malaria among international travellers. Can Comm Dis Rep 1995;
probably a change in living conditions. Even in the poorest
21, S3: 1–18.
US communities, most people now live and work in air-
Krogstad DJ. Plasmodium species (malaria). In: Mandell, Douglas,
conditioned buildings, or are at least protected by insect
and Bennett’s principles and practice of infectious diseases. 4th ed.
screens. In addition, the spacing of houses and other
New York: Churchill Livingston, 1995: 2415–27.
buildings has increased because modern urban areas haveevolved around the motor vehicle. As a result, populationdensity is much lower than in the past, a major impediment
Global warming and mosquito-borne disease
to transmission. Events such as the dengue pandemic that
affected the Caribbean, Central America, and Mexico in1995 support this explanation. 74 000 cases were reported
SIR—In your June 8 editorial1 you raise the issue of the
from the region (Pan-American Health Organisation,
impact of global warming on health. Speculations on the
unpublished data), including 4479 from Tamaulipas state,
effect of global warming in the USA frequently include
on the Texas border. Of these, 2361 were from Reynosa, a
discussion of mosquito-borne diseases such as malaria,
city contiguous with Hidalgo, Texas, but only seven
yellowfever, and dengue.2 Some have suggested that rising
autochthonous cases were reported in the entire state of
temperatures will expand the geographical range of vector
Texas.5 Thus, unless living conditions are drastically
mosquitoes, increase their rate of development, and reduce
changed, global warming is unlikely to give rise to major
the extrinsic incubation time of their pathogens. The
epidemics of tropical mosquito-borne disease in the USA.
implication is that both the mosquitoes and the diseases willemerge from the tropics and give rise to epidemics in the
USA. Such predictions ignore the complex dynamics of
Dengue Branch, Division of Vector-Borne Infectious Diseases, National Centre forInfectious Diseases, Centers for Disease Control and Prevention, San Juan
mosquito-borne infections: climate and weather are
Laboratories, San Juan, Puerto Rico 00921, USA
important variables, but other factors are of equal or greaterimportance.
Editorial. Climate-and-health debate warms up. Lancet 1996; 347:
Several efficient malaria vectors are indigenous to North
America, and are common in many areas. The disease was
Patz JA, Epstein PR, Burke TA, et al. Global climate change and
once endemic and widespread in the USA (figure). In 1934,
emerging infectious diseases. JAMA 1996; 276: 217–23.
the year after systematic reporting began, 125 556 cases were
Zucker JR. Changing patterns of autochthonous malaria transmissionin the United States: a review of recent outbreaks. Emerging Infectious
recorded.3 Transmission was also recorded in Canada. When
Diseases 1996; 2: 37–43.
it was founded in 1946, the main function of the Centers for
Ehrenkranz NJ, Ventura AK, Cuadrado RR, et al. Pandemic dengue in
Disease Control and Prevention (CDC) was malaria control,
Caribbean countries and the southern United States—past, present
and it was based in Atlanta because the city was in a
and potential problems. N Engl J Med 1971; 285: 1460–69.
malarious region. The disease was finally eradicated from the
Centers for Disease Control and Prevention. Dengue at the US-Mexico border, 1995. MMWR (in press).
USA in the 1950s. Aedes (Stegomyia) aegypti (L), theprincipal urban vector of yellowfever and dengue, is alsocommon throughout the southern USA. From the 17thcentury onwards, frequent epidemics of yellowfever killedtens of thousands of people as far north as New York. In a
Isotretinoin and azathioprine: a synergy that
single year (1878), there were 100 000 cases and 20 000
deaths. Dengue fever was also common, eight majorpandemics occurring between 1827 and 1946.4 In 1922,
SIR—Acne is common after organ transplantation.1 Steroids
dengue spread east from Texas (500 000 cases) through
are usually blamed but recently cyclosporin has also been
Louisiana, Georgia, and Florida, and then south into the
reported to be associated with severe acne.2 Systemic
Caribbean islands. Savannah, Georgia, reported 30 000
treatment with antibiotics may interact with cyclosporin
cases, 28% of which had haemorrhagic manifestations.
metabolism and absorption. Severe acne responds to
Summer temperatures in the USA were clearly conducive
isotretinoin. Transplant physicians have been reluctant to
to the transmission of these diseases. Indeed, in the southern
prescribe this drug because of concern about enhancing
states they are higher than in many tropical countries. So why
rejection, although several cases have now been reported on
did epidemic transmission cease? The principal factor was
the use of isotretinoin with no deleterious effects on thegrafts.2
A rare side-effect of isotretinoin is curling hair.3 We report
three simultaneous pancreas-kidney (SPK) transplantrecipients, who developed curling hair after isotretinointherapy. The first patient is a 49-year-old man who was puton isotretinoin 100 mg/day 13 months after transplantationbecause of severe acne which did not respond to topicaltherapy. 2 months later he developed extremely curly hair(figure). The second patient was a 46-year-old man whostarted 60 mg isotretinoin 12 months after transplantation,and developed curls in his hair after 60 days. The thirdpatient started isotretinoin 60 mg/day 13 months aftertransplantation and developed curling hairs 3 months later. All patients had an improvement in their acne and nodeleterious effects on pancreas and kidney graft functionwere seen. Cyclosporin dosage had to be increased in two
patients, based on trough levels. Concurrent medication was
Figure: Areas of the USA where malaria was thought to be
prednisone (10 mg/day), cyclosporin (Neoral), and
azathioprine. Furthermore, nifedipine (2/3 patients), sodium
Reproduced from Emerging Infectious Diseases with permission
bicarbonate (3/3), omeprazole (1/3), distigmine bromide
(1/3), atenolol (1/3), hydrochlorothiazide (1/3), and enalapril
Responsabilidade Civil Extracontratual do Estado e Demais Entidades Públicas Condições Especiais Este contrato de seguro garante a responsabilidade civil por danos decorrentes do exercÃcio da função administrativa imputável aos titulares de órgãos, funcionários e agentes públicos do Estado e demais Entidades Públicas, conforme o previsto no art. 8.º do Regime da Responsabilida