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Can we stand the heat?
THE LANCET I
I
Can we stand the heat? S B Squire Tropical medicine was born in the friction between man and a natural environment over which he had limited influence. It concentrated on diseases maintained and borne by vectors dependent on that environment. With over-population, industrialisation, urbanisation, and war, man himself is increasingly the dominant feature of the landscape. A new interaction is afoot in the tropics: a friction between man and a crowded, poor environment in which diseases conveyed directly between human beings, such as HIV and tuberculosis, have reached frightening dimensions. This new friction has not replaced the old, merely added to it. Indeed poverty and population have conspired, as shown by the outbreak of Ebola fever
(WHO
Wkly Epidemiol Rec
1995; 25: 241), to allow diseases presumed to have animal reservoirs to emerge in the human community. Much of the friction is not new to this year, but the murmurs of 1994
(Trans R Soc Trop Med Hyg 1994; 88: 4) are louder in 1995
(BMJ 1995; 311: 860). Can tropical medicine, in its present form, stand the heat? Some of the answer lies in what has, or has not, been achieved in the last year against the most important microbial causes of morbidity and mortality world wide. Diseases that reach medical attention The e a r s of t h e h i p p o p o t a m i are only representatives of a much larger, affected, but less-symptomatic population. In Central Africa they say that clinicians only ever see the "ears of the hippopotami" (figure). It can be argued that chewing at these ears is futile; better to concentrate on the bulk below the waterline. This may not be straightforward. Aisu reports that implementing chemoprophylaxis for HIV-1 infected individuals with latent Mycobacterium tuberculosis infection has proved difficult in the developing world and the optimism surrounding the malaria vaccine SPf66 (Lancet 1994; 344: 1175) has been tempered by D'Allesandro's trial. No, the real message of the year is that concentrating on the ears is not entirely a waste of effort. An assault on the ears of one beast may even be a useful way of getting
Lancet 1995; 346 (suppl): 25 Liverpool School of Tropical Medicine, Pembroke Place, Liverpool 1.3 5QA, UK (S B Squire MD) Vol 346 ° December 23/30, 1995
at another beast. 1995 saw the publication of Grosskurth's evidence that control of sexually transmited diseases in a rural community may lead to a reduced incidence of HIV infection. Indeed, in some instances, amputation of the ears may be a good way to slay the beast outright. The best example is tuberculosis. Finding and curing symptomatic sputum-smear-positive pulmonary cases is the core activity of tuberculosis control. Unfortunately the HIV pandemic threatens this activity at every level x .... (De Cock). Thus, where co-infection with M tuberculosis and HIV- 1 is common, health professionals are overworked, laboratory services are inundated with sputa, and patients abscond from treatment. Whatever organisational and managerial solutions can be offered (Lancet 1995; 346: 809, Lancet 1995; 345: 1545) we urgently need a sensitive and specific means of diagnosing tuberculosis on the spot and a shorter, safer treatment regimen. We must examine simple ways (Trans R Soc Trop Med Hyg 1995; 89: 191) to improve the yield from microscopy of a single sputum specimen delivered on the spot. If it is to stand the heat, tropical medicine must keep its attention on the source of the conflagration, and remember that there is more to disease that that which presents at the clinic. Key references for 1 9 9 5 Aisu T, Raviglione M C , v a n - P r a a g E, et al. P r e v e n t i v e c h e m o t h e r a p y for H I V - a s s o e i a t e d tuberctdosis in Uganda: an operational a s s e s s m e n t at a voluntary counselling and testing center. A I D S 1995; 9: 267-73. D ' A l l e s a n d r o U~ L e a c h A, D r a k e l e y CJ, et al. Efficacy t r i a l o f m a l a r i a v a c c i n e SPf66 in G a m b i a n infants. ~.ancet 1995; 346: 462-67. D e Cock KM, Wilkinson D. Tuberculosis control in r e s o u r c e - p o o r countries: alternative a p p r o a c h e s in the e r a o f HIV. L a n c e t 1995; 346: 675-77. G e b r e N, K a r l s s o n U, Jonsson G, et al. I m p r o v e d m i c r o s c o p i c a l diagnosis o f p u l m o n a r y tuberculosis in d e v e l o p i n g countries. T r a n s R Soc Trop M e d H y g 1995; 89: 191-93. G r o s s k u r t h J, M o s h a F, Todd J, et al. I m p a c t o f i m p r o v e d t r e a t m e n t o f sexually t r a n s m i t t e d diseases on H I V i n f e c t i o n ill rural Tanzania: r a n d o m i s e d controlled trial. L a n c e t 1995; 346: 530-36.
