Hepatitis C Information Central

Hepatology, February 1999, p. 610-611, Vol. 29, No.2
Correspondence
Global Warming and Therapeutic Intervention for Hepatitis B and C Virus Infection

To the Editor:

Therapeutic intervention with interferons, Hepatitis B immune globulin, lamivudine, and ribaverine has been accompanied by clearance of viral nucleic acids from serum and hepatic tissue. Their efficacy could be seriously affected in the face of impending global warming and frequent El Niño effects. Interferons and Hepatitis B immune globulin have to be stored around 2°C to 8°C, whereas lamivudine or ribaverine should not be exposed to a temperature above 25°C.¹ Any inadvertent exposure to higher than stipulated temperature could reduce their therapeutic efficacy in industrialized and developing countries. Furthermore, quantification of viral nucleic acid, genotyping, and sequencing are integral components for antiviral chemotherapeutic interventions: serial assays alone would vindicate the efficacy of a therapeutic regimen. The desired temperature range for storage of different molecular biology products is between 70°C and around 0°C. ICN Pharmaceuticals Inc., (Costa Mesa, CA) recommend storing reverse transcriptase at 70°C, five other groups of products (mainly enzymes) at 20°C, and yet another seven groups at around 0°C.

A new record in the global temperature was established during July 1998, when the average global temperature reached was 15.5°C, and July 1998 was the hottest month during the past 120 years.² Such high ambient temperature if accompanied by high humidity would involve enormous heat transmission to different antihepatitis B or C virus therapeutic agents as well as the components of molecular biological assay kits needed for monitoring therapeutic response in patients.

During the 1995 heat wave in Chicago, the maximum temperature recorded was 40°C, although the heat index, an estimate of evaporative and radiative transfer of heat, was 48.3°C.³ In developing countries, heat waves are accompanied by poor electricity supplies that disturb the working of electricity operated appliances meant for maintaining temperature at appropriate levels.⁴

The inimical effects of high temperature and humidity^2,3 on different therapeutics as well as molecular biology reagents used to monitor antiviral therapy could be best tackled by stabilization against harsh environment. Efforts have been directed to stabilize live vaccines by incorporating trehalose, deuterium oxide, pirodavir, or compounds based on electrostatic interventions.⁵ Availability of one-to two-step assay procedures that do not require costly equipment and trained personnel, would be vital for strengthening quality control on antihepatitis B or C viral therapeutics. Such assays would assist quantification of active ingredients of therapeutics in the premises of the physician prescribing various drugs. A semiquantitative, acetaminophen-specific spot test for screening quality of acetaminophen in the field has been very meritorious.⁶

Full stabilized antihepatitis B or C viral therapeutic agents that would withstand environment rigors would ensure that every patient received full quantum of the prescribed therapeutic agent. Incorporation of stabilizers in molecular biology reagents would ensure full use of such reagents in the face of high humidity and temperature linked with impending global warming.^2,3

Surely, such therapeutics and diagnostic reagents against Hepatitis B or C virus would eliminate erroneous laboratory data, poor therapeutic response, and emergence of resistant viral populations attributable to poor quality therapeutic agents.

Subhash C. Arya, M.B.B.S., Ph.D. Centre for Logisstical Research and Innovation M-122 (of part 2), Greater Kailash-II New Delhi, 110048 India

REFERENCES

1.	Physicians' Desk Reference. 51st Edition. Medical Economics Data. Montvale, 1997.
2.	United States Environmental Protection Agency. Global warming. Vice President Gore announces new data showing July 1998 was the hottest month on record. August 10, 1998.
3.	Heat-related mortality Chicago, July 1995. MMWR 1995;44:577-579.
4.	Kumar S. India's heat wave and rains result in massive death toll. Lancet 1998;351:1869.
5.	New Approaches to Stabilisation of Vaccine Potency. In: Brown F, ed. Basel: Karger 1996; 161-166, 173-180, 193-199, 207-217.
6.	Roy J, Saha P, Sultana S, Kenyon AS. Rapid screening of marketed paracetamol tablets: use of thin layer chromatography and a semiquantitative spot test. Bull WHO 1997;75:19-22.

Copyright © 1999 by the American Association for the Study of Liver Diseases.