Endemias e epidemias na Amazônia: malária e doenças emergentes em áreas ribeirinhas do Rio Madeira: um caso de escola / Endemics and epidemics in the Amazon

Após fazer uma análise da evolução da malária na Amazônia brasileira, detalhando em particular a situação em Rondônia e no município de Porto Velho, onde ocorreram episódios dramáticos de epidemias de malária no passado, os autores apresentam o quadro atual da prevalência de malária nas áreas do Vale do Rio Madeira, que sofrerão impactos com a construção das hidrelétricas de Santo Antônio e Jirau, e alertam sobre a situação particular da malária em áreas ribeirinhas. Nessas áreas, observam-se alta incidência de malária vivax e falciparum, a presença de grande número de portadores assintomáticos de parasitas e altas densidades do vetor Anopheles darlingi o ano todo. Esses elementos, associados à provável chegada de migrantes oriundos de áreas não-endêmicas de Rondônia e de outros Estados do país, atraídos pela possibilidade de trabalho nessas hidrelétricas e oportunidades de comércio, lazer, educação e atividades domésticas, criam condições favoráveis à ocorrência de epidemias de malária e de outras doenças tropicais se não forem realizadas intervenções adequadas de controle, em particular no domínio do saneamento.

Brainstem auditory evoked potentials and somatosensory evoked potentials in cerebral malaria--a prognostic significance.

OBJECTIVE: To study the changes in brainstem auditory evoked potentials (BAEPs) and somatosensory evoked potentials (SSEPs) in cerebral malaria and to see their prognostic significance. METHODS: BAEPs and right median nerve SSEPs were performed in 25 adult patients of strictly defined cerebral malaria in acute stage in a semi-dark, sound proof chamber on four channel computerized multi-basis OTE-Biomedica machine in department of neurology, SP Medical College, Bikaner. RESULTS: The abnormalities of BAEPs were delayed peak latency of wave III in 13/25 (52%) and wave V in 20/25 (80%) patients and delayed interpeak latencies (IPLs) of wave I-III in 9/25 (36%), wave I-V in 15/25 (60%) and wave III-V in 12/25 (48%) patients. In SSEPs delayed N20 was seen in 11/25 (44%); delayed IPLs of N13-N20 (central conduction time; CCT) in 12/25 (48%) patients. Distorted N20 was recorded in 12/25 (48%) patients. Both N13-N20 IPLs in SSEPs and wave III-V IPLs in BAEPs were delayed in five patients and all of them expired. Delayed N13-N20 with normal III-V IPLs was present in seven patients and two of them died, whereas delayed III-V IPLs with normal N13-N20 was present in seven patients, and one of them expired. In remaining six patients both the parameters were normal and one of them died. CONCLUSIONS: The values of BAEPs and SSEPs were abnormal in patients of cerebral malaria and it was observed that BAEPs/SSEPs alone was not useful for predicting the outcome of coma, whereas abnormalities in both was predictive of worst prognosis. The changes in evoked potentials (BAEPs and SSEPs) could be due to either interruption of conduction in central pathways because of structural changes due to petechial hemorrhages and malarial granuloma at multiple levels in the brain including brainstem or due to metabolic abnormalities.