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I
Can we stand the heat? S B Squire Tropical medicine was born in the friction between man and a natural environment over which he had limited influence. It concentrated on diseases maintained and borne by vectors dependent on that environment. With over-population, industrialisation, urbanisation, and war, man himself is increasingly the dominant feature of the landscape. A new interaction is afoot in the tropics: a friction between man and a crowded, poor environment in which diseases conveyed directly between human beings, such as HIV and tuberculosis, have reached frightening dimensions. This new friction has not replaced the old, merely added to it. Indeed poverty and population have conspired, as shown by the outbreak of Ebola fever
(WHO
Wkly Epidemiol Rec
1995; 25: 241), to allow diseases presumed to have animal reservoirs to emerge in the human community. Much of the friction is not new to this year, but the murmurs of 1994
(Trans R Soc Trop Med Hyg 1994; 88: 4) are louder in 1995
(BMJ 1995; 311: 860). Can tropical medicine, in its present form, stand the heat? Some of the answer lies in what has, or has not, been achieved in the last year against the most important microbial causes of morbidity and mortality world wide. Diseases that reach medical attention The e a r s of t h e h i p p o p o t a m i are only representatives of a much larger, affected, but less-symptomatic population. In Central Africa they say that clinicians only ever see the "ears of the hippopotami" (figure). It can be argued that chewing at these ears is futile; better to concentrate on the bulk below the waterline. This may not be straightforward. Aisu reports that implementing chemoprophylaxis for HIV-1 infected individuals with latent Mycobacterium tuberculosis infection has proved difficult in the developing world and the optimism surrounding the malaria vaccine SPf66 (Lancet 1994; 344: 1175) has been tempered by D'Allesandro's trial. No, the real message of the year is that concentrating on the ears is not entirely a waste of effort. An assault on the ears of one beast may even be a useful way of getting
Lancet 1995; 346 (suppl): 25 Liverpool School of Tropical Medicine, Pembroke Place, Liverpool 1.3 5QA, UK (S B Squire MD) Vol 346 ° December 23/30, 1995
at another beast. 1995 saw the publication of Grosskurth's evidence that control of sexually transmited diseases in a rural community may lead to a reduced incidence of HIV infection. Indeed, in some instances, amputation of the ears may be a good way to slay the beast outright. The best example is tuberculosis. Finding and curing symptomatic sputum-smear-positive pulmonary cases is the core activity of tuberculosis control. Unfortunately the HIV pandemic threatens this activity at every level x .... (De Cock). Thus, where co-infection with M tuberculosis and HIV- 1 is common, health professionals are overworked, laboratory services are inundated with sputa, and patients abscond from treatment. Whatever organisational and managerial solutions can be offered (Lancet 1995; 346: 809, Lancet 1995; 345: 1545) we urgently need a sensitive and specific means of diagnosing tuberculosis on the spot and a shorter, safer treatment regimen. We must examine simple ways (Trans R Soc Trop Med Hyg 1995; 89: 191) to improve the yield from microscopy of a single sputum specimen delivered on the spot. If it is to stand the heat, tropical medicine must keep its attention on the source of the conflagration, and remember that there is more to disease that that which presents at the clinic. Key references for 1 9 9 5 Aisu T, Raviglione M C , v a n - P r a a g E, et al. P r e v e n t i v e c h e m o t h e r a p y for H I V - a s s o e i a t e d tuberctdosis in Uganda: an operational a s s e s s m e n t at a voluntary counselling and testing center. A I D S 1995; 9: 267-73. D ' A l l e s a n d r o U~ L e a c h A, D r a k e l e y CJ, et al. Efficacy t r i a l o f m a l a r i a v a c c i n e SPf66 in G a m b i a n infants. ~.ancet 1995; 346: 462-67. D e Cock KM, Wilkinson D. Tuberculosis control in r e s o u r c e - p o o r countries: alternative a p p r o a c h e s in the e r a o f HIV. L a n c e t 1995; 346: 675-77. G e b r e N, K a r l s s o n U, Jonsson G, et al. I m p r o v e d m i c r o s c o p i c a l diagnosis o f p u l m o n a r y tuberculosis in d e v e l o p i n g countries. T r a n s R Soc Trop M e d H y g 1995; 89: 191-93. G r o s s k u r t h J, M o s h a F, Todd J, et al. I m p a c t o f i m p r o v e d t r e a t m e n t o f sexually t r a n s m i t t e d diseases on H I V i n f e c t i o n ill rural Tanzania: r a n d o m i s e d controlled trial. L a n c e t 1995; 346: 530-36.
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