Global response to antimicrobial resistance.

variables explain more than half of the differences in urban HIV prevalence between countries. Understanding societal variables (such as caste, gender relations, power in sexual relationships, etc.) may help in determining the future spread of the epidemic and contribute to explaining the local effectiveness of public health interventions – such as programmes to reduce risk for sex workers. In addition to targeted behaviour change interventions, the HIV epidemic in India may be contained through a multisectoral approach that takes into account the highly diverse nature of behavioural, social and economic risk and vulnerability. Improved under- standing of the contribution of societal variables is necessary in order to produce models that reflect the impact of addressing these variables on overall HIV incidence in India. n Prasanna Kumar,1 Sarah J. Hawkes,2 & Kent Buse3 Conflicts of interest: none declared. 1. Nagelkerke NJD, Jha P, de Vlas SJ, Korenromp EL, Moses S, Blanchard JF, et. al. Modelling HIV/AIDS epidemics in Botswana and India: impact of interventions to prevent transmission. Bulletin of the World Health Organization 2002;80:89-96. 2. Hawkes S, Santhya KG. Diverse realities: sexually transmitted infections and HIV in India. Sexually Transmitted Infections. In press 2002. 3. Jana S, Bandyopadhyay N, Mukherjee S, Dutta N, Basu I, Saha A. STD/HIV intervention with sex workers in West Bengal, India. AIDS 1998; 12 (Suppl B):S101-8. 4. Raising the sights: better health systems for India’s poor. Washington (DC): World Bank; 2001. Report No. 22304. 5. Sumartojo E. Structural factors in HIV prevention: concepts, examples, and implications for research. AIDS 2000;14 (Suppl)1:S3-10. 6. Over M. The effects of societal variables on urban rates of HIV infection in developing countries: an exploratory analysis. In: AinsworthM, Fransen N, Over M, editors. Confronting AIDS: evidence from the developing world. Washington (DC): World Bank; 1998. Global response to antimicrobial resistance Editor – In a recent issue of the Bulletin, Smith & Coast (1) succinctly reviewed the emerging global scourge of anti- microbial resistance (AMR). Neverthe- less, their strategies for containment of the emergence and dissemination of AMR in Table 1 do not include an evaluation of the potency and bio- availability of antibiotics, probiotics or vaccines being offered to the public worldwide. Plausible host factors or pharmacokinetics of drugs have also been ignored. Antimicrobial agents require con- stant storage within a controlled temperature range: from either subzero to 2–8 oC, or 15 to 25–30 oC (2). Inadvertent exposure to extremes of temperature or humidity would alter their potency. This was evident during a Nigerian field trial when the active ingredients in 48% of the samples of common medicines were found to be outside the limits specified by the British Pharmacopoeia (3). Identical scenarios may occur with antimicrobial formula- tions elsewhere. Such formulations would be ineffective against microbial replication and, being lower than the required antibiotic quantum, encourage selection and dissemination of resistant microbes. Obviously, any response at local, national, regional or global levels to manageAMRwill not be effective unless losses in potency and bioavailability of antimicrobial agents are monitored regularly, including during their admin- istration. Simple assay formats that could accomplish qualitative and quan- titative analysis of antimicrobial agents in the clinical and household setting should be standardized. Recently, Green et al. (4) proposed a quick and simple field test requiring few chemicals and no sophisticated equipment to identify artesenuate, an antimalarial drug. Iden- tical tests for frequently used anti- microbial agents would confirm the quality of the antibiotics or probio- tics being consumed. The addition of chemical stabilizers may well help retain the potency of antibiotics and probiotics in adverse environments. The least stable of the common childhood vaccines, oral polio vaccine is stabilized by the addition of pirodavir and deuterium oxide (5). Pre-stabilization of therapeu- tics would not only prevent emergence and dissemination of AMR, but be cost- effective. Host-induced factors could alter the efficacy of therapeutic agents offered against microbial infection. For example, any concurrent formulations of antacid containing magnesium hydroxide or aluminium hydroxide alter the efficacy of orally administered therapeutic agents. The bioavalibility of ciprofloxacin would be reduced drasti- cally with a concurrent administration of milk (6). Such eventualities cannot be ignored and should be eliminated by assaying the maximum drug plasma concentration, including the area under the assay curve. Undoubtedly, simpler tests to measure drug concentration in saliva or urine, rather than in blood, could be employed. These tests would be important assets for the global effort to tackle AMR (1). n Subhash C. Arya4 Conflicts of interest: none declared. 1. Smith RD, Coast J. Antimicrobial resistance: a global response. Bulletin of the World Health Organization 2002;80:126-33. 2. Physicians’ desk reference. 55th edition. Medical Economics Company. Montvale, 2001. 3. Taylor RB, Shakoor O, Behrens RH, et al. Pharmacopoeial quality of drugs supplied by Nigerian pharmacies. Lancet 2001;357:1933-6. 4. Green MD, Mount DL, Wirtz RA, White NJ. A colorimetric field method to assess authenticity of drugs sold as the antimalarial artesenuate. Journal of Pharmaceutical and Biomedical Analysis 2000;24:65-70. 5. Verheyden B, Andrus K, Rombart B. Capsid and RNA stabilization of oral poliovaccine. Vaccine 2001; 9:1899-905. 6. Hoogkarmer JFW, Kleinbloesem CH. The effect of milk consumption on the pharmakinetics of fleroxin and ciprofloxacin. Drugs 1995;49 (Suppl 2):346-8. 1 Assistant Director of Health Services (AIDS), Kerala State AIDS Control Society, India. 2 Honorary Lecturer, London School of Hygiene and Tropical Medicine, London, England. 3 Assistant Professor, Yale University School of Medicine, Room 301, 60 College Street, New Haven, CT 06520-8034, USA. Correspondence should be addressed to this author (email: kent.buse@yale.edu). 4 Research Physician, Centre for Logistical Research and Innovation, M-122 Greater Kailash – Part 2, New Delhi 110048, India (email: subhashji@vsnl.net). 420 Bulletin of the World Health Organization 2002, 80 (5) Letters