, M.D., who is the Editor-in-Chief of Clinical Therapeutics, provided his comments on the recent article, “Optimer Seeks Quick Green Light From FDA for Antibiotic Against Deadly Bug”
It is too early to be sure what the future holds for this new antibiotic, especially compared to much cheaper generic drugs like metronidazole. However, the development of any new antibiotic is welcome and development and commercialization of any so called “narrow spectrum” antibiotics is especially encouraging. The company will now have to convince physicians to adopt a totally new strategy to treating infections — one that includes first making a clear, specific diagnosis and then using a drug designed to treat only the one diagnosed infection and not selecting a “shotgun” approach to all possible infectious agents. If they are successful this should both increase the use of this antibiotic and help to combat excessive, non-specific antibiotic use by training physicians to think differently about the use of antibiotics. This includes considering the development of resistance as a major outcome variable in antibiotic selection. Such thinking can only be welcomed given the rapidly developing rates of multidrug antibiotic resistance which is due at least in part to the overuse of broad spectrum antibiotics. Optimer’s new antibiotic received unanimous approval of the FDA Anti-Infective Advisory Committee on April 5, 2011. The FDA approved Optimer Pharmaceuticals' new antibiotic for treating Clostridium difficile on May 27, 2011.
